From 698f8c2f01ea549d77d7dc3338a12e04c11057b9 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 14:02:58 +0200 Subject: Adding upstream version 1.64.0+dfsg1. Signed-off-by: Daniel Baumann --- src/librustdoc/Cargo.toml | 41 + src/librustdoc/README.md | 3 + src/librustdoc/askama.toml | 2 + src/librustdoc/clean/auto_trait.rs | 742 +++++ src/librustdoc/clean/blanket_impl.rs | 136 + src/librustdoc/clean/cfg.rs | 588 ++++ src/librustdoc/clean/cfg/tests.rs | 467 ++++ src/librustdoc/clean/inline.rs | 727 +++++ src/librustdoc/clean/mod.rs | 2242 +++++++++++++++ src/librustdoc/clean/render_macro_matchers.rs | 238 ++ src/librustdoc/clean/simplify.rs | 139 + src/librustdoc/clean/types.rs | 2508 +++++++++++++++++ src/librustdoc/clean/types/tests.rs | 70 + src/librustdoc/clean/utils.rs | 616 +++++ src/librustdoc/clean/utils/tests.rs | 41 + src/librustdoc/config.rs | 828 ++++++ src/librustdoc/core.rs | 566 ++++ src/librustdoc/docfs.rs | 78 + src/librustdoc/doctest.rs | 1311 +++++++++ src/librustdoc/doctest/tests.rs | 300 +++ src/librustdoc/error.rs | 59 + src/librustdoc/externalfiles.rs | 107 + src/librustdoc/fold.rs | 103 + src/librustdoc/formats/cache.rs | 569 ++++ src/librustdoc/formats/item_type.rs | 185 ++ src/librustdoc/formats/mod.rs | 101 + src/librustdoc/formats/renderer.rs | 97 + src/librustdoc/html/escape.rs | 40 + src/librustdoc/html/format.rs | 1688 ++++++++++++ src/librustdoc/html/highlight.rs | 805 ++++++ .../html/highlight/fixtures/decorations.html | 2 + .../html/highlight/fixtures/dos_line.html | 3 + .../html/highlight/fixtures/highlight.html | 4 + src/librustdoc/html/highlight/fixtures/sample.html | 37 + src/librustdoc/html/highlight/fixtures/sample.rs | 26 + src/librustdoc/html/highlight/fixtures/union.html | 8 + src/librustdoc/html/highlight/fixtures/union.rs | 8 + src/librustdoc/html/highlight/tests.rs | 81 + src/librustdoc/html/layout.rs | 103 + src/librustdoc/html/length_limit.rs | 119 + src/librustdoc/html/length_limit/tests.rs | 120 + src/librustdoc/html/markdown.rs | 1510 +++++++++++ src/librustdoc/html/markdown/tests.rs | 312 +++ src/librustdoc/html/mod.rs | 15 + src/librustdoc/html/render/context.rs | 762 ++++++ src/librustdoc/html/render/mod.rs | 2849 ++++++++++++++++++++ src/librustdoc/html/render/print_item.rs | 1974 ++++++++++++++ src/librustdoc/html/render/search_index.rs | 589 ++++ src/librustdoc/html/render/span_map.rs | 203 ++ src/librustdoc/html/render/tests.rs | 54 + src/librustdoc/html/render/write_shared.rs | 600 +++++ src/librustdoc/html/sources.rs | 303 +++ src/librustdoc/html/static/.eslintrc.js | 96 + src/librustdoc/html/static/COPYRIGHT.txt | 46 + src/librustdoc/html/static/LICENSE-APACHE.txt | 201 ++ src/librustdoc/html/static/LICENSE-MIT.txt | 23 + src/librustdoc/html/static/css/normalize.css | 2 + src/librustdoc/html/static/css/noscript.css | 20 + src/librustdoc/html/static/css/rustdoc.css | 2335 ++++++++++++++++ src/librustdoc/html/static/css/settings.css | 90 + src/librustdoc/html/static/css/themes/ayu.css | 563 ++++ src/librustdoc/html/static/css/themes/dark.css | 409 +++ src/librustdoc/html/static/css/themes/light.css | 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src/librustdoc/html/templates/page.html | 148 + src/librustdoc/html/templates/print_item.html | 30 + src/librustdoc/html/tests.rs | 50 + src/librustdoc/html/toc.rs | 191 ++ src/librustdoc/html/toc/tests.rs | 79 + src/librustdoc/html/url_parts_builder.rs | 180 ++ src/librustdoc/html/url_parts_builder/tests.rs | 64 + src/librustdoc/json/conversions.rs | 798 ++++++ src/librustdoc/json/mod.rs | 327 +++ src/librustdoc/lib.rs | 868 ++++++ src/librustdoc/lint.rs | 202 ++ src/librustdoc/markdown.rs | 151 ++ src/librustdoc/passes/bare_urls.rs | 112 + src/librustdoc/passes/calculate_doc_coverage.rs | 276 ++ src/librustdoc/passes/check_code_block_syntax.rs | 205 ++ src/librustdoc/passes/check_doc_test_visibility.rs | 145 + src/librustdoc/passes/collect_intra_doc_links.rs | 2161 +++++++++++++++ .../passes/collect_intra_doc_links/early.rs | 405 +++ src/librustdoc/passes/collect_trait_impls.rs | 273 ++ src/librustdoc/passes/html_tags.rs | 303 +++ src/librustdoc/passes/mod.rs | 212 ++ 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mode 100644 src/librustdoc/visit.rs create mode 100644 src/librustdoc/visit_ast.rs create mode 100644 src/librustdoc/visit_lib.rs (limited to 'src/librustdoc') diff --git a/src/librustdoc/Cargo.toml b/src/librustdoc/Cargo.toml new file mode 100644 index 000000000..ddaa7438e --- /dev/null +++ b/src/librustdoc/Cargo.toml @@ -0,0 +1,41 @@ +[package] +name = "rustdoc" +version = "0.0.0" +edition = "2021" + +[lib] +path = "lib.rs" + +[dependencies] +arrayvec = { version = "0.7", default-features = false } +askama = { version = "0.11", default-features = false, features = ["config"] } +atty = "0.2" +pulldown-cmark = { version = "0.9.2", default-features = false } +minifier = "0.2.1" +serde = { version = "1.0", features = ["derive"] } +serde_json = "1.0" +smallvec = "1.8.1" +tempfile = "3" +itertools = "0.10.1" +regex = "1" +rustdoc-json-types = { path = "../rustdoc-json-types" } +tracing = "0.1" +tracing-tree = "0.2.0" +once_cell = "1.10.0" + +[dependencies.tracing-subscriber] +version = "0.3.3" +default-features = false +features = ["fmt", "env-filter", "smallvec", "parking_lot", "ansi"] + +[target.'cfg(windows)'.dependencies] +rayon = "1.5.1" + +[dev-dependencies] +expect-test = "1.0" + +[features] +jemalloc = [] + +[package.metadata.rust-analyzer] +rustc_private = true diff --git a/src/librustdoc/README.md b/src/librustdoc/README.md new file mode 100644 index 000000000..5a5f54706 --- /dev/null +++ b/src/librustdoc/README.md @@ -0,0 +1,3 @@ +For more information about how `librustdoc` works, see the [rustc dev guide]. + +[rustc dev guide]: https://rustc-dev-guide.rust-lang.org/rustdoc.html diff --git a/src/librustdoc/askama.toml b/src/librustdoc/askama.toml new file mode 100644 index 000000000..0c984f637 --- /dev/null +++ b/src/librustdoc/askama.toml @@ -0,0 +1,2 @@ +[general] +dirs = ["html/templates"] diff --git a/src/librustdoc/clean/auto_trait.rs b/src/librustdoc/clean/auto_trait.rs new file mode 100644 index 000000000..af33c1a6a --- /dev/null +++ b/src/librustdoc/clean/auto_trait.rs @@ -0,0 +1,742 @@ +use rustc_data_structures::fx::FxHashSet; +use rustc_hir as hir; +use rustc_hir::lang_items::LangItem; +use rustc_middle::ty::{self, Region, RegionVid, TypeFoldable, TypeSuperFoldable}; +use rustc_trait_selection::traits::auto_trait::{self, AutoTraitResult}; + +use std::fmt::Debug; + +use super::*; + +#[derive(Eq, PartialEq, Hash, Copy, Clone, Debug)] +enum RegionTarget<'tcx> { + Region(Region<'tcx>), + RegionVid(RegionVid), +} + +#[derive(Default, Debug, Clone)] +struct RegionDeps<'tcx> { + larger: FxHashSet>, + smaller: FxHashSet>, +} + +pub(crate) struct AutoTraitFinder<'a, 'tcx> { + pub(crate) cx: &'a mut core::DocContext<'tcx>, +} + +impl<'a, 'tcx> AutoTraitFinder<'a, 'tcx> +where + 'tcx: 'a, // should be an implied bound; rustc bug #98852. +{ + pub(crate) fn new(cx: &'a mut core::DocContext<'tcx>) -> Self { + AutoTraitFinder { cx } + } + + fn generate_for_trait( + &mut self, + ty: Ty<'tcx>, + trait_def_id: DefId, + param_env: ty::ParamEnv<'tcx>, + item_def_id: DefId, + f: &auto_trait::AutoTraitFinder<'tcx>, + // If this is set, show only negative trait implementations, not positive ones. + discard_positive_impl: bool, + ) -> Option { + let tcx = self.cx.tcx; + let trait_ref = ty::TraitRef { def_id: trait_def_id, substs: tcx.mk_substs_trait(ty, &[]) }; + if !self.cx.generated_synthetics.insert((ty, trait_def_id)) { + debug!("get_auto_trait_impl_for({:?}): already generated, aborting", trait_ref); + return None; + } + + let result = f.find_auto_trait_generics(ty, param_env, trait_def_id, |info| { + let region_data = info.region_data; + + let names_map = tcx + .generics_of(item_def_id) + .params + .iter() + .filter_map(|param| match param.kind { + ty::GenericParamDefKind::Lifetime => Some(param.name), + _ => None, + }) + .map(|name| (name, Lifetime(name))) + .collect(); + let lifetime_predicates = Self::handle_lifetimes(®ion_data, &names_map); + let new_generics = self.param_env_to_generics( + item_def_id, + info.full_user_env, + lifetime_predicates, + info.vid_to_region, + ); + + debug!( + "find_auto_trait_generics(item_def_id={:?}, trait_def_id={:?}): \ + finished with {:?}", + item_def_id, trait_def_id, new_generics + ); + + new_generics + }); + + let polarity; + let new_generics = match result { + AutoTraitResult::PositiveImpl(new_generics) => { + polarity = ty::ImplPolarity::Positive; + if discard_positive_impl { + return None; + } + new_generics + } + AutoTraitResult::NegativeImpl => { + polarity = ty::ImplPolarity::Negative; + + // For negative impls, we use the generic params, but *not* the predicates, + // from the original type. Otherwise, the displayed impl appears to be a + // conditional negative impl, when it's really unconditional. + // + // For example, consider the struct Foo(*mut T). Using + // the original predicates in our impl would cause us to generate + // `impl !Send for Foo`, which makes it appear that Foo + // implements Send where T is not copy. + // + // Instead, we generate `impl !Send for Foo`, which better + // expresses the fact that `Foo` never implements `Send`, + // regardless of the choice of `T`. + let raw_generics = clean_ty_generics( + self.cx, + tcx.generics_of(item_def_id), + ty::GenericPredicates::default(), + ); + let params = raw_generics.params; + + Generics { params, where_predicates: Vec::new() } + } + AutoTraitResult::ExplicitImpl => return None, + }; + + Some(Item { + name: None, + attrs: Default::default(), + visibility: Inherited, + item_id: ItemId::Auto { trait_: trait_def_id, for_: item_def_id }, + kind: Box::new(ImplItem(Box::new(Impl { + unsafety: hir::Unsafety::Normal, + generics: new_generics, + trait_: Some(clean_trait_ref_with_bindings(self.cx, trait_ref, &[])), + for_: clean_middle_ty(ty, self.cx, None), + items: Vec::new(), + polarity, + kind: ImplKind::Auto, + }))), + cfg: None, + }) + } + + pub(crate) fn get_auto_trait_impls(&mut self, item_def_id: DefId) -> Vec { + let tcx = self.cx.tcx; + let param_env = tcx.param_env(item_def_id); + let ty = tcx.type_of(item_def_id); + let f = auto_trait::AutoTraitFinder::new(tcx); + + debug!("get_auto_trait_impls({:?})", ty); + let auto_traits: Vec<_> = self.cx.auto_traits.iter().copied().collect(); + let mut auto_traits: Vec = auto_traits + .into_iter() + .filter_map(|trait_def_id| { + self.generate_for_trait(ty, trait_def_id, param_env, item_def_id, &f, false) + }) + .collect(); + // We are only interested in case the type *doesn't* implement the Sized trait. + if !ty.is_sized(tcx.at(rustc_span::DUMMY_SP), param_env) { + // In case `#![no_core]` is used, `sized_trait` returns nothing. + if let Some(item) = tcx.lang_items().sized_trait().and_then(|sized_trait_did| { + self.generate_for_trait(ty, sized_trait_did, param_env, item_def_id, &f, true) + }) { + auto_traits.push(item); + } + } + auto_traits + } + + fn get_lifetime(region: Region<'_>, names_map: &FxHashMap) -> Lifetime { + region_name(region) + .map(|name| { + names_map.get(&name).unwrap_or_else(|| { + panic!("Missing lifetime with name {:?} for {:?}", name.as_str(), region) + }) + }) + .unwrap_or(&Lifetime::statik()) + .clone() + } + + /// This method calculates two things: Lifetime constraints of the form `'a: 'b`, + /// and region constraints of the form `RegionVid: 'a` + /// + /// This is essentially a simplified version of lexical_region_resolve. However, + /// handle_lifetimes determines what *needs be* true in order for an impl to hold. + /// lexical_region_resolve, along with much of the rest of the compiler, is concerned + /// with determining if a given set up constraints/predicates *are* met, given some + /// starting conditions (e.g., user-provided code). For this reason, it's easier + /// to perform the calculations we need on our own, rather than trying to make + /// existing inference/solver code do what we want. + fn handle_lifetimes<'cx>( + regions: &RegionConstraintData<'cx>, + names_map: &FxHashMap, + ) -> Vec { + // Our goal is to 'flatten' the list of constraints by eliminating + // all intermediate RegionVids. At the end, all constraints should + // be between Regions (aka region variables). This gives us the information + // we need to create the Generics. + let mut finished: FxHashMap<_, Vec<_>> = Default::default(); + + let mut vid_map: FxHashMap, RegionDeps<'_>> = Default::default(); + + // Flattening is done in two parts. First, we insert all of the constraints + // into a map. Each RegionTarget (either a RegionVid or a Region) maps + // to its smaller and larger regions. Note that 'larger' regions correspond + // to sub-regions in Rust code (e.g., in 'a: 'b, 'a is the larger region). + for constraint in regions.constraints.keys() { + match *constraint { + Constraint::VarSubVar(r1, r2) => { + { + let deps1 = vid_map.entry(RegionTarget::RegionVid(r1)).or_default(); + deps1.larger.insert(RegionTarget::RegionVid(r2)); + } + + let deps2 = vid_map.entry(RegionTarget::RegionVid(r2)).or_default(); + deps2.smaller.insert(RegionTarget::RegionVid(r1)); + } + Constraint::RegSubVar(region, vid) => { + let deps = vid_map.entry(RegionTarget::RegionVid(vid)).or_default(); + deps.smaller.insert(RegionTarget::Region(region)); + } + Constraint::VarSubReg(vid, region) => { + let deps = vid_map.entry(RegionTarget::RegionVid(vid)).or_default(); + deps.larger.insert(RegionTarget::Region(region)); + } + Constraint::RegSubReg(r1, r2) => { + // The constraint is already in the form that we want, so we're done with it + // Desired order is 'larger, smaller', so flip then + if region_name(r1) != region_name(r2) { + finished + .entry(region_name(r2).expect("no region_name found")) + .or_default() + .push(r1); + } + } + } + } + + // Here, we 'flatten' the map one element at a time. + // All of the element's sub and super regions are connected + // to each other. For example, if we have a graph that looks like this: + // + // (A, B) - C - (D, E) + // Where (A, B) are subregions, and (D,E) are super-regions + // + // then after deleting 'C', the graph will look like this: + // ... - A - (D, E ...) + // ... - B - (D, E, ...) + // (A, B, ...) - D - ... + // (A, B, ...) - E - ... + // + // where '...' signifies the existing sub and super regions of an entry + // When two adjacent ty::Regions are encountered, we've computed a final + // constraint, and add it to our list. Since we make sure to never re-add + // deleted items, this process will always finish. + while !vid_map.is_empty() { + let target = *vid_map.keys().next().expect("Keys somehow empty"); + let deps = vid_map.remove(&target).expect("Entry somehow missing"); + + for smaller in deps.smaller.iter() { + for larger in deps.larger.iter() { + match (smaller, larger) { + (&RegionTarget::Region(r1), &RegionTarget::Region(r2)) => { + if region_name(r1) != region_name(r2) { + finished + .entry(region_name(r2).expect("no region name found")) + .or_default() + .push(r1) // Larger, smaller + } + } + (&RegionTarget::RegionVid(_), &RegionTarget::Region(_)) => { + if let Entry::Occupied(v) = vid_map.entry(*smaller) { + let smaller_deps = v.into_mut(); + smaller_deps.larger.insert(*larger); + smaller_deps.larger.remove(&target); + } + } + (&RegionTarget::Region(_), &RegionTarget::RegionVid(_)) => { + if let Entry::Occupied(v) = vid_map.entry(*larger) { + let deps = v.into_mut(); + deps.smaller.insert(*smaller); + deps.smaller.remove(&target); + } + } + (&RegionTarget::RegionVid(_), &RegionTarget::RegionVid(_)) => { + if let Entry::Occupied(v) = vid_map.entry(*smaller) { + let smaller_deps = v.into_mut(); + smaller_deps.larger.insert(*larger); + smaller_deps.larger.remove(&target); + } + + if let Entry::Occupied(v) = vid_map.entry(*larger) { + let larger_deps = v.into_mut(); + larger_deps.smaller.insert(*smaller); + larger_deps.smaller.remove(&target); + } + } + } + } + } + } + + let lifetime_predicates = names_map + .iter() + .flat_map(|(name, lifetime)| { + let empty = Vec::new(); + let bounds: FxHashSet = finished + .get(name) + .unwrap_or(&empty) + .iter() + .map(|region| GenericBound::Outlives(Self::get_lifetime(*region, names_map))) + .collect(); + + if bounds.is_empty() { + return None; + } + Some(WherePredicate::RegionPredicate { + lifetime: lifetime.clone(), + bounds: bounds.into_iter().collect(), + }) + }) + .collect(); + + lifetime_predicates + } + + fn extract_for_generics(&self, pred: ty::Predicate<'tcx>) -> FxHashSet { + let bound_predicate = pred.kind(); + let tcx = self.cx.tcx; + let regions = match bound_predicate.skip_binder() { + ty::PredicateKind::Trait(poly_trait_pred) => { + tcx.collect_referenced_late_bound_regions(&bound_predicate.rebind(poly_trait_pred)) + } + ty::PredicateKind::Projection(poly_proj_pred) => { + tcx.collect_referenced_late_bound_regions(&bound_predicate.rebind(poly_proj_pred)) + } + _ => return FxHashSet::default(), + }; + + regions + .into_iter() + .filter_map(|br| { + match br { + // We only care about named late bound regions, as we need to add them + // to the 'for<>' section + ty::BrNamed(_, name) => Some(GenericParamDef { + name, + kind: GenericParamDefKind::Lifetime { outlives: vec![] }, + }), + _ => None, + } + }) + .collect() + } + + fn make_final_bounds( + &self, + ty_to_bounds: FxHashMap>, + ty_to_fn: FxHashMap)>, + lifetime_to_bounds: FxHashMap>, + ) -> Vec { + ty_to_bounds + .into_iter() + .flat_map(|(ty, mut bounds)| { + if let Some((ref poly_trait, ref output)) = ty_to_fn.get(&ty) { + let mut new_path = poly_trait.trait_.clone(); + let last_segment = new_path.segments.pop().expect("segments were empty"); + + let (old_input, old_output) = match last_segment.args { + GenericArgs::AngleBracketed { args, .. } => { + let types = args + .iter() + .filter_map(|arg| match arg { + GenericArg::Type(ty) => Some(ty.clone()), + _ => None, + }) + .collect(); + (types, None) + } + GenericArgs::Parenthesized { inputs, output } => (inputs, output), + }; + + let output = output.as_ref().cloned().map(Box::new); + if old_output.is_some() && old_output != output { + panic!("Output mismatch for {:?} {:?} {:?}", ty, old_output, output); + } + + let new_params = GenericArgs::Parenthesized { inputs: old_input, output }; + + new_path + .segments + .push(PathSegment { name: last_segment.name, args: new_params }); + + bounds.insert(GenericBound::TraitBound( + PolyTrait { + trait_: new_path, + generic_params: poly_trait.generic_params.clone(), + }, + hir::TraitBoundModifier::None, + )); + } + if bounds.is_empty() { + return None; + } + + let mut bounds_vec = bounds.into_iter().collect(); + self.sort_where_bounds(&mut bounds_vec); + + Some(WherePredicate::BoundPredicate { + ty, + bounds: bounds_vec, + bound_params: Vec::new(), + }) + }) + .chain( + lifetime_to_bounds.into_iter().filter(|&(_, ref bounds)| !bounds.is_empty()).map( + |(lifetime, bounds)| { + let mut bounds_vec = bounds.into_iter().collect(); + self.sort_where_bounds(&mut bounds_vec); + WherePredicate::RegionPredicate { lifetime, bounds: bounds_vec } + }, + ), + ) + .collect() + } + + /// Converts the calculated `ParamEnv` and lifetime information to a [`clean::Generics`](Generics), suitable for + /// display on the docs page. Cleaning the `Predicates` produces sub-optimal [`WherePredicate`]s, + /// so we fix them up: + /// + /// * Multiple bounds for the same type are coalesced into one: e.g., `T: Copy`, `T: Debug` + /// becomes `T: Copy + Debug` + /// * `Fn` bounds are handled specially - instead of leaving it as `T: Fn(), = + /// K`, we use the dedicated syntax `T: Fn() -> K` + /// * We explicitly add a `?Sized` bound if we didn't find any `Sized` predicates for a type + fn param_env_to_generics( + &mut self, + item_def_id: DefId, + param_env: ty::ParamEnv<'tcx>, + mut existing_predicates: Vec, + vid_to_region: FxHashMap>, + ) -> Generics { + debug!( + "param_env_to_generics(item_def_id={:?}, param_env={:?}, \ + existing_predicates={:?})", + item_def_id, param_env, existing_predicates + ); + + let tcx = self.cx.tcx; + + // The `Sized` trait must be handled specially, since we only display it when + // it is *not* required (i.e., '?Sized') + let sized_trait = tcx.require_lang_item(LangItem::Sized, None); + + let mut replacer = RegionReplacer { vid_to_region: &vid_to_region, tcx }; + + let orig_bounds: FxHashSet<_> = tcx.param_env(item_def_id).caller_bounds().iter().collect(); + let clean_where_predicates = param_env + .caller_bounds() + .iter() + .filter(|p| { + !orig_bounds.contains(p) + || match p.kind().skip_binder() { + ty::PredicateKind::Trait(pred) => pred.def_id() == sized_trait, + _ => false, + } + }) + .map(|p| p.fold_with(&mut replacer)); + + let raw_generics = clean_ty_generics( + self.cx, + tcx.generics_of(item_def_id), + tcx.explicit_predicates_of(item_def_id), + ); + let mut generic_params = raw_generics.params; + + debug!("param_env_to_generics({:?}): generic_params={:?}", item_def_id, generic_params); + + let mut has_sized = FxHashSet::default(); + let mut ty_to_bounds: FxHashMap<_, FxHashSet<_>> = Default::default(); + let mut lifetime_to_bounds: FxHashMap<_, FxHashSet<_>> = Default::default(); + let mut ty_to_traits: FxHashMap> = Default::default(); + + let mut ty_to_fn: FxHashMap)> = Default::default(); + + for p in clean_where_predicates { + let (orig_p, p) = (p, p.clean(self.cx)); + if p.is_none() { + continue; + } + let p = p.unwrap(); + match p { + WherePredicate::BoundPredicate { ty, mut bounds, .. } => { + // Writing a projection trait bound of the form + // ::Name : ?Sized + // is illegal, because ?Sized bounds can only + // be written in the (here, nonexistent) definition + // of the type. + // Therefore, we make sure that we never add a ?Sized + // bound for projections + if let Type::QPath { .. } = ty { + has_sized.insert(ty.clone()); + } + + if bounds.is_empty() { + continue; + } + + let mut for_generics = self.extract_for_generics(orig_p); + + assert!(bounds.len() == 1); + let mut b = bounds.pop().expect("bounds were empty"); + + if b.is_sized_bound(self.cx) { + has_sized.insert(ty.clone()); + } else if !b + .get_trait_path() + .and_then(|trait_| { + ty_to_traits + .get(&ty) + .map(|bounds| bounds.contains(&strip_path_generics(trait_))) + }) + .unwrap_or(false) + { + // If we've already added a projection bound for the same type, don't add + // this, as it would be a duplicate + + // Handle any 'Fn/FnOnce/FnMut' bounds specially, + // as we want to combine them with any 'Output' qpaths + // later + + let is_fn = match b { + GenericBound::TraitBound(ref mut p, _) => { + // Insert regions into the for_generics hash map first, to ensure + // that we don't end up with duplicate bounds (e.g., for<'b, 'b>) + for_generics.extend(p.generic_params.clone()); + p.generic_params = for_generics.into_iter().collect(); + self.is_fn_trait(&p.trait_) + } + _ => false, + }; + + let poly_trait = b.get_poly_trait().expect("Cannot get poly trait"); + + if is_fn { + ty_to_fn + .entry(ty.clone()) + .and_modify(|e| *e = (poly_trait.clone(), e.1.clone())) + .or_insert(((poly_trait.clone()), None)); + + ty_to_bounds.entry(ty.clone()).or_default(); + } else { + ty_to_bounds.entry(ty.clone()).or_default().insert(b.clone()); + } + } + } + WherePredicate::RegionPredicate { lifetime, bounds } => { + lifetime_to_bounds.entry(lifetime).or_default().extend(bounds); + } + WherePredicate::EqPredicate { lhs, rhs } => { + match lhs { + Type::QPath { ref assoc, ref self_type, ref trait_, .. } => { + let ty = &*self_type; + let mut new_trait = trait_.clone(); + + if self.is_fn_trait(trait_) && assoc.name == sym::Output { + ty_to_fn + .entry(*ty.clone()) + .and_modify(|e| { + *e = (e.0.clone(), Some(rhs.ty().unwrap().clone())) + }) + .or_insert(( + PolyTrait { + trait_: trait_.clone(), + generic_params: Vec::new(), + }, + Some(rhs.ty().unwrap().clone()), + )); + continue; + } + + let args = &mut new_trait + .segments + .last_mut() + .expect("segments were empty") + .args; + + match args { + // Convert something like ' = u8' + // to 'T: Iterator' + GenericArgs::AngleBracketed { ref mut bindings, .. } => { + bindings.push(TypeBinding { + assoc: *assoc.clone(), + kind: TypeBindingKind::Equality { term: rhs }, + }); + } + GenericArgs::Parenthesized { .. } => { + existing_predicates.push(WherePredicate::EqPredicate { + lhs: lhs.clone(), + rhs, + }); + continue; // If something other than a Fn ends up + // with parentheses, leave it alone + } + } + + let bounds = ty_to_bounds.entry(*ty.clone()).or_default(); + + bounds.insert(GenericBound::TraitBound( + PolyTrait { trait_: new_trait, generic_params: Vec::new() }, + hir::TraitBoundModifier::None, + )); + + // Remove any existing 'plain' bound (e.g., 'T: Iterator`) so + // that we don't see a + // duplicate bound like `T: Iterator + Iterator` + // on the docs page. + bounds.remove(&GenericBound::TraitBound( + PolyTrait { trait_: trait_.clone(), generic_params: Vec::new() }, + hir::TraitBoundModifier::None, + )); + // Avoid creating any new duplicate bounds later in the outer + // loop + ty_to_traits.entry(*ty.clone()).or_default().insert(trait_.clone()); + } + _ => panic!("Unexpected LHS {:?} for {:?}", lhs, item_def_id), + } + } + }; + } + + let final_bounds = self.make_final_bounds(ty_to_bounds, ty_to_fn, lifetime_to_bounds); + + existing_predicates.extend(final_bounds); + + for param in generic_params.iter_mut() { + match param.kind { + GenericParamDefKind::Type { ref mut default, ref mut bounds, .. } => { + // We never want something like `impl`. + default.take(); + let generic_ty = Type::Generic(param.name); + if !has_sized.contains(&generic_ty) { + bounds.insert(0, GenericBound::maybe_sized(self.cx)); + } + } + GenericParamDefKind::Lifetime { .. } => {} + GenericParamDefKind::Const { ref mut default, .. } => { + // We never want something like `impl` + default.take(); + } + } + } + + self.sort_where_predicates(&mut existing_predicates); + + Generics { params: generic_params, where_predicates: existing_predicates } + } + + /// Ensure that the predicates are in a consistent order. The precise + /// ordering doesn't actually matter, but it's important that + /// a given set of predicates always appears in the same order - + /// both for visual consistency between 'rustdoc' runs, and to + /// make writing tests much easier + #[inline] + fn sort_where_predicates(&self, predicates: &mut Vec) { + // We should never have identical bounds - and if we do, + // they're visually identical as well. Therefore, using + // an unstable sort is fine. + self.unstable_debug_sort(predicates); + } + + /// Ensure that the bounds are in a consistent order. The precise + /// ordering doesn't actually matter, but it's important that + /// a given set of bounds always appears in the same order - + /// both for visual consistency between 'rustdoc' runs, and to + /// make writing tests much easier + #[inline] + fn sort_where_bounds(&self, bounds: &mut Vec) { + // We should never have identical bounds - and if we do, + // they're visually identical as well. Therefore, using + // an unstable sort is fine. + self.unstable_debug_sort(bounds); + } + + /// This might look horrendously hacky, but it's actually not that bad. + /// + /// For performance reasons, we use several different FxHashMaps + /// in the process of computing the final set of where predicates. + /// However, the iteration order of a HashMap is completely unspecified. + /// In fact, the iteration of an FxHashMap can even vary between platforms, + /// since FxHasher has different behavior for 32-bit and 64-bit platforms. + /// + /// Obviously, it's extremely undesirable for documentation rendering + /// to be dependent on the platform it's run on. Apart from being confusing + /// to end users, it makes writing tests much more difficult, as predicates + /// can appear in any order in the final result. + /// + /// To solve this problem, we sort WherePredicates and GenericBounds + /// by their Debug string. The thing to keep in mind is that we don't really + /// care what the final order is - we're synthesizing an impl or bound + /// ourselves, so any order can be considered equally valid. By sorting the + /// predicates and bounds, however, we ensure that for a given codebase, all + /// auto-trait impls always render in exactly the same way. + /// + /// Using the Debug implementation for sorting prevents us from needing to + /// write quite a bit of almost entirely useless code (e.g., how should two + /// Types be sorted relative to each other). It also allows us to solve the + /// problem for both WherePredicates and GenericBounds at the same time. This + /// approach is probably somewhat slower, but the small number of items + /// involved (impls rarely have more than a few bounds) means that it + /// shouldn't matter in practice. + fn unstable_debug_sort(&self, vec: &mut Vec) { + vec.sort_by_cached_key(|x| format!("{:?}", x)) + } + + fn is_fn_trait(&self, path: &Path) -> bool { + let tcx = self.cx.tcx; + let did = path.def_id(); + did == tcx.require_lang_item(LangItem::Fn, None) + || did == tcx.require_lang_item(LangItem::FnMut, None) + || did == tcx.require_lang_item(LangItem::FnOnce, None) + } +} + +fn region_name(region: Region<'_>) -> Option { + match *region { + ty::ReEarlyBound(r) => Some(r.name), + _ => None, + } +} + +/// Replaces all [`ty::RegionVid`]s in a type with [`ty::Region`]s, using the provided map. +struct RegionReplacer<'a, 'tcx> { + vid_to_region: &'a FxHashMap>, + tcx: TyCtxt<'tcx>, +} + +impl<'a, 'tcx> TypeFolder<'tcx> for RegionReplacer<'a, 'tcx> { + fn tcx<'b>(&'b self) -> TyCtxt<'tcx> { + self.tcx + } + + fn fold_region(&mut self, r: ty::Region<'tcx>) -> ty::Region<'tcx> { + (match *r { + ty::ReVar(vid) => self.vid_to_region.get(&vid).cloned(), + _ => None, + }) + .unwrap_or_else(|| r.super_fold_with(self)) + } +} diff --git a/src/librustdoc/clean/blanket_impl.rs b/src/librustdoc/clean/blanket_impl.rs new file mode 100644 index 000000000..01dd95e6e --- /dev/null +++ b/src/librustdoc/clean/blanket_impl.rs @@ -0,0 +1,136 @@ +use crate::rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt; +use rustc_hir as hir; +use rustc_infer::infer::{InferOk, TyCtxtInferExt}; +use rustc_infer::traits; +use rustc_middle::ty::subst::Subst; +use rustc_middle::ty::ToPredicate; +use rustc_span::DUMMY_SP; + +use super::*; + +pub(crate) struct BlanketImplFinder<'a, 'tcx> { + pub(crate) cx: &'a mut core::DocContext<'tcx>, +} + +impl<'a, 'tcx> BlanketImplFinder<'a, 'tcx> { + pub(crate) fn get_blanket_impls(&mut self, item_def_id: DefId) -> Vec { + let param_env = self.cx.tcx.param_env(item_def_id); + let ty = self.cx.tcx.bound_type_of(item_def_id); + + trace!("get_blanket_impls({:?})", ty); + let mut impls = Vec::new(); + self.cx.with_all_traits(|cx, all_traits| { + for &trait_def_id in all_traits { + if !cx.cache.access_levels.is_public(trait_def_id) + || cx.generated_synthetics.get(&(ty.0, trait_def_id)).is_some() + { + continue; + } + // NOTE: doesn't use `for_each_relevant_impl` to avoid looking at anything besides blanket impls + let trait_impls = cx.tcx.trait_impls_of(trait_def_id); + for &impl_def_id in trait_impls.blanket_impls() { + trace!( + "get_blanket_impls: Considering impl for trait '{:?}' {:?}", + trait_def_id, + impl_def_id + ); + let trait_ref = cx.tcx.bound_impl_trait_ref(impl_def_id).unwrap(); + let is_param = matches!(trait_ref.0.self_ty().kind(), ty::Param(_)); + let may_apply = is_param && cx.tcx.infer_ctxt().enter(|infcx| { + let substs = infcx.fresh_substs_for_item(DUMMY_SP, item_def_id); + let ty = ty.subst(infcx.tcx, substs); + let param_env = EarlyBinder(param_env).subst(infcx.tcx, substs); + + let impl_substs = infcx.fresh_substs_for_item(DUMMY_SP, impl_def_id); + let trait_ref = trait_ref.subst(infcx.tcx, impl_substs); + + // Require the type the impl is implemented on to match + // our type, and ignore the impl if there was a mismatch. + let cause = traits::ObligationCause::dummy(); + let eq_result = infcx.at(&cause, param_env).eq(trait_ref.self_ty(), ty); + if let Ok(InferOk { value: (), obligations }) = eq_result { + // FIXME(eddyb) ignoring `obligations` might cause false positives. + drop(obligations); + + trace!( + "invoking predicate_may_hold: param_env={:?}, trait_ref={:?}, ty={:?}", + param_env, + trait_ref, + ty + ); + let predicates = cx + .tcx + .predicates_of(impl_def_id) + .instantiate(cx.tcx, impl_substs) + .predicates + .into_iter() + .chain(Some( + ty::Binder::dummy(trait_ref) + .to_poly_trait_predicate() + .map_bound(ty::PredicateKind::Trait) + .to_predicate(infcx.tcx), + )); + for predicate in predicates { + debug!("testing predicate {:?}", predicate); + let obligation = traits::Obligation::new( + traits::ObligationCause::dummy(), + param_env, + predicate, + ); + match infcx.evaluate_obligation(&obligation) { + Ok(eval_result) if eval_result.may_apply() => {} + Err(traits::OverflowError::Canonical) => {} + Err(traits::OverflowError::ErrorReporting) => {} + _ => { + return false; + } + } + } + true + } else { + false + } + }); + debug!( + "get_blanket_impls: found applicable impl: {} for trait_ref={:?}, ty={:?}", + may_apply, trait_ref, ty + ); + if !may_apply { + continue; + } + + cx.generated_synthetics.insert((ty.0, trait_def_id)); + + impls.push(Item { + name: None, + attrs: Default::default(), + visibility: Inherited, + item_id: ItemId::Blanket { impl_id: impl_def_id, for_: item_def_id }, + kind: Box::new(ImplItem(Box::new(Impl { + unsafety: hir::Unsafety::Normal, + generics: clean_ty_generics( + cx, + cx.tcx.generics_of(impl_def_id), + cx.tcx.explicit_predicates_of(impl_def_id), + ), + // FIXME(eddyb) compute both `trait_` and `for_` from + // the post-inference `trait_ref`, as it's more accurate. + trait_: Some(clean_trait_ref_with_bindings(cx, trait_ref.0, &[])), + for_: clean_middle_ty(ty.0, cx, None), + items: cx.tcx + .associated_items(impl_def_id) + .in_definition_order() + .map(|x| x.clean(cx)) + .collect::>(), + polarity: ty::ImplPolarity::Positive, + kind: ImplKind::Blanket(Box::new(clean_middle_ty(trait_ref.0.self_ty(), cx, None))), + }))), + cfg: None, + }); + } + } + }); + + impls + } +} diff --git a/src/librustdoc/clean/cfg.rs b/src/librustdoc/clean/cfg.rs new file mode 100644 index 000000000..f33f5d27d --- /dev/null +++ b/src/librustdoc/clean/cfg.rs @@ -0,0 +1,588 @@ +//! The representation of a `#[doc(cfg(...))]` attribute. + +// FIXME: Once the portability lint RFC is implemented (see tracking issue #41619), +// switch to use those structures instead. + +use std::fmt::{self, Write}; +use std::mem; +use std::ops; + +use rustc_ast::{LitKind, MetaItem, MetaItemKind, NestedMetaItem}; +use rustc_data_structures::fx::FxHashSet; +use rustc_feature::Features; +use rustc_session::parse::ParseSess; +use rustc_span::symbol::{sym, Symbol}; + +use rustc_span::Span; + +use crate::html::escape::Escape; + +#[cfg(test)] +mod tests; + +#[derive(Clone, Debug, PartialEq, Eq, Hash)] +pub(crate) enum Cfg { + /// Accepts all configurations. + True, + /// Denies all configurations. + False, + /// A generic configuration option, e.g., `test` or `target_os = "linux"`. + Cfg(Symbol, Option), + /// Negates a configuration requirement, i.e., `not(x)`. + Not(Box), + /// Union of a list of configuration requirements, i.e., `any(...)`. + Any(Vec), + /// Intersection of a list of configuration requirements, i.e., `all(...)`. + All(Vec), +} + +#[derive(PartialEq, Debug)] +pub(crate) struct InvalidCfgError { + pub(crate) msg: &'static str, + pub(crate) span: Span, +} + +impl Cfg { + /// Parses a `NestedMetaItem` into a `Cfg`. + fn parse_nested( + nested_cfg: &NestedMetaItem, + exclude: &FxHashSet, + ) -> Result, InvalidCfgError> { + match nested_cfg { + NestedMetaItem::MetaItem(ref cfg) => Cfg::parse_without(cfg, exclude), + NestedMetaItem::Literal(ref lit) => { + Err(InvalidCfgError { msg: "unexpected literal", span: lit.span }) + } + } + } + + pub(crate) fn parse_without( + cfg: &MetaItem, + exclude: &FxHashSet, + ) -> Result, InvalidCfgError> { + let name = match cfg.ident() { + Some(ident) => ident.name, + None => { + return Err(InvalidCfgError { + msg: "expected a single identifier", + span: cfg.span, + }); + } + }; + match cfg.kind { + MetaItemKind::Word => { + let cfg = Cfg::Cfg(name, None); + if exclude.contains(&cfg) { Ok(None) } else { Ok(Some(cfg)) } + } + MetaItemKind::NameValue(ref lit) => match lit.kind { + LitKind::Str(value, _) => { + let cfg = Cfg::Cfg(name, Some(value)); + if exclude.contains(&cfg) { Ok(None) } else { Ok(Some(cfg)) } + } + _ => Err(InvalidCfgError { + // FIXME: if the main #[cfg] syntax decided to support non-string literals, + // this should be changed as well. + msg: "value of cfg option should be a string literal", + span: lit.span, + }), + }, + MetaItemKind::List(ref items) => { + let orig_len = items.len(); + let sub_cfgs = + items.iter().filter_map(|i| Cfg::parse_nested(i, exclude).transpose()); + let ret = match name { + sym::all => sub_cfgs.fold(Ok(Cfg::True), |x, y| Ok(x? & y?)), + sym::any => sub_cfgs.fold(Ok(Cfg::False), |x, y| Ok(x? | y?)), + sym::not => { + if orig_len == 1 { + let mut sub_cfgs = sub_cfgs.collect::>(); + if sub_cfgs.len() == 1 { + Ok(!sub_cfgs.pop().unwrap()?) + } else { + return Ok(None); + } + } else { + Err(InvalidCfgError { msg: "expected 1 cfg-pattern", span: cfg.span }) + } + } + _ => Err(InvalidCfgError { msg: "invalid predicate", span: cfg.span }), + }; + match ret { + Ok(c) => Ok(Some(c)), + Err(e) => Err(e), + } + } + } + } + + /// Parses a `MetaItem` into a `Cfg`. + /// + /// The `MetaItem` should be the content of the `#[cfg(...)]`, e.g., `unix` or + /// `target_os = "redox"`. + /// + /// If the content is not properly formatted, it will return an error indicating what and where + /// the error is. + pub(crate) fn parse(cfg: &MetaItem) -> Result { + Self::parse_without(cfg, &FxHashSet::default()).map(|ret| ret.unwrap()) + } + + /// Checks whether the given configuration can be matched in the current session. + /// + /// Equivalent to `attr::cfg_matches`. + // FIXME: Actually make use of `features`. + pub(crate) fn matches(&self, parse_sess: &ParseSess, features: Option<&Features>) -> bool { + match *self { + Cfg::False => false, + Cfg::True => true, + Cfg::Not(ref child) => !child.matches(parse_sess, features), + Cfg::All(ref sub_cfgs) => { + sub_cfgs.iter().all(|sub_cfg| sub_cfg.matches(parse_sess, features)) + } + Cfg::Any(ref sub_cfgs) => { + sub_cfgs.iter().any(|sub_cfg| sub_cfg.matches(parse_sess, features)) + } + Cfg::Cfg(name, value) => parse_sess.config.contains(&(name, value)), + } + } + + /// Whether the configuration consists of just `Cfg` or `Not`. + fn is_simple(&self) -> bool { + match *self { + Cfg::False | Cfg::True | Cfg::Cfg(..) | Cfg::Not(..) => true, + Cfg::All(..) | Cfg::Any(..) => false, + } + } + + /// Whether the configuration consists of just `Cfg`, `Not` or `All`. + fn is_all(&self) -> bool { + match *self { + Cfg::False | Cfg::True | Cfg::Cfg(..) | Cfg::Not(..) | Cfg::All(..) => true, + Cfg::Any(..) => false, + } + } + + /// Renders the configuration for human display, as a short HTML description. + pub(crate) fn render_short_html(&self) -> String { + let mut msg = Display(self, Format::ShortHtml).to_string(); + if self.should_capitalize_first_letter() { + if let Some(i) = msg.find(|c: char| c.is_ascii_alphanumeric()) { + msg[i..i + 1].make_ascii_uppercase(); + } + } + msg + } + + /// Renders the configuration for long display, as a long HTML description. + pub(crate) fn render_long_html(&self) -> String { + let on = if self.should_use_with_in_description() { "with" } else { "on" }; + + let mut msg = + format!("Available {on} {}", Display(self, Format::LongHtml)); + if self.should_append_only_to_description() { + msg.push_str(" only"); + } + msg.push('.'); + msg + } + + /// Renders the configuration for long display, as a long plain text description. + pub(crate) fn render_long_plain(&self) -> String { + let on = if self.should_use_with_in_description() { "with" } else { "on" }; + + let mut msg = format!("Available {on} {}", Display(self, Format::LongPlain)); + if self.should_append_only_to_description() { + msg.push_str(" only"); + } + msg + } + + fn should_capitalize_first_letter(&self) -> bool { + match *self { + Cfg::False | Cfg::True | Cfg::Not(..) => true, + Cfg::Any(ref sub_cfgs) | Cfg::All(ref sub_cfgs) => { + sub_cfgs.first().map(Cfg::should_capitalize_first_letter).unwrap_or(false) + } + Cfg::Cfg(name, _) => name == sym::debug_assertions || name == sym::target_endian, + } + } + + fn should_append_only_to_description(&self) -> bool { + match *self { + Cfg::False | Cfg::True => false, + Cfg::Any(..) | Cfg::All(..) | Cfg::Cfg(..) => true, + Cfg::Not(box Cfg::Cfg(..)) => true, + Cfg::Not(..) => false, + } + } + + fn should_use_with_in_description(&self) -> bool { + matches!(self, Cfg::Cfg(sym::target_feature, _)) + } + + /// Attempt to simplify this cfg by assuming that `assume` is already known to be true, will + /// return `None` if simplification managed to completely eliminate any requirements from this + /// `Cfg`. + /// + /// See `tests::test_simplify_with` for examples. + pub(crate) fn simplify_with(&self, assume: &Cfg) -> Option { + if self == assume { + return None; + } + + if let Cfg::All(a) = self { + let mut sub_cfgs: Vec = if let Cfg::All(b) = assume { + a.iter().filter(|a| !b.contains(a)).cloned().collect() + } else { + a.iter().filter(|&a| a != assume).cloned().collect() + }; + let len = sub_cfgs.len(); + return match len { + 0 => None, + 1 => sub_cfgs.pop(), + _ => Some(Cfg::All(sub_cfgs)), + }; + } else if let Cfg::All(b) = assume { + if b.contains(self) { + return None; + } + } + + Some(self.clone()) + } +} + +impl ops::Not for Cfg { + type Output = Cfg; + fn not(self) -> Cfg { + match self { + Cfg::False => Cfg::True, + Cfg::True => Cfg::False, + Cfg::Not(cfg) => *cfg, + s => Cfg::Not(Box::new(s)), + } + } +} + +impl ops::BitAndAssign for Cfg { + fn bitand_assign(&mut self, other: Cfg) { + match (self, other) { + (&mut Cfg::False, _) | (_, Cfg::True) => {} + (s, Cfg::False) => *s = Cfg::False, + (s @ &mut Cfg::True, b) => *s = b, + (&mut Cfg::All(ref mut a), Cfg::All(ref mut b)) => { + for c in b.drain(..) { + if !a.contains(&c) { + a.push(c); + } + } + } + (&mut Cfg::All(ref mut a), ref mut b) => { + if !a.contains(b) { + a.push(mem::replace(b, Cfg::True)); + } + } + (s, Cfg::All(mut a)) => { + let b = mem::replace(s, Cfg::True); + if !a.contains(&b) { + a.push(b); + } + *s = Cfg::All(a); + } + (s, b) => { + if *s != b { + let a = mem::replace(s, Cfg::True); + *s = Cfg::All(vec![a, b]); + } + } + } + } +} + +impl ops::BitAnd for Cfg { + type Output = Cfg; + fn bitand(mut self, other: Cfg) -> Cfg { + self &= other; + self + } +} + +impl ops::BitOrAssign for Cfg { + fn bitor_assign(&mut self, other: Cfg) { + match (self, other) { + (Cfg::True, _) | (_, Cfg::False) | (_, Cfg::True) => {} + (s @ &mut Cfg::False, b) => *s = b, + (&mut Cfg::Any(ref mut a), Cfg::Any(ref mut b)) => { + for c in b.drain(..) { + if !a.contains(&c) { + a.push(c); + } + } + } + (&mut Cfg::Any(ref mut a), ref mut b) => { + if !a.contains(b) { + a.push(mem::replace(b, Cfg::True)); + } + } + (s, Cfg::Any(mut a)) => { + let b = mem::replace(s, Cfg::True); + if !a.contains(&b) { + a.push(b); + } + *s = Cfg::Any(a); + } + (s, b) => { + if *s != b { + let a = mem::replace(s, Cfg::True); + *s = Cfg::Any(vec![a, b]); + } + } + } + } +} + +impl ops::BitOr for Cfg { + type Output = Cfg; + fn bitor(mut self, other: Cfg) -> Cfg { + self |= other; + self + } +} + +#[derive(Clone, Copy)] +enum Format { + LongHtml, + LongPlain, + ShortHtml, +} + +impl Format { + fn is_long(self) -> bool { + match self { + Format::LongHtml | Format::LongPlain => true, + Format::ShortHtml => false, + } + } + + fn is_html(self) -> bool { + match self { + Format::LongHtml | Format::ShortHtml => true, + Format::LongPlain => false, + } + } +} + +/// Pretty-print wrapper for a `Cfg`. Also indicates what form of rendering should be used. +struct Display<'a>(&'a Cfg, Format); + +fn write_with_opt_paren( + fmt: &mut fmt::Formatter<'_>, + has_paren: bool, + obj: T, +) -> fmt::Result { + if has_paren { + fmt.write_char('(')?; + } + obj.fmt(fmt)?; + if has_paren { + fmt.write_char(')')?; + } + Ok(()) +} + +impl<'a> fmt::Display for Display<'a> { + fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { + match *self.0 { + Cfg::Not(ref child) => match **child { + Cfg::Any(ref sub_cfgs) => { + let separator = + if sub_cfgs.iter().all(Cfg::is_simple) { " nor " } else { ", nor " }; + for (i, sub_cfg) in sub_cfgs.iter().enumerate() { + fmt.write_str(if i == 0 { "neither " } else { separator })?; + write_with_opt_paren(fmt, !sub_cfg.is_all(), Display(sub_cfg, self.1))?; + } + Ok(()) + } + ref simple @ Cfg::Cfg(..) => write!(fmt, "non-{}", Display(simple, self.1)), + ref c => write!(fmt, "not ({})", Display(c, self.1)), + }, + + Cfg::Any(ref sub_cfgs) => { + let separator = if sub_cfgs.iter().all(Cfg::is_simple) { " or " } else { ", or " }; + + let short_longhand = self.1.is_long() && { + let all_crate_features = sub_cfgs + .iter() + .all(|sub_cfg| matches!(sub_cfg, Cfg::Cfg(sym::feature, Some(_)))); + let all_target_features = sub_cfgs + .iter() + .all(|sub_cfg| matches!(sub_cfg, Cfg::Cfg(sym::target_feature, Some(_)))); + + if all_crate_features { + fmt.write_str("crate features ")?; + true + } else if all_target_features { + fmt.write_str("target features ")?; + true + } else { + false + } + }; + + for (i, sub_cfg) in sub_cfgs.iter().enumerate() { + if i != 0 { + fmt.write_str(separator)?; + } + if let (true, Cfg::Cfg(_, Some(feat))) = (short_longhand, sub_cfg) { + if self.1.is_html() { + write!(fmt, "{}", feat)?; + } else { + write!(fmt, "`{}`", feat)?; + } + } else { + write_with_opt_paren(fmt, !sub_cfg.is_all(), Display(sub_cfg, self.1))?; + } + } + Ok(()) + } + + Cfg::All(ref sub_cfgs) => { + let short_longhand = self.1.is_long() && { + let all_crate_features = sub_cfgs + .iter() + .all(|sub_cfg| matches!(sub_cfg, Cfg::Cfg(sym::feature, Some(_)))); + let all_target_features = sub_cfgs + .iter() + .all(|sub_cfg| matches!(sub_cfg, Cfg::Cfg(sym::target_feature, Some(_)))); + + if all_crate_features { + fmt.write_str("crate features ")?; + true + } else if all_target_features { + fmt.write_str("target features ")?; + true + } else { + false + } + }; + + for (i, sub_cfg) in sub_cfgs.iter().enumerate() { + if i != 0 { + fmt.write_str(" and ")?; + } + if let (true, Cfg::Cfg(_, Some(feat))) = (short_longhand, sub_cfg) { + if self.1.is_html() { + write!(fmt, "{}", feat)?; + } else { + write!(fmt, "`{}`", feat)?; + } + } else { + write_with_opt_paren(fmt, !sub_cfg.is_simple(), Display(sub_cfg, self.1))?; + } + } + Ok(()) + } + + Cfg::True => fmt.write_str("everywhere"), + Cfg::False => fmt.write_str("nowhere"), + + Cfg::Cfg(name, value) => { + let human_readable = match (name, value) { + (sym::unix, None) => "Unix", + (sym::windows, None) => "Windows", + (sym::debug_assertions, None) => "debug-assertions enabled", + (sym::target_os, Some(os)) => match os.as_str() { + "android" => "Android", + "dragonfly" => "DragonFly BSD", + "emscripten" => "Emscripten", + "freebsd" => "FreeBSD", + "fuchsia" => "Fuchsia", + "haiku" => "Haiku", + "hermit" => "HermitCore", + "illumos" => "illumos", + "ios" => "iOS", + "l4re" => "L4Re", + "linux" => "Linux", + "macos" => "macOS", + "netbsd" => "NetBSD", + "openbsd" => "OpenBSD", + "redox" => "Redox", + "solaris" => "Solaris", + "wasi" => "WASI", + "windows" => "Windows", + _ => "", + }, + (sym::target_arch, Some(arch)) => match arch.as_str() { + "aarch64" => "AArch64", + "arm" => "ARM", + "asmjs" => "JavaScript", + "m68k" => "M68k", + "mips" => "MIPS", + "mips64" => "MIPS-64", + "msp430" => "MSP430", + "powerpc" => "PowerPC", + "powerpc64" => "PowerPC-64", + "riscv32" => "RISC-V RV32", + "riscv64" => "RISC-V RV64", + "s390x" => "s390x", + "sparc64" => "SPARC64", + "wasm32" | "wasm64" => "WebAssembly", + "x86" => "x86", + "x86_64" => "x86-64", + _ => "", + }, + (sym::target_vendor, Some(vendor)) => match vendor.as_str() { + "apple" => "Apple", + "pc" => "PC", + "sun" => "Sun", + "fortanix" => "Fortanix", + _ => "", + }, + (sym::target_env, Some(env)) => match env.as_str() { + "gnu" => "GNU", + "msvc" => "MSVC", + "musl" => "musl", + "newlib" => "Newlib", + "uclibc" => "uClibc", + "sgx" => "SGX", + _ => "", + }, + (sym::target_endian, Some(endian)) => return write!(fmt, "{}-endian", endian), + (sym::target_pointer_width, Some(bits)) => return write!(fmt, "{}-bit", bits), + (sym::target_feature, Some(feat)) => match self.1 { + Format::LongHtml => { + return write!(fmt, "target feature {}", feat); + } + Format::LongPlain => return write!(fmt, "target feature `{}`", feat), + Format::ShortHtml => return write!(fmt, "{}", feat), + }, + (sym::feature, Some(feat)) => match self.1 { + Format::LongHtml => { + return write!(fmt, "crate feature {}", feat); + } + Format::LongPlain => return write!(fmt, "crate feature `{}`", feat), + Format::ShortHtml => return write!(fmt, "{}", feat), + }, + _ => "", + }; + if !human_readable.is_empty() { + fmt.write_str(human_readable) + } else if let Some(v) = value { + if self.1.is_html() { + write!( + fmt, + r#"{}="{}""#, + Escape(name.as_str()), + Escape(v.as_str()) + ) + } else { + write!(fmt, r#"`{}="{}"`"#, name, v) + } + } else if self.1.is_html() { + write!(fmt, "{}", Escape(name.as_str())) + } else { + write!(fmt, "`{}`", name) + } + } + } + } +} diff --git a/src/librustdoc/clean/cfg/tests.rs b/src/librustdoc/clean/cfg/tests.rs new file mode 100644 index 000000000..7f72d5d39 --- /dev/null +++ b/src/librustdoc/clean/cfg/tests.rs @@ -0,0 +1,467 @@ +use super::*; + +use rustc_ast::attr; +use rustc_ast::Path; +use rustc_span::create_default_session_globals_then; +use rustc_span::symbol::{Ident, Symbol}; +use rustc_span::DUMMY_SP; + +fn word_cfg(s: &str) -> Cfg { + Cfg::Cfg(Symbol::intern(s), None) +} + +fn name_value_cfg(name: &str, value: &str) -> Cfg { + Cfg::Cfg(Symbol::intern(name), Some(Symbol::intern(value))) +} + +fn dummy_meta_item_word(name: &str) -> MetaItem { + MetaItem { + path: Path::from_ident(Ident::from_str(name)), + kind: MetaItemKind::Word, + span: DUMMY_SP, + } +} + +macro_rules! dummy_meta_item_list { + ($name:ident, [$($list:ident),* $(,)?]) => { + MetaItem { + path: Path::from_ident(Ident::from_str(stringify!($name))), + kind: MetaItemKind::List(vec![ + $( + NestedMetaItem::MetaItem( + dummy_meta_item_word(stringify!($list)), + ), + )* + ]), + span: DUMMY_SP, + } + }; + + ($name:ident, [$($list:expr),* $(,)?]) => { + MetaItem { + path: Path::from_ident(Ident::from_str(stringify!($name))), + kind: MetaItemKind::List(vec![ + $( + NestedMetaItem::MetaItem($list), + )* + ]), + span: DUMMY_SP, + } + }; +} + +#[test] +fn test_cfg_not() { + create_default_session_globals_then(|| { + assert_eq!(!Cfg::False, Cfg::True); + assert_eq!(!Cfg::True, Cfg::False); + assert_eq!(!word_cfg("test"), Cfg::Not(Box::new(word_cfg("test")))); + assert_eq!( + !Cfg::All(vec![word_cfg("a"), word_cfg("b")]), + Cfg::Not(Box::new(Cfg::All(vec![word_cfg("a"), word_cfg("b")]))) + ); + assert_eq!( + !Cfg::Any(vec![word_cfg("a"), word_cfg("b")]), + Cfg::Not(Box::new(Cfg::Any(vec![word_cfg("a"), word_cfg("b")]))) + ); + assert_eq!(!Cfg::Not(Box::new(word_cfg("test"))), word_cfg("test")); + }) +} + +#[test] +fn test_cfg_and() { + create_default_session_globals_then(|| { + let mut x = Cfg::False; + x &= Cfg::True; + assert_eq!(x, Cfg::False); + + x = word_cfg("test"); + x &= Cfg::False; + assert_eq!(x, Cfg::False); + + x = word_cfg("test2"); + x &= Cfg::True; + assert_eq!(x, word_cfg("test2")); + + x = Cfg::True; + x &= word_cfg("test3"); + assert_eq!(x, word_cfg("test3")); + + x &= word_cfg("test3"); + assert_eq!(x, word_cfg("test3")); + + x &= word_cfg("test4"); + assert_eq!(x, Cfg::All(vec![word_cfg("test3"), word_cfg("test4")])); + + x &= word_cfg("test4"); + assert_eq!(x, Cfg::All(vec![word_cfg("test3"), word_cfg("test4")])); + + x &= word_cfg("test5"); + assert_eq!(x, Cfg::All(vec![word_cfg("test3"), word_cfg("test4"), word_cfg("test5")])); + + x &= Cfg::All(vec![word_cfg("test6"), word_cfg("test7")]); + assert_eq!( + x, + Cfg::All(vec![ + word_cfg("test3"), + word_cfg("test4"), + word_cfg("test5"), + word_cfg("test6"), + word_cfg("test7"), + ]) + ); + + x &= Cfg::All(vec![word_cfg("test6"), word_cfg("test7")]); + assert_eq!( + x, + Cfg::All(vec![ + word_cfg("test3"), + word_cfg("test4"), + word_cfg("test5"), + word_cfg("test6"), + word_cfg("test7"), + ]) + ); + + let mut y = Cfg::Any(vec![word_cfg("a"), word_cfg("b")]); + y &= x; + assert_eq!( + y, + Cfg::All(vec![ + word_cfg("test3"), + word_cfg("test4"), + word_cfg("test5"), + word_cfg("test6"), + word_cfg("test7"), + Cfg::Any(vec![word_cfg("a"), word_cfg("b")]), + ]) + ); + + let mut z = word_cfg("test8"); + z &= Cfg::All(vec![word_cfg("test9"), word_cfg("test10")]); + assert_eq!(z, Cfg::All(vec![word_cfg("test9"), word_cfg("test10"), word_cfg("test8")])); + + let mut z = word_cfg("test11"); + z &= Cfg::All(vec![word_cfg("test11"), word_cfg("test12")]); + assert_eq!(z, Cfg::All(vec![word_cfg("test11"), word_cfg("test12")])); + + assert_eq!( + word_cfg("a") & word_cfg("b") & word_cfg("c"), + Cfg::All(vec![word_cfg("a"), word_cfg("b"), word_cfg("c")]) + ); + }) +} + +#[test] +fn test_cfg_or() { + create_default_session_globals_then(|| { + let mut x = Cfg::True; + x |= Cfg::False; + assert_eq!(x, Cfg::True); + + x = word_cfg("test"); + x |= Cfg::True; + assert_eq!(x, word_cfg("test")); + + x = word_cfg("test2"); + x |= Cfg::False; + assert_eq!(x, word_cfg("test2")); + + x = Cfg::False; + x |= word_cfg("test3"); + assert_eq!(x, word_cfg("test3")); + + x |= word_cfg("test3"); + assert_eq!(x, word_cfg("test3")); + + x |= word_cfg("test4"); + assert_eq!(x, Cfg::Any(vec![word_cfg("test3"), word_cfg("test4")])); + + x |= word_cfg("test4"); + assert_eq!(x, Cfg::Any(vec![word_cfg("test3"), word_cfg("test4")])); + + x |= word_cfg("test5"); + assert_eq!(x, Cfg::Any(vec![word_cfg("test3"), word_cfg("test4"), word_cfg("test5")])); + + x |= Cfg::Any(vec![word_cfg("test6"), word_cfg("test7")]); + assert_eq!( + x, + Cfg::Any(vec![ + word_cfg("test3"), + word_cfg("test4"), + word_cfg("test5"), + word_cfg("test6"), + word_cfg("test7"), + ]) + ); + + x |= Cfg::Any(vec![word_cfg("test6"), word_cfg("test7")]); + assert_eq!( + x, + Cfg::Any(vec![ + word_cfg("test3"), + word_cfg("test4"), + word_cfg("test5"), + word_cfg("test6"), + word_cfg("test7"), + ]) + ); + + let mut y = Cfg::All(vec![word_cfg("a"), word_cfg("b")]); + y |= x; + assert_eq!( + y, + Cfg::Any(vec![ + word_cfg("test3"), + word_cfg("test4"), + word_cfg("test5"), + word_cfg("test6"), + word_cfg("test7"), + Cfg::All(vec![word_cfg("a"), word_cfg("b")]), + ]) + ); + + let mut z = word_cfg("test8"); + z |= Cfg::Any(vec![word_cfg("test9"), word_cfg("test10")]); + assert_eq!(z, Cfg::Any(vec![word_cfg("test9"), word_cfg("test10"), word_cfg("test8")])); + + let mut z = word_cfg("test11"); + z |= Cfg::Any(vec![word_cfg("test11"), word_cfg("test12")]); + assert_eq!(z, Cfg::Any(vec![word_cfg("test11"), word_cfg("test12")])); + + assert_eq!( + word_cfg("a") | word_cfg("b") | word_cfg("c"), + Cfg::Any(vec![word_cfg("a"), word_cfg("b"), word_cfg("c")]) + ); + }) +} + +#[test] +fn test_parse_ok() { + create_default_session_globals_then(|| { + let mi = dummy_meta_item_word("all"); + assert_eq!(Cfg::parse(&mi), Ok(word_cfg("all"))); + + let mi = + attr::mk_name_value_item_str(Ident::from_str("all"), Symbol::intern("done"), DUMMY_SP); + assert_eq!(Cfg::parse(&mi), Ok(name_value_cfg("all", "done"))); + + let mi = dummy_meta_item_list!(all, [a, b]); + assert_eq!(Cfg::parse(&mi), Ok(word_cfg("a") & word_cfg("b"))); + + let mi = dummy_meta_item_list!(any, [a, b]); + assert_eq!(Cfg::parse(&mi), Ok(word_cfg("a") | word_cfg("b"))); + + let mi = dummy_meta_item_list!(not, [a]); + assert_eq!(Cfg::parse(&mi), Ok(!word_cfg("a"))); + + let mi = dummy_meta_item_list!( + not, + [dummy_meta_item_list!( + any, + [dummy_meta_item_word("a"), dummy_meta_item_list!(all, [b, c]),] + ),] + ); + assert_eq!(Cfg::parse(&mi), Ok(!(word_cfg("a") | (word_cfg("b") & word_cfg("c"))))); + + let mi = dummy_meta_item_list!(all, [a, b, c]); + assert_eq!(Cfg::parse(&mi), Ok(word_cfg("a") & word_cfg("b") & word_cfg("c"))); + }) +} + +#[test] +fn test_parse_err() { + create_default_session_globals_then(|| { + let mi = attr::mk_name_value_item(Ident::from_str("foo"), LitKind::Bool(false), DUMMY_SP); + assert!(Cfg::parse(&mi).is_err()); + + let mi = dummy_meta_item_list!(not, [a, b]); + assert!(Cfg::parse(&mi).is_err()); + + let mi = dummy_meta_item_list!(not, []); + assert!(Cfg::parse(&mi).is_err()); + + let mi = dummy_meta_item_list!(foo, []); + assert!(Cfg::parse(&mi).is_err()); + + let mi = dummy_meta_item_list!( + all, + [dummy_meta_item_list!(foo, []), dummy_meta_item_word("b"),] + ); + assert!(Cfg::parse(&mi).is_err()); + + let mi = dummy_meta_item_list!( + any, + [dummy_meta_item_word("a"), dummy_meta_item_list!(foo, []),] + ); + assert!(Cfg::parse(&mi).is_err()); + + let mi = dummy_meta_item_list!(not, [dummy_meta_item_list!(foo, []),]); + assert!(Cfg::parse(&mi).is_err()); + }) +} + +#[test] +fn test_render_short_html() { + create_default_session_globals_then(|| { + assert_eq!(word_cfg("unix").render_short_html(), "Unix"); + assert_eq!(name_value_cfg("target_os", "macos").render_short_html(), "macOS"); + assert_eq!(name_value_cfg("target_pointer_width", "16").render_short_html(), "16-bit"); + assert_eq!(name_value_cfg("target_endian", "little").render_short_html(), "Little-endian"); + assert_eq!((!word_cfg("windows")).render_short_html(), "Non-Windows"); + assert_eq!( + (word_cfg("unix") & word_cfg("windows")).render_short_html(), + "Unix and Windows" + ); + assert_eq!((word_cfg("unix") | word_cfg("windows")).render_short_html(), "Unix or Windows"); + assert_eq!( + (word_cfg("unix") & word_cfg("windows") & word_cfg("debug_assertions")) + .render_short_html(), + "Unix and Windows and debug-assertions enabled" + ); + assert_eq!( + (word_cfg("unix") | word_cfg("windows") | word_cfg("debug_assertions")) + .render_short_html(), + "Unix or Windows or debug-assertions enabled" + ); + assert_eq!( + (!(word_cfg("unix") | word_cfg("windows") | word_cfg("debug_assertions"))) + .render_short_html(), + "Neither Unix nor Windows nor debug-assertions enabled" + ); + assert_eq!( + ((word_cfg("unix") & name_value_cfg("target_arch", "x86_64")) + | (word_cfg("windows") & name_value_cfg("target_pointer_width", "64"))) + .render_short_html(), + "Unix and x86-64, or Windows and 64-bit" + ); + assert_eq!( + (!(word_cfg("unix") & word_cfg("windows"))).render_short_html(), + "Not (Unix and Windows)" + ); + assert_eq!( + ((word_cfg("debug_assertions") | word_cfg("windows")) & word_cfg("unix")) + .render_short_html(), + "(Debug-assertions enabled or Windows) and Unix" + ); + assert_eq!( + name_value_cfg("target_feature", "sse2").render_short_html(), + "sse2" + ); + assert_eq!( + (name_value_cfg("target_arch", "x86_64") & name_value_cfg("target_feature", "sse2")) + .render_short_html(), + "x86-64 and sse2" + ); + }) +} + +#[test] +fn test_render_long_html() { + create_default_session_globals_then(|| { + assert_eq!(word_cfg("unix").render_long_html(), "Available on Unix only."); + assert_eq!( + name_value_cfg("target_os", "macos").render_long_html(), + "Available on macOS only." + ); + assert_eq!( + name_value_cfg("target_os", "wasi").render_long_html(), + "Available on WASI only." + ); + assert_eq!( + name_value_cfg("target_pointer_width", "16").render_long_html(), + "Available on 16-bit only." + ); + assert_eq!( + name_value_cfg("target_endian", "little").render_long_html(), + "Available on little-endian only." + ); + assert_eq!( + (!word_cfg("windows")).render_long_html(), + "Available on non-Windows only." + ); + assert_eq!( + (word_cfg("unix") & word_cfg("windows")).render_long_html(), + "Available on Unix and Windows only." + ); + assert_eq!( + (word_cfg("unix") | word_cfg("windows")).render_long_html(), + "Available on Unix or Windows only." + ); + assert_eq!( + (word_cfg("unix") & word_cfg("windows") & word_cfg("debug_assertions")) + .render_long_html(), + "Available on Unix and Windows and debug-assertions enabled only." + ); + assert_eq!( + (word_cfg("unix") | word_cfg("windows") | word_cfg("debug_assertions")) + .render_long_html(), + "Available on Unix or Windows or debug-assertions enabled only." + ); + assert_eq!( + (!(word_cfg("unix") | word_cfg("windows") | word_cfg("debug_assertions"))) + .render_long_html(), + "Available on neither Unix nor Windows nor debug-assertions enabled." + ); + assert_eq!( + ((word_cfg("unix") & name_value_cfg("target_arch", "x86_64")) + | (word_cfg("windows") & name_value_cfg("target_pointer_width", "64"))) + .render_long_html(), + "Available on Unix and x86-64, or Windows and 64-bit only." + ); + assert_eq!( + (!(word_cfg("unix") & word_cfg("windows"))).render_long_html(), + "Available on not (Unix and Windows)." + ); + assert_eq!( + ((word_cfg("debug_assertions") | word_cfg("windows")) & word_cfg("unix")) + .render_long_html(), + "Available on (debug-assertions enabled or Windows) and Unix only." + ); + assert_eq!( + name_value_cfg("target_feature", "sse2").render_long_html(), + "Available with target feature sse2 only." + ); + assert_eq!( + (name_value_cfg("target_arch", "x86_64") & name_value_cfg("target_feature", "sse2")) + .render_long_html(), + "Available on x86-64 and target feature sse2 only." + ); + }) +} + +#[test] +fn test_simplify_with() { + // This is a tiny subset of things that could be simplified, but it likely covers 90% of + // real world usecases well. + create_default_session_globals_then(|| { + let foo = word_cfg("foo"); + let bar = word_cfg("bar"); + let baz = word_cfg("baz"); + let quux = word_cfg("quux"); + + let foobar = Cfg::All(vec![foo.clone(), bar.clone()]); + let barbaz = Cfg::All(vec![bar.clone(), baz.clone()]); + let foobarbaz = Cfg::All(vec![foo.clone(), bar.clone(), baz.clone()]); + let bazquux = Cfg::All(vec![baz.clone(), quux.clone()]); + + // Unrelated cfgs don't affect each other + assert_eq!(foo.simplify_with(&bar).as_ref(), Some(&foo)); + assert_eq!(foobar.simplify_with(&bazquux).as_ref(), Some(&foobar)); + + // Identical cfgs are eliminated + assert_eq!(foo.simplify_with(&foo), None); + assert_eq!(foobar.simplify_with(&foobar), None); + + // Multiple cfgs eliminate a single assumed cfg + assert_eq!(foobar.simplify_with(&foo).as_ref(), Some(&bar)); + assert_eq!(foobar.simplify_with(&bar).as_ref(), Some(&foo)); + + // A single cfg is eliminated by multiple assumed cfg containing it + assert_eq!(foo.simplify_with(&foobar), None); + + // Multiple cfgs eliminate the matching subset of multiple assumed cfg + assert_eq!(foobar.simplify_with(&barbaz).as_ref(), Some(&foo)); + assert_eq!(foobar.simplify_with(&foobarbaz), None); + }); +} diff --git a/src/librustdoc/clean/inline.rs b/src/librustdoc/clean/inline.rs new file mode 100644 index 000000000..58d0aedb0 --- /dev/null +++ b/src/librustdoc/clean/inline.rs @@ -0,0 +1,727 @@ +//! Support for inlining external documentation into the current AST. + +use std::iter::once; +use std::sync::Arc; + +use rustc_ast as ast; +use rustc_data_structures::fx::FxHashSet; +use rustc_data_structures::thin_vec::ThinVec; +use rustc_hir as hir; +use rustc_hir::def::{DefKind, Res}; +use rustc_hir::def_id::DefId; +use rustc_hir::Mutability; +use rustc_metadata::creader::{CStore, LoadedMacro}; +use rustc_middle::ty::{self, TyCtxt}; +use rustc_span::hygiene::MacroKind; +use rustc_span::symbol::{kw, sym, Symbol}; + +use crate::clean::{ + self, clean_fn_decl_from_did_and_sig, clean_middle_field, clean_middle_ty, + clean_trait_ref_with_bindings, clean_ty, clean_ty_generics, clean_variant_def, + clean_visibility, utils, Attributes, AttributesExt, Clean, ImplKind, ItemId, Type, Visibility, +}; +use crate::core::DocContext; +use crate::formats::item_type::ItemType; + +type Attrs<'hir> = &'hir [ast::Attribute]; + +/// Attempt to inline a definition into this AST. +/// +/// This function will fetch the definition specified, and if it is +/// from another crate it will attempt to inline the documentation +/// from the other crate into this crate. +/// +/// This is primarily used for `pub use` statements which are, in general, +/// implementation details. Inlining the documentation should help provide a +/// better experience when reading the documentation in this use case. +/// +/// The returned value is `None` if the definition could not be inlined, +/// and `Some` of a vector of items if it was successfully expanded. +/// +/// `parent_module` refers to the parent of the *re-export*, not the original item. +pub(crate) fn try_inline( + cx: &mut DocContext<'_>, + parent_module: DefId, + import_def_id: Option, + res: Res, + name: Symbol, + attrs: Option>, + visited: &mut FxHashSet, +) -> Option> { + let did = res.opt_def_id()?; + if did.is_local() { + return None; + } + let mut ret = Vec::new(); + + debug!("attrs={:?}", attrs); + let attrs_clone = attrs; + + let kind = match res { + Res::Def(DefKind::Trait, did) => { + record_extern_fqn(cx, did, ItemType::Trait); + build_impls(cx, Some(parent_module), did, attrs, &mut ret); + clean::TraitItem(build_external_trait(cx, did)) + } + Res::Def(DefKind::Fn, did) => { + record_extern_fqn(cx, did, ItemType::Function); + clean::FunctionItem(build_external_function(cx, did)) + } + Res::Def(DefKind::Struct, did) => { + record_extern_fqn(cx, did, ItemType::Struct); + build_impls(cx, Some(parent_module), did, attrs, &mut ret); + clean::StructItem(build_struct(cx, did)) + } + Res::Def(DefKind::Union, did) => { + record_extern_fqn(cx, did, ItemType::Union); + build_impls(cx, Some(parent_module), did, attrs, &mut ret); + clean::UnionItem(build_union(cx, did)) + } + Res::Def(DefKind::TyAlias, did) => { + record_extern_fqn(cx, did, ItemType::Typedef); + build_impls(cx, Some(parent_module), did, attrs, &mut ret); + clean::TypedefItem(build_type_alias(cx, did)) + } + Res::Def(DefKind::Enum, did) => { + record_extern_fqn(cx, did, ItemType::Enum); + build_impls(cx, Some(parent_module), did, attrs, &mut ret); + clean::EnumItem(build_enum(cx, did)) + } + Res::Def(DefKind::ForeignTy, did) => { + record_extern_fqn(cx, did, ItemType::ForeignType); + build_impls(cx, Some(parent_module), did, attrs, &mut ret); + clean::ForeignTypeItem + } + // Never inline enum variants but leave them shown as re-exports. + Res::Def(DefKind::Variant, _) => return None, + // Assume that enum variants and struct types are re-exported next to + // their constructors. + Res::Def(DefKind::Ctor(..), _) | Res::SelfCtor(..) => return Some(Vec::new()), + Res::Def(DefKind::Mod, did) => { + record_extern_fqn(cx, did, ItemType::Module); + clean::ModuleItem(build_module(cx, did, visited)) + } + Res::Def(DefKind::Static(_), did) => { + record_extern_fqn(cx, did, ItemType::Static); + clean::StaticItem(build_static(cx, did, cx.tcx.is_mutable_static(did))) + } + Res::Def(DefKind::Const, did) => { + record_extern_fqn(cx, did, ItemType::Constant); + clean::ConstantItem(build_const(cx, did)) + } + Res::Def(DefKind::Macro(kind), did) => { + let mac = build_macro(cx, did, name, import_def_id); + + let type_kind = match kind { + MacroKind::Bang => ItemType::Macro, + MacroKind::Attr => ItemType::ProcAttribute, + MacroKind::Derive => ItemType::ProcDerive, + }; + record_extern_fqn(cx, did, type_kind); + mac + } + _ => return None, + }; + + let (attrs, cfg) = merge_attrs(cx, Some(parent_module), load_attrs(cx, did), attrs_clone); + cx.inlined.insert(did.into()); + let mut item = clean::Item::from_def_id_and_attrs_and_parts( + did, + Some(name), + kind, + Box::new(attrs), + cx, + cfg, + ); + if let Some(import_def_id) = import_def_id { + // The visibility needs to reflect the one from the reexport and not from the "source" DefId. + item.visibility = clean_visibility(cx.tcx.visibility(import_def_id)); + } + ret.push(item); + Some(ret) +} + +pub(crate) fn try_inline_glob( + cx: &mut DocContext<'_>, + res: Res, + visited: &mut FxHashSet, + inlined_names: &mut FxHashSet<(ItemType, Symbol)>, +) -> Option> { + let did = res.opt_def_id()?; + if did.is_local() { + return None; + } + + match res { + Res::Def(DefKind::Mod, did) => { + let mut items = build_module_items(cx, did, visited, inlined_names); + items.drain_filter(|item| { + if let Some(name) = item.name { + // If an item with the same type and name already exists, + // it takes priority over the inlined stuff. + !inlined_names.insert((item.type_(), name)) + } else { + false + } + }); + Some(items) + } + // glob imports on things like enums aren't inlined even for local exports, so just bail + _ => None, + } +} + +pub(crate) fn load_attrs<'hir>(cx: &DocContext<'hir>, did: DefId) -> Attrs<'hir> { + cx.tcx.get_attrs_unchecked(did) +} + +/// Record an external fully qualified name in the external_paths cache. +/// +/// These names are used later on by HTML rendering to generate things like +/// source links back to the original item. +pub(crate) fn record_extern_fqn(cx: &mut DocContext<'_>, did: DefId, kind: ItemType) { + let crate_name = cx.tcx.crate_name(did.krate); + + let relative = + cx.tcx.def_path(did).data.into_iter().filter_map(|elem| elem.data.get_opt_name()); + let fqn = if let ItemType::Macro = kind { + // Check to see if it is a macro 2.0 or built-in macro + if matches!( + CStore::from_tcx(cx.tcx).load_macro_untracked(did, cx.sess()), + LoadedMacro::MacroDef(def, _) + if matches!(&def.kind, ast::ItemKind::MacroDef(ast_def) + if !ast_def.macro_rules) + ) { + once(crate_name).chain(relative).collect() + } else { + vec![crate_name, relative.last().expect("relative was empty")] + } + } else { + once(crate_name).chain(relative).collect() + }; + + if did.is_local() { + cx.cache.exact_paths.insert(did, fqn); + } else { + cx.cache.external_paths.insert(did, (fqn, kind)); + } +} + +pub(crate) fn build_external_trait(cx: &mut DocContext<'_>, did: DefId) -> clean::Trait { + let trait_items = cx + .tcx + .associated_items(did) + .in_definition_order() + .map(|item| { + // When building an external trait, the cleaned trait will have all items public, + // which causes methods to have a `pub` prefix, which is invalid since items in traits + // can not have a visibility prefix. Thus we override the visibility here manually. + // See https://github.com/rust-lang/rust/issues/81274 + clean::Item { visibility: Visibility::Inherited, ..item.clean(cx) } + }) + .collect(); + + let predicates = cx.tcx.predicates_of(did); + let generics = clean_ty_generics(cx, cx.tcx.generics_of(did), predicates); + let generics = filter_non_trait_generics(did, generics); + let (generics, supertrait_bounds) = separate_supertrait_bounds(generics); + clean::Trait { def_id: did, generics, items: trait_items, bounds: supertrait_bounds } +} + +fn build_external_function<'tcx>(cx: &mut DocContext<'tcx>, did: DefId) -> Box { + let sig = cx.tcx.fn_sig(did); + + let predicates = cx.tcx.predicates_of(did); + let (generics, decl) = clean::enter_impl_trait(cx, |cx| { + // NOTE: generics need to be cleaned before the decl! + let generics = clean_ty_generics(cx, cx.tcx.generics_of(did), predicates); + let decl = clean_fn_decl_from_did_and_sig(cx, Some(did), sig); + (generics, decl) + }); + Box::new(clean::Function { decl, generics }) +} + +fn build_enum(cx: &mut DocContext<'_>, did: DefId) -> clean::Enum { + let predicates = cx.tcx.explicit_predicates_of(did); + + clean::Enum { + generics: clean_ty_generics(cx, cx.tcx.generics_of(did), predicates), + variants: cx.tcx.adt_def(did).variants().iter().map(|v| clean_variant_def(v, cx)).collect(), + } +} + +fn build_struct(cx: &mut DocContext<'_>, did: DefId) -> clean::Struct { + let predicates = cx.tcx.explicit_predicates_of(did); + let variant = cx.tcx.adt_def(did).non_enum_variant(); + + clean::Struct { + struct_type: variant.ctor_kind, + generics: clean_ty_generics(cx, cx.tcx.generics_of(did), predicates), + fields: variant.fields.iter().map(|x| clean_middle_field(x, cx)).collect(), + } +} + +fn build_union(cx: &mut DocContext<'_>, did: DefId) -> clean::Union { + let predicates = cx.tcx.explicit_predicates_of(did); + let variant = cx.tcx.adt_def(did).non_enum_variant(); + + let generics = clean_ty_generics(cx, cx.tcx.generics_of(did), predicates); + let fields = variant.fields.iter().map(|x| clean_middle_field(x, cx)).collect(); + clean::Union { generics, fields } +} + +fn build_type_alias(cx: &mut DocContext<'_>, did: DefId) -> Box { + let predicates = cx.tcx.explicit_predicates_of(did); + let type_ = clean_middle_ty(cx.tcx.type_of(did), cx, Some(did)); + + Box::new(clean::Typedef { + type_, + generics: clean_ty_generics(cx, cx.tcx.generics_of(did), predicates), + item_type: None, + }) +} + +/// Builds all inherent implementations of an ADT (struct/union/enum) or Trait item/path/reexport. +pub(crate) fn build_impls( + cx: &mut DocContext<'_>, + parent_module: Option, + did: DefId, + attrs: Option>, + ret: &mut Vec, +) { + let _prof_timer = cx.tcx.sess.prof.generic_activity("build_inherent_impls"); + let tcx = cx.tcx; + + // for each implementation of an item represented by `did`, build the clean::Item for that impl + for &did in tcx.inherent_impls(did).iter() { + build_impl(cx, parent_module, did, attrs, ret); + } +} + +/// `parent_module` refers to the parent of the re-export, not the original item +fn merge_attrs( + cx: &mut DocContext<'_>, + parent_module: Option, + old_attrs: Attrs<'_>, + new_attrs: Option>, +) -> (clean::Attributes, Option>) { + // NOTE: If we have additional attributes (from a re-export), + // always insert them first. This ensure that re-export + // doc comments show up before the original doc comments + // when we render them. + if let Some(inner) = new_attrs { + let mut both = inner.to_vec(); + both.extend_from_slice(old_attrs); + ( + if let Some(new_id) = parent_module { + Attributes::from_ast_with_additional(old_attrs, (inner, new_id)) + } else { + Attributes::from_ast(&both) + }, + both.cfg(cx.tcx, &cx.cache.hidden_cfg), + ) + } else { + (Attributes::from_ast(&old_attrs), old_attrs.cfg(cx.tcx, &cx.cache.hidden_cfg)) + } +} + +/// Inline an `impl`, inherent or of a trait. The `did` must be for an `impl`. +pub(crate) fn build_impl( + cx: &mut DocContext<'_>, + parent_module: Option, + did: DefId, + attrs: Option>, + ret: &mut Vec, +) { + if !cx.inlined.insert(did.into()) { + return; + } + + let _prof_timer = cx.tcx.sess.prof.generic_activity("build_impl"); + + let tcx = cx.tcx; + let associated_trait = tcx.impl_trait_ref(did); + + // Only inline impl if the implemented trait is + // reachable in rustdoc generated documentation + if !did.is_local() { + if let Some(traitref) = associated_trait { + let did = traitref.def_id; + if !cx.cache.access_levels.is_public(did) { + return; + } + + if let Some(stab) = tcx.lookup_stability(did) { + if stab.is_unstable() && stab.feature == sym::rustc_private { + return; + } + } + } + } + + let impl_item = match did.as_local() { + Some(did) => match &tcx.hir().expect_item(did).kind { + hir::ItemKind::Impl(impl_) => Some(impl_), + _ => panic!("`DefID` passed to `build_impl` is not an `impl"), + }, + None => None, + }; + + let for_ = match &impl_item { + Some(impl_) => clean_ty(impl_.self_ty, cx), + None => clean_middle_ty(tcx.type_of(did), cx, Some(did)), + }; + + // Only inline impl if the implementing type is + // reachable in rustdoc generated documentation + if !did.is_local() { + if let Some(did) = for_.def_id(&cx.cache) { + if !cx.cache.access_levels.is_public(did) { + return; + } + + if let Some(stab) = tcx.lookup_stability(did) { + if stab.is_unstable() && stab.feature == sym::rustc_private { + return; + } + } + } + } + + let document_hidden = cx.render_options.document_hidden; + let predicates = tcx.explicit_predicates_of(did); + let (trait_items, generics) = match impl_item { + Some(impl_) => ( + impl_ + .items + .iter() + .map(|item| tcx.hir().impl_item(item.id)) + .filter(|item| { + // Filter out impl items whose corresponding trait item has `doc(hidden)` + // not to document such impl items. + // For inherent impls, we don't do any filtering, because that's already done in strip_hidden.rs. + + // When `--document-hidden-items` is passed, we don't + // do any filtering, too. + if document_hidden { + return true; + } + if let Some(associated_trait) = associated_trait { + let assoc_kind = match item.kind { + hir::ImplItemKind::Const(..) => ty::AssocKind::Const, + hir::ImplItemKind::Fn(..) => ty::AssocKind::Fn, + hir::ImplItemKind::TyAlias(..) => ty::AssocKind::Type, + }; + let trait_item = tcx + .associated_items(associated_trait.def_id) + .find_by_name_and_kind( + tcx, + item.ident, + assoc_kind, + associated_trait.def_id, + ) + .unwrap(); // SAFETY: For all impl items there exists trait item that has the same name. + !tcx.is_doc_hidden(trait_item.def_id) + } else { + true + } + }) + .map(|item| item.clean(cx)) + .collect::>(), + impl_.generics.clean(cx), + ), + None => ( + tcx.associated_items(did) + .in_definition_order() + .filter(|item| { + // If this is a trait impl, filter out associated items whose corresponding item + // in the associated trait is marked `doc(hidden)`. + // If this is an inherent impl, filter out private associated items. + if let Some(associated_trait) = associated_trait { + let trait_item = tcx + .associated_items(associated_trait.def_id) + .find_by_name_and_kind( + tcx, + item.ident(tcx), + item.kind, + associated_trait.def_id, + ) + .unwrap(); // corresponding associated item has to exist + !tcx.is_doc_hidden(trait_item.def_id) + } else { + item.visibility(tcx).is_public() + } + }) + .map(|item| item.clean(cx)) + .collect::>(), + clean::enter_impl_trait(cx, |cx| { + clean_ty_generics(cx, tcx.generics_of(did), predicates) + }), + ), + }; + let polarity = tcx.impl_polarity(did); + let trait_ = associated_trait.map(|t| clean_trait_ref_with_bindings(cx, t, &[])); + if trait_.as_ref().map(|t| t.def_id()) == tcx.lang_items().deref_trait() { + super::build_deref_target_impls(cx, &trait_items, ret); + } + + // Return if the trait itself or any types of the generic parameters are doc(hidden). + let mut stack: Vec<&Type> = vec![&for_]; + + if let Some(did) = trait_.as_ref().map(|t| t.def_id()) { + if tcx.is_doc_hidden(did) { + return; + } + } + if let Some(generics) = trait_.as_ref().and_then(|t| t.generics()) { + stack.extend(generics); + } + + while let Some(ty) = stack.pop() { + if let Some(did) = ty.def_id(&cx.cache) { + if tcx.is_doc_hidden(did) { + return; + } + } + if let Some(generics) = ty.generics() { + stack.extend(generics); + } + } + + if let Some(did) = trait_.as_ref().map(|t| t.def_id()) { + record_extern_trait(cx, did); + } + + let (merged_attrs, cfg) = merge_attrs(cx, parent_module, load_attrs(cx, did), attrs); + trace!("merged_attrs={:?}", merged_attrs); + + trace!( + "build_impl: impl {:?} for {:?}", + trait_.as_ref().map(|t| t.def_id()), + for_.def_id(&cx.cache) + ); + ret.push(clean::Item::from_def_id_and_attrs_and_parts( + did, + None, + clean::ImplItem(Box::new(clean::Impl { + unsafety: hir::Unsafety::Normal, + generics, + trait_, + for_, + items: trait_items, + polarity, + kind: if utils::has_doc_flag(tcx, did, sym::fake_variadic) { + ImplKind::FakeVaradic + } else { + ImplKind::Normal + }, + })), + Box::new(merged_attrs), + cx, + cfg, + )); +} + +fn build_module( + cx: &mut DocContext<'_>, + did: DefId, + visited: &mut FxHashSet, +) -> clean::Module { + let items = build_module_items(cx, did, visited, &mut FxHashSet::default()); + + let span = clean::Span::new(cx.tcx.def_span(did)); + clean::Module { items, span } +} + +fn build_module_items( + cx: &mut DocContext<'_>, + did: DefId, + visited: &mut FxHashSet, + inlined_names: &mut FxHashSet<(ItemType, Symbol)>, +) -> Vec { + let mut items = Vec::new(); + + // If we're re-exporting a re-export it may actually re-export something in + // two namespaces, so the target may be listed twice. Make sure we only + // visit each node at most once. + for &item in cx.tcx.module_children(did).iter() { + if item.vis.is_public() { + let res = item.res.expect_non_local(); + if let Some(def_id) = res.mod_def_id() { + // If we're inlining a glob import, it's possible to have + // two distinct modules with the same name. We don't want to + // inline it, or mark any of its contents as visited. + if did == def_id + || inlined_names.contains(&(ItemType::Module, item.ident.name)) + || !visited.insert(def_id) + { + continue; + } + } + if let Res::PrimTy(p) = res { + // Primitive types can't be inlined so generate an import instead. + let prim_ty = clean::PrimitiveType::from(p); + items.push(clean::Item { + name: None, + attrs: Box::new(clean::Attributes::default()), + item_id: ItemId::Primitive(prim_ty, did.krate), + visibility: clean::Public, + kind: Box::new(clean::ImportItem(clean::Import::new_simple( + item.ident.name, + clean::ImportSource { + path: clean::Path { + res, + segments: vec![clean::PathSegment { + name: prim_ty.as_sym(), + args: clean::GenericArgs::AngleBracketed { + args: Default::default(), + bindings: ThinVec::new(), + }, + }], + }, + did: None, + }, + true, + ))), + cfg: None, + }); + } else if let Some(i) = try_inline(cx, did, None, res, item.ident.name, None, visited) { + items.extend(i) + } + } + } + + items +} + +pub(crate) fn print_inlined_const(tcx: TyCtxt<'_>, did: DefId) -> String { + if let Some(did) = did.as_local() { + let hir_id = tcx.hir().local_def_id_to_hir_id(did); + rustc_hir_pretty::id_to_string(&tcx.hir(), hir_id) + } else { + tcx.rendered_const(did).clone() + } +} + +fn build_const(cx: &mut DocContext<'_>, def_id: DefId) -> clean::Constant { + clean::Constant { + type_: clean_middle_ty(cx.tcx.type_of(def_id), cx, Some(def_id)), + kind: clean::ConstantKind::Extern { def_id }, + } +} + +fn build_static(cx: &mut DocContext<'_>, did: DefId, mutable: bool) -> clean::Static { + clean::Static { + type_: clean_middle_ty(cx.tcx.type_of(did), cx, Some(did)), + mutability: if mutable { Mutability::Mut } else { Mutability::Not }, + expr: None, + } +} + +fn build_macro( + cx: &mut DocContext<'_>, + def_id: DefId, + name: Symbol, + import_def_id: Option, +) -> clean::ItemKind { + match CStore::from_tcx(cx.tcx).load_macro_untracked(def_id, cx.sess()) { + LoadedMacro::MacroDef(item_def, _) => { + if let ast::ItemKind::MacroDef(ref def) = item_def.kind { + let vis = clean_visibility(cx.tcx.visibility(import_def_id.unwrap_or(def_id))); + clean::MacroItem(clean::Macro { + source: utils::display_macro_source(cx, name, def, def_id, vis), + }) + } else { + unreachable!() + } + } + LoadedMacro::ProcMacro(ext) => clean::ProcMacroItem(clean::ProcMacro { + kind: ext.macro_kind(), + helpers: ext.helper_attrs, + }), + } +} + +/// A trait's generics clause actually contains all of the predicates for all of +/// its associated types as well. We specifically move these clauses to the +/// associated types instead when displaying, so when we're generating the +/// generics for the trait itself we need to be sure to remove them. +/// We also need to remove the implied "recursive" Self: Trait bound. +/// +/// The inverse of this filtering logic can be found in the `Clean` +/// implementation for `AssociatedType` +fn filter_non_trait_generics(trait_did: DefId, mut g: clean::Generics) -> clean::Generics { + for pred in &mut g.where_predicates { + match *pred { + clean::WherePredicate::BoundPredicate { + ty: clean::Generic(ref s), + ref mut bounds, + .. + } if *s == kw::SelfUpper => { + bounds.retain(|bound| match bound { + clean::GenericBound::TraitBound(clean::PolyTrait { trait_, .. }, _) => { + trait_.def_id() != trait_did + } + _ => true, + }); + } + _ => {} + } + } + + g.where_predicates.retain(|pred| match pred { + clean::WherePredicate::BoundPredicate { + ty: clean::QPath { self_type: box clean::Generic(ref s), trait_, .. }, + bounds, + .. + } => !(bounds.is_empty() || *s == kw::SelfUpper && trait_.def_id() == trait_did), + _ => true, + }); + g +} + +/// Supertrait bounds for a trait are also listed in the generics coming from +/// the metadata for a crate, so we want to separate those out and create a new +/// list of explicit supertrait bounds to render nicely. +fn separate_supertrait_bounds( + mut g: clean::Generics, +) -> (clean::Generics, Vec) { + let mut ty_bounds = Vec::new(); + g.where_predicates.retain(|pred| match *pred { + clean::WherePredicate::BoundPredicate { ty: clean::Generic(ref s), ref bounds, .. } + if *s == kw::SelfUpper => + { + ty_bounds.extend(bounds.iter().cloned()); + false + } + _ => true, + }); + (g, ty_bounds) +} + +pub(crate) fn record_extern_trait(cx: &mut DocContext<'_>, did: DefId) { + if did.is_local() { + return; + } + + { + if cx.external_traits.borrow().contains_key(&did) || cx.active_extern_traits.contains(&did) + { + return; + } + } + + { + cx.active_extern_traits.insert(did); + } + + debug!("record_extern_trait: {:?}", did); + let trait_ = build_external_trait(cx, did); + + let trait_ = clean::TraitWithExtraInfo { + trait_, + is_notable: clean::utils::has_doc_flag(cx.tcx, did, sym::notable_trait), + }; + cx.external_traits.borrow_mut().insert(did, trait_); + cx.active_extern_traits.remove(&did); +} diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs new file mode 100644 index 000000000..929f5f89b --- /dev/null +++ b/src/librustdoc/clean/mod.rs @@ -0,0 +1,2242 @@ +//! This module contains the "cleaned" pieces of the AST, and the functions +//! that clean them. + +mod auto_trait; +mod blanket_impl; +pub(crate) mod cfg; +pub(crate) mod inline; +mod render_macro_matchers; +mod simplify; +pub(crate) mod types; +pub(crate) mod utils; + +use rustc_ast as ast; +use rustc_attr as attr; +use rustc_data_structures::fx::{FxHashMap, FxHashSet}; +use rustc_hir as hir; +use rustc_hir::def::{CtorKind, DefKind, Res}; +use rustc_hir::def_id::{DefId, LOCAL_CRATE}; +use rustc_hir::PredicateOrigin; +use rustc_infer::infer::region_constraints::{Constraint, RegionConstraintData}; +use rustc_middle::middle::resolve_lifetime as rl; +use rustc_middle::ty::fold::TypeFolder; +use rustc_middle::ty::subst::{InternalSubsts, Subst}; +use rustc_middle::ty::{self, AdtKind, DefIdTree, EarlyBinder, Lift, Ty, TyCtxt}; +use rustc_middle::{bug, span_bug}; +use rustc_span::hygiene::{AstPass, MacroKind}; +use rustc_span::symbol::{kw, sym, Ident, Symbol}; +use rustc_span::{self, ExpnKind}; +use rustc_typeck::hir_ty_to_ty; + +use std::assert_matches::assert_matches; +use std::collections::hash_map::Entry; +use std::collections::BTreeMap; +use std::default::Default; +use std::hash::Hash; +use std::{mem, vec}; + +use crate::core::{self, DocContext, ImplTraitParam}; +use crate::formats::item_type::ItemType; +use crate::visit_ast::Module as DocModule; + +use utils::*; + +pub(crate) use self::types::*; +pub(crate) use self::utils::{get_auto_trait_and_blanket_impls, krate, register_res}; + +pub(crate) trait Clean<'tcx, T> { + fn clean(&self, cx: &mut DocContext<'tcx>) -> T; +} + +impl<'tcx> Clean<'tcx, Item> for DocModule<'tcx> { + fn clean(&self, cx: &mut DocContext<'tcx>) -> Item { + let mut items: Vec = vec![]; + let mut inserted = FxHashSet::default(); + items.extend(self.foreigns.iter().map(|(item, renamed)| { + let item = clean_maybe_renamed_foreign_item(cx, item, *renamed); + if let Some(name) = item.name { + inserted.insert((item.type_(), name)); + } + item + })); + items.extend(self.mods.iter().map(|x| { + inserted.insert((ItemType::Module, x.name)); + x.clean(cx) + })); + + // Split up imports from all other items. + // + // This covers the case where somebody does an import which should pull in an item, + // but there's already an item with the same namespace and same name. Rust gives + // priority to the not-imported one, so we should, too. + items.extend(self.items.iter().flat_map(|(item, renamed)| { + // First, lower everything other than imports. + if matches!(item.kind, hir::ItemKind::Use(_, hir::UseKind::Glob)) { + return Vec::new(); + } + let v = clean_maybe_renamed_item(cx, item, *renamed); + for item in &v { + if let Some(name) = item.name { + inserted.insert((item.type_(), name)); + } + } + v + })); + items.extend(self.items.iter().flat_map(|(item, renamed)| { + // Now we actually lower the imports, skipping everything else. + if let hir::ItemKind::Use(path, hir::UseKind::Glob) = item.kind { + let name = renamed.unwrap_or_else(|| cx.tcx.hir().name(item.hir_id())); + clean_use_statement(item, name, path, hir::UseKind::Glob, cx, &mut inserted) + } else { + // skip everything else + Vec::new() + } + })); + + // determine if we should display the inner contents or + // the outer `mod` item for the source code. + + let span = Span::new({ + let where_outer = self.where_outer(cx.tcx); + let sm = cx.sess().source_map(); + let outer = sm.lookup_char_pos(where_outer.lo()); + let inner = sm.lookup_char_pos(self.where_inner.lo()); + if outer.file.start_pos == inner.file.start_pos { + // mod foo { ... } + where_outer + } else { + // mod foo; (and a separate SourceFile for the contents) + self.where_inner + } + }); + + Item::from_hir_id_and_parts( + self.id, + Some(self.name), + ModuleItem(Module { items, span }), + cx, + ) + } +} + +impl<'tcx> Clean<'tcx, Option> for hir::GenericBound<'tcx> { + fn clean(&self, cx: &mut DocContext<'tcx>) -> Option { + Some(match *self { + hir::GenericBound::Outlives(lt) => GenericBound::Outlives(clean_lifetime(lt, cx)), + hir::GenericBound::LangItemTrait(lang_item, span, _, generic_args) => { + let def_id = cx.tcx.require_lang_item(lang_item, Some(span)); + + let trait_ref = ty::TraitRef::identity(cx.tcx, def_id).skip_binder(); + + let generic_args = generic_args.clean(cx); + let GenericArgs::AngleBracketed { bindings, .. } = generic_args + else { + bug!("clean: parenthesized `GenericBound::LangItemTrait`"); + }; + + let trait_ = clean_trait_ref_with_bindings(cx, trait_ref, &bindings); + GenericBound::TraitBound( + PolyTrait { trait_, generic_params: vec![] }, + hir::TraitBoundModifier::None, + ) + } + hir::GenericBound::Trait(ref t, modifier) => { + // `T: ~const Destruct` is hidden because `T: Destruct` is a no-op. + if modifier == hir::TraitBoundModifier::MaybeConst + && cx.tcx.lang_items().destruct_trait() + == Some(t.trait_ref.trait_def_id().unwrap()) + { + return None; + } + + GenericBound::TraitBound(t.clean(cx), modifier) + } + }) + } +} + +pub(crate) fn clean_trait_ref_with_bindings<'tcx>( + cx: &mut DocContext<'tcx>, + trait_ref: ty::TraitRef<'tcx>, + bindings: &[TypeBinding], +) -> Path { + let kind = cx.tcx.def_kind(trait_ref.def_id).into(); + if !matches!(kind, ItemType::Trait | ItemType::TraitAlias) { + span_bug!(cx.tcx.def_span(trait_ref.def_id), "`TraitRef` had unexpected kind {:?}", kind); + } + inline::record_extern_fqn(cx, trait_ref.def_id, kind); + let path = external_path(cx, trait_ref.def_id, true, bindings.to_vec(), trait_ref.substs); + + debug!("ty::TraitRef\n subst: {:?}\n", trait_ref.substs); + + path +} + +fn clean_poly_trait_ref_with_bindings<'tcx>( + cx: &mut DocContext<'tcx>, + poly_trait_ref: ty::PolyTraitRef<'tcx>, + bindings: &[TypeBinding], +) -> GenericBound { + let poly_trait_ref = poly_trait_ref.lift_to_tcx(cx.tcx).unwrap(); + + // collect any late bound regions + let late_bound_regions: Vec<_> = cx + .tcx + .collect_referenced_late_bound_regions(&poly_trait_ref) + .into_iter() + .filter_map(|br| match br { + ty::BrNamed(_, name) if name != kw::UnderscoreLifetime => Some(GenericParamDef { + name, + kind: GenericParamDefKind::Lifetime { outlives: vec![] }, + }), + _ => None, + }) + .collect(); + + let trait_ = clean_trait_ref_with_bindings(cx, poly_trait_ref.skip_binder(), bindings); + GenericBound::TraitBound( + PolyTrait { trait_, generic_params: late_bound_regions }, + hir::TraitBoundModifier::None, + ) +} + +impl<'tcx> Clean<'tcx, GenericBound> for ty::PolyTraitRef<'tcx> { + fn clean(&self, cx: &mut DocContext<'tcx>) -> GenericBound { + clean_poly_trait_ref_with_bindings(cx, *self, &[]) + } +} + +fn clean_lifetime<'tcx>(lifetime: hir::Lifetime, cx: &mut DocContext<'tcx>) -> Lifetime { + let def = cx.tcx.named_region(lifetime.hir_id); + if let Some( + rl::Region::EarlyBound(_, node_id) + | rl::Region::LateBound(_, _, node_id) + | rl::Region::Free(_, node_id), + ) = def + { + if let Some(lt) = cx.substs.get(&node_id).and_then(|p| p.as_lt()).cloned() { + return lt; + } + } + Lifetime(lifetime.name.ident().name) +} + +pub(crate) fn clean_const<'tcx>(constant: &hir::ConstArg, cx: &mut DocContext<'tcx>) -> Constant { + let def_id = cx.tcx.hir().body_owner_def_id(constant.value.body).to_def_id(); + Constant { + type_: clean_middle_ty(cx.tcx.type_of(def_id), cx, Some(def_id)), + kind: ConstantKind::Anonymous { body: constant.value.body }, + } +} + +pub(crate) fn clean_middle_const<'tcx>( + constant: ty::Const<'tcx>, + cx: &mut DocContext<'tcx>, +) -> Constant { + // FIXME: instead of storing the stringified expression, store `self` directly instead. + Constant { + type_: clean_middle_ty(constant.ty(), cx, None), + kind: ConstantKind::TyConst { expr: constant.to_string() }, + } +} + +pub(crate) fn clean_middle_region<'tcx>(region: ty::Region<'tcx>) -> Option { + match *region { + ty::ReStatic => Some(Lifetime::statik()), + ty::ReLateBound(_, ty::BoundRegion { kind: ty::BrNamed(_, name), .. }) => { + if name != kw::UnderscoreLifetime { Some(Lifetime(name)) } else { None } + } + ty::ReEarlyBound(ref data) => { + if data.name != kw::UnderscoreLifetime { + Some(Lifetime(data.name)) + } else { + None + } + } + ty::ReLateBound(..) + | ty::ReFree(..) + | ty::ReVar(..) + | ty::RePlaceholder(..) + | ty::ReEmpty(_) + | ty::ReErased => { + debug!("cannot clean region {:?}", region); + None + } + } +} + +impl<'tcx> Clean<'tcx, Option> for hir::WherePredicate<'tcx> { + fn clean(&self, cx: &mut DocContext<'tcx>) -> Option { + if !self.in_where_clause() { + return None; + } + Some(match *self { + hir::WherePredicate::BoundPredicate(ref wbp) => { + let bound_params = wbp + .bound_generic_params + .iter() + .map(|param| { + // Higher-ranked params must be lifetimes. + // Higher-ranked lifetimes can't have bounds. + assert_matches!( + param, + hir::GenericParam { kind: hir::GenericParamKind::Lifetime { .. }, .. } + ); + Lifetime(param.name.ident().name) + }) + .collect(); + WherePredicate::BoundPredicate { + ty: clean_ty(wbp.bounded_ty, cx), + bounds: wbp.bounds.iter().filter_map(|x| x.clean(cx)).collect(), + bound_params, + } + } + + hir::WherePredicate::RegionPredicate(ref wrp) => WherePredicate::RegionPredicate { + lifetime: clean_lifetime(wrp.lifetime, cx), + bounds: wrp.bounds.iter().filter_map(|x| x.clean(cx)).collect(), + }, + + hir::WherePredicate::EqPredicate(ref wrp) => WherePredicate::EqPredicate { + lhs: clean_ty(wrp.lhs_ty, cx), + rhs: clean_ty(wrp.rhs_ty, cx).into(), + }, + }) + } +} + +impl<'tcx> Clean<'tcx, Option> for ty::Predicate<'tcx> { + fn clean(&self, cx: &mut DocContext<'tcx>) -> Option { + let bound_predicate = self.kind(); + match bound_predicate.skip_binder() { + ty::PredicateKind::Trait(pred) => { + clean_poly_trait_predicate(bound_predicate.rebind(pred), cx) + } + ty::PredicateKind::RegionOutlives(pred) => clean_region_outlives_predicate(pred), + ty::PredicateKind::TypeOutlives(pred) => clean_type_outlives_predicate(pred, cx), + ty::PredicateKind::Projection(pred) => Some(clean_projection_predicate(pred, cx)), + ty::PredicateKind::ConstEvaluatable(..) => None, + ty::PredicateKind::WellFormed(..) => None, + + ty::PredicateKind::Subtype(..) + | ty::PredicateKind::Coerce(..) + | ty::PredicateKind::ObjectSafe(..) + | ty::PredicateKind::ClosureKind(..) + | ty::PredicateKind::ConstEquate(..) + | ty::PredicateKind::TypeWellFormedFromEnv(..) => panic!("not user writable"), + } + } +} + +fn clean_poly_trait_predicate<'tcx>( + pred: ty::PolyTraitPredicate<'tcx>, + cx: &mut DocContext<'tcx>, +) -> Option { + // `T: ~const Destruct` is hidden because `T: Destruct` is a no-op. + if pred.skip_binder().constness == ty::BoundConstness::ConstIfConst + && Some(pred.skip_binder().def_id()) == cx.tcx.lang_items().destruct_trait() + { + return None; + } + + let poly_trait_ref = pred.map_bound(|pred| pred.trait_ref); + Some(WherePredicate::BoundPredicate { + ty: clean_middle_ty(poly_trait_ref.skip_binder().self_ty(), cx, None), + bounds: vec![poly_trait_ref.clean(cx)], + bound_params: Vec::new(), + }) +} + +fn clean_region_outlives_predicate<'tcx>( + pred: ty::OutlivesPredicate, ty::Region<'tcx>>, +) -> Option { + let ty::OutlivesPredicate(a, b) = pred; + + if a.is_empty() && b.is_empty() { + return None; + } + + Some(WherePredicate::RegionPredicate { + lifetime: clean_middle_region(a).expect("failed to clean lifetime"), + bounds: vec![GenericBound::Outlives( + clean_middle_region(b).expect("failed to clean bounds"), + )], + }) +} + +fn clean_type_outlives_predicate<'tcx>( + pred: ty::OutlivesPredicate, ty::Region<'tcx>>, + cx: &mut DocContext<'tcx>, +) -> Option { + let ty::OutlivesPredicate(ty, lt) = pred; + + if lt.is_empty() { + return None; + } + + Some(WherePredicate::BoundPredicate { + ty: clean_middle_ty(ty, cx, None), + bounds: vec![GenericBound::Outlives( + clean_middle_region(lt).expect("failed to clean lifetimes"), + )], + bound_params: Vec::new(), + }) +} + +fn clean_middle_term<'tcx>(term: ty::Term<'tcx>, cx: &mut DocContext<'tcx>) -> Term { + match term { + ty::Term::Ty(ty) => Term::Type(clean_middle_ty(ty, cx, None)), + ty::Term::Const(c) => Term::Constant(clean_middle_const(c, cx)), + } +} + +fn clean_hir_term<'tcx>(term: &hir::Term<'tcx>, cx: &mut DocContext<'tcx>) -> Term { + match term { + hir::Term::Ty(ty) => Term::Type(clean_ty(ty, cx)), + hir::Term::Const(c) => { + let def_id = cx.tcx.hir().local_def_id(c.hir_id); + Term::Constant(clean_middle_const(ty::Const::from_anon_const(cx.tcx, def_id), cx)) + } + } +} + +fn clean_projection_predicate<'tcx>( + pred: ty::ProjectionPredicate<'tcx>, + cx: &mut DocContext<'tcx>, +) -> WherePredicate { + let ty::ProjectionPredicate { projection_ty, term } = pred; + WherePredicate::EqPredicate { + lhs: clean_projection(projection_ty, cx, None), + rhs: clean_middle_term(term, cx), + } +} + +fn clean_projection<'tcx>( + ty: ty::ProjectionTy<'tcx>, + cx: &mut DocContext<'tcx>, + def_id: Option, +) -> Type { + let lifted = ty.lift_to_tcx(cx.tcx).unwrap(); + let trait_ = clean_trait_ref_with_bindings(cx, lifted.trait_ref(cx.tcx), &[]); + let self_type = clean_middle_ty(ty.self_ty(), cx, None); + let self_def_id = if let Some(def_id) = def_id { + cx.tcx.opt_parent(def_id).or(Some(def_id)) + } else { + self_type.def_id(&cx.cache) + }; + let should_show_cast = compute_should_show_cast(self_def_id, &trait_, &self_type); + Type::QPath { + assoc: Box::new(projection_to_path_segment(ty, cx)), + should_show_cast, + self_type: Box::new(self_type), + trait_, + } +} + +fn compute_should_show_cast(self_def_id: Option, trait_: &Path, self_type: &Type) -> bool { + !trait_.segments.is_empty() + && self_def_id + .zip(Some(trait_.def_id())) + .map_or(!self_type.is_self_type(), |(id, trait_)| id != trait_) +} + +fn projection_to_path_segment<'tcx>( + ty: ty::ProjectionTy<'tcx>, + cx: &mut DocContext<'tcx>, +) -> PathSegment { + let item = cx.tcx.associated_item(ty.item_def_id); + let generics = cx.tcx.generics_of(ty.item_def_id); + PathSegment { + name: item.name, + args: GenericArgs::AngleBracketed { + args: substs_to_args(cx, &ty.substs[generics.parent_count..], false).into(), + bindings: Default::default(), + }, + } +} + +fn clean_generic_param_def<'tcx>( + def: &ty::GenericParamDef, + cx: &mut DocContext<'tcx>, +) -> GenericParamDef { + let (name, kind) = match def.kind { + ty::GenericParamDefKind::Lifetime => { + (def.name, GenericParamDefKind::Lifetime { outlives: vec![] }) + } + ty::GenericParamDefKind::Type { has_default, synthetic, .. } => { + let default = if has_default { + Some(clean_middle_ty(cx.tcx.type_of(def.def_id), cx, Some(def.def_id))) + } else { + None + }; + ( + def.name, + GenericParamDefKind::Type { + did: def.def_id, + bounds: vec![], // These are filled in from the where-clauses. + default: default.map(Box::new), + synthetic, + }, + ) + } + ty::GenericParamDefKind::Const { has_default } => ( + def.name, + GenericParamDefKind::Const { + did: def.def_id, + ty: Box::new(clean_middle_ty(cx.tcx.type_of(def.def_id), cx, Some(def.def_id))), + default: match has_default { + true => Some(Box::new(cx.tcx.const_param_default(def.def_id).to_string())), + false => None, + }, + }, + ), + }; + + GenericParamDef { name, kind } +} + +fn clean_generic_param<'tcx>( + cx: &mut DocContext<'tcx>, + generics: Option<&hir::Generics<'tcx>>, + param: &hir::GenericParam<'tcx>, +) -> GenericParamDef { + let did = cx.tcx.hir().local_def_id(param.hir_id); + let (name, kind) = match param.kind { + hir::GenericParamKind::Lifetime { .. } => { + let outlives = if let Some(generics) = generics { + generics + .outlives_for_param(did) + .filter(|bp| !bp.in_where_clause) + .flat_map(|bp| bp.bounds) + .map(|bound| match bound { + hir::GenericBound::Outlives(lt) => clean_lifetime(*lt, cx), + _ => panic!(), + }) + .collect() + } else { + Vec::new() + }; + (param.name.ident().name, GenericParamDefKind::Lifetime { outlives }) + } + hir::GenericParamKind::Type { ref default, synthetic } => { + let bounds = if let Some(generics) = generics { + generics + .bounds_for_param(did) + .filter(|bp| bp.origin != PredicateOrigin::WhereClause) + .flat_map(|bp| bp.bounds) + .filter_map(|x| x.clean(cx)) + .collect() + } else { + Vec::new() + }; + ( + param.name.ident().name, + GenericParamDefKind::Type { + did: did.to_def_id(), + bounds, + default: default.map(|t| clean_ty(t, cx)).map(Box::new), + synthetic, + }, + ) + } + hir::GenericParamKind::Const { ty, default } => ( + param.name.ident().name, + GenericParamDefKind::Const { + did: did.to_def_id(), + ty: Box::new(clean_ty(ty, cx)), + default: default.map(|ct| { + let def_id = cx.tcx.hir().local_def_id(ct.hir_id); + Box::new(ty::Const::from_anon_const(cx.tcx, def_id).to_string()) + }), + }, + ), + }; + + GenericParamDef { name, kind } +} + +/// Synthetic type-parameters are inserted after normal ones. +/// In order for normal parameters to be able to refer to synthetic ones, +/// scans them first. +fn is_impl_trait(param: &hir::GenericParam<'_>) -> bool { + match param.kind { + hir::GenericParamKind::Type { synthetic, .. } => synthetic, + _ => false, + } +} + +/// This can happen for `async fn`, e.g. `async fn f<'_>(&'_ self)`. +/// +/// See `lifetime_to_generic_param` in `rustc_ast_lowering` for more information. +fn is_elided_lifetime(param: &hir::GenericParam<'_>) -> bool { + matches!(param.kind, hir::GenericParamKind::Lifetime { kind: hir::LifetimeParamKind::Elided }) +} + +impl<'tcx> Clean<'tcx, Generics> for hir::Generics<'tcx> { + fn clean(&self, cx: &mut DocContext<'tcx>) -> Generics { + let impl_trait_params = self + .params + .iter() + .filter(|param| is_impl_trait(param)) + .map(|param| { + let param = clean_generic_param(cx, Some(self), param); + match param.kind { + GenericParamDefKind::Lifetime { .. } => unreachable!(), + GenericParamDefKind::Type { did, ref bounds, .. } => { + cx.impl_trait_bounds.insert(did.into(), bounds.clone()); + } + GenericParamDefKind::Const { .. } => unreachable!(), + } + param + }) + .collect::>(); + + let mut params = Vec::with_capacity(self.params.len()); + for p in self.params.iter().filter(|p| !is_impl_trait(p) && !is_elided_lifetime(p)) { + let p = clean_generic_param(cx, Some(self), p); + params.push(p); + } + params.extend(impl_trait_params); + + let mut generics = Generics { + params, + where_predicates: self.predicates.iter().filter_map(|x| x.clean(cx)).collect(), + }; + + // Some duplicates are generated for ?Sized bounds between type params and where + // predicates. The point in here is to move the bounds definitions from type params + // to where predicates when such cases occur. + for where_pred in &mut generics.where_predicates { + match *where_pred { + WherePredicate::BoundPredicate { + ty: Generic(ref name), ref mut bounds, .. + } => { + if bounds.is_empty() { + for param in &mut generics.params { + match param.kind { + GenericParamDefKind::Lifetime { .. } => {} + GenericParamDefKind::Type { bounds: ref mut ty_bounds, .. } => { + if ¶m.name == name { + mem::swap(bounds, ty_bounds); + break; + } + } + GenericParamDefKind::Const { .. } => {} + } + } + } + } + _ => continue, + } + } + generics + } +} + +fn clean_ty_generics<'tcx>( + cx: &mut DocContext<'tcx>, + gens: &ty::Generics, + preds: ty::GenericPredicates<'tcx>, +) -> Generics { + // Don't populate `cx.impl_trait_bounds` before `clean`ning `where` clauses, + // since `Clean for ty::Predicate` would consume them. + let mut impl_trait = BTreeMap::>::default(); + + // Bounds in the type_params and lifetimes fields are repeated in the + // predicates field (see rustc_typeck::collect::ty_generics), so remove + // them. + let stripped_params = gens + .params + .iter() + .filter_map(|param| match param.kind { + ty::GenericParamDefKind::Lifetime if param.name == kw::UnderscoreLifetime => None, + ty::GenericParamDefKind::Lifetime => Some(clean_generic_param_def(param, cx)), + ty::GenericParamDefKind::Type { synthetic, .. } => { + if param.name == kw::SelfUpper { + assert_eq!(param.index, 0); + return None; + } + if synthetic { + impl_trait.insert(param.index.into(), vec![]); + return None; + } + Some(clean_generic_param_def(param, cx)) + } + ty::GenericParamDefKind::Const { .. } => Some(clean_generic_param_def(param, cx)), + }) + .collect::>(); + + // param index -> [(DefId of trait, associated type name and generics, type)] + let mut impl_trait_proj = FxHashMap::)>>::default(); + + let where_predicates = preds + .predicates + .iter() + .flat_map(|(p, _)| { + let mut projection = None; + let param_idx = (|| { + let bound_p = p.kind(); + match bound_p.skip_binder() { + ty::PredicateKind::Trait(pred) => { + if let ty::Param(param) = pred.self_ty().kind() { + return Some(param.index); + } + } + ty::PredicateKind::TypeOutlives(ty::OutlivesPredicate(ty, _reg)) => { + if let ty::Param(param) = ty.kind() { + return Some(param.index); + } + } + ty::PredicateKind::Projection(p) => { + if let ty::Param(param) = p.projection_ty.self_ty().kind() { + projection = Some(bound_p.rebind(p)); + return Some(param.index); + } + } + _ => (), + } + + None + })(); + + if let Some(param_idx) = param_idx { + if let Some(b) = impl_trait.get_mut(¶m_idx.into()) { + let p: WherePredicate = p.clean(cx)?; + + b.extend( + p.get_bounds() + .into_iter() + .flatten() + .cloned() + .filter(|b| !b.is_sized_bound(cx)), + ); + + let proj = projection.map(|p| { + ( + clean_projection(p.skip_binder().projection_ty, cx, None), + p.skip_binder().term, + ) + }); + if let Some(((_, trait_did, name), rhs)) = proj + .as_ref() + .and_then(|(lhs, rhs): &(Type, _)| Some((lhs.projection()?, rhs))) + { + // FIXME(...): Remove this unwrap() + impl_trait_proj.entry(param_idx).or_default().push(( + trait_did, + name, + rhs.ty().unwrap(), + )); + } + + return None; + } + } + + Some(p) + }) + .collect::>(); + + for (param, mut bounds) in impl_trait { + // Move trait bounds to the front. + bounds.sort_by_key(|b| !matches!(b, GenericBound::TraitBound(..))); + + if let crate::core::ImplTraitParam::ParamIndex(idx) = param { + if let Some(proj) = impl_trait_proj.remove(&idx) { + for (trait_did, name, rhs) in proj { + let rhs = clean_middle_ty(rhs, cx, None); + simplify::merge_bounds(cx, &mut bounds, trait_did, name, &Term::Type(rhs)); + } + } + } else { + unreachable!(); + } + + cx.impl_trait_bounds.insert(param, bounds); + } + + // Now that `cx.impl_trait_bounds` is populated, we can process + // remaining predicates which could contain `impl Trait`. + let mut where_predicates = + where_predicates.into_iter().flat_map(|p| p.clean(cx)).collect::>(); + + // Type parameters have a Sized bound by default unless removed with + // ?Sized. Scan through the predicates and mark any type parameter with + // a Sized bound, removing the bounds as we find them. + // + // Note that associated types also have a sized bound by default, but we + // don't actually know the set of associated types right here so that's + // handled in cleaning associated types + let mut sized_params = FxHashSet::default(); + where_predicates.retain(|pred| match *pred { + WherePredicate::BoundPredicate { ty: Generic(ref g), ref bounds, .. } => { + if bounds.iter().any(|b| b.is_sized_bound(cx)) { + sized_params.insert(*g); + false + } else { + true + } + } + _ => true, + }); + + // Run through the type parameters again and insert a ?Sized + // unbound for any we didn't find to be Sized. + for tp in &stripped_params { + if matches!(tp.kind, types::GenericParamDefKind::Type { .. }) + && !sized_params.contains(&tp.name) + { + where_predicates.push(WherePredicate::BoundPredicate { + ty: Type::Generic(tp.name), + bounds: vec![GenericBound::maybe_sized(cx)], + bound_params: Vec::new(), + }) + } + } + + // It would be nice to collect all of the bounds on a type and recombine + // them if possible, to avoid e.g., `where T: Foo, T: Bar, T: Sized, T: 'a` + // and instead see `where T: Foo + Bar + Sized + 'a` + + Generics { + params: stripped_params, + where_predicates: simplify::where_clauses(cx, where_predicates), + } +} + +fn clean_fn_or_proc_macro<'tcx>( + item: &hir::Item<'tcx>, + sig: &hir::FnSig<'tcx>, + generics: &hir::Generics<'tcx>, + body_id: hir::BodyId, + name: &mut Symbol, + cx: &mut DocContext<'tcx>, +) -> ItemKind { + let attrs = cx.tcx.hir().attrs(item.hir_id()); + let macro_kind = attrs.iter().find_map(|a| { + if a.has_name(sym::proc_macro) { + Some(MacroKind::Bang) + } else if a.has_name(sym::proc_macro_derive) { + Some(MacroKind::Derive) + } else if a.has_name(sym::proc_macro_attribute) { + Some(MacroKind::Attr) + } else { + None + } + }); + match macro_kind { + Some(kind) => { + if kind == MacroKind::Derive { + *name = attrs + .lists(sym::proc_macro_derive) + .find_map(|mi| mi.ident()) + .expect("proc-macro derives require a name") + .name; + } + + let mut helpers = Vec::new(); + for mi in attrs.lists(sym::proc_macro_derive) { + if !mi.has_name(sym::attributes) { + continue; + } + + if let Some(list) = mi.meta_item_list() { + for inner_mi in list { + if let Some(ident) = inner_mi.ident() { + helpers.push(ident.name); + } + } + } + } + ProcMacroItem(ProcMacro { kind, helpers }) + } + None => { + let mut func = clean_function(cx, sig, generics, body_id); + clean_fn_decl_legacy_const_generics(&mut func, attrs); + FunctionItem(func) + } + } +} + +/// This is needed to make it more "readable" when documenting functions using +/// `rustc_legacy_const_generics`. More information in +/// . +fn clean_fn_decl_legacy_const_generics(func: &mut Function, attrs: &[ast::Attribute]) { + for meta_item_list in attrs + .iter() + .filter(|a| a.has_name(sym::rustc_legacy_const_generics)) + .filter_map(|a| a.meta_item_list()) + { + for (pos, literal) in meta_item_list.iter().filter_map(|meta| meta.literal()).enumerate() { + match literal.kind { + ast::LitKind::Int(a, _) => { + let gen = func.generics.params.remove(0); + if let GenericParamDef { name, kind: GenericParamDefKind::Const { ty, .. } } = + gen + { + func.decl + .inputs + .values + .insert(a as _, Argument { name, type_: *ty, is_const: true }); + } else { + panic!("unexpected non const in position {pos}"); + } + } + _ => panic!("invalid arg index"), + } + } + } +} + +fn clean_function<'tcx>( + cx: &mut DocContext<'tcx>, + sig: &hir::FnSig<'tcx>, + generics: &hir::Generics<'tcx>, + body_id: hir::BodyId, +) -> Box { + let (generics, decl) = enter_impl_trait(cx, |cx| { + // NOTE: generics must be cleaned before args + let generics = generics.clean(cx); + let args = clean_args_from_types_and_body_id(cx, sig.decl.inputs, body_id); + let decl = clean_fn_decl_with_args(cx, sig.decl, args); + (generics, decl) + }); + Box::new(Function { decl, generics }) +} + +fn clean_args_from_types_and_names<'tcx>( + cx: &mut DocContext<'tcx>, + types: &[hir::Ty<'tcx>], + names: &[Ident], +) -> Arguments { + Arguments { + values: types + .iter() + .enumerate() + .map(|(i, ty)| { + let mut name = names.get(i).map_or(kw::Empty, |ident| ident.name); + if name.is_empty() { + name = kw::Underscore; + } + Argument { name, type_: clean_ty(ty, cx), is_const: false } + }) + .collect(), + } +} + +fn clean_args_from_types_and_body_id<'tcx>( + cx: &mut DocContext<'tcx>, + types: &[hir::Ty<'tcx>], + body_id: hir::BodyId, +) -> Arguments { + let body = cx.tcx.hir().body(body_id); + + Arguments { + values: types + .iter() + .enumerate() + .map(|(i, ty)| Argument { + name: name_from_pat(body.params[i].pat), + type_: clean_ty(ty, cx), + is_const: false, + }) + .collect(), + } +} + +fn clean_fn_decl_with_args<'tcx>( + cx: &mut DocContext<'tcx>, + decl: &hir::FnDecl<'tcx>, + args: Arguments, +) -> FnDecl { + let output = match decl.output { + hir::FnRetTy::Return(typ) => Return(clean_ty(typ, cx)), + hir::FnRetTy::DefaultReturn(..) => DefaultReturn, + }; + FnDecl { inputs: args, output, c_variadic: decl.c_variadic } +} + +fn clean_fn_decl_from_did_and_sig<'tcx>( + cx: &mut DocContext<'tcx>, + did: Option, + sig: ty::PolyFnSig<'tcx>, +) -> FnDecl { + let mut names = did.map_or(&[] as &[_], |did| cx.tcx.fn_arg_names(did)).iter(); + + // We assume all empty tuples are default return type. This theoretically can discard `-> ()`, + // but shouldn't change any code meaning. + let output = match clean_middle_ty(sig.skip_binder().output(), cx, None) { + Type::Tuple(inner) if inner.is_empty() => DefaultReturn, + ty => Return(ty), + }; + + FnDecl { + output, + c_variadic: sig.skip_binder().c_variadic, + inputs: Arguments { + values: sig + .skip_binder() + .inputs() + .iter() + .map(|t| Argument { + type_: clean_middle_ty(*t, cx, None), + name: names.next().map_or(kw::Empty, |i| i.name), + is_const: false, + }) + .collect(), + }, + } +} + +fn clean_trait_ref<'tcx>(trait_ref: &hir::TraitRef<'tcx>, cx: &mut DocContext<'tcx>) -> Path { + let path = clean_path(trait_ref.path, cx); + register_res(cx, path.res); + path +} + +impl<'tcx> Clean<'tcx, PolyTrait> for hir::PolyTraitRef<'tcx> { + fn clean(&self, cx: &mut DocContext<'tcx>) -> PolyTrait { + PolyTrait { + trait_: clean_trait_ref(&self.trait_ref, cx), + generic_params: self + .bound_generic_params + .iter() + .filter(|p| !is_elided_lifetime(p)) + .map(|x| clean_generic_param(cx, None, x)) + .collect(), + } + } +} + +impl<'tcx> Clean<'tcx, Item> for hir::TraitItem<'tcx> { + fn clean(&self, cx: &mut DocContext<'tcx>) -> Item { + let local_did = self.def_id.to_def_id(); + cx.with_param_env(local_did, |cx| { + let inner = match self.kind { + hir::TraitItemKind::Const(ty, Some(default)) => AssocConstItem( + clean_ty(ty, cx), + ConstantKind::Local { def_id: local_did, body: default }, + ), + hir::TraitItemKind::Const(ty, None) => TyAssocConstItem(clean_ty(ty, cx)), + hir::TraitItemKind::Fn(ref sig, hir::TraitFn::Provided(body)) => { + let m = clean_function(cx, sig, self.generics, body); + MethodItem(m, None) + } + hir::TraitItemKind::Fn(ref sig, hir::TraitFn::Required(names)) => { + let (generics, decl) = enter_impl_trait(cx, |cx| { + // NOTE: generics must be cleaned before args + let generics = self.generics.clean(cx); + let args = clean_args_from_types_and_names(cx, sig.decl.inputs, names); + let decl = clean_fn_decl_with_args(cx, sig.decl, args); + (generics, decl) + }); + TyMethodItem(Box::new(Function { decl, generics })) + } + hir::TraitItemKind::Type(bounds, Some(default)) => { + let generics = enter_impl_trait(cx, |cx| self.generics.clean(cx)); + let bounds = bounds.iter().filter_map(|x| x.clean(cx)).collect(); + let item_type = clean_middle_ty(hir_ty_to_ty(cx.tcx, default), cx, None); + AssocTypeItem( + Box::new(Typedef { + type_: clean_ty(default, cx), + generics, + item_type: Some(item_type), + }), + bounds, + ) + } + hir::TraitItemKind::Type(bounds, None) => { + let generics = enter_impl_trait(cx, |cx| self.generics.clean(cx)); + let bounds = bounds.iter().filter_map(|x| x.clean(cx)).collect(); + TyAssocTypeItem(Box::new(generics), bounds) + } + }; + let what_rustc_thinks = + Item::from_def_id_and_parts(local_did, Some(self.ident.name), inner, cx); + // Trait items always inherit the trait's visibility -- we don't want to show `pub`. + Item { visibility: Inherited, ..what_rustc_thinks } + }) + } +} + +impl<'tcx> Clean<'tcx, Item> for hir::ImplItem<'tcx> { + fn clean(&self, cx: &mut DocContext<'tcx>) -> Item { + let local_did = self.def_id.to_def_id(); + cx.with_param_env(local_did, |cx| { + let inner = match self.kind { + hir::ImplItemKind::Const(ty, expr) => { + let default = ConstantKind::Local { def_id: local_did, body: expr }; + AssocConstItem(clean_ty(ty, cx), default) + } + hir::ImplItemKind::Fn(ref sig, body) => { + let m = clean_function(cx, sig, self.generics, body); + let defaultness = cx.tcx.impl_defaultness(self.def_id); + MethodItem(m, Some(defaultness)) + } + hir::ImplItemKind::TyAlias(hir_ty) => { + let type_ = clean_ty(hir_ty, cx); + let generics = self.generics.clean(cx); + let item_type = clean_middle_ty(hir_ty_to_ty(cx.tcx, hir_ty), cx, None); + AssocTypeItem( + Box::new(Typedef { type_, generics, item_type: Some(item_type) }), + Vec::new(), + ) + } + }; + + let mut what_rustc_thinks = + Item::from_def_id_and_parts(local_did, Some(self.ident.name), inner, cx); + + let impl_ref = cx.tcx.impl_trait_ref(cx.tcx.local_parent(self.def_id)); + + // Trait impl items always inherit the impl's visibility -- + // we don't want to show `pub`. + if impl_ref.is_some() { + what_rustc_thinks.visibility = Inherited; + } + + what_rustc_thinks + }) + } +} + +impl<'tcx> Clean<'tcx, Item> for ty::AssocItem { + fn clean(&self, cx: &mut DocContext<'tcx>) -> Item { + let tcx = cx.tcx; + let kind = match self.kind { + ty::AssocKind::Const => { + let ty = clean_middle_ty(tcx.type_of(self.def_id), cx, Some(self.def_id)); + + let provided = match self.container { + ty::ImplContainer => true, + ty::TraitContainer => tcx.impl_defaultness(self.def_id).has_value(), + }; + if provided { + AssocConstItem(ty, ConstantKind::Extern { def_id: self.def_id }) + } else { + TyAssocConstItem(ty) + } + } + ty::AssocKind::Fn => { + let generics = clean_ty_generics( + cx, + tcx.generics_of(self.def_id), + tcx.explicit_predicates_of(self.def_id), + ); + let sig = tcx.fn_sig(self.def_id); + let mut decl = clean_fn_decl_from_did_and_sig(cx, Some(self.def_id), sig); + + if self.fn_has_self_parameter { + let self_ty = match self.container { + ty::ImplContainer => tcx.type_of(self.container_id(tcx)), + ty::TraitContainer => tcx.types.self_param, + }; + let self_arg_ty = sig.input(0).skip_binder(); + if self_arg_ty == self_ty { + decl.inputs.values[0].type_ = Generic(kw::SelfUpper); + } else if let ty::Ref(_, ty, _) = *self_arg_ty.kind() { + if ty == self_ty { + match decl.inputs.values[0].type_ { + BorrowedRef { ref mut type_, .. } => { + **type_ = Generic(kw::SelfUpper) + } + _ => unreachable!(), + } + } + } + } + + let provided = match self.container { + ty::ImplContainer => true, + ty::TraitContainer => self.defaultness(tcx).has_value(), + }; + if provided { + let defaultness = match self.container { + ty::ImplContainer => Some(self.defaultness(tcx)), + ty::TraitContainer => None, + }; + MethodItem(Box::new(Function { generics, decl }), defaultness) + } else { + TyMethodItem(Box::new(Function { generics, decl })) + } + } + ty::AssocKind::Type => { + let my_name = self.name; + + fn param_eq_arg(param: &GenericParamDef, arg: &GenericArg) -> bool { + match (¶m.kind, arg) { + (GenericParamDefKind::Type { .. }, GenericArg::Type(Type::Generic(ty))) + if *ty == param.name => + { + true + } + ( + GenericParamDefKind::Lifetime { .. }, + GenericArg::Lifetime(Lifetime(lt)), + ) if *lt == param.name => true, + (GenericParamDefKind::Const { .. }, GenericArg::Const(c)) => { + match &c.kind { + ConstantKind::TyConst { expr } => expr == param.name.as_str(), + _ => false, + } + } + _ => false, + } + } + + if let ty::TraitContainer = self.container { + let bounds = tcx.explicit_item_bounds(self.def_id); + let predicates = ty::GenericPredicates { parent: None, predicates: bounds }; + let mut generics = + clean_ty_generics(cx, tcx.generics_of(self.def_id), predicates); + // Filter out the bounds that are (likely?) directly attached to the associated type, + // as opposed to being located in the where clause. + let mut bounds = generics + .where_predicates + .drain_filter(|pred| match *pred { + WherePredicate::BoundPredicate { + ty: QPath { ref assoc, ref self_type, ref trait_, .. }, + .. + } => { + if assoc.name != my_name { + return false; + } + if trait_.def_id() != self.container_id(tcx) { + return false; + } + match **self_type { + Generic(ref s) if *s == kw::SelfUpper => {} + _ => return false, + } + match &assoc.args { + GenericArgs::AngleBracketed { args, bindings } => { + if !bindings.is_empty() + || generics + .params + .iter() + .zip(args.iter()) + .any(|(param, arg)| !param_eq_arg(param, arg)) + { + return false; + } + } + GenericArgs::Parenthesized { .. } => { + // The only time this happens is if we're inside the rustdoc for Fn(), + // which only has one associated type, which is not a GAT, so whatever. + } + } + true + } + _ => false, + }) + .flat_map(|pred| { + if let WherePredicate::BoundPredicate { bounds, .. } = pred { + bounds + } else { + unreachable!() + } + }) + .collect::>(); + // Our Sized/?Sized bound didn't get handled when creating the generics + // because we didn't actually get our whole set of bounds until just now + // (some of them may have come from the trait). If we do have a sized + // bound, we remove it, and if we don't then we add the `?Sized` bound + // at the end. + match bounds.iter().position(|b| b.is_sized_bound(cx)) { + Some(i) => { + bounds.remove(i); + } + None => bounds.push(GenericBound::maybe_sized(cx)), + } + + if tcx.impl_defaultness(self.def_id).has_value() { + AssocTypeItem( + Box::new(Typedef { + type_: clean_middle_ty( + tcx.type_of(self.def_id), + cx, + Some(self.def_id), + ), + generics, + // FIXME: should we obtain the Type from HIR and pass it on here? + item_type: None, + }), + bounds, + ) + } else { + TyAssocTypeItem(Box::new(generics), bounds) + } + } else { + // FIXME: when could this happen? Associated items in inherent impls? + AssocTypeItem( + Box::new(Typedef { + type_: clean_middle_ty(tcx.type_of(self.def_id), cx, Some(self.def_id)), + generics: Generics { params: Vec::new(), where_predicates: Vec::new() }, + item_type: None, + }), + Vec::new(), + ) + } + } + }; + + let mut what_rustc_thinks = + Item::from_def_id_and_parts(self.def_id, Some(self.name), kind, cx); + + let impl_ref = tcx.impl_trait_ref(tcx.parent(self.def_id)); + + // Trait impl items always inherit the impl's visibility -- + // we don't want to show `pub`. + if impl_ref.is_some() { + what_rustc_thinks.visibility = Visibility::Inherited; + } + + what_rustc_thinks + } +} + +fn clean_qpath<'tcx>(hir_ty: &hir::Ty<'tcx>, cx: &mut DocContext<'tcx>) -> Type { + let hir::Ty { hir_id: _, span, ref kind } = *hir_ty; + let hir::TyKind::Path(qpath) = kind else { unreachable!() }; + + match qpath { + hir::QPath::Resolved(None, path) => { + if let Res::Def(DefKind::TyParam, did) = path.res { + if let Some(new_ty) = cx.substs.get(&did).and_then(|p| p.as_ty()).cloned() { + return new_ty; + } + if let Some(bounds) = cx.impl_trait_bounds.remove(&did.into()) { + return ImplTrait(bounds); + } + } + + if let Some(expanded) = maybe_expand_private_type_alias(cx, path) { + expanded + } else { + let path = clean_path(path, cx); + resolve_type(cx, path) + } + } + hir::QPath::Resolved(Some(qself), p) => { + // Try to normalize `::T` to a type + let ty = hir_ty_to_ty(cx.tcx, hir_ty); + if let Some(normalized_value) = normalize(cx, ty) { + return clean_middle_ty(normalized_value, cx, None); + } + + let trait_segments = &p.segments[..p.segments.len() - 1]; + let trait_def = cx.tcx.associated_item(p.res.def_id()).container_id(cx.tcx); + let trait_ = self::Path { + res: Res::Def(DefKind::Trait, trait_def), + segments: trait_segments.iter().map(|x| x.clean(cx)).collect(), + }; + register_res(cx, trait_.res); + let self_def_id = DefId::local(qself.hir_id.owner.local_def_index); + let self_type = clean_ty(qself, cx); + let should_show_cast = compute_should_show_cast(Some(self_def_id), &trait_, &self_type); + Type::QPath { + assoc: Box::new(p.segments.last().expect("segments were empty").clean(cx)), + should_show_cast, + self_type: Box::new(self_type), + trait_, + } + } + hir::QPath::TypeRelative(qself, segment) => { + let ty = hir_ty_to_ty(cx.tcx, hir_ty); + let res = match ty.kind() { + ty::Projection(proj) => Res::Def(DefKind::Trait, proj.trait_ref(cx.tcx).def_id), + // Rustdoc handles `ty::Error`s by turning them into `Type::Infer`s. + ty::Error(_) => return Type::Infer, + _ => bug!("clean: expected associated type, found `{:?}`", ty), + }; + let trait_ = clean_path(&hir::Path { span, res, segments: &[] }, cx); + register_res(cx, trait_.res); + let self_def_id = res.opt_def_id(); + let self_type = clean_ty(qself, cx); + let should_show_cast = compute_should_show_cast(self_def_id, &trait_, &self_type); + Type::QPath { + assoc: Box::new(segment.clean(cx)), + should_show_cast, + self_type: Box::new(self_type), + trait_, + } + } + hir::QPath::LangItem(..) => bug!("clean: requiring documentation of lang item"), + } +} + +fn maybe_expand_private_type_alias<'tcx>( + cx: &mut DocContext<'tcx>, + path: &hir::Path<'tcx>, +) -> Option { + let Res::Def(DefKind::TyAlias, def_id) = path.res else { return None }; + // Substitute private type aliases + let def_id = def_id.as_local()?; + let alias = if !cx.cache.access_levels.is_exported(def_id.to_def_id()) { + &cx.tcx.hir().expect_item(def_id).kind + } else { + return None; + }; + let hir::ItemKind::TyAlias(ty, generics) = alias else { return None }; + + let provided_params = &path.segments.last().expect("segments were empty"); + let mut substs = FxHashMap::default(); + let generic_args = provided_params.args(); + + let mut indices: hir::GenericParamCount = Default::default(); + for param in generics.params.iter() { + match param.kind { + hir::GenericParamKind::Lifetime { .. } => { + let mut j = 0; + let lifetime = generic_args.args.iter().find_map(|arg| match arg { + hir::GenericArg::Lifetime(lt) => { + if indices.lifetimes == j { + return Some(lt); + } + j += 1; + None + } + _ => None, + }); + if let Some(lt) = lifetime.cloned() { + let lt_def_id = cx.tcx.hir().local_def_id(param.hir_id); + let cleaned = + if !lt.is_elided() { clean_lifetime(lt, cx) } else { Lifetime::elided() }; + substs.insert(lt_def_id.to_def_id(), SubstParam::Lifetime(cleaned)); + } + indices.lifetimes += 1; + } + hir::GenericParamKind::Type { ref default, .. } => { + let ty_param_def_id = cx.tcx.hir().local_def_id(param.hir_id); + let mut j = 0; + let type_ = generic_args.args.iter().find_map(|arg| match arg { + hir::GenericArg::Type(ty) => { + if indices.types == j { + return Some(ty); + } + j += 1; + None + } + _ => None, + }); + if let Some(ty) = type_ { + substs.insert(ty_param_def_id.to_def_id(), SubstParam::Type(clean_ty(ty, cx))); + } else if let Some(default) = *default { + substs.insert( + ty_param_def_id.to_def_id(), + SubstParam::Type(clean_ty(default, cx)), + ); + } + indices.types += 1; + } + hir::GenericParamKind::Const { .. } => { + let const_param_def_id = cx.tcx.hir().local_def_id(param.hir_id); + let mut j = 0; + let const_ = generic_args.args.iter().find_map(|arg| match arg { + hir::GenericArg::Const(ct) => { + if indices.consts == j { + return Some(ct); + } + j += 1; + None + } + _ => None, + }); + if let Some(ct) = const_ { + substs.insert( + const_param_def_id.to_def_id(), + SubstParam::Constant(clean_const(ct, cx)), + ); + } + // FIXME(const_generics_defaults) + indices.consts += 1; + } + } + } + + Some(cx.enter_alias(substs, |cx| clean_ty(ty, cx))) +} + +pub(crate) fn clean_ty<'tcx>(ty: &hir::Ty<'tcx>, cx: &mut DocContext<'tcx>) -> Type { + use rustc_hir::*; + + match ty.kind { + TyKind::Never => Primitive(PrimitiveType::Never), + TyKind::Ptr(ref m) => RawPointer(m.mutbl, Box::new(clean_ty(m.ty, cx))), + TyKind::Rptr(ref l, ref m) => { + // There are two times a `Fresh` lifetime can be created: + // 1. For `&'_ x`, written by the user. This corresponds to `lower_lifetime` in `rustc_ast_lowering`. + // 2. For `&x` as a parameter to an `async fn`. This corresponds to `elided_ref_lifetime in `rustc_ast_lowering`. + // See #59286 for more information. + // Ideally we would only hide the `'_` for case 2., but I don't know a way to distinguish it. + // Turning `fn f(&'_ self)` into `fn f(&self)` isn't the worst thing in the world, though; + // there's no case where it could cause the function to fail to compile. + let elided = + l.is_elided() || matches!(l.name, LifetimeName::Param(_, ParamName::Fresh)); + let lifetime = if elided { None } else { Some(clean_lifetime(*l, cx)) }; + BorrowedRef { lifetime, mutability: m.mutbl, type_: Box::new(clean_ty(m.ty, cx)) } + } + TyKind::Slice(ty) => Slice(Box::new(clean_ty(ty, cx))), + TyKind::Array(ty, ref length) => { + let length = match length { + hir::ArrayLen::Infer(_, _) => "_".to_string(), + hir::ArrayLen::Body(anon_const) => { + let def_id = cx.tcx.hir().local_def_id(anon_const.hir_id); + // NOTE(min_const_generics): We can't use `const_eval_poly` for constants + // as we currently do not supply the parent generics to anonymous constants + // but do allow `ConstKind::Param`. + // + // `const_eval_poly` tries to to first substitute generic parameters which + // results in an ICE while manually constructing the constant and using `eval` + // does nothing for `ConstKind::Param`. + let ct = ty::Const::from_anon_const(cx.tcx, def_id); + let param_env = cx.tcx.param_env(def_id); + print_const(cx, ct.eval(cx.tcx, param_env)) + } + }; + + Array(Box::new(clean_ty(ty, cx)), length) + } + TyKind::Tup(tys) => Tuple(tys.iter().map(|ty| clean_ty(ty, cx)).collect()), + TyKind::OpaqueDef(item_id, _) => { + let item = cx.tcx.hir().item(item_id); + if let hir::ItemKind::OpaqueTy(ref ty) = item.kind { + ImplTrait(ty.bounds.iter().filter_map(|x| x.clean(cx)).collect()) + } else { + unreachable!() + } + } + TyKind::Path(_) => clean_qpath(ty, cx), + TyKind::TraitObject(bounds, ref lifetime, _) => { + let bounds = bounds.iter().map(|bound| bound.clean(cx)).collect(); + let lifetime = + if !lifetime.is_elided() { Some(clean_lifetime(*lifetime, cx)) } else { None }; + DynTrait(bounds, lifetime) + } + TyKind::BareFn(barefn) => BareFunction(Box::new(barefn.clean(cx))), + // Rustdoc handles `TyKind::Err`s by turning them into `Type::Infer`s. + TyKind::Infer | TyKind::Err => Infer, + TyKind::Typeof(..) => panic!("unimplemented type {:?}", ty.kind), + } +} + +/// Returns `None` if the type could not be normalized +fn normalize<'tcx>(cx: &mut DocContext<'tcx>, ty: Ty<'_>) -> Option> { + // HACK: low-churn fix for #79459 while we wait for a trait normalization fix + if !cx.tcx.sess.opts.unstable_opts.normalize_docs { + return None; + } + + use crate::rustc_trait_selection::infer::TyCtxtInferExt; + use crate::rustc_trait_selection::traits::query::normalize::AtExt; + use rustc_middle::traits::ObligationCause; + + // Try to normalize `::T` to a type + let lifted = ty.lift_to_tcx(cx.tcx).unwrap(); + let normalized = cx.tcx.infer_ctxt().enter(|infcx| { + infcx + .at(&ObligationCause::dummy(), cx.param_env) + .normalize(lifted) + .map(|resolved| infcx.resolve_vars_if_possible(resolved.value)) + }); + match normalized { + Ok(normalized_value) => { + debug!("normalized {:?} to {:?}", ty, normalized_value); + Some(normalized_value) + } + Err(err) => { + debug!("failed to normalize {:?}: {:?}", ty, err); + None + } + } +} + +pub(crate) fn clean_middle_ty<'tcx>( + this: Ty<'tcx>, + cx: &mut DocContext<'tcx>, + def_id: Option, +) -> Type { + trace!("cleaning type: {:?}", this); + let ty = normalize(cx, this).unwrap_or(this); + match *ty.kind() { + ty::Never => Primitive(PrimitiveType::Never), + ty::Bool => Primitive(PrimitiveType::Bool), + ty::Char => Primitive(PrimitiveType::Char), + ty::Int(int_ty) => Primitive(int_ty.into()), + ty::Uint(uint_ty) => Primitive(uint_ty.into()), + ty::Float(float_ty) => Primitive(float_ty.into()), + ty::Str => Primitive(PrimitiveType::Str), + ty::Slice(ty) => Slice(Box::new(clean_middle_ty(ty, cx, None))), + ty::Array(ty, n) => { + let mut n = cx.tcx.lift(n).expect("array lift failed"); + n = n.eval(cx.tcx, ty::ParamEnv::reveal_all()); + let n = print_const(cx, n); + Array(Box::new(clean_middle_ty(ty, cx, None)), n) + } + ty::RawPtr(mt) => RawPointer(mt.mutbl, Box::new(clean_middle_ty(mt.ty, cx, None))), + ty::Ref(r, ty, mutbl) => BorrowedRef { + lifetime: clean_middle_region(r), + mutability: mutbl, + type_: Box::new(clean_middle_ty(ty, cx, None)), + }, + ty::FnDef(..) | ty::FnPtr(_) => { + let ty = cx.tcx.lift(this).expect("FnPtr lift failed"); + let sig = ty.fn_sig(cx.tcx); + let decl = clean_fn_decl_from_did_and_sig(cx, None, sig); + BareFunction(Box::new(BareFunctionDecl { + unsafety: sig.unsafety(), + generic_params: Vec::new(), + decl, + abi: sig.abi(), + })) + } + ty::Adt(def, substs) => { + let did = def.did(); + let kind = match def.adt_kind() { + AdtKind::Struct => ItemType::Struct, + AdtKind::Union => ItemType::Union, + AdtKind::Enum => ItemType::Enum, + }; + inline::record_extern_fqn(cx, did, kind); + let path = external_path(cx, did, false, vec![], substs); + Type::Path { path } + } + ty::Foreign(did) => { + inline::record_extern_fqn(cx, did, ItemType::ForeignType); + let path = external_path(cx, did, false, vec![], InternalSubsts::empty()); + Type::Path { path } + } + ty::Dynamic(obj, ref reg) => { + // HACK: pick the first `did` as the `did` of the trait object. Someone + // might want to implement "native" support for marker-trait-only + // trait objects. + let mut dids = obj.principal_def_id().into_iter().chain(obj.auto_traits()); + let did = dids + .next() + .unwrap_or_else(|| panic!("found trait object `{:?}` with no traits?", this)); + let substs = match obj.principal() { + Some(principal) => principal.skip_binder().substs, + // marker traits have no substs. + _ => cx.tcx.intern_substs(&[]), + }; + + inline::record_extern_fqn(cx, did, ItemType::Trait); + + let lifetime = clean_middle_region(*reg); + let mut bounds = vec![]; + + for did in dids { + let empty = cx.tcx.intern_substs(&[]); + let path = external_path(cx, did, false, vec![], empty); + inline::record_extern_fqn(cx, did, ItemType::Trait); + let bound = PolyTrait { trait_: path, generic_params: Vec::new() }; + bounds.push(bound); + } + + let mut bindings = vec![]; + for pb in obj.projection_bounds() { + bindings.push(TypeBinding { + assoc: projection_to_path_segment( + pb.skip_binder() + .lift_to_tcx(cx.tcx) + .unwrap() + // HACK(compiler-errors): Doesn't actually matter what self + // type we put here, because we're only using the GAT's substs. + .with_self_ty(cx.tcx, cx.tcx.types.self_param) + .projection_ty, + cx, + ), + kind: TypeBindingKind::Equality { + term: clean_middle_term(pb.skip_binder().term, cx), + }, + }); + } + + let path = external_path(cx, did, false, bindings, substs); + bounds.insert(0, PolyTrait { trait_: path, generic_params: Vec::new() }); + + DynTrait(bounds, lifetime) + } + ty::Tuple(t) => Tuple(t.iter().map(|t| clean_middle_ty(t, cx, None)).collect()), + + ty::Projection(ref data) => clean_projection(*data, cx, def_id), + + ty::Param(ref p) => { + if let Some(bounds) = cx.impl_trait_bounds.remove(&p.index.into()) { + ImplTrait(bounds) + } else { + Generic(p.name) + } + } + + ty::Opaque(def_id, substs) => { + // Grab the "TraitA + TraitB" from `impl TraitA + TraitB`, + // by looking up the bounds associated with the def_id. + let substs = cx.tcx.lift(substs).expect("Opaque lift failed"); + let bounds = cx + .tcx + .explicit_item_bounds(def_id) + .iter() + .map(|(bound, _)| EarlyBinder(*bound).subst(cx.tcx, substs)) + .collect::>(); + let mut regions = vec![]; + let mut has_sized = false; + let mut bounds = bounds + .iter() + .filter_map(|bound| { + let bound_predicate = bound.kind(); + let trait_ref = match bound_predicate.skip_binder() { + ty::PredicateKind::Trait(tr) => bound_predicate.rebind(tr.trait_ref), + ty::PredicateKind::TypeOutlives(ty::OutlivesPredicate(_ty, reg)) => { + if let Some(r) = clean_middle_region(reg) { + regions.push(GenericBound::Outlives(r)); + } + return None; + } + _ => return None, + }; + + if let Some(sized) = cx.tcx.lang_items().sized_trait() { + if trait_ref.def_id() == sized { + has_sized = true; + return None; + } + } + + let bindings: Vec<_> = bounds + .iter() + .filter_map(|bound| { + if let ty::PredicateKind::Projection(proj) = bound.kind().skip_binder() + { + if proj.projection_ty.trait_ref(cx.tcx) == trait_ref.skip_binder() { + Some(TypeBinding { + assoc: projection_to_path_segment(proj.projection_ty, cx), + kind: TypeBindingKind::Equality { + term: clean_middle_term(proj.term, cx), + }, + }) + } else { + None + } + } else { + None + } + }) + .collect(); + + Some(clean_poly_trait_ref_with_bindings(cx, trait_ref, &bindings)) + }) + .collect::>(); + bounds.extend(regions); + if !has_sized && !bounds.is_empty() { + bounds.insert(0, GenericBound::maybe_sized(cx)); + } + ImplTrait(bounds) + } + + ty::Closure(..) => panic!("Closure"), + ty::Generator(..) => panic!("Generator"), + ty::Bound(..) => panic!("Bound"), + ty::Placeholder(..) => panic!("Placeholder"), + ty::GeneratorWitness(..) => panic!("GeneratorWitness"), + ty::Infer(..) => panic!("Infer"), + ty::Error(_) => panic!("Error"), + } +} + +pub(crate) fn clean_field<'tcx>(field: &hir::FieldDef<'tcx>, cx: &mut DocContext<'tcx>) -> Item { + let def_id = cx.tcx.hir().local_def_id(field.hir_id).to_def_id(); + clean_field_with_def_id(def_id, field.ident.name, clean_ty(field.ty, cx), cx) +} + +pub(crate) fn clean_middle_field<'tcx>(field: &ty::FieldDef, cx: &mut DocContext<'tcx>) -> Item { + clean_field_with_def_id( + field.did, + field.name, + clean_middle_ty(cx.tcx.type_of(field.did), cx, Some(field.did)), + cx, + ) +} + +pub(crate) fn clean_field_with_def_id( + def_id: DefId, + name: Symbol, + ty: Type, + cx: &mut DocContext<'_>, +) -> Item { + let what_rustc_thinks = + Item::from_def_id_and_parts(def_id, Some(name), StructFieldItem(ty), cx); + if is_field_vis_inherited(cx.tcx, def_id) { + // Variant fields inherit their enum's visibility. + Item { visibility: Visibility::Inherited, ..what_rustc_thinks } + } else { + what_rustc_thinks + } +} + +fn is_field_vis_inherited(tcx: TyCtxt<'_>, def_id: DefId) -> bool { + let parent = tcx.parent(def_id); + match tcx.def_kind(parent) { + DefKind::Struct | DefKind::Union => false, + DefKind::Variant => true, + parent_kind => panic!("unexpected parent kind: {:?}", parent_kind), + } +} + +pub(crate) fn clean_visibility(vis: ty::Visibility) -> Visibility { + match vis { + ty::Visibility::Public => Visibility::Public, + // NOTE: this is not quite right: `ty` uses `Invisible` to mean 'private', + // while rustdoc really does mean inherited. That means that for enum variants, such as + // `pub enum E { V }`, `V` will be marked as `Public` by `ty`, but as `Inherited` by rustdoc. + // Various parts of clean override `tcx.visibility` explicitly to make sure this distinction is captured. + ty::Visibility::Invisible => Visibility::Inherited, + ty::Visibility::Restricted(module) => Visibility::Restricted(module), + } +} + +pub(crate) fn clean_variant_def<'tcx>(variant: &ty::VariantDef, cx: &mut DocContext<'tcx>) -> Item { + let kind = match variant.ctor_kind { + CtorKind::Const => Variant::CLike, + CtorKind::Fn => Variant::Tuple( + variant.fields.iter().map(|field| clean_middle_field(field, cx)).collect(), + ), + CtorKind::Fictive => Variant::Struct(VariantStruct { + struct_type: CtorKind::Fictive, + fields: variant.fields.iter().map(|field| clean_middle_field(field, cx)).collect(), + }), + }; + let what_rustc_thinks = + Item::from_def_id_and_parts(variant.def_id, Some(variant.name), VariantItem(kind), cx); + // don't show `pub` for variants, which always inherit visibility + Item { visibility: Inherited, ..what_rustc_thinks } +} + +fn clean_variant_data<'tcx>( + variant: &hir::VariantData<'tcx>, + cx: &mut DocContext<'tcx>, +) -> Variant { + match variant { + hir::VariantData::Struct(..) => Variant::Struct(VariantStruct { + struct_type: CtorKind::from_hir(variant), + fields: variant.fields().iter().map(|x| clean_field(x, cx)).collect(), + }), + hir::VariantData::Tuple(..) => { + Variant::Tuple(variant.fields().iter().map(|x| clean_field(x, cx)).collect()) + } + hir::VariantData::Unit(..) => Variant::CLike, + } +} + +fn clean_path<'tcx>(path: &hir::Path<'tcx>, cx: &mut DocContext<'tcx>) -> Path { + Path { res: path.res, segments: path.segments.iter().map(|x| x.clean(cx)).collect() } +} + +impl<'tcx> Clean<'tcx, GenericArgs> for hir::GenericArgs<'tcx> { + fn clean(&self, cx: &mut DocContext<'tcx>) -> GenericArgs { + if self.parenthesized { + let output = clean_ty(self.bindings[0].ty(), cx); + let output = + if output != Type::Tuple(Vec::new()) { Some(Box::new(output)) } else { None }; + let inputs = self.inputs().iter().map(|x| clean_ty(x, cx)).collect::>().into(); + GenericArgs::Parenthesized { inputs, output } + } else { + let args = self + .args + .iter() + .map(|arg| match arg { + hir::GenericArg::Lifetime(lt) if !lt.is_elided() => { + GenericArg::Lifetime(clean_lifetime(*lt, cx)) + } + hir::GenericArg::Lifetime(_) => GenericArg::Lifetime(Lifetime::elided()), + hir::GenericArg::Type(ty) => GenericArg::Type(clean_ty(ty, cx)), + hir::GenericArg::Const(ct) => GenericArg::Const(Box::new(clean_const(ct, cx))), + hir::GenericArg::Infer(_inf) => GenericArg::Infer, + }) + .collect::>() + .into(); + let bindings = + self.bindings.iter().map(|x| clean_type_binding(x, cx)).collect::>().into(); + GenericArgs::AngleBracketed { args, bindings } + } + } +} + +impl<'tcx> Clean<'tcx, PathSegment> for hir::PathSegment<'tcx> { + fn clean(&self, cx: &mut DocContext<'tcx>) -> PathSegment { + PathSegment { name: self.ident.name, args: self.args().clean(cx) } + } +} + +impl<'tcx> Clean<'tcx, BareFunctionDecl> for hir::BareFnTy<'tcx> { + fn clean(&self, cx: &mut DocContext<'tcx>) -> BareFunctionDecl { + let (generic_params, decl) = enter_impl_trait(cx, |cx| { + // NOTE: generics must be cleaned before args + let generic_params = self + .generic_params + .iter() + .filter(|p| !is_elided_lifetime(p)) + .map(|x| clean_generic_param(cx, None, x)) + .collect(); + let args = clean_args_from_types_and_names(cx, self.decl.inputs, self.param_names); + let decl = clean_fn_decl_with_args(cx, self.decl, args); + (generic_params, decl) + }); + BareFunctionDecl { unsafety: self.unsafety, abi: self.abi, decl, generic_params } + } +} + +fn clean_maybe_renamed_item<'tcx>( + cx: &mut DocContext<'tcx>, + item: &hir::Item<'tcx>, + renamed: Option, +) -> Vec { + use hir::ItemKind; + + let def_id = item.def_id.to_def_id(); + let mut name = renamed.unwrap_or_else(|| cx.tcx.hir().name(item.hir_id())); + cx.with_param_env(def_id, |cx| { + let kind = match item.kind { + ItemKind::Static(ty, mutability, body_id) => { + StaticItem(Static { type_: clean_ty(ty, cx), mutability, expr: Some(body_id) }) + } + ItemKind::Const(ty, body_id) => ConstantItem(Constant { + type_: clean_ty(ty, cx), + kind: ConstantKind::Local { body: body_id, def_id }, + }), + ItemKind::OpaqueTy(ref ty) => OpaqueTyItem(OpaqueTy { + bounds: ty.bounds.iter().filter_map(|x| x.clean(cx)).collect(), + generics: ty.generics.clean(cx), + }), + ItemKind::TyAlias(hir_ty, generics) => { + let rustdoc_ty = clean_ty(hir_ty, cx); + let ty = clean_middle_ty(hir_ty_to_ty(cx.tcx, hir_ty), cx, None); + TypedefItem(Box::new(Typedef { + type_: rustdoc_ty, + generics: generics.clean(cx), + item_type: Some(ty), + })) + } + ItemKind::Enum(ref def, generics) => EnumItem(Enum { + variants: def.variants.iter().map(|v| v.clean(cx)).collect(), + generics: generics.clean(cx), + }), + ItemKind::TraitAlias(generics, bounds) => TraitAliasItem(TraitAlias { + generics: generics.clean(cx), + bounds: bounds.iter().filter_map(|x| x.clean(cx)).collect(), + }), + ItemKind::Union(ref variant_data, generics) => UnionItem(Union { + generics: generics.clean(cx), + fields: variant_data.fields().iter().map(|x| clean_field(x, cx)).collect(), + }), + ItemKind::Struct(ref variant_data, generics) => StructItem(Struct { + struct_type: CtorKind::from_hir(variant_data), + generics: generics.clean(cx), + fields: variant_data.fields().iter().map(|x| clean_field(x, cx)).collect(), + }), + ItemKind::Impl(impl_) => return clean_impl(impl_, item.hir_id(), cx), + // proc macros can have a name set by attributes + ItemKind::Fn(ref sig, generics, body_id) => { + clean_fn_or_proc_macro(item, sig, generics, body_id, &mut name, cx) + } + ItemKind::Macro(ref macro_def, _) => { + let ty_vis = clean_visibility(cx.tcx.visibility(def_id)); + MacroItem(Macro { + source: display_macro_source(cx, name, macro_def, def_id, ty_vis), + }) + } + ItemKind::Trait(_, _, generics, bounds, item_ids) => { + let items = + item_ids.iter().map(|ti| cx.tcx.hir().trait_item(ti.id).clean(cx)).collect(); + + TraitItem(Trait { + def_id, + items, + generics: generics.clean(cx), + bounds: bounds.iter().filter_map(|x| x.clean(cx)).collect(), + }) + } + ItemKind::ExternCrate(orig_name) => { + return clean_extern_crate(item, name, orig_name, cx); + } + ItemKind::Use(path, kind) => { + return clean_use_statement(item, name, path, kind, cx, &mut FxHashSet::default()); + } + _ => unreachable!("not yet converted"), + }; + + vec![Item::from_def_id_and_parts(def_id, Some(name), kind, cx)] + }) +} + +impl<'tcx> Clean<'tcx, Item> for hir::Variant<'tcx> { + fn clean(&self, cx: &mut DocContext<'tcx>) -> Item { + let kind = VariantItem(clean_variant_data(&self.data, cx)); + let what_rustc_thinks = + Item::from_hir_id_and_parts(self.id, Some(self.ident.name), kind, cx); + // don't show `pub` for variants, which are always public + Item { visibility: Inherited, ..what_rustc_thinks } + } +} + +fn clean_impl<'tcx>( + impl_: &hir::Impl<'tcx>, + hir_id: hir::HirId, + cx: &mut DocContext<'tcx>, +) -> Vec { + let tcx = cx.tcx; + let mut ret = Vec::new(); + let trait_ = impl_.of_trait.as_ref().map(|t| clean_trait_ref(t, cx)); + let items = + impl_.items.iter().map(|ii| tcx.hir().impl_item(ii.id).clean(cx)).collect::>(); + let def_id = tcx.hir().local_def_id(hir_id); + + // If this impl block is an implementation of the Deref trait, then we + // need to try inlining the target's inherent impl blocks as well. + if trait_.as_ref().map(|t| t.def_id()) == tcx.lang_items().deref_trait() { + build_deref_target_impls(cx, &items, &mut ret); + } + + let for_ = clean_ty(impl_.self_ty, cx); + let type_alias = for_.def_id(&cx.cache).and_then(|did| match tcx.def_kind(did) { + DefKind::TyAlias => Some(clean_middle_ty(tcx.type_of(did), cx, Some(did))), + _ => None, + }); + let mut make_item = |trait_: Option, for_: Type, items: Vec| { + let kind = ImplItem(Box::new(Impl { + unsafety: impl_.unsafety, + generics: impl_.generics.clean(cx), + trait_, + for_, + items, + polarity: tcx.impl_polarity(def_id), + kind: if utils::has_doc_flag(tcx, def_id.to_def_id(), sym::fake_variadic) { + ImplKind::FakeVaradic + } else { + ImplKind::Normal + }, + })); + Item::from_hir_id_and_parts(hir_id, None, kind, cx) + }; + if let Some(type_alias) = type_alias { + ret.push(make_item(trait_.clone(), type_alias, items.clone())); + } + ret.push(make_item(trait_, for_, items)); + ret +} + +fn clean_extern_crate<'tcx>( + krate: &hir::Item<'tcx>, + name: Symbol, + orig_name: Option, + cx: &mut DocContext<'tcx>, +) -> Vec { + // this is the ID of the `extern crate` statement + let cnum = cx.tcx.extern_mod_stmt_cnum(krate.def_id).unwrap_or(LOCAL_CRATE); + // this is the ID of the crate itself + let crate_def_id = cnum.as_def_id(); + let attrs = cx.tcx.hir().attrs(krate.hir_id()); + let ty_vis = cx.tcx.visibility(krate.def_id); + let please_inline = ty_vis.is_public() + && attrs.iter().any(|a| { + a.has_name(sym::doc) + && match a.meta_item_list() { + Some(l) => attr::list_contains_name(&l, sym::inline), + None => false, + } + }); + + if please_inline { + let mut visited = FxHashSet::default(); + + let res = Res::Def(DefKind::Mod, crate_def_id); + + if let Some(items) = inline::try_inline( + cx, + cx.tcx.parent_module(krate.hir_id()).to_def_id(), + Some(krate.def_id.to_def_id()), + res, + name, + Some(attrs), + &mut visited, + ) { + return items; + } + } + + // FIXME: using `from_def_id_and_kind` breaks `rustdoc/masked` for some reason + vec![Item { + name: Some(name), + attrs: Box::new(Attributes::from_ast(attrs)), + item_id: crate_def_id.into(), + visibility: clean_visibility(ty_vis), + kind: Box::new(ExternCrateItem { src: orig_name }), + cfg: attrs.cfg(cx.tcx, &cx.cache.hidden_cfg), + }] +} + +fn clean_use_statement<'tcx>( + import: &hir::Item<'tcx>, + name: Symbol, + path: &hir::Path<'tcx>, + kind: hir::UseKind, + cx: &mut DocContext<'tcx>, + inlined_names: &mut FxHashSet<(ItemType, Symbol)>, +) -> Vec { + // We need this comparison because some imports (for std types for example) + // are "inserted" as well but directly by the compiler and they should not be + // taken into account. + if import.span.ctxt().outer_expn_data().kind == ExpnKind::AstPass(AstPass::StdImports) { + return Vec::new(); + } + + let visibility = cx.tcx.visibility(import.def_id); + let attrs = cx.tcx.hir().attrs(import.hir_id()); + let inline_attr = attrs.lists(sym::doc).get_word_attr(sym::inline); + let pub_underscore = visibility.is_public() && name == kw::Underscore; + let current_mod = cx.tcx.parent_module_from_def_id(import.def_id); + + // The parent of the module in which this import resides. This + // is the same as `current_mod` if that's already the top + // level module. + let parent_mod = cx.tcx.parent_module_from_def_id(current_mod); + + // This checks if the import can be seen from a higher level module. + // In other words, it checks if the visibility is the equivalent of + // `pub(super)` or higher. If the current module is the top level + // module, there isn't really a parent module, which makes the results + // meaningless. In this case, we make sure the answer is `false`. + let is_visible_from_parent_mod = visibility.is_accessible_from(parent_mod.to_def_id(), cx.tcx) + && !current_mod.is_top_level_module(); + + if pub_underscore { + if let Some(ref inline) = inline_attr { + rustc_errors::struct_span_err!( + cx.tcx.sess, + inline.span(), + E0780, + "anonymous imports cannot be inlined" + ) + .span_label(import.span, "anonymous import") + .emit(); + } + } + + // We consider inlining the documentation of `pub use` statements, but we + // forcefully don't inline if this is not public or if the + // #[doc(no_inline)] attribute is present. + // Don't inline doc(hidden) imports so they can be stripped at a later stage. + let mut denied = cx.output_format.is_json() + || !(visibility.is_public() + || (cx.render_options.document_private && is_visible_from_parent_mod)) + || pub_underscore + || attrs.iter().any(|a| { + a.has_name(sym::doc) + && match a.meta_item_list() { + Some(l) => { + attr::list_contains_name(&l, sym::no_inline) + || attr::list_contains_name(&l, sym::hidden) + } + None => false, + } + }); + + // Also check whether imports were asked to be inlined, in case we're trying to re-export a + // crate in Rust 2018+ + let path = clean_path(path, cx); + let inner = if kind == hir::UseKind::Glob { + if !denied { + let mut visited = FxHashSet::default(); + if let Some(items) = inline::try_inline_glob(cx, path.res, &mut visited, inlined_names) + { + return items; + } + } + Import::new_glob(resolve_use_source(cx, path), true) + } else { + if inline_attr.is_none() { + if let Res::Def(DefKind::Mod, did) = path.res { + if !did.is_local() && did.is_crate_root() { + // if we're `pub use`ing an extern crate root, don't inline it unless we + // were specifically asked for it + denied = true; + } + } + } + if !denied { + let mut visited = FxHashSet::default(); + let import_def_id = import.def_id.to_def_id(); + + if let Some(mut items) = inline::try_inline( + cx, + cx.tcx.parent_module(import.hir_id()).to_def_id(), + Some(import_def_id), + path.res, + name, + Some(attrs), + &mut visited, + ) { + items.push(Item::from_def_id_and_parts( + import_def_id, + None, + ImportItem(Import::new_simple(name, resolve_use_source(cx, path), false)), + cx, + )); + return items; + } + } + Import::new_simple(name, resolve_use_source(cx, path), true) + }; + + vec![Item::from_def_id_and_parts(import.def_id.to_def_id(), None, ImportItem(inner), cx)] +} + +fn clean_maybe_renamed_foreign_item<'tcx>( + cx: &mut DocContext<'tcx>, + item: &hir::ForeignItem<'tcx>, + renamed: Option, +) -> Item { + let def_id = item.def_id.to_def_id(); + cx.with_param_env(def_id, |cx| { + let kind = match item.kind { + hir::ForeignItemKind::Fn(decl, names, generics) => { + let (generics, decl) = enter_impl_trait(cx, |cx| { + // NOTE: generics must be cleaned before args + let generics = generics.clean(cx); + let args = clean_args_from_types_and_names(cx, decl.inputs, names); + let decl = clean_fn_decl_with_args(cx, decl, args); + (generics, decl) + }); + ForeignFunctionItem(Box::new(Function { decl, generics })) + } + hir::ForeignItemKind::Static(ty, mutability) => { + ForeignStaticItem(Static { type_: clean_ty(ty, cx), mutability, expr: None }) + } + hir::ForeignItemKind::Type => ForeignTypeItem, + }; + + Item::from_hir_id_and_parts( + item.hir_id(), + Some(renamed.unwrap_or(item.ident.name)), + kind, + cx, + ) + }) +} + +fn clean_type_binding<'tcx>( + type_binding: &hir::TypeBinding<'tcx>, + cx: &mut DocContext<'tcx>, +) -> TypeBinding { + TypeBinding { + assoc: PathSegment { name: type_binding.ident.name, args: type_binding.gen_args.clean(cx) }, + kind: match type_binding.kind { + hir::TypeBindingKind::Equality { ref term } => { + TypeBindingKind::Equality { term: clean_hir_term(term, cx) } + } + hir::TypeBindingKind::Constraint { bounds } => TypeBindingKind::Constraint { + bounds: bounds.iter().filter_map(|b| b.clean(cx)).collect(), + }, + }, + } +} diff --git a/src/librustdoc/clean/render_macro_matchers.rs b/src/librustdoc/clean/render_macro_matchers.rs new file mode 100644 index 000000000..ed7683e36 --- /dev/null +++ b/src/librustdoc/clean/render_macro_matchers.rs @@ -0,0 +1,238 @@ +use rustc_ast::token::{self, BinOpToken, Delimiter}; +use rustc_ast::tokenstream::{TokenStream, TokenTree}; +use rustc_ast_pretty::pprust::state::State as Printer; +use rustc_ast_pretty::pprust::PrintState; +use rustc_middle::ty::TyCtxt; +use rustc_session::parse::ParseSess; +use rustc_span::source_map::FilePathMapping; +use rustc_span::symbol::{kw, Ident, Symbol}; +use rustc_span::Span; + +/// Render a macro matcher in a format suitable for displaying to the user +/// as part of an item declaration. +pub(super) fn render_macro_matcher(tcx: TyCtxt<'_>, matcher: &TokenTree) -> String { + if let Some(snippet) = snippet_equal_to_token(tcx, matcher) { + // If the original source code is known, we display the matcher exactly + // as present in the source code. + return snippet; + } + + // If the matcher is macro-generated or some other reason the source code + // snippet is not available, we attempt to nicely render the token tree. + let mut printer = Printer::new(); + + // If the inner ibox fits on one line, we get: + // + // macro_rules! macroname { + // (the matcher) => {...}; + // } + // + // If the inner ibox gets wrapped, the cbox will break and get indented: + // + // macro_rules! macroname { + // ( + // the matcher ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~! + // ) => {...}; + // } + printer.cbox(8); + printer.word("("); + printer.zerobreak(); + printer.ibox(0); + match matcher { + TokenTree::Delimited(_span, _delim, tts) => print_tts(&mut printer, tts), + // Matcher which is not a Delimited is unexpected and should've failed + // to compile, but we render whatever it is wrapped in parens. + TokenTree::Token(..) => print_tt(&mut printer, matcher), + } + printer.end(); + printer.break_offset_if_not_bol(0, -4); + printer.word(")"); + printer.end(); + printer.s.eof() +} + +/// Find the source snippet for this token's Span, reparse it, and return the +/// snippet if the reparsed TokenTree matches the argument TokenTree. +fn snippet_equal_to_token(tcx: TyCtxt<'_>, matcher: &TokenTree) -> Option { + // Find what rustc thinks is the source snippet. + // This may not actually be anything meaningful if this matcher was itself + // generated by a macro. + let source_map = tcx.sess.source_map(); + let span = matcher.span(); + let snippet = source_map.span_to_snippet(span).ok()?; + + // Create a Parser. + let sess = ParseSess::new(FilePathMapping::empty()); + let file_name = source_map.span_to_filename(span); + let mut parser = + match rustc_parse::maybe_new_parser_from_source_str(&sess, file_name, snippet.clone()) { + Ok(parser) => parser, + Err(diagnostics) => { + drop(diagnostics); + return None; + } + }; + + // Reparse a single token tree. + let mut reparsed_trees = match parser.parse_all_token_trees() { + Ok(reparsed_trees) => reparsed_trees, + Err(diagnostic) => { + diagnostic.cancel(); + return None; + } + }; + if reparsed_trees.len() != 1 { + return None; + } + let reparsed_tree = reparsed_trees.pop().unwrap(); + + // Compare against the original tree. + if reparsed_tree.eq_unspanned(matcher) { Some(snippet) } else { None } +} + +fn print_tt(printer: &mut Printer<'_>, tt: &TokenTree) { + match tt { + TokenTree::Token(token, _) => { + let token_str = printer.token_to_string(token); + printer.word(token_str); + if let token::DocComment(..) = token.kind { + printer.hardbreak() + } + } + TokenTree::Delimited(_span, delim, tts) => { + let open_delim = printer.token_kind_to_string(&token::OpenDelim(*delim)); + printer.word(open_delim); + if !tts.is_empty() { + if *delim == Delimiter::Brace { + printer.space(); + } + print_tts(printer, tts); + if *delim == Delimiter::Brace { + printer.space(); + } + } + let close_delim = printer.token_kind_to_string(&token::CloseDelim(*delim)); + printer.word(close_delim); + } + } +} + +fn print_tts(printer: &mut Printer<'_>, tts: &TokenStream) { + #[derive(Copy, Clone, PartialEq)] + enum State { + Start, + Dollar, + DollarIdent, + DollarIdentColon, + DollarParen, + DollarParenSep, + Pound, + PoundBang, + Ident, + Other, + } + + use State::*; + + let mut state = Start; + for tt in tts.trees() { + let (needs_space, next_state) = match &tt { + TokenTree::Token(tt, _) => match (state, &tt.kind) { + (Dollar, token::Ident(..)) => (false, DollarIdent), + (DollarIdent, token::Colon) => (false, DollarIdentColon), + (DollarIdentColon, token::Ident(..)) => (false, Other), + ( + DollarParen, + token::BinOp(BinOpToken::Plus | BinOpToken::Star) | token::Question, + ) => (false, Other), + (DollarParen, _) => (false, DollarParenSep), + (DollarParenSep, token::BinOp(BinOpToken::Plus | BinOpToken::Star)) => { + (false, Other) + } + (Pound, token::Not) => (false, PoundBang), + (_, token::Ident(symbol, /* is_raw */ false)) + if !usually_needs_space_between_keyword_and_open_delim(*symbol, tt.span) => + { + (true, Ident) + } + (_, token::Comma | token::Semi) => (false, Other), + (_, token::Dollar) => (true, Dollar), + (_, token::Pound) => (true, Pound), + (_, _) => (true, Other), + }, + TokenTree::Delimited(_, delim, _) => match (state, delim) { + (Dollar, Delimiter::Parenthesis) => (false, DollarParen), + (Pound | PoundBang, Delimiter::Bracket) => (false, Other), + (Ident, Delimiter::Parenthesis | Delimiter::Bracket) => (false, Other), + (_, _) => (true, Other), + }, + }; + if state != Start && needs_space { + printer.space(); + } + print_tt(printer, tt); + state = next_state; + } +} + +fn usually_needs_space_between_keyword_and_open_delim(symbol: Symbol, span: Span) -> bool { + let ident = Ident { name: symbol, span }; + let is_keyword = ident.is_used_keyword() || ident.is_unused_keyword(); + if !is_keyword { + // An identifier that is not a keyword usually does not need a space + // before an open delim. For example: `f(0)` or `f[0]`. + return false; + } + + match symbol { + // No space after keywords that are syntactically an expression. For + // example: a tuple struct created with `let _ = Self(0, 0)`, or if + // someone has `impl Index for bool` then `true[MyStruct]`. + kw::False | kw::SelfLower | kw::SelfUpper | kw::True => false, + + // No space, as in `let _: fn();` + kw::Fn => false, + + // No space, as in `pub(crate) type T;` + kw::Pub => false, + + // No space for keywords that can end an expression, as in `fut.await()` + // where fut's Output type is `fn()`. + kw::Await => false, + + // Otherwise space after keyword. Some examples: + // + // `expr as [T; 2]` + // ^ + // `box (tuple,)` + // ^ + // `break (tuple,)` + // ^ + // `type T = dyn (Fn() -> dyn Trait) + Send;` + // ^ + // `for (tuple,) in iter {}` + // ^ + // `if (tuple,) == v {}` + // ^ + // `impl [T] {}` + // ^ + // `for x in [..] {}` + // ^ + // `let () = unit;` + // ^ + // `match [x, y] {...}` + // ^ + // `&mut (x as T)` + // ^ + // `return [];` + // ^ + // `fn f() where (): Into` + // ^ + // `while (a + b).what() {}` + // ^ + // `yield [];` + // ^ + _ => true, + } +} diff --git a/src/librustdoc/clean/simplify.rs b/src/librustdoc/clean/simplify.rs new file mode 100644 index 000000000..af7813a77 --- /dev/null +++ b/src/librustdoc/clean/simplify.rs @@ -0,0 +1,139 @@ +//! Simplification of where-clauses and parameter bounds into a prettier and +//! more canonical form. +//! +//! Currently all cross-crate-inlined function use `rustc_middle::ty` to reconstruct +//! the AST (e.g., see all of `clean::inline`), but this is not always a +//! non-lossy transformation. The current format of storage for where-clauses +//! for functions and such is simply a list of predicates. One example of this +//! is that the AST predicate of: `where T: Trait` is encoded as: +//! `where T: Trait, ::Foo = Bar`. +//! +//! This module attempts to reconstruct the original where and/or parameter +//! bounds by special casing scenarios such as these. Fun! + +use rustc_data_structures::fx::FxIndexMap; +use rustc_hir::def_id::DefId; +use rustc_middle::ty; +use rustc_span::Symbol; + +use crate::clean; +use crate::clean::GenericArgs as PP; +use crate::clean::WherePredicate as WP; +use crate::core::DocContext; + +pub(crate) fn where_clauses(cx: &DocContext<'_>, clauses: Vec) -> Vec { + // First, partition the where clause into its separate components. + // + // We use `FxIndexMap` so that the insertion order is preserved to prevent messing up to + // the order of the generated bounds. + let mut params: FxIndexMap, Vec<_>)> = FxIndexMap::default(); + let mut lifetimes = Vec::new(); + let mut equalities = Vec::new(); + let mut tybounds = Vec::new(); + + for clause in clauses { + match clause { + WP::BoundPredicate { ty, bounds, bound_params } => match ty { + clean::Generic(s) => { + let (b, p) = params.entry(s).or_default(); + b.extend(bounds); + p.extend(bound_params); + } + t => tybounds.push((t, (bounds, bound_params))), + }, + WP::RegionPredicate { lifetime, bounds } => { + lifetimes.push((lifetime, bounds)); + } + WP::EqPredicate { lhs, rhs } => equalities.push((lhs, rhs)), + } + } + + // Look for equality predicates on associated types that can be merged into + // general bound predicates + equalities.retain(|&(ref lhs, ref rhs)| { + let Some((self_, trait_did, name)) = lhs.projection() else { + return true; + }; + let clean::Generic(generic) = self_ else { return true }; + let Some((bounds, _)) = params.get_mut(generic) else { return true }; + + merge_bounds(cx, bounds, trait_did, name, rhs) + }); + + // And finally, let's reassemble everything + let mut clauses = Vec::new(); + clauses.extend( + lifetimes.into_iter().map(|(lt, bounds)| WP::RegionPredicate { lifetime: lt, bounds }), + ); + clauses.extend(params.into_iter().map(|(k, (bounds, params))| WP::BoundPredicate { + ty: clean::Generic(k), + bounds, + bound_params: params, + })); + clauses.extend(tybounds.into_iter().map(|(ty, (bounds, bound_params))| WP::BoundPredicate { + ty, + bounds, + bound_params, + })); + clauses.extend(equalities.into_iter().map(|(lhs, rhs)| WP::EqPredicate { lhs, rhs })); + clauses +} + +pub(crate) fn merge_bounds( + cx: &clean::DocContext<'_>, + bounds: &mut Vec, + trait_did: DefId, + assoc: clean::PathSegment, + rhs: &clean::Term, +) -> bool { + !bounds.iter_mut().any(|b| { + let trait_ref = match *b { + clean::GenericBound::TraitBound(ref mut tr, _) => tr, + clean::GenericBound::Outlives(..) => return false, + }; + // If this QPath's trait `trait_did` is the same as, or a supertrait + // of, the bound's trait `did` then we can keep going, otherwise + // this is just a plain old equality bound. + if !trait_is_same_or_supertrait(cx, trait_ref.trait_.def_id(), trait_did) { + return false; + } + let last = trait_ref.trait_.segments.last_mut().expect("segments were empty"); + match last.args { + PP::AngleBracketed { ref mut bindings, .. } => { + bindings.push(clean::TypeBinding { + assoc: assoc.clone(), + kind: clean::TypeBindingKind::Equality { term: rhs.clone() }, + }); + } + PP::Parenthesized { ref mut output, .. } => match output { + Some(o) => assert_eq!(&clean::Term::Type(o.as_ref().clone()), rhs), + None => { + if *rhs != clean::Term::Type(clean::Type::Tuple(Vec::new())) { + *output = Some(Box::new(rhs.ty().unwrap().clone())); + } + } + }, + }; + true + }) +} + +fn trait_is_same_or_supertrait(cx: &DocContext<'_>, child: DefId, trait_: DefId) -> bool { + if child == trait_ { + return true; + } + let predicates = cx.tcx.super_predicates_of(child); + debug_assert!(cx.tcx.generics_of(child).has_self); + let self_ty = cx.tcx.types.self_param; + predicates + .predicates + .iter() + .filter_map(|(pred, _)| { + if let ty::PredicateKind::Trait(pred) = pred.kind().skip_binder() { + if pred.trait_ref.self_ty() == self_ty { Some(pred.def_id()) } else { None } + } else { + None + } + }) + .any(|did| trait_is_same_or_supertrait(cx, did, trait_)) +} diff --git a/src/librustdoc/clean/types.rs b/src/librustdoc/clean/types.rs new file mode 100644 index 000000000..0e6de842c --- /dev/null +++ b/src/librustdoc/clean/types.rs @@ -0,0 +1,2508 @@ +use std::cell::RefCell; +use std::default::Default; +use std::hash::Hash; +use std::path::PathBuf; +use std::rc::Rc; +use std::sync::Arc; +use std::sync::OnceLock as OnceCell; +use std::{cmp, fmt, iter}; + +use arrayvec::ArrayVec; + +use rustc_ast::attr; +use rustc_ast::util::comments::beautify_doc_string; +use rustc_ast::{self as ast, AttrStyle}; +use rustc_attr::{ConstStability, Deprecation, Stability, StabilityLevel}; +use rustc_const_eval::const_eval::is_unstable_const_fn; +use rustc_data_structures::fx::{FxHashMap, FxHashSet}; +use rustc_data_structures::thin_vec::ThinVec; +use rustc_hir as hir; +use rustc_hir::def::{CtorKind, DefKind, Res}; +use rustc_hir::def_id::{CrateNum, DefId, LOCAL_CRATE}; +use rustc_hir::lang_items::LangItem; +use rustc_hir::{BodyId, Mutability}; +use rustc_index::vec::IndexVec; +use rustc_middle::ty::fast_reject::SimplifiedType; +use rustc_middle::ty::{self, TyCtxt}; +use rustc_session::Session; +use rustc_span::hygiene::MacroKind; +use rustc_span::source_map::DUMMY_SP; +use rustc_span::symbol::{kw, sym, Ident, Symbol}; +use rustc_span::{self, FileName, Loc}; +use rustc_target::abi::VariantIdx; +use rustc_target::spec::abi::Abi; +use rustc_typeck::check::intrinsic::intrinsic_operation_unsafety; + +use crate::clean::cfg::Cfg; +use crate::clean::clean_visibility; +use crate::clean::external_path; +use crate::clean::inline::{self, print_inlined_const}; +use crate::clean::utils::{is_literal_expr, print_const_expr, print_evaluated_const}; +use crate::core::DocContext; +use crate::formats::cache::Cache; +use crate::formats::item_type::ItemType; +use crate::html::render::Context; +use crate::passes::collect_intra_doc_links::UrlFragment; + +pub(crate) use self::FnRetTy::*; +pub(crate) use self::ItemKind::*; +pub(crate) use self::SelfTy::*; +pub(crate) use self::Type::{ + Array, BareFunction, BorrowedRef, DynTrait, Generic, ImplTrait, Infer, Primitive, QPath, + RawPointer, Slice, Tuple, +}; +pub(crate) use self::Visibility::{Inherited, Public}; + +#[cfg(test)] +mod tests; + +pub(crate) type ItemIdSet = FxHashSet; + +#[derive(Debug, Clone, PartialEq, Eq, Hash, Copy)] +pub(crate) enum ItemId { + /// A "normal" item that uses a [`DefId`] for identification. + DefId(DefId), + /// Identifier that is used for auto traits. + Auto { trait_: DefId, for_: DefId }, + /// Identifier that is used for blanket implementations. + Blanket { impl_id: DefId, for_: DefId }, + /// Identifier for primitive types. + Primitive(PrimitiveType, CrateNum), +} + +impl ItemId { + #[inline] + pub(crate) fn is_local(self) -> bool { + match self { + ItemId::Auto { for_: id, .. } + | ItemId::Blanket { for_: id, .. } + | ItemId::DefId(id) => id.is_local(), + ItemId::Primitive(_, krate) => krate == LOCAL_CRATE, + } + } + + #[inline] + #[track_caller] + pub(crate) fn expect_def_id(self) -> DefId { + self.as_def_id() + .unwrap_or_else(|| panic!("ItemId::expect_def_id: `{:?}` isn't a DefId", self)) + } + + #[inline] + pub(crate) fn as_def_id(self) -> Option { + match self { + ItemId::DefId(id) => Some(id), + _ => None, + } + } + + #[inline] + pub(crate) fn krate(self) -> CrateNum { + match self { + ItemId::Auto { for_: id, .. } + | ItemId::Blanket { for_: id, .. } + | ItemId::DefId(id) => id.krate, + ItemId::Primitive(_, krate) => krate, + } + } +} + +impl From for ItemId { + fn from(id: DefId) -> Self { + Self::DefId(id) + } +} + +/// The crate currently being documented. +#[derive(Clone, Debug)] +pub(crate) struct Crate { + pub(crate) module: Item, + pub(crate) primitives: ThinVec<(DefId, PrimitiveType)>, + /// Only here so that they can be filtered through the rustdoc passes. + pub(crate) external_traits: Rc>>, +} + +impl Crate { + pub(crate) fn name(&self, tcx: TyCtxt<'_>) -> Symbol { + ExternalCrate::LOCAL.name(tcx) + } + + pub(crate) fn src(&self, tcx: TyCtxt<'_>) -> FileName { + ExternalCrate::LOCAL.src(tcx) + } +} + +/// This struct is used to wrap additional information added by rustdoc on a `trait` item. +#[derive(Clone, Debug)] +pub(crate) struct TraitWithExtraInfo { + pub(crate) trait_: Trait, + pub(crate) is_notable: bool, +} + +#[derive(Copy, Clone, Debug)] +pub(crate) struct ExternalCrate { + pub(crate) crate_num: CrateNum, +} + +impl ExternalCrate { + const LOCAL: Self = Self { crate_num: LOCAL_CRATE }; + + #[inline] + pub(crate) fn def_id(&self) -> DefId { + self.crate_num.as_def_id() + } + + pub(crate) fn src(&self, tcx: TyCtxt<'_>) -> FileName { + let krate_span = tcx.def_span(self.def_id()); + tcx.sess.source_map().span_to_filename(krate_span) + } + + pub(crate) fn name(&self, tcx: TyCtxt<'_>) -> Symbol { + tcx.crate_name(self.crate_num) + } + + pub(crate) fn src_root(&self, tcx: TyCtxt<'_>) -> PathBuf { + match self.src(tcx) { + FileName::Real(ref p) => match p.local_path_if_available().parent() { + Some(p) => p.to_path_buf(), + None => PathBuf::new(), + }, + _ => PathBuf::new(), + } + } + + /// Attempts to find where an external crate is located, given that we're + /// rendering in to the specified source destination. + pub(crate) fn location( + &self, + extern_url: Option<&str>, + extern_url_takes_precedence: bool, + dst: &std::path::Path, + tcx: TyCtxt<'_>, + ) -> ExternalLocation { + use ExternalLocation::*; + + fn to_remote(url: impl ToString) -> ExternalLocation { + let mut url = url.to_string(); + if !url.ends_with('/') { + url.push('/'); + } + Remote(url) + } + + // See if there's documentation generated into the local directory + // WARNING: since rustdoc creates these directories as it generates documentation, this check is only accurate before rendering starts. + // Make sure to call `location()` by that time. + let local_location = dst.join(self.name(tcx).as_str()); + if local_location.is_dir() { + return Local; + } + + if extern_url_takes_precedence { + if let Some(url) = extern_url { + return to_remote(url); + } + } + + // Failing that, see if there's an attribute specifying where to find this + // external crate + let did = self.crate_num.as_def_id(); + tcx.get_attrs(did, sym::doc) + .flat_map(|attr| attr.meta_item_list().unwrap_or_default()) + .filter(|a| a.has_name(sym::html_root_url)) + .filter_map(|a| a.value_str()) + .map(to_remote) + .next() + .or_else(|| extern_url.map(to_remote)) // NOTE: only matters if `extern_url_takes_precedence` is false + .unwrap_or(Unknown) // Well, at least we tried. + } + + pub(crate) fn keywords(&self, tcx: TyCtxt<'_>) -> ThinVec<(DefId, Symbol)> { + let root = self.def_id(); + + let as_keyword = |res: Res| { + if let Res::Def(DefKind::Mod, def_id) = res { + let mut keyword = None; + let meta_items = tcx + .get_attrs(def_id, sym::doc) + .flat_map(|attr| attr.meta_item_list().unwrap_or_default()); + for meta in meta_items { + if meta.has_name(sym::keyword) { + if let Some(v) = meta.value_str() { + keyword = Some(v); + break; + } + } + } + return keyword.map(|p| (def_id, p)); + } + None + }; + if root.is_local() { + tcx.hir() + .root_module() + .item_ids + .iter() + .filter_map(|&id| { + let item = tcx.hir().item(id); + match item.kind { + hir::ItemKind::Mod(_) => { + as_keyword(Res::Def(DefKind::Mod, id.def_id.to_def_id())) + } + hir::ItemKind::Use(path, hir::UseKind::Single) + if tcx.visibility(id.def_id).is_public() => + { + as_keyword(path.res.expect_non_local()) + .map(|(_, prim)| (id.def_id.to_def_id(), prim)) + } + _ => None, + } + }) + .collect() + } else { + tcx.module_children(root).iter().map(|item| item.res).filter_map(as_keyword).collect() + } + } + + pub(crate) fn primitives(&self, tcx: TyCtxt<'_>) -> ThinVec<(DefId, PrimitiveType)> { + let root = self.def_id(); + + // Collect all inner modules which are tagged as implementations of + // primitives. + // + // Note that this loop only searches the top-level items of the crate, + // and this is intentional. If we were to search the entire crate for an + // item tagged with `#[doc(primitive)]` then we would also have to + // search the entirety of external modules for items tagged + // `#[doc(primitive)]`, which is a pretty inefficient process (decoding + // all that metadata unconditionally). + // + // In order to keep the metadata load under control, the + // `#[doc(primitive)]` feature is explicitly designed to only allow the + // primitive tags to show up as the top level items in a crate. + // + // Also note that this does not attempt to deal with modules tagged + // duplicately for the same primitive. This is handled later on when + // rendering by delegating everything to a hash map. + let as_primitive = |res: Res| { + if let Res::Def(DefKind::Mod, def_id) = res { + let mut prim = None; + let meta_items = tcx + .get_attrs(def_id, sym::doc) + .flat_map(|attr| attr.meta_item_list().unwrap_or_default()); + for meta in meta_items { + if let Some(v) = meta.value_str() { + if meta.has_name(sym::primitive) { + prim = PrimitiveType::from_symbol(v); + if prim.is_some() { + break; + } + // FIXME: should warn on unknown primitives? + } + } + } + return prim.map(|p| (def_id, p)); + } + None + }; + + if root.is_local() { + tcx.hir() + .root_module() + .item_ids + .iter() + .filter_map(|&id| { + let item = tcx.hir().item(id); + match item.kind { + hir::ItemKind::Mod(_) => { + as_primitive(Res::Def(DefKind::Mod, id.def_id.to_def_id())) + } + hir::ItemKind::Use(path, hir::UseKind::Single) + if tcx.visibility(id.def_id).is_public() => + { + as_primitive(path.res.expect_non_local()).map(|(_, prim)| { + // Pretend the primitive is local. + (id.def_id.to_def_id(), prim) + }) + } + _ => None, + } + }) + .collect() + } else { + tcx.module_children(root).iter().map(|item| item.res).filter_map(as_primitive).collect() + } + } +} + +/// Indicates where an external crate can be found. +#[derive(Debug)] +pub(crate) enum ExternalLocation { + /// Remote URL root of the external crate + Remote(String), + /// This external crate can be found in the local doc/ folder + Local, + /// The external crate could not be found. + Unknown, +} + +/// Anything with a source location and set of attributes and, optionally, a +/// name. That is, anything that can be documented. This doesn't correspond +/// directly to the AST's concept of an item; it's a strict superset. +#[derive(Clone)] +pub(crate) struct Item { + /// The name of this item. + /// Optional because not every item has a name, e.g. impls. + pub(crate) name: Option, + pub(crate) attrs: Box, + pub(crate) visibility: Visibility, + /// Information about this item that is specific to what kind of item it is. + /// E.g., struct vs enum vs function. + pub(crate) kind: Box, + pub(crate) item_id: ItemId, + + pub(crate) cfg: Option>, +} + +/// NOTE: this does NOT unconditionally print every item, to avoid thousands of lines of logs. +/// If you want to see the debug output for attributes and the `kind` as well, use `{:#?}` instead of `{:?}`. +impl fmt::Debug for Item { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + let alternate = f.alternate(); + // hand-picked fields that don't bloat the logs too much + let mut fmt = f.debug_struct("Item"); + fmt.field("name", &self.name) + .field("visibility", &self.visibility) + .field("item_id", &self.item_id); + // allow printing the full item if someone really wants to + if alternate { + fmt.field("attrs", &self.attrs).field("kind", &self.kind).field("cfg", &self.cfg); + } else { + fmt.field("kind", &self.type_()); + fmt.field("docs", &self.doc_value()); + } + fmt.finish() + } +} + +pub(crate) fn rustc_span(def_id: DefId, tcx: TyCtxt<'_>) -> Span { + Span::new(def_id.as_local().map_or_else( + || tcx.def_span(def_id), + |local| { + let hir = tcx.hir(); + hir.span_with_body(hir.local_def_id_to_hir_id(local)) + }, + )) +} + +impl Item { + pub(crate) fn stability<'tcx>(&self, tcx: TyCtxt<'tcx>) -> Option { + self.item_id.as_def_id().and_then(|did| tcx.lookup_stability(did)) + } + + pub(crate) fn const_stability<'tcx>(&self, tcx: TyCtxt<'tcx>) -> Option { + self.item_id.as_def_id().and_then(|did| tcx.lookup_const_stability(did)) + } + + pub(crate) fn deprecation(&self, tcx: TyCtxt<'_>) -> Option { + self.item_id.as_def_id().and_then(|did| tcx.lookup_deprecation(did)) + } + + pub(crate) fn inner_docs(&self, tcx: TyCtxt<'_>) -> bool { + self.item_id + .as_def_id() + .map(|did| tcx.get_attrs_unchecked(did).inner_docs()) + .unwrap_or(false) + } + + pub(crate) fn span(&self, tcx: TyCtxt<'_>) -> Span { + let kind = match &*self.kind { + ItemKind::StrippedItem(k) => k, + _ => &*self.kind, + }; + match kind { + ItemKind::ModuleItem(Module { span, .. }) => *span, + ItemKind::ImplItem(box Impl { kind: ImplKind::Auto, .. }) => Span::dummy(), + ItemKind::ImplItem(box Impl { kind: ImplKind::Blanket(_), .. }) => { + if let ItemId::Blanket { impl_id, .. } = self.item_id { + rustc_span(impl_id, tcx) + } else { + panic!("blanket impl item has non-blanket ID") + } + } + _ => { + self.item_id.as_def_id().map(|did| rustc_span(did, tcx)).unwrap_or_else(Span::dummy) + } + } + } + + pub(crate) fn attr_span(&self, tcx: TyCtxt<'_>) -> rustc_span::Span { + crate::passes::span_of_attrs(&self.attrs).unwrap_or_else(|| self.span(tcx).inner()) + } + + /// Finds the `doc` attribute as a NameValue and returns the corresponding + /// value found. + pub(crate) fn doc_value(&self) -> Option { + self.attrs.doc_value() + } + + /// Convenience wrapper around [`Self::from_def_id_and_parts`] which converts + /// `hir_id` to a [`DefId`] + pub(crate) fn from_hir_id_and_parts( + hir_id: hir::HirId, + name: Option, + kind: ItemKind, + cx: &mut DocContext<'_>, + ) -> Item { + Item::from_def_id_and_parts(cx.tcx.hir().local_def_id(hir_id).to_def_id(), name, kind, cx) + } + + pub(crate) fn from_def_id_and_parts( + def_id: DefId, + name: Option, + kind: ItemKind, + cx: &mut DocContext<'_>, + ) -> Item { + let ast_attrs = cx.tcx.get_attrs_unchecked(def_id); + + Self::from_def_id_and_attrs_and_parts( + def_id, + name, + kind, + Box::new(Attributes::from_ast(ast_attrs)), + cx, + ast_attrs.cfg(cx.tcx, &cx.cache.hidden_cfg), + ) + } + + pub(crate) fn from_def_id_and_attrs_and_parts( + def_id: DefId, + name: Option, + kind: ItemKind, + attrs: Box, + cx: &mut DocContext<'_>, + cfg: Option>, + ) -> Item { + trace!("name={:?}, def_id={:?}", name, def_id); + + // Primitives and Keywords are written in the source code as private modules. + // The modules need to be private so that nobody actually uses them, but the + // keywords and primitives that they are documenting are public. + let visibility = if matches!(&kind, ItemKind::KeywordItem | ItemKind::PrimitiveItem(..)) { + Visibility::Public + } else { + clean_visibility(cx.tcx.visibility(def_id)) + }; + + Item { item_id: def_id.into(), kind: Box::new(kind), name, attrs, visibility, cfg } + } + + /// Finds all `doc` attributes as NameValues and returns their corresponding values, joined + /// with newlines. + pub(crate) fn collapsed_doc_value(&self) -> Option { + self.attrs.collapsed_doc_value() + } + + pub(crate) fn links(&self, cx: &Context<'_>) -> Vec { + use crate::html::format::href; + + cx.cache() + .intra_doc_links + .get(&self.item_id) + .map_or(&[][..], |v| v.as_slice()) + .iter() + .filter_map(|ItemLink { link: s, link_text, did, ref fragment }| { + debug!(?did); + if let Ok((mut href, ..)) = href(*did, cx) { + debug!(?href); + if let Some(ref fragment) = *fragment { + fragment.render(&mut href, cx.tcx()) + } + Some(RenderedLink { + original_text: s.clone(), + new_text: link_text.clone(), + href, + }) + } else { + None + } + }) + .collect() + } + + /// Find a list of all link names, without finding their href. + /// + /// This is used for generating summary text, which does not include + /// the link text, but does need to know which `[]`-bracketed names + /// are actually links. + pub(crate) fn link_names(&self, cache: &Cache) -> Vec { + cache + .intra_doc_links + .get(&self.item_id) + .map_or(&[][..], |v| v.as_slice()) + .iter() + .map(|ItemLink { link: s, link_text, .. }| RenderedLink { + original_text: s.clone(), + new_text: link_text.clone(), + href: String::new(), + }) + .collect() + } + + pub(crate) fn is_crate(&self) -> bool { + self.is_mod() && self.item_id.as_def_id().map_or(false, |did| did.is_crate_root()) + } + pub(crate) fn is_mod(&self) -> bool { + self.type_() == ItemType::Module + } + pub(crate) fn is_trait(&self) -> bool { + self.type_() == ItemType::Trait + } + pub(crate) fn is_struct(&self) -> bool { + self.type_() == ItemType::Struct + } + pub(crate) fn is_enum(&self) -> bool { + self.type_() == ItemType::Enum + } + pub(crate) fn is_variant(&self) -> bool { + self.type_() == ItemType::Variant + } + pub(crate) fn is_associated_type(&self) -> bool { + matches!(&*self.kind, AssocTypeItem(..) | StrippedItem(box AssocTypeItem(..))) + } + pub(crate) fn is_ty_associated_type(&self) -> bool { + matches!(&*self.kind, TyAssocTypeItem(..) | StrippedItem(box TyAssocTypeItem(..))) + } + pub(crate) fn is_associated_const(&self) -> bool { + matches!(&*self.kind, AssocConstItem(..) | StrippedItem(box AssocConstItem(..))) + } + pub(crate) fn is_ty_associated_const(&self) -> bool { + matches!(&*self.kind, TyAssocConstItem(..) | StrippedItem(box TyAssocConstItem(..))) + } + pub(crate) fn is_method(&self) -> bool { + self.type_() == ItemType::Method + } + pub(crate) fn is_ty_method(&self) -> bool { + self.type_() == ItemType::TyMethod + } + pub(crate) fn is_typedef(&self) -> bool { + self.type_() == ItemType::Typedef + } + pub(crate) fn is_primitive(&self) -> bool { + self.type_() == ItemType::Primitive + } + pub(crate) fn is_union(&self) -> bool { + self.type_() == ItemType::Union + } + pub(crate) fn is_import(&self) -> bool { + self.type_() == ItemType::Import + } + pub(crate) fn is_extern_crate(&self) -> bool { + self.type_() == ItemType::ExternCrate + } + pub(crate) fn is_keyword(&self) -> bool { + self.type_() == ItemType::Keyword + } + pub(crate) fn is_stripped(&self) -> bool { + match *self.kind { + StrippedItem(..) => true, + ImportItem(ref i) => !i.should_be_displayed, + _ => false, + } + } + pub(crate) fn has_stripped_entries(&self) -> Option { + match *self.kind { + StructItem(ref struct_) => Some(struct_.has_stripped_entries()), + UnionItem(ref union_) => Some(union_.has_stripped_entries()), + EnumItem(ref enum_) => Some(enum_.has_stripped_entries()), + VariantItem(ref v) => v.has_stripped_entries(), + _ => None, + } + } + + pub(crate) fn stability_class(&self, tcx: TyCtxt<'_>) -> Option { + self.stability(tcx).as_ref().and_then(|s| { + let mut classes = Vec::with_capacity(2); + + if s.is_unstable() { + classes.push("unstable"); + } + + // FIXME: what about non-staged API items that are deprecated? + if self.deprecation(tcx).is_some() { + classes.push("deprecated"); + } + + if !classes.is_empty() { Some(classes.join(" ")) } else { None } + }) + } + + pub(crate) fn stable_since(&self, tcx: TyCtxt<'_>) -> Option { + match self.stability(tcx)?.level { + StabilityLevel::Stable { since, .. } => Some(since), + StabilityLevel::Unstable { .. } => None, + } + } + + pub(crate) fn const_stable_since(&self, tcx: TyCtxt<'_>) -> Option { + match self.const_stability(tcx)?.level { + StabilityLevel::Stable { since, .. } => Some(since), + StabilityLevel::Unstable { .. } => None, + } + } + + pub(crate) fn is_non_exhaustive(&self) -> bool { + self.attrs.other_attrs.iter().any(|a| a.has_name(sym::non_exhaustive)) + } + + /// Returns a documentation-level item type from the item. + pub(crate) fn type_(&self) -> ItemType { + ItemType::from(self) + } + + pub(crate) fn is_default(&self) -> bool { + match *self.kind { + ItemKind::MethodItem(_, Some(defaultness)) => { + defaultness.has_value() && !defaultness.is_final() + } + _ => false, + } + } + + /// Returns a `FnHeader` if `self` is a function item, otherwise returns `None`. + pub(crate) fn fn_header(&self, tcx: TyCtxt<'_>) -> Option { + fn build_fn_header( + def_id: DefId, + tcx: TyCtxt<'_>, + asyncness: hir::IsAsync, + ) -> hir::FnHeader { + let sig = tcx.fn_sig(def_id); + let constness = + if tcx.is_const_fn(def_id) && is_unstable_const_fn(tcx, def_id).is_none() { + hir::Constness::Const + } else { + hir::Constness::NotConst + }; + hir::FnHeader { unsafety: sig.unsafety(), abi: sig.abi(), constness, asyncness } + } + let header = match *self.kind { + ItemKind::ForeignFunctionItem(_) => { + let abi = tcx.fn_sig(self.item_id.as_def_id().unwrap()).abi(); + hir::FnHeader { + unsafety: if abi == Abi::RustIntrinsic { + intrinsic_operation_unsafety(self.name.unwrap()) + } else { + hir::Unsafety::Unsafe + }, + abi, + constness: hir::Constness::NotConst, + asyncness: hir::IsAsync::NotAsync, + } + } + ItemKind::FunctionItem(_) | ItemKind::MethodItem(_, _) => { + let def_id = self.item_id.as_def_id().unwrap(); + build_fn_header(def_id, tcx, tcx.asyncness(def_id)) + } + ItemKind::TyMethodItem(_) => { + build_fn_header(self.item_id.as_def_id().unwrap(), tcx, hir::IsAsync::NotAsync) + } + _ => return None, + }; + Some(header) + } +} + +#[derive(Clone, Debug)] +pub(crate) enum ItemKind { + ExternCrateItem { + /// The crate's name, *not* the name it's imported as. + src: Option, + }, + ImportItem(Import), + StructItem(Struct), + UnionItem(Union), + EnumItem(Enum), + FunctionItem(Box), + ModuleItem(Module), + TypedefItem(Box), + OpaqueTyItem(OpaqueTy), + StaticItem(Static), + ConstantItem(Constant), + TraitItem(Trait), + TraitAliasItem(TraitAlias), + ImplItem(Box), + /// A required method in a trait declaration meaning it's only a function signature. + TyMethodItem(Box), + /// A method in a trait impl or a provided method in a trait declaration. + /// + /// Compared to [TyMethodItem], it also contains a method body. + MethodItem(Box, Option), + StructFieldItem(Type), + VariantItem(Variant), + /// `fn`s from an extern block + ForeignFunctionItem(Box), + /// `static`s from an extern block + ForeignStaticItem(Static), + /// `type`s from an extern block + ForeignTypeItem, + MacroItem(Macro), + ProcMacroItem(ProcMacro), + PrimitiveItem(PrimitiveType), + /// A required associated constant in a trait declaration. + TyAssocConstItem(Type), + /// An associated associated constant in a trait impl or a provided one in a trait declaration. + AssocConstItem(Type, ConstantKind), + /// A required associated type in a trait declaration. + /// + /// The bounds may be non-empty if there is a `where` clause. + TyAssocTypeItem(Box, Vec), + /// An associated type in a trait impl or a provided one in a trait declaration. + AssocTypeItem(Box, Vec), + /// An item that has been stripped by a rustdoc pass + StrippedItem(Box), + KeywordItem, +} + +impl ItemKind { + /// Some items contain others such as structs (for their fields) and Enums + /// (for their variants). This method returns those contained items. + pub(crate) fn inner_items(&self) -> impl Iterator { + match self { + StructItem(s) => s.fields.iter(), + UnionItem(u) => u.fields.iter(), + VariantItem(Variant::Struct(v)) => v.fields.iter(), + VariantItem(Variant::Tuple(v)) => v.iter(), + EnumItem(e) => e.variants.iter(), + TraitItem(t) => t.items.iter(), + ImplItem(i) => i.items.iter(), + ModuleItem(m) => m.items.iter(), + ExternCrateItem { .. } + | ImportItem(_) + | FunctionItem(_) + | TypedefItem(_) + | OpaqueTyItem(_) + | StaticItem(_) + | ConstantItem(_) + | TraitAliasItem(_) + | TyMethodItem(_) + | MethodItem(_, _) + | StructFieldItem(_) + | VariantItem(_) + | ForeignFunctionItem(_) + | ForeignStaticItem(_) + | ForeignTypeItem + | MacroItem(_) + | ProcMacroItem(_) + | PrimitiveItem(_) + | TyAssocConstItem(_) + | AssocConstItem(_, _) + | TyAssocTypeItem(..) + | AssocTypeItem(..) + | StrippedItem(_) + | KeywordItem => [].iter(), + } + } +} + +#[derive(Clone, Debug)] +pub(crate) struct Module { + pub(crate) items: Vec, + pub(crate) span: Span, +} + +pub(crate) trait AttributesExt { + type AttributeIterator<'a>: Iterator + where + Self: 'a; + + fn lists<'a>(&'a self, name: Symbol) -> Self::AttributeIterator<'a>; + + fn span(&self) -> Option; + + fn inner_docs(&self) -> bool; + + fn other_attrs(&self) -> Vec; + + fn cfg(&self, tcx: TyCtxt<'_>, hidden_cfg: &FxHashSet) -> Option>; +} + +impl AttributesExt for [ast::Attribute] { + type AttributeIterator<'a> = impl Iterator + 'a; + + fn lists<'a>(&'a self, name: Symbol) -> Self::AttributeIterator<'a> { + self.iter() + .filter(move |attr| attr.has_name(name)) + .filter_map(ast::Attribute::meta_item_list) + .flatten() + } + + /// Return the span of the first doc-comment, if it exists. + fn span(&self) -> Option { + self.iter().find(|attr| attr.doc_str().is_some()).map(|attr| attr.span) + } + + /// Returns whether the first doc-comment is an inner attribute. + /// + //// If there are no doc-comments, return true. + /// FIXME(#78591): Support both inner and outer attributes on the same item. + fn inner_docs(&self) -> bool { + self.iter().find(|a| a.doc_str().is_some()).map_or(true, |a| a.style == AttrStyle::Inner) + } + + fn other_attrs(&self) -> Vec { + self.iter().filter(|attr| attr.doc_str().is_none()).cloned().collect() + } + + fn cfg(&self, tcx: TyCtxt<'_>, hidden_cfg: &FxHashSet) -> Option> { + let sess = tcx.sess; + let doc_cfg_active = tcx.features().doc_cfg; + let doc_auto_cfg_active = tcx.features().doc_auto_cfg; + + fn single(it: T) -> Option { + let mut iter = it.into_iter(); + let item = iter.next()?; + if iter.next().is_some() { + return None; + } + Some(item) + } + + let mut cfg = if doc_cfg_active || doc_auto_cfg_active { + let mut doc_cfg = self + .iter() + .filter(|attr| attr.has_name(sym::doc)) + .flat_map(|attr| attr.meta_item_list().unwrap_or_default()) + .filter(|attr| attr.has_name(sym::cfg)) + .peekable(); + if doc_cfg.peek().is_some() && doc_cfg_active { + doc_cfg + .filter_map(|attr| Cfg::parse(attr.meta_item()?).ok()) + .fold(Cfg::True, |cfg, new_cfg| cfg & new_cfg) + } else if doc_auto_cfg_active { + self.iter() + .filter(|attr| attr.has_name(sym::cfg)) + .filter_map(|attr| single(attr.meta_item_list()?)) + .filter_map(|attr| { + Cfg::parse_without(attr.meta_item()?, hidden_cfg).ok().flatten() + }) + .fold(Cfg::True, |cfg, new_cfg| cfg & new_cfg) + } else { + Cfg::True + } + } else { + Cfg::True + }; + + for attr in self.iter() { + // #[doc] + if attr.doc_str().is_none() && attr.has_name(sym::doc) { + // #[doc(...)] + if let Some(list) = attr.meta().as_ref().and_then(|mi| mi.meta_item_list()) { + for item in list { + // #[doc(hidden)] + if !item.has_name(sym::cfg) { + continue; + } + // #[doc(cfg(...))] + if let Some(cfg_mi) = item + .meta_item() + .and_then(|item| rustc_expand::config::parse_cfg(item, sess)) + { + match Cfg::parse(cfg_mi) { + Ok(new_cfg) => cfg &= new_cfg, + Err(e) => { + sess.span_err(e.span, e.msg); + } + } + } + } + } + } + } + + // treat #[target_feature(enable = "feat")] attributes as if they were + // #[doc(cfg(target_feature = "feat"))] attributes as well + for attr in self.lists(sym::target_feature) { + if attr.has_name(sym::enable) { + if let Some(feat) = attr.value_str() { + let meta = attr::mk_name_value_item_str( + Ident::with_dummy_span(sym::target_feature), + feat, + DUMMY_SP, + ); + if let Ok(feat_cfg) = Cfg::parse(&meta) { + cfg &= feat_cfg; + } + } + } + } + + if cfg == Cfg::True { None } else { Some(Arc::new(cfg)) } + } +} + +pub(crate) trait NestedAttributesExt { + /// Returns `true` if the attribute list contains a specific `word` + fn has_word(self, word: Symbol) -> bool + where + Self: std::marker::Sized, + { + ::get_word_attr(self, word).is_some() + } + + /// Returns `Some(attr)` if the attribute list contains 'attr' + /// corresponding to a specific `word` + fn get_word_attr(self, word: Symbol) -> Option; +} + +impl> NestedAttributesExt for I { + fn get_word_attr(mut self, word: Symbol) -> Option { + self.find(|attr| attr.is_word() && attr.has_name(word)) + } +} + +/// A portion of documentation, extracted from a `#[doc]` attribute. +/// +/// Each variant contains the line number within the complete doc-comment where the fragment +/// starts, as well as the Span where the corresponding doc comment or attribute is located. +/// +/// Included files are kept separate from inline doc comments so that proper line-number +/// information can be given when a doctest fails. Sugared doc comments and "raw" doc comments are +/// kept separate because of issue #42760. +#[derive(Clone, PartialEq, Eq, Debug)] +pub(crate) struct DocFragment { + pub(crate) span: rustc_span::Span, + /// The module this doc-comment came from. + /// + /// This allows distinguishing between the original documentation and a pub re-export. + /// If it is `None`, the item was not re-exported. + pub(crate) parent_module: Option, + pub(crate) doc: Symbol, + pub(crate) kind: DocFragmentKind, + pub(crate) indent: usize, +} + +#[derive(Clone, Copy, PartialEq, Eq, Debug)] +pub(crate) enum DocFragmentKind { + /// A doc fragment created from a `///` or `//!` doc comment. + SugaredDoc, + /// A doc fragment created from a "raw" `#[doc=""]` attribute. + RawDoc, +} + +/// The goal of this function is to apply the `DocFragment` transformation that is required when +/// transforming into the final Markdown, which is applying the computed indent to each line in +/// each doc fragment (a `DocFragment` can contain multiple lines in case of `#[doc = ""]`). +/// +/// Note: remove the trailing newline where appropriate +fn add_doc_fragment(out: &mut String, frag: &DocFragment) { + let s = frag.doc.as_str(); + let mut iter = s.lines(); + if s.is_empty() { + out.push('\n'); + return; + } + while let Some(line) = iter.next() { + if line.chars().any(|c| !c.is_whitespace()) { + assert!(line.len() >= frag.indent); + out.push_str(&line[frag.indent..]); + } else { + out.push_str(line); + } + out.push('\n'); + } +} + +/// Collapse a collection of [`DocFragment`]s into one string, +/// handling indentation and newlines as needed. +pub(crate) fn collapse_doc_fragments(doc_strings: &[DocFragment]) -> String { + let mut acc = String::new(); + for frag in doc_strings { + add_doc_fragment(&mut acc, frag); + } + acc.pop(); + acc +} + +/// Removes excess indentation on comments in order for the Markdown +/// to be parsed correctly. This is necessary because the convention for +/// writing documentation is to provide a space between the /// or //! marker +/// and the doc text, but Markdown is whitespace-sensitive. For example, +/// a block of text with four-space indentation is parsed as a code block, +/// so if we didn't unindent comments, these list items +/// +/// /// A list: +/// /// +/// /// - Foo +/// /// - Bar +/// +/// would be parsed as if they were in a code block, which is likely not what the user intended. +fn unindent_doc_fragments(docs: &mut Vec) { + // `add` is used in case the most common sugared doc syntax is used ("/// "). The other + // fragments kind's lines are never starting with a whitespace unless they are using some + // markdown formatting requiring it. Therefore, if the doc block have a mix between the two, + // we need to take into account the fact that the minimum indent minus one (to take this + // whitespace into account). + // + // For example: + // + // /// hello! + // #[doc = "another"] + // + // In this case, you want "hello! another" and not "hello! another". + let add = if docs.windows(2).any(|arr| arr[0].kind != arr[1].kind) + && docs.iter().any(|d| d.kind == DocFragmentKind::SugaredDoc) + { + // In case we have a mix of sugared doc comments and "raw" ones, we want the sugared one to + // "decide" how much the minimum indent will be. + 1 + } else { + 0 + }; + + // `min_indent` is used to know how much whitespaces from the start of each lines must be + // removed. Example: + // + // /// hello! + // #[doc = "another"] + // + // In here, the `min_indent` is 1 (because non-sugared fragment are always counted with minimum + // 1 whitespace), meaning that "hello!" will be considered a codeblock because it starts with 4 + // (5 - 1) whitespaces. + let Some(min_indent) = docs + .iter() + .map(|fragment| { + fragment.doc.as_str().lines().fold(usize::MAX, |min_indent, line| { + if line.chars().all(|c| c.is_whitespace()) { + min_indent + } else { + // Compare against either space or tab, ignoring whether they are + // mixed or not. + let whitespace = line.chars().take_while(|c| *c == ' ' || *c == '\t').count(); + cmp::min(min_indent, whitespace) + + if fragment.kind == DocFragmentKind::SugaredDoc { 0 } else { add } + } + }) + }) + .min() + else { + return; + }; + + for fragment in docs { + if fragment.doc == kw::Empty { + continue; + } + + let min_indent = if fragment.kind != DocFragmentKind::SugaredDoc && min_indent > 0 { + min_indent - add + } else { + min_indent + }; + + fragment.indent = min_indent; + } +} + +/// A link that has not yet been rendered. +/// +/// This link will be turned into a rendered link by [`Item::links`]. +#[derive(Clone, Debug, PartialEq, Eq)] +pub(crate) struct ItemLink { + /// The original link written in the markdown + pub(crate) link: String, + /// The link text displayed in the HTML. + /// + /// This may not be the same as `link` if there was a disambiguator + /// in an intra-doc link (e.g. \[`fn@f`\]) + pub(crate) link_text: String, + pub(crate) did: DefId, + /// The url fragment to append to the link + pub(crate) fragment: Option, +} + +pub struct RenderedLink { + /// The text the link was original written as. + /// + /// This could potentially include disambiguators and backticks. + pub(crate) original_text: String, + /// The text to display in the HTML + pub(crate) new_text: String, + /// The URL to put in the `href` + pub(crate) href: String, +} + +/// The attributes on an [`Item`], including attributes like `#[derive(...)]` and `#[inline]`, +/// as well as doc comments. +#[derive(Clone, Debug, Default)] +pub(crate) struct Attributes { + pub(crate) doc_strings: Vec, + pub(crate) other_attrs: Vec, +} + +impl Attributes { + pub(crate) fn lists(&self, name: Symbol) -> impl Iterator + '_ { + self.other_attrs.lists(name) + } + + pub(crate) fn has_doc_flag(&self, flag: Symbol) -> bool { + for attr in &self.other_attrs { + if !attr.has_name(sym::doc) { + continue; + } + + if let Some(items) = attr.meta_item_list() { + if items.iter().filter_map(|i| i.meta_item()).any(|it| it.has_name(flag)) { + return true; + } + } + } + + false + } + + pub(crate) fn from_ast(attrs: &[ast::Attribute]) -> Attributes { + Attributes::from_ast_iter(attrs.iter().map(|attr| (attr, None)), false) + } + + pub(crate) fn from_ast_with_additional( + attrs: &[ast::Attribute], + (additional_attrs, def_id): (&[ast::Attribute], DefId), + ) -> Attributes { + // Additional documentation should be shown before the original documentation. + let attrs1 = additional_attrs.iter().map(|attr| (attr, Some(def_id))); + let attrs2 = attrs.iter().map(|attr| (attr, None)); + Attributes::from_ast_iter(attrs1.chain(attrs2), false) + } + + pub(crate) fn from_ast_iter<'a>( + attrs: impl Iterator)>, + doc_only: bool, + ) -> Attributes { + let mut doc_strings = Vec::new(); + let mut other_attrs = Vec::new(); + for (attr, parent_module) in attrs { + if let Some((doc_str, comment_kind)) = attr.doc_str_and_comment_kind() { + trace!("got doc_str={doc_str:?}"); + let doc = beautify_doc_string(doc_str, comment_kind); + let kind = if attr.is_doc_comment() { + DocFragmentKind::SugaredDoc + } else { + DocFragmentKind::RawDoc + }; + let fragment = DocFragment { span: attr.span, doc, kind, parent_module, indent: 0 }; + doc_strings.push(fragment); + } else if !doc_only { + other_attrs.push(attr.clone()); + } + } + + unindent_doc_fragments(&mut doc_strings); + + Attributes { doc_strings, other_attrs } + } + + /// Finds the `doc` attribute as a NameValue and returns the corresponding + /// value found. + pub(crate) fn doc_value(&self) -> Option { + let mut iter = self.doc_strings.iter(); + + let ori = iter.next()?; + let mut out = String::new(); + add_doc_fragment(&mut out, ori); + for new_frag in iter { + add_doc_fragment(&mut out, new_frag); + } + out.pop(); + if out.is_empty() { None } else { Some(out) } + } + + /// Return the doc-comments on this item, grouped by the module they came from. + /// The module can be different if this is a re-export with added documentation. + /// + /// The last newline is not trimmed so the produced strings are reusable between + /// early and late doc link resolution regardless of their position. + pub(crate) fn prepare_to_doc_link_resolution(&self) -> FxHashMap, String> { + let mut res = FxHashMap::default(); + for fragment in &self.doc_strings { + let out_str = res.entry(fragment.parent_module).or_default(); + add_doc_fragment(out_str, fragment); + } + res + } + + /// Finds all `doc` attributes as NameValues and returns their corresponding values, joined + /// with newlines. + pub(crate) fn collapsed_doc_value(&self) -> Option { + if self.doc_strings.is_empty() { + None + } else { + Some(collapse_doc_fragments(&self.doc_strings)) + } + } + + pub(crate) fn get_doc_aliases(&self) -> Box<[Symbol]> { + let mut aliases = FxHashSet::default(); + + for attr in self.other_attrs.lists(sym::doc).filter(|a| a.has_name(sym::alias)) { + if let Some(values) = attr.meta_item_list() { + for l in values { + match l.literal().unwrap().kind { + ast::LitKind::Str(s, _) => { + aliases.insert(s); + } + _ => unreachable!(), + } + } + } else { + aliases.insert(attr.value_str().unwrap()); + } + } + aliases.into_iter().collect::>().into() + } +} + +impl PartialEq for Attributes { + fn eq(&self, rhs: &Self) -> bool { + self.doc_strings == rhs.doc_strings + && self + .other_attrs + .iter() + .map(|attr| attr.id) + .eq(rhs.other_attrs.iter().map(|attr| attr.id)) + } +} + +impl Eq for Attributes {} + +#[derive(Clone, PartialEq, Eq, Debug, Hash)] +pub(crate) enum GenericBound { + TraitBound(PolyTrait, hir::TraitBoundModifier), + Outlives(Lifetime), +} + +impl GenericBound { + pub(crate) fn maybe_sized(cx: &mut DocContext<'_>) -> GenericBound { + let did = cx.tcx.require_lang_item(LangItem::Sized, None); + let empty = cx.tcx.intern_substs(&[]); + let path = external_path(cx, did, false, vec![], empty); + inline::record_extern_fqn(cx, did, ItemType::Trait); + GenericBound::TraitBound( + PolyTrait { trait_: path, generic_params: Vec::new() }, + hir::TraitBoundModifier::Maybe, + ) + } + + pub(crate) fn is_sized_bound(&self, cx: &DocContext<'_>) -> bool { + use rustc_hir::TraitBoundModifier as TBM; + if let GenericBound::TraitBound(PolyTrait { ref trait_, .. }, TBM::None) = *self { + if Some(trait_.def_id()) == cx.tcx.lang_items().sized_trait() { + return true; + } + } + false + } + + pub(crate) fn get_poly_trait(&self) -> Option { + if let GenericBound::TraitBound(ref p, _) = *self { + return Some(p.clone()); + } + None + } + + pub(crate) fn get_trait_path(&self) -> Option { + if let GenericBound::TraitBound(PolyTrait { ref trait_, .. }, _) = *self { + Some(trait_.clone()) + } else { + None + } + } +} + +#[derive(Clone, PartialEq, Eq, Debug, Hash)] +pub(crate) struct Lifetime(pub Symbol); + +impl Lifetime { + pub(crate) fn statik() -> Lifetime { + Lifetime(kw::StaticLifetime) + } + + pub(crate) fn elided() -> Lifetime { + Lifetime(kw::UnderscoreLifetime) + } +} + +#[derive(Clone, Debug)] +pub(crate) enum WherePredicate { + BoundPredicate { ty: Type, bounds: Vec, bound_params: Vec }, + RegionPredicate { lifetime: Lifetime, bounds: Vec }, + EqPredicate { lhs: Type, rhs: Term }, +} + +impl WherePredicate { + pub(crate) fn get_bounds(&self) -> Option<&[GenericBound]> { + match *self { + WherePredicate::BoundPredicate { ref bounds, .. } => Some(bounds), + WherePredicate::RegionPredicate { ref bounds, .. } => Some(bounds), + _ => None, + } + } +} + +#[derive(Clone, PartialEq, Eq, Debug, Hash)] +pub(crate) enum GenericParamDefKind { + Lifetime { outlives: Vec }, + Type { did: DefId, bounds: Vec, default: Option>, synthetic: bool }, + Const { did: DefId, ty: Box, default: Option> }, +} + +impl GenericParamDefKind { + pub(crate) fn is_type(&self) -> bool { + matches!(self, GenericParamDefKind::Type { .. }) + } +} + +#[derive(Clone, PartialEq, Eq, Debug, Hash)] +pub(crate) struct GenericParamDef { + pub(crate) name: Symbol, + pub(crate) kind: GenericParamDefKind, +} + +impl GenericParamDef { + pub(crate) fn is_synthetic_type_param(&self) -> bool { + match self.kind { + GenericParamDefKind::Lifetime { .. } | GenericParamDefKind::Const { .. } => false, + GenericParamDefKind::Type { synthetic, .. } => synthetic, + } + } + + pub(crate) fn is_type(&self) -> bool { + self.kind.is_type() + } + + pub(crate) fn get_bounds(&self) -> Option<&[GenericBound]> { + match self.kind { + GenericParamDefKind::Type { ref bounds, .. } => Some(bounds), + _ => None, + } + } +} + +// maybe use a Generic enum and use Vec? +#[derive(Clone, Debug, Default)] +pub(crate) struct Generics { + pub(crate) params: Vec, + pub(crate) where_predicates: Vec, +} + +impl Generics { + pub(crate) fn is_empty(&self) -> bool { + self.params.is_empty() && self.where_predicates.is_empty() + } +} + +#[derive(Clone, Debug)] +pub(crate) struct Function { + pub(crate) decl: FnDecl, + pub(crate) generics: Generics, +} + +#[derive(Clone, PartialEq, Eq, Debug, Hash)] +pub(crate) struct FnDecl { + pub(crate) inputs: Arguments, + pub(crate) output: FnRetTy, + pub(crate) c_variadic: bool, +} + +impl FnDecl { + pub(crate) fn self_type(&self) -> Option { + self.inputs.values.get(0).and_then(|v| v.to_self()) + } + + /// Returns the sugared return type for an async function. + /// + /// For example, if the return type is `impl std::future::Future`, this function + /// will return `i32`. + /// + /// # Panics + /// + /// This function will panic if the return type does not match the expected sugaring for async + /// functions. + pub(crate) fn sugared_async_return_type(&self) -> FnRetTy { + match &self.output { + FnRetTy::Return(Type::ImplTrait(bounds)) => match &bounds[0] { + GenericBound::TraitBound(PolyTrait { trait_, .. }, ..) => { + let bindings = trait_.bindings().unwrap(); + let ret_ty = bindings[0].term(); + let ty = ret_ty.ty().expect("Unexpected constant return term"); + FnRetTy::Return(ty.clone()) + } + _ => panic!("unexpected desugaring of async function"), + }, + _ => panic!("unexpected desugaring of async function"), + } + } +} + +#[derive(Clone, PartialEq, Eq, Debug, Hash)] +pub(crate) struct Arguments { + pub(crate) values: Vec, +} + +#[derive(Clone, PartialEq, Eq, Debug, Hash)] +pub(crate) struct Argument { + pub(crate) type_: Type, + pub(crate) name: Symbol, + /// This field is used to represent "const" arguments from the `rustc_legacy_const_generics` + /// feature. More information in . + pub(crate) is_const: bool, +} + +#[derive(Clone, PartialEq, Debug)] +pub(crate) enum SelfTy { + SelfValue, + SelfBorrowed(Option, Mutability), + SelfExplicit(Type), +} + +impl Argument { + pub(crate) fn to_self(&self) -> Option { + if self.name != kw::SelfLower { + return None; + } + if self.type_.is_self_type() { + return Some(SelfValue); + } + match self.type_ { + BorrowedRef { ref lifetime, mutability, ref type_ } if type_.is_self_type() => { + Some(SelfBorrowed(lifetime.clone(), mutability)) + } + _ => Some(SelfExplicit(self.type_.clone())), + } + } +} + +#[derive(Clone, PartialEq, Eq, Debug, Hash)] +pub(crate) enum FnRetTy { + Return(Type), + DefaultReturn, +} + +impl FnRetTy { + pub(crate) fn as_return(&self) -> Option<&Type> { + match self { + Return(ret) => Some(ret), + DefaultReturn => None, + } + } +} + +#[derive(Clone, Debug)] +pub(crate) struct Trait { + pub(crate) def_id: DefId, + pub(crate) items: Vec, + pub(crate) generics: Generics, + pub(crate) bounds: Vec, +} + +impl Trait { + pub(crate) fn is_auto(&self, tcx: TyCtxt<'_>) -> bool { + tcx.trait_is_auto(self.def_id) + } + pub(crate) fn unsafety(&self, tcx: TyCtxt<'_>) -> hir::Unsafety { + tcx.trait_def(self.def_id).unsafety + } +} + +#[derive(Clone, Debug)] +pub(crate) struct TraitAlias { + pub(crate) generics: Generics, + pub(crate) bounds: Vec, +} + +/// A trait reference, which may have higher ranked lifetimes. +#[derive(Clone, PartialEq, Eq, Debug, Hash)] +pub(crate) struct PolyTrait { + pub(crate) trait_: Path, + pub(crate) generic_params: Vec, +} + +/// Rustdoc's representation of types, mostly based on the [`hir::Ty`]. +#[derive(Clone, PartialEq, Eq, Debug, Hash)] +pub(crate) enum Type { + /// A named type, which could be a trait. + /// + /// This is mostly Rustdoc's version of [`hir::Path`]. + /// It has to be different because Rustdoc's [`PathSegment`] can contain cleaned generics. + Path { path: Path }, + /// A `dyn Trait` object: `dyn for<'a> Trait<'a> + Send + 'static` + DynTrait(Vec, Option), + /// A type parameter. + Generic(Symbol), + /// A primitive (aka, builtin) type. + Primitive(PrimitiveType), + /// A function pointer: `extern "ABI" fn(...) -> ...` + BareFunction(Box), + /// A tuple type: `(i32, &str)`. + Tuple(Vec), + /// A slice type (does *not* include the `&`): `[i32]` + Slice(Box), + /// An array type. + /// + /// The `String` field is a stringified version of the array's length parameter. + Array(Box, String), + /// A raw pointer type: `*const i32`, `*mut i32` + RawPointer(Mutability, Box), + /// A reference type: `&i32`, `&'a mut Foo` + BorrowedRef { lifetime: Option, mutability: Mutability, type_: Box }, + + /// A qualified path to an associated item: `::Name` + QPath { + assoc: Box, + self_type: Box, + /// FIXME: compute this field on demand. + should_show_cast: bool, + trait_: Path, + }, + + /// A type that is inferred: `_` + Infer, + + /// An `impl Trait`: `impl TraitA + TraitB + ...` + ImplTrait(Vec), +} + +impl Type { + /// When comparing types for equality, it can help to ignore `&` wrapping. + pub(crate) fn without_borrowed_ref(&self) -> &Type { + let mut result = self; + while let Type::BorrowedRef { type_, .. } = result { + result = &*type_; + } + result + } + + /// Check if two types are "potentially the same". + /// This is different from `Eq`, because it knows that things like + /// `Placeholder` are possible matches for everything. + pub(crate) fn is_same(&self, other: &Self, cache: &Cache) -> bool { + match (self, other) { + // Recursive cases. + (Type::Tuple(a), Type::Tuple(b)) => { + a.len() == b.len() && a.iter().zip(b).all(|(a, b)| a.is_same(b, cache)) + } + (Type::Slice(a), Type::Slice(b)) => a.is_same(b, cache), + (Type::Array(a, al), Type::Array(b, bl)) => al == bl && a.is_same(b, cache), + (Type::RawPointer(mutability, type_), Type::RawPointer(b_mutability, b_type_)) => { + mutability == b_mutability && type_.is_same(b_type_, cache) + } + ( + Type::BorrowedRef { mutability, type_, .. }, + Type::BorrowedRef { mutability: b_mutability, type_: b_type_, .. }, + ) => mutability == b_mutability && type_.is_same(b_type_, cache), + // Placeholders and generics are equal to all other types. + (Type::Infer, _) | (_, Type::Infer) => true, + (Type::Generic(_), _) | (_, Type::Generic(_)) => true, + // Other cases, such as primitives, just use recursion. + (a, b) => a + .def_id(cache) + .and_then(|a| Some((a, b.def_id(cache)?))) + .map(|(a, b)| a == b) + .unwrap_or(false), + } + } + + pub(crate) fn primitive_type(&self) -> Option { + match *self { + Primitive(p) | BorrowedRef { type_: box Primitive(p), .. } => Some(p), + Slice(..) | BorrowedRef { type_: box Slice(..), .. } => Some(PrimitiveType::Slice), + Array(..) | BorrowedRef { type_: box Array(..), .. } => Some(PrimitiveType::Array), + Tuple(ref tys) => { + if tys.is_empty() { + Some(PrimitiveType::Unit) + } else { + Some(PrimitiveType::Tuple) + } + } + RawPointer(..) => Some(PrimitiveType::RawPointer), + BareFunction(..) => Some(PrimitiveType::Fn), + _ => None, + } + } + + /// Checks if this is a `T::Name` path for an associated type. + pub(crate) fn is_assoc_ty(&self) -> bool { + match self { + Type::Path { path, .. } => path.is_assoc_ty(), + _ => false, + } + } + + pub(crate) fn is_self_type(&self) -> bool { + match *self { + Generic(name) => name == kw::SelfUpper, + _ => false, + } + } + + pub(crate) fn generics(&self) -> Option> { + match self { + Type::Path { path, .. } => path.generics(), + _ => None, + } + } + + pub(crate) fn is_full_generic(&self) -> bool { + matches!(self, Type::Generic(_)) + } + + pub(crate) fn is_impl_trait(&self) -> bool { + matches!(self, Type::ImplTrait(_)) + } + + pub(crate) fn projection(&self) -> Option<(&Type, DefId, PathSegment)> { + if let QPath { self_type, trait_, assoc, .. } = self { + Some((self_type, trait_.def_id(), *assoc.clone())) + } else { + None + } + } + + fn inner_def_id(&self, cache: Option<&Cache>) -> Option { + let t: PrimitiveType = match *self { + Type::Path { ref path } => return Some(path.def_id()), + DynTrait(ref bounds, _) => return Some(bounds[0].trait_.def_id()), + Primitive(p) => return cache.and_then(|c| c.primitive_locations.get(&p).cloned()), + BorrowedRef { type_: box Generic(..), .. } => PrimitiveType::Reference, + BorrowedRef { ref type_, .. } => return type_.inner_def_id(cache), + Tuple(ref tys) => { + if tys.is_empty() { + PrimitiveType::Unit + } else { + PrimitiveType::Tuple + } + } + BareFunction(..) => PrimitiveType::Fn, + Slice(..) => PrimitiveType::Slice, + Array(..) => PrimitiveType::Array, + RawPointer(..) => PrimitiveType::RawPointer, + QPath { ref self_type, .. } => return self_type.inner_def_id(cache), + Generic(_) | Infer | ImplTrait(_) => return None, + }; + cache.and_then(|c| Primitive(t).def_id(c)) + } + + /// Use this method to get the [DefId] of a [clean] AST node, including [PrimitiveType]s. + /// + /// [clean]: crate::clean + pub(crate) fn def_id(&self, cache: &Cache) -> Option { + self.inner_def_id(Some(cache)) + } +} + +/// A primitive (aka, builtin) type. +/// +/// This represents things like `i32`, `str`, etc. +/// +/// N.B. This has to be different from [`hir::PrimTy`] because it also includes types that aren't +/// paths, like [`Self::Unit`]. +#[derive(Clone, PartialEq, Eq, Hash, Copy, Debug)] +pub(crate) enum PrimitiveType { + Isize, + I8, + I16, + I32, + I64, + I128, + Usize, + U8, + U16, + U32, + U64, + U128, + F32, + F64, + Char, + Bool, + Str, + Slice, + Array, + Tuple, + Unit, + RawPointer, + Reference, + Fn, + Never, +} + +type SimplifiedTypes = FxHashMap>; +impl PrimitiveType { + pub(crate) fn from_hir(prim: hir::PrimTy) -> PrimitiveType { + use ast::{FloatTy, IntTy, UintTy}; + match prim { + hir::PrimTy::Int(IntTy::Isize) => PrimitiveType::Isize, + hir::PrimTy::Int(IntTy::I8) => PrimitiveType::I8, + hir::PrimTy::Int(IntTy::I16) => PrimitiveType::I16, + hir::PrimTy::Int(IntTy::I32) => PrimitiveType::I32, + hir::PrimTy::Int(IntTy::I64) => PrimitiveType::I64, + hir::PrimTy::Int(IntTy::I128) => PrimitiveType::I128, + hir::PrimTy::Uint(UintTy::Usize) => PrimitiveType::Usize, + hir::PrimTy::Uint(UintTy::U8) => PrimitiveType::U8, + hir::PrimTy::Uint(UintTy::U16) => PrimitiveType::U16, + hir::PrimTy::Uint(UintTy::U32) => PrimitiveType::U32, + hir::PrimTy::Uint(UintTy::U64) => PrimitiveType::U64, + hir::PrimTy::Uint(UintTy::U128) => PrimitiveType::U128, + hir::PrimTy::Float(FloatTy::F32) => PrimitiveType::F32, + hir::PrimTy::Float(FloatTy::F64) => PrimitiveType::F64, + hir::PrimTy::Str => PrimitiveType::Str, + hir::PrimTy::Bool => PrimitiveType::Bool, + hir::PrimTy::Char => PrimitiveType::Char, + } + } + + pub(crate) fn from_symbol(s: Symbol) -> Option { + match s { + sym::isize => Some(PrimitiveType::Isize), + sym::i8 => Some(PrimitiveType::I8), + sym::i16 => Some(PrimitiveType::I16), + sym::i32 => Some(PrimitiveType::I32), + sym::i64 => Some(PrimitiveType::I64), + sym::i128 => Some(PrimitiveType::I128), + sym::usize => Some(PrimitiveType::Usize), + sym::u8 => Some(PrimitiveType::U8), + sym::u16 => Some(PrimitiveType::U16), + sym::u32 => Some(PrimitiveType::U32), + sym::u64 => Some(PrimitiveType::U64), + sym::u128 => Some(PrimitiveType::U128), + sym::bool => Some(PrimitiveType::Bool), + sym::char => Some(PrimitiveType::Char), + sym::str => Some(PrimitiveType::Str), + sym::f32 => Some(PrimitiveType::F32), + sym::f64 => Some(PrimitiveType::F64), + sym::array => Some(PrimitiveType::Array), + sym::slice => Some(PrimitiveType::Slice), + sym::tuple => Some(PrimitiveType::Tuple), + sym::unit => Some(PrimitiveType::Unit), + sym::pointer => Some(PrimitiveType::RawPointer), + sym::reference => Some(PrimitiveType::Reference), + kw::Fn => Some(PrimitiveType::Fn), + sym::never => Some(PrimitiveType::Never), + _ => None, + } + } + + pub(crate) fn simplified_types() -> &'static SimplifiedTypes { + use ty::fast_reject::SimplifiedTypeGen::*; + use ty::{FloatTy, IntTy, UintTy}; + use PrimitiveType::*; + static CELL: OnceCell = OnceCell::new(); + + let single = |x| iter::once(x).collect(); + CELL.get_or_init(move || { + map! { + Isize => single(IntSimplifiedType(IntTy::Isize)), + I8 => single(IntSimplifiedType(IntTy::I8)), + I16 => single(IntSimplifiedType(IntTy::I16)), + I32 => single(IntSimplifiedType(IntTy::I32)), + I64 => single(IntSimplifiedType(IntTy::I64)), + I128 => single(IntSimplifiedType(IntTy::I128)), + Usize => single(UintSimplifiedType(UintTy::Usize)), + U8 => single(UintSimplifiedType(UintTy::U8)), + U16 => single(UintSimplifiedType(UintTy::U16)), + U32 => single(UintSimplifiedType(UintTy::U32)), + U64 => single(UintSimplifiedType(UintTy::U64)), + U128 => single(UintSimplifiedType(UintTy::U128)), + F32 => single(FloatSimplifiedType(FloatTy::F32)), + F64 => single(FloatSimplifiedType(FloatTy::F64)), + Str => single(StrSimplifiedType), + Bool => single(BoolSimplifiedType), + Char => single(CharSimplifiedType), + Array => single(ArraySimplifiedType), + Slice => single(SliceSimplifiedType), + // FIXME: If we ever add an inherent impl for tuples + // with different lengths, they won't show in rustdoc. + // + // Either manually update this arrayvec at this point + // or start with a more complex refactoring. + Tuple => [TupleSimplifiedType(1), TupleSimplifiedType(2), TupleSimplifiedType(3)].into(), + Unit => single(TupleSimplifiedType(0)), + RawPointer => [PtrSimplifiedType(Mutability::Not), PtrSimplifiedType(Mutability::Mut)].into_iter().collect(), + Reference => [RefSimplifiedType(Mutability::Not), RefSimplifiedType(Mutability::Mut)].into_iter().collect(), + // FIXME: This will be wrong if we ever add inherent impls + // for function pointers. + Fn => single(FunctionSimplifiedType(1)), + Never => single(NeverSimplifiedType), + } + }) + } + + pub(crate) fn impls<'tcx>(&self, tcx: TyCtxt<'tcx>) -> impl Iterator + 'tcx { + Self::simplified_types() + .get(self) + .into_iter() + .flatten() + .flat_map(move |&simp| tcx.incoherent_impls(simp)) + .copied() + } + + pub(crate) fn all_impls(tcx: TyCtxt<'_>) -> impl Iterator + '_ { + Self::simplified_types() + .values() + .flatten() + .flat_map(move |&simp| tcx.incoherent_impls(simp)) + .copied() + } + + pub(crate) fn as_sym(&self) -> Symbol { + use PrimitiveType::*; + match self { + Isize => sym::isize, + I8 => sym::i8, + I16 => sym::i16, + I32 => sym::i32, + I64 => sym::i64, + I128 => sym::i128, + Usize => sym::usize, + U8 => sym::u8, + U16 => sym::u16, + U32 => sym::u32, + U64 => sym::u64, + U128 => sym::u128, + F32 => sym::f32, + F64 => sym::f64, + Str => sym::str, + Bool => sym::bool, + Char => sym::char, + Array => sym::array, + Slice => sym::slice, + Tuple => sym::tuple, + Unit => sym::unit, + RawPointer => sym::pointer, + Reference => sym::reference, + Fn => kw::Fn, + Never => sym::never, + } + } + + /// Returns the DefId of the module with `doc(primitive)` for this primitive type. + /// Panics if there is no such module. + /// + /// This gives precedence to primitives defined in the current crate, and deprioritizes primitives defined in `core`, + /// but otherwise, if multiple crates define the same primitive, there is no guarantee of which will be picked. + /// In particular, if a crate depends on both `std` and another crate that also defines `doc(primitive)`, then + /// it's entirely random whether `std` or the other crate is picked. (no_std crates are usually fine unless multiple dependencies define a primitive.) + pub(crate) fn primitive_locations(tcx: TyCtxt<'_>) -> &FxHashMap { + static PRIMITIVE_LOCATIONS: OnceCell> = OnceCell::new(); + PRIMITIVE_LOCATIONS.get_or_init(|| { + let mut primitive_locations = FxHashMap::default(); + // NOTE: technically this misses crates that are only passed with `--extern` and not loaded when checking the crate. + // This is a degenerate case that I don't plan to support. + for &crate_num in tcx.crates(()) { + let e = ExternalCrate { crate_num }; + let crate_name = e.name(tcx); + debug!(?crate_num, ?crate_name); + for &(def_id, prim) in &e.primitives(tcx) { + // HACK: try to link to std instead where possible + if crate_name == sym::core && primitive_locations.contains_key(&prim) { + continue; + } + primitive_locations.insert(prim, def_id); + } + } + let local_primitives = ExternalCrate { crate_num: LOCAL_CRATE }.primitives(tcx); + for (def_id, prim) in local_primitives { + primitive_locations.insert(prim, def_id); + } + primitive_locations + }) + } +} + +impl From for PrimitiveType { + fn from(int_ty: ast::IntTy) -> PrimitiveType { + match int_ty { + ast::IntTy::Isize => PrimitiveType::Isize, + ast::IntTy::I8 => PrimitiveType::I8, + ast::IntTy::I16 => PrimitiveType::I16, + ast::IntTy::I32 => PrimitiveType::I32, + ast::IntTy::I64 => PrimitiveType::I64, + ast::IntTy::I128 => PrimitiveType::I128, + } + } +} + +impl From for PrimitiveType { + fn from(uint_ty: ast::UintTy) -> PrimitiveType { + match uint_ty { + ast::UintTy::Usize => PrimitiveType::Usize, + ast::UintTy::U8 => PrimitiveType::U8, + ast::UintTy::U16 => PrimitiveType::U16, + ast::UintTy::U32 => PrimitiveType::U32, + ast::UintTy::U64 => PrimitiveType::U64, + ast::UintTy::U128 => PrimitiveType::U128, + } + } +} + +impl From for PrimitiveType { + fn from(float_ty: ast::FloatTy) -> PrimitiveType { + match float_ty { + ast::FloatTy::F32 => PrimitiveType::F32, + ast::FloatTy::F64 => PrimitiveType::F64, + } + } +} + +impl From for PrimitiveType { + fn from(int_ty: ty::IntTy) -> PrimitiveType { + match int_ty { + ty::IntTy::Isize => PrimitiveType::Isize, + ty::IntTy::I8 => PrimitiveType::I8, + ty::IntTy::I16 => PrimitiveType::I16, + ty::IntTy::I32 => PrimitiveType::I32, + ty::IntTy::I64 => PrimitiveType::I64, + ty::IntTy::I128 => PrimitiveType::I128, + } + } +} + +impl From for PrimitiveType { + fn from(uint_ty: ty::UintTy) -> PrimitiveType { + match uint_ty { + ty::UintTy::Usize => PrimitiveType::Usize, + ty::UintTy::U8 => PrimitiveType::U8, + ty::UintTy::U16 => PrimitiveType::U16, + ty::UintTy::U32 => PrimitiveType::U32, + ty::UintTy::U64 => PrimitiveType::U64, + ty::UintTy::U128 => PrimitiveType::U128, + } + } +} + +impl From for PrimitiveType { + fn from(float_ty: ty::FloatTy) -> PrimitiveType { + match float_ty { + ty::FloatTy::F32 => PrimitiveType::F32, + ty::FloatTy::F64 => PrimitiveType::F64, + } + } +} + +impl From for PrimitiveType { + fn from(prim_ty: hir::PrimTy) -> PrimitiveType { + match prim_ty { + hir::PrimTy::Int(int_ty) => int_ty.into(), + hir::PrimTy::Uint(uint_ty) => uint_ty.into(), + hir::PrimTy::Float(float_ty) => float_ty.into(), + hir::PrimTy::Str => PrimitiveType::Str, + hir::PrimTy::Bool => PrimitiveType::Bool, + hir::PrimTy::Char => PrimitiveType::Char, + } + } +} + +#[derive(Copy, Clone, Debug)] +pub(crate) enum Visibility { + /// `pub` + Public, + /// Visibility inherited from parent. + /// + /// For example, this is the visibility of private items and of enum variants. + Inherited, + /// `pub(crate)`, `pub(super)`, or `pub(in path::to::somewhere)` + Restricted(DefId), +} + +impl Visibility { + pub(crate) fn is_public(&self) -> bool { + matches!(self, Visibility::Public) + } +} + +#[derive(Clone, Debug)] +pub(crate) struct Struct { + pub(crate) struct_type: CtorKind, + pub(crate) generics: Generics, + pub(crate) fields: Vec, +} + +impl Struct { + pub(crate) fn has_stripped_entries(&self) -> bool { + self.fields.iter().any(|f| f.is_stripped()) + } +} + +#[derive(Clone, Debug)] +pub(crate) struct Union { + pub(crate) generics: Generics, + pub(crate) fields: Vec, +} + +impl Union { + pub(crate) fn has_stripped_entries(&self) -> bool { + self.fields.iter().any(|f| f.is_stripped()) + } +} + +/// This is a more limited form of the standard Struct, different in that +/// it lacks the things most items have (name, id, parameterization). Found +/// only as a variant in an enum. +#[derive(Clone, Debug)] +pub(crate) struct VariantStruct { + pub(crate) struct_type: CtorKind, + pub(crate) fields: Vec, +} + +impl VariantStruct { + pub(crate) fn has_stripped_entries(&self) -> bool { + self.fields.iter().any(|f| f.is_stripped()) + } +} + +#[derive(Clone, Debug)] +pub(crate) struct Enum { + pub(crate) variants: IndexVec, + pub(crate) generics: Generics, +} + +impl Enum { + pub(crate) fn has_stripped_entries(&self) -> bool { + self.variants.iter().any(|f| f.is_stripped()) + } + + pub(crate) fn variants(&self) -> impl Iterator { + self.variants.iter().filter(|v| !v.is_stripped()) + } +} + +#[derive(Clone, Debug)] +pub(crate) enum Variant { + CLike, + Tuple(Vec), + Struct(VariantStruct), +} + +impl Variant { + pub(crate) fn has_stripped_entries(&self) -> Option { + match *self { + Self::Struct(ref struct_) => Some(struct_.has_stripped_entries()), + Self::CLike | Self::Tuple(_) => None, + } + } +} + +/// Small wrapper around [`rustc_span::Span`] that adds helper methods +/// and enforces calling [`rustc_span::Span::source_callsite()`]. +#[derive(Copy, Clone, Debug)] +pub(crate) struct Span(rustc_span::Span); + +impl Span { + /// Wraps a [`rustc_span::Span`]. In case this span is the result of a macro expansion, the + /// span will be updated to point to the macro invocation instead of the macro definition. + /// + /// (See rust-lang/rust#39726) + pub(crate) fn new(sp: rustc_span::Span) -> Self { + Self(sp.source_callsite()) + } + + pub(crate) fn inner(&self) -> rustc_span::Span { + self.0 + } + + pub(crate) fn dummy() -> Self { + Self(rustc_span::DUMMY_SP) + } + + pub(crate) fn is_dummy(&self) -> bool { + self.0.is_dummy() + } + + pub(crate) fn filename(&self, sess: &Session) -> FileName { + sess.source_map().span_to_filename(self.0) + } + + pub(crate) fn lo(&self, sess: &Session) -> Loc { + sess.source_map().lookup_char_pos(self.0.lo()) + } + + pub(crate) fn hi(&self, sess: &Session) -> Loc { + sess.source_map().lookup_char_pos(self.0.hi()) + } + + pub(crate) fn cnum(&self, sess: &Session) -> CrateNum { + // FIXME: is there a time when the lo and hi crate would be different? + self.lo(sess).file.cnum + } +} + +#[derive(Clone, PartialEq, Eq, Debug, Hash)] +pub(crate) struct Path { + pub(crate) res: Res, + pub(crate) segments: Vec, +} + +impl Path { + pub(crate) fn def_id(&self) -> DefId { + self.res.def_id() + } + + pub(crate) fn last_opt(&self) -> Option { + self.segments.last().map(|s| s.name) + } + + pub(crate) fn last(&self) -> Symbol { + self.last_opt().expect("segments were empty") + } + + pub(crate) fn whole_name(&self) -> String { + self.segments + .iter() + .map(|s| if s.name == kw::PathRoot { "" } else { s.name.as_str() }) + .intersperse("::") + .collect() + } + + /// Checks if this is a `T::Name` path for an associated type. + pub(crate) fn is_assoc_ty(&self) -> bool { + match self.res { + Res::SelfTy { .. } if self.segments.len() != 1 => true, + Res::Def(DefKind::TyParam, _) if self.segments.len() != 1 => true, + Res::Def(DefKind::AssocTy, _) => true, + _ => false, + } + } + + pub(crate) fn generics(&self) -> Option> { + self.segments.last().and_then(|seg| { + if let GenericArgs::AngleBracketed { ref args, .. } = seg.args { + Some( + args.iter() + .filter_map(|arg| match arg { + GenericArg::Type(ty) => Some(ty), + _ => None, + }) + .collect(), + ) + } else { + None + } + }) + } + + pub(crate) fn bindings(&self) -> Option<&[TypeBinding]> { + self.segments.last().and_then(|seg| { + if let GenericArgs::AngleBracketed { ref bindings, .. } = seg.args { + Some(&**bindings) + } else { + None + } + }) + } +} + +#[derive(Clone, PartialEq, Eq, Debug, Hash)] +pub(crate) enum GenericArg { + Lifetime(Lifetime), + Type(Type), + Const(Box), + Infer, +} + +#[derive(Clone, PartialEq, Eq, Debug, Hash)] +pub(crate) enum GenericArgs { + AngleBracketed { args: Box<[GenericArg]>, bindings: ThinVec }, + Parenthesized { inputs: Box<[Type]>, output: Option> }, +} + +#[derive(Clone, PartialEq, Eq, Debug, Hash)] +pub(crate) struct PathSegment { + pub(crate) name: Symbol, + pub(crate) args: GenericArgs, +} + +#[derive(Clone, Debug)] +pub(crate) struct Typedef { + pub(crate) type_: Type, + pub(crate) generics: Generics, + /// `type_` can come from either the HIR or from metadata. If it comes from HIR, it may be a type + /// alias instead of the final type. This will always have the final type, regardless of whether + /// `type_` came from HIR or from metadata. + /// + /// If `item_type.is_none()`, `type_` is guaranteed to come from metadata (and therefore hold the + /// final type). + pub(crate) item_type: Option, +} + +#[derive(Clone, Debug)] +pub(crate) struct OpaqueTy { + pub(crate) bounds: Vec, + pub(crate) generics: Generics, +} + +#[derive(Clone, PartialEq, Eq, Debug, Hash)] +pub(crate) struct BareFunctionDecl { + pub(crate) unsafety: hir::Unsafety, + pub(crate) generic_params: Vec, + pub(crate) decl: FnDecl, + pub(crate) abi: Abi, +} + +#[derive(Clone, Debug)] +pub(crate) struct Static { + pub(crate) type_: Type, + pub(crate) mutability: Mutability, + pub(crate) expr: Option, +} + +#[derive(Clone, PartialEq, Eq, Hash, Debug)] +pub(crate) struct Constant { + pub(crate) type_: Type, + pub(crate) kind: ConstantKind, +} + +#[derive(Clone, PartialEq, Eq, Hash, Debug)] +pub(crate) enum Term { + Type(Type), + Constant(Constant), +} + +impl Term { + pub(crate) fn ty(&self) -> Option<&Type> { + if let Term::Type(ty) = self { Some(ty) } else { None } + } +} + +impl From for Term { + fn from(ty: Type) -> Self { + Term::Type(ty) + } +} + +#[derive(Clone, PartialEq, Eq, Hash, Debug)] +pub(crate) enum ConstantKind { + /// This is the wrapper around `ty::Const` for a non-local constant. Because it doesn't have a + /// `BodyId`, we need to handle it on its own. + /// + /// Note that `ty::Const` includes generic parameters, and may not always be uniquely identified + /// by a DefId. So this field must be different from `Extern`. + TyConst { expr: String }, + /// A constant (expression) that's not an item or associated item. These are usually found + /// nested inside types (e.g., array lengths) or expressions (e.g., repeat counts), and also + /// used to define explicit discriminant values for enum variants. + Anonymous { body: BodyId }, + /// A constant from a different crate. + Extern { def_id: DefId }, + /// `const FOO: u32 = ...;` + Local { def_id: DefId, body: BodyId }, +} + +impl Constant { + pub(crate) fn expr(&self, tcx: TyCtxt<'_>) -> String { + self.kind.expr(tcx) + } + + pub(crate) fn value(&self, tcx: TyCtxt<'_>) -> Option { + self.kind.value(tcx) + } + + pub(crate) fn is_literal(&self, tcx: TyCtxt<'_>) -> bool { + self.kind.is_literal(tcx) + } +} + +impl ConstantKind { + pub(crate) fn expr(&self, tcx: TyCtxt<'_>) -> String { + match *self { + ConstantKind::TyConst { ref expr } => expr.clone(), + ConstantKind::Extern { def_id } => print_inlined_const(tcx, def_id), + ConstantKind::Local { body, .. } | ConstantKind::Anonymous { body } => { + print_const_expr(tcx, body) + } + } + } + + pub(crate) fn value(&self, tcx: TyCtxt<'_>) -> Option { + match *self { + ConstantKind::TyConst { .. } | ConstantKind::Anonymous { .. } => None, + ConstantKind::Extern { def_id } | ConstantKind::Local { def_id, .. } => { + print_evaluated_const(tcx, def_id) + } + } + } + + pub(crate) fn is_literal(&self, tcx: TyCtxt<'_>) -> bool { + match *self { + ConstantKind::TyConst { .. } => false, + ConstantKind::Extern { def_id } => def_id.as_local().map_or(false, |def_id| { + is_literal_expr(tcx, tcx.hir().local_def_id_to_hir_id(def_id)) + }), + ConstantKind::Local { body, .. } | ConstantKind::Anonymous { body } => { + is_literal_expr(tcx, body.hir_id) + } + } + } +} + +#[derive(Clone, Debug)] +pub(crate) struct Impl { + pub(crate) unsafety: hir::Unsafety, + pub(crate) generics: Generics, + pub(crate) trait_: Option, + pub(crate) for_: Type, + pub(crate) items: Vec, + pub(crate) polarity: ty::ImplPolarity, + pub(crate) kind: ImplKind, +} + +impl Impl { + pub(crate) fn provided_trait_methods(&self, tcx: TyCtxt<'_>) -> FxHashSet { + self.trait_ + .as_ref() + .map(|t| t.def_id()) + .map(|did| tcx.provided_trait_methods(did).map(|meth| meth.name).collect()) + .unwrap_or_default() + } +} + +#[derive(Clone, Debug)] +pub(crate) enum ImplKind { + Normal, + Auto, + FakeVaradic, + Blanket(Box), +} + +impl ImplKind { + pub(crate) fn is_auto(&self) -> bool { + matches!(self, ImplKind::Auto) + } + + pub(crate) fn is_blanket(&self) -> bool { + matches!(self, ImplKind::Blanket(_)) + } + + pub(crate) fn is_fake_variadic(&self) -> bool { + matches!(self, ImplKind::FakeVaradic) + } + + pub(crate) fn as_blanket_ty(&self) -> Option<&Type> { + match self { + ImplKind::Blanket(ty) => Some(ty), + _ => None, + } + } +} + +#[derive(Clone, Debug)] +pub(crate) struct Import { + pub(crate) kind: ImportKind, + pub(crate) source: ImportSource, + pub(crate) should_be_displayed: bool, +} + +impl Import { + pub(crate) fn new_simple( + name: Symbol, + source: ImportSource, + should_be_displayed: bool, + ) -> Self { + Self { kind: ImportKind::Simple(name), source, should_be_displayed } + } + + pub(crate) fn new_glob(source: ImportSource, should_be_displayed: bool) -> Self { + Self { kind: ImportKind::Glob, source, should_be_displayed } + } +} + +#[derive(Clone, Debug)] +pub(crate) enum ImportKind { + // use source as str; + Simple(Symbol), + // use source::*; + Glob, +} + +#[derive(Clone, Debug)] +pub(crate) struct ImportSource { + pub(crate) path: Path, + pub(crate) did: Option, +} + +#[derive(Clone, Debug)] +pub(crate) struct Macro { + pub(crate) source: String, +} + +#[derive(Clone, Debug)] +pub(crate) struct ProcMacro { + pub(crate) kind: MacroKind, + pub(crate) helpers: Vec, +} + +/// An type binding on an associated type (e.g., `A = Bar` in `Foo` or +/// `A: Send + Sync` in `Foo`). +#[derive(Clone, PartialEq, Eq, Debug, Hash)] +pub(crate) struct TypeBinding { + pub(crate) assoc: PathSegment, + pub(crate) kind: TypeBindingKind, +} + +#[derive(Clone, PartialEq, Eq, Debug, Hash)] +pub(crate) enum TypeBindingKind { + Equality { term: Term }, + Constraint { bounds: Vec }, +} + +impl TypeBinding { + pub(crate) fn term(&self) -> &Term { + match self.kind { + TypeBindingKind::Equality { ref term } => term, + _ => panic!("expected equality type binding for parenthesized generic args"), + } + } +} + +/// The type, lifetime, or constant that a private type alias's parameter should be +/// replaced with when expanding a use of that type alias. +/// +/// For example: +/// +/// ``` +/// type PrivAlias = Vec; +/// +/// pub fn public_fn() -> PrivAlias { vec![] } +/// ``` +/// +/// `public_fn`'s docs will show it as returning `Vec`, since `PrivAlias` is private. +/// [`SubstParam`] is used to record that `T` should be mapped to `i32`. +pub(crate) enum SubstParam { + Type(Type), + Lifetime(Lifetime), + Constant(Constant), +} + +impl SubstParam { + pub(crate) fn as_ty(&self) -> Option<&Type> { + if let Self::Type(ty) = self { Some(ty) } else { None } + } + + pub(crate) fn as_lt(&self) -> Option<&Lifetime> { + if let Self::Lifetime(lt) = self { Some(lt) } else { None } + } +} + +// Some nodes are used a lot. Make sure they don't unintentionally get bigger. +#[cfg(all(target_arch = "x86_64", target_pointer_width = "64"))] +mod size_asserts { + use super::*; + // These are in alphabetical order, which is easy to maintain. + rustc_data_structures::static_assert_size!(Crate, 72); // frequently moved by-value + rustc_data_structures::static_assert_size!(DocFragment, 32); + rustc_data_structures::static_assert_size!(GenericArg, 80); + rustc_data_structures::static_assert_size!(GenericArgs, 32); + rustc_data_structures::static_assert_size!(GenericParamDef, 56); + rustc_data_structures::static_assert_size!(Item, 56); + rustc_data_structures::static_assert_size!(ItemKind, 112); + rustc_data_structures::static_assert_size!(PathSegment, 40); + rustc_data_structures::static_assert_size!(Type, 72); +} diff --git a/src/librustdoc/clean/types/tests.rs b/src/librustdoc/clean/types/tests.rs new file mode 100644 index 000000000..71eddf434 --- /dev/null +++ b/src/librustdoc/clean/types/tests.rs @@ -0,0 +1,70 @@ +use super::*; + +use crate::clean::collapse_doc_fragments; + +use rustc_span::create_default_session_globals_then; +use rustc_span::source_map::DUMMY_SP; +use rustc_span::symbol::Symbol; + +fn create_doc_fragment(s: &str) -> Vec { + vec![DocFragment { + span: DUMMY_SP, + parent_module: None, + doc: Symbol::intern(s), + kind: DocFragmentKind::SugaredDoc, + indent: 0, + }] +} + +#[track_caller] +fn run_test(input: &str, expected: &str) { + create_default_session_globals_then(|| { + let mut s = create_doc_fragment(input); + unindent_doc_fragments(&mut s); + assert_eq!(collapse_doc_fragments(&s), expected); + }); +} + +#[test] +fn should_unindent() { + run_test(" line1\n line2", "line1\nline2"); +} + +#[test] +fn should_unindent_multiple_paragraphs() { + run_test(" line1\n\n line2", "line1\n\nline2"); +} + +#[test] +fn should_leave_multiple_indent_levels() { + // Line 2 is indented another level beyond the + // base indentation and should be preserved + run_test(" line1\n\n line2", "line1\n\n line2"); +} + +#[test] +fn should_ignore_first_line_indent() { + run_test("line1\n line2", "line1\n line2"); +} + +#[test] +fn should_not_ignore_first_line_indent_in_a_single_line_para() { + run_test("line1\n\n line2", "line1\n\n line2"); +} + +#[test] +fn should_unindent_tabs() { + run_test("\tline1\n\tline2", "line1\nline2"); +} + +#[test] +fn should_trim_mixed_indentation() { + run_test("\t line1\n\t line2", "line1\nline2"); + run_test(" \tline1\n \tline2", "line1\nline2"); +} + +#[test] +fn should_not_trim() { + run_test("\t line1 \n\t line2", "line1 \nline2"); + run_test(" \tline1 \n \tline2", "line1 \nline2"); +} diff --git a/src/librustdoc/clean/utils.rs b/src/librustdoc/clean/utils.rs new file mode 100644 index 000000000..43e71e90a --- /dev/null +++ b/src/librustdoc/clean/utils.rs @@ -0,0 +1,616 @@ +use crate::clean::auto_trait::AutoTraitFinder; +use crate::clean::blanket_impl::BlanketImplFinder; +use crate::clean::render_macro_matchers::render_macro_matcher; +use crate::clean::{ + clean_middle_const, clean_middle_region, clean_middle_ty, inline, Clean, Crate, ExternalCrate, + Generic, GenericArg, GenericArgs, ImportSource, Item, ItemKind, Lifetime, Path, PathSegment, + Primitive, PrimitiveType, Type, TypeBinding, Visibility, +}; +use crate::core::DocContext; +use crate::formats::item_type::ItemType; +use crate::visit_lib::LibEmbargoVisitor; + +use rustc_ast as ast; +use rustc_ast::tokenstream::TokenTree; +use rustc_data_structures::thin_vec::ThinVec; +use rustc_hir as hir; +use rustc_hir::def::{DefKind, Res}; +use rustc_hir::def_id::{DefId, LOCAL_CRATE}; +use rustc_middle::mir; +use rustc_middle::mir::interpret::ConstValue; +use rustc_middle::ty::subst::{GenericArgKind, SubstsRef}; +use rustc_middle::ty::{self, DefIdTree, TyCtxt}; +use rustc_span::symbol::{kw, sym, Symbol}; +use std::fmt::Write as _; +use std::mem; + +#[cfg(test)] +mod tests; + +pub(crate) fn krate(cx: &mut DocContext<'_>) -> Crate { + let module = crate::visit_ast::RustdocVisitor::new(cx).visit(); + + for &cnum in cx.tcx.crates(()) { + // Analyze doc-reachability for extern items + LibEmbargoVisitor::new(cx).visit_lib(cnum); + } + + // Clean the crate, translating the entire librustc_ast AST to one that is + // understood by rustdoc. + let mut module = module.clean(cx); + + match *module.kind { + ItemKind::ModuleItem(ref module) => { + for it in &module.items { + // `compiler_builtins` should be masked too, but we can't apply + // `#[doc(masked)]` to the injected `extern crate` because it's unstable. + if it.is_extern_crate() + && (it.attrs.has_doc_flag(sym::masked) + || cx.tcx.is_compiler_builtins(it.item_id.krate())) + { + cx.cache.masked_crates.insert(it.item_id.krate()); + } + } + } + _ => unreachable!(), + } + + let local_crate = ExternalCrate { crate_num: LOCAL_CRATE }; + let primitives = local_crate.primitives(cx.tcx); + let keywords = local_crate.keywords(cx.tcx); + { + let ItemKind::ModuleItem(ref mut m) = *module.kind + else { unreachable!() }; + m.items.extend(primitives.iter().map(|&(def_id, prim)| { + Item::from_def_id_and_parts( + def_id, + Some(prim.as_sym()), + ItemKind::PrimitiveItem(prim), + cx, + ) + })); + m.items.extend(keywords.into_iter().map(|(def_id, kw)| { + Item::from_def_id_and_parts(def_id, Some(kw), ItemKind::KeywordItem, cx) + })); + } + + Crate { module, primitives, external_traits: cx.external_traits.clone() } +} + +pub(crate) fn substs_to_args<'tcx>( + cx: &mut DocContext<'tcx>, + substs: &[ty::subst::GenericArg<'tcx>], + mut skip_first: bool, +) -> Vec { + let mut ret_val = + Vec::with_capacity(substs.len().saturating_sub(if skip_first { 1 } else { 0 })); + ret_val.extend(substs.iter().filter_map(|kind| match kind.unpack() { + GenericArgKind::Lifetime(lt) => { + Some(GenericArg::Lifetime(clean_middle_region(lt).unwrap_or(Lifetime::elided()))) + } + GenericArgKind::Type(_) if skip_first => { + skip_first = false; + None + } + GenericArgKind::Type(ty) => Some(GenericArg::Type(clean_middle_ty(ty, cx, None))), + GenericArgKind::Const(ct) => Some(GenericArg::Const(Box::new(clean_middle_const(ct, cx)))), + })); + ret_val +} + +fn external_generic_args<'tcx>( + cx: &mut DocContext<'tcx>, + did: DefId, + has_self: bool, + bindings: Vec, + substs: SubstsRef<'tcx>, +) -> GenericArgs { + let args = substs_to_args(cx, substs, has_self); + + if cx.tcx.fn_trait_kind_from_lang_item(did).is_some() { + let inputs = + // The trait's first substitution is the one after self, if there is one. + match substs.iter().nth(if has_self { 1 } else { 0 }).unwrap().expect_ty().kind() { + ty::Tuple(tys) => tys.iter().map(|t| clean_middle_ty(t, cx, None)).collect::>().into(), + _ => return GenericArgs::AngleBracketed { args: args.into(), bindings: bindings.into() }, + }; + let output = None; + // FIXME(#20299) return type comes from a projection now + // match types[1].kind { + // ty::Tuple(ref v) if v.is_empty() => None, // -> () + // _ => Some(types[1].clean(cx)) + // }; + GenericArgs::Parenthesized { inputs, output } + } else { + GenericArgs::AngleBracketed { args: args.into(), bindings: bindings.into() } + } +} + +pub(super) fn external_path<'tcx>( + cx: &mut DocContext<'tcx>, + did: DefId, + has_self: bool, + bindings: Vec, + substs: SubstsRef<'tcx>, +) -> Path { + let def_kind = cx.tcx.def_kind(did); + let name = cx.tcx.item_name(did); + Path { + res: Res::Def(def_kind, did), + segments: vec![PathSegment { + name, + args: external_generic_args(cx, did, has_self, bindings, substs), + }], + } +} + +/// Remove the generic arguments from a path. +pub(crate) fn strip_path_generics(mut path: Path) -> Path { + for ps in path.segments.iter_mut() { + ps.args = GenericArgs::AngleBracketed { args: Default::default(), bindings: ThinVec::new() } + } + + path +} + +pub(crate) fn qpath_to_string(p: &hir::QPath<'_>) -> String { + let segments = match *p { + hir::QPath::Resolved(_, path) => &path.segments, + hir::QPath::TypeRelative(_, segment) => return segment.ident.to_string(), + hir::QPath::LangItem(lang_item, ..) => return lang_item.name().to_string(), + }; + + let mut s = String::new(); + for (i, seg) in segments.iter().enumerate() { + if i > 0 { + s.push_str("::"); + } + if seg.ident.name != kw::PathRoot { + s.push_str(seg.ident.as_str()); + } + } + s +} + +pub(crate) fn build_deref_target_impls( + cx: &mut DocContext<'_>, + items: &[Item], + ret: &mut Vec, +) { + let tcx = cx.tcx; + + for item in items { + let target = match *item.kind { + ItemKind::AssocTypeItem(ref t, _) => &t.type_, + _ => continue, + }; + + if let Some(prim) = target.primitive_type() { + let _prof_timer = cx.tcx.sess.prof.generic_activity("build_primitive_inherent_impls"); + for did in prim.impls(tcx).filter(|did| !did.is_local()) { + inline::build_impl(cx, None, did, None, ret); + } + } else if let Type::Path { path } = target { + let did = path.def_id(); + if !did.is_local() { + inline::build_impls(cx, None, did, None, ret); + } + } + } +} + +pub(crate) fn name_from_pat(p: &hir::Pat<'_>) -> Symbol { + use rustc_hir::*; + debug!("trying to get a name from pattern: {:?}", p); + + Symbol::intern(&match p.kind { + PatKind::Wild | PatKind::Struct(..) => return kw::Underscore, + PatKind::Binding(_, _, ident, _) => return ident.name, + PatKind::TupleStruct(ref p, ..) | PatKind::Path(ref p) => qpath_to_string(p), + PatKind::Or(pats) => { + pats.iter().map(|p| name_from_pat(p).to_string()).collect::>().join(" | ") + } + PatKind::Tuple(elts, _) => format!( + "({})", + elts.iter().map(|p| name_from_pat(p).to_string()).collect::>().join(", ") + ), + PatKind::Box(p) => return name_from_pat(&*p), + PatKind::Ref(p, _) => return name_from_pat(&*p), + PatKind::Lit(..) => { + warn!( + "tried to get argument name from PatKind::Lit, which is silly in function arguments" + ); + return Symbol::intern("()"); + } + PatKind::Range(..) => return kw::Underscore, + PatKind::Slice(begin, ref mid, end) => { + let begin = begin.iter().map(|p| name_from_pat(p).to_string()); + let mid = mid.as_ref().map(|p| format!("..{}", name_from_pat(&**p))).into_iter(); + let end = end.iter().map(|p| name_from_pat(p).to_string()); + format!("[{}]", begin.chain(mid).chain(end).collect::>().join(", ")) + } + }) +} + +pub(crate) fn print_const(cx: &DocContext<'_>, n: ty::Const<'_>) -> String { + match n.kind() { + ty::ConstKind::Unevaluated(ty::Unevaluated { def, substs: _, promoted }) => { + let mut s = if let Some(def) = def.as_local() { + print_const_expr(cx.tcx, cx.tcx.hir().body_owned_by(def.did)) + } else { + inline::print_inlined_const(cx.tcx, def.did) + }; + if let Some(promoted) = promoted { + s.push_str(&format!("::{:?}", promoted)) + } + s + } + _ => { + let mut s = n.to_string(); + // array lengths are obviously usize + if s.ends_with("_usize") { + let n = s.len() - "_usize".len(); + s.truncate(n); + if s.ends_with(": ") { + let n = s.len() - ": ".len(); + s.truncate(n); + } + } + s + } + } +} + +pub(crate) fn print_evaluated_const(tcx: TyCtxt<'_>, def_id: DefId) -> Option { + tcx.const_eval_poly(def_id).ok().and_then(|val| { + let ty = tcx.type_of(def_id); + match (val, ty.kind()) { + (_, &ty::Ref(..)) => None, + (ConstValue::Scalar(_), &ty::Adt(_, _)) => None, + (ConstValue::Scalar(_), _) => { + let const_ = mir::ConstantKind::from_value(val, ty); + Some(print_const_with_custom_print_scalar(tcx, const_)) + } + _ => None, + } + }) +} + +fn format_integer_with_underscore_sep(num: &str) -> String { + let num_chars: Vec<_> = num.chars().collect(); + let mut num_start_index = if num_chars.get(0) == Some(&'-') { 1 } else { 0 }; + let chunk_size = match num[num_start_index..].as_bytes() { + [b'0', b'b' | b'x', ..] => { + num_start_index += 2; + 4 + } + [b'0', b'o', ..] => { + num_start_index += 2; + let remaining_chars = num_chars.len() - num_start_index; + if remaining_chars <= 6 { + // don't add underscores to Unix permissions like 0755 or 100755 + return num.to_string(); + } + 3 + } + _ => 3, + }; + + num_chars[..num_start_index] + .iter() + .chain(num_chars[num_start_index..].rchunks(chunk_size).rev().intersperse(&['_']).flatten()) + .collect() +} + +fn print_const_with_custom_print_scalar(tcx: TyCtxt<'_>, ct: mir::ConstantKind<'_>) -> String { + // Use a slightly different format for integer types which always shows the actual value. + // For all other types, fallback to the original `pretty_print_const`. + match (ct, ct.ty().kind()) { + (mir::ConstantKind::Val(ConstValue::Scalar(int), _), ty::Uint(ui)) => { + format!("{}{}", format_integer_with_underscore_sep(&int.to_string()), ui.name_str()) + } + (mir::ConstantKind::Val(ConstValue::Scalar(int), _), ty::Int(i)) => { + let ty = tcx.lift(ct.ty()).unwrap(); + let size = tcx.layout_of(ty::ParamEnv::empty().and(ty)).unwrap().size; + let data = int.assert_bits(size); + let sign_extended_data = size.sign_extend(data) as i128; + format!( + "{}{}", + format_integer_with_underscore_sep(&sign_extended_data.to_string()), + i.name_str() + ) + } + _ => ct.to_string(), + } +} + +pub(crate) fn is_literal_expr(tcx: TyCtxt<'_>, hir_id: hir::HirId) -> bool { + if let hir::Node::Expr(expr) = tcx.hir().get(hir_id) { + if let hir::ExprKind::Lit(_) = &expr.kind { + return true; + } + + if let hir::ExprKind::Unary(hir::UnOp::Neg, expr) = &expr.kind { + if let hir::ExprKind::Lit(_) = &expr.kind { + return true; + } + } + } + + false +} + +/// Build a textual representation of an unevaluated constant expression. +/// +/// If the const expression is too complex, an underscore `_` is returned. +/// For const arguments, it's `{ _ }` to be precise. +/// This means that the output is not necessarily valid Rust code. +/// +/// Currently, only +/// +/// * literals (optionally with a leading `-`) +/// * unit `()` +/// * blocks (`{ … }`) around simple expressions and +/// * paths without arguments +/// +/// are considered simple enough. Simple blocks are included since they are +/// necessary to disambiguate unit from the unit type. +/// This list might get extended in the future. +/// +/// Without this censoring, in a lot of cases the output would get too large +/// and verbose. Consider `match` expressions, blocks and deeply nested ADTs. +/// Further, private and `doc(hidden)` fields of structs would get leaked +/// since HIR datatypes like the `body` parameter do not contain enough +/// semantic information for this function to be able to hide them – +/// at least not without significant performance overhead. +/// +/// Whenever possible, prefer to evaluate the constant first and try to +/// use a different method for pretty-printing. Ideally this function +/// should only ever be used as a fallback. +pub(crate) fn print_const_expr(tcx: TyCtxt<'_>, body: hir::BodyId) -> String { + let hir = tcx.hir(); + let value = &hir.body(body).value; + + #[derive(PartialEq, Eq)] + enum Classification { + Literal, + Simple, + Complex, + } + + use Classification::*; + + fn classify(expr: &hir::Expr<'_>) -> Classification { + match &expr.kind { + hir::ExprKind::Unary(hir::UnOp::Neg, expr) => { + if matches!(expr.kind, hir::ExprKind::Lit(_)) { Literal } else { Complex } + } + hir::ExprKind::Lit(_) => Literal, + hir::ExprKind::Tup([]) => Simple, + hir::ExprKind::Block(hir::Block { stmts: [], expr: Some(expr), .. }, _) => { + if classify(expr) == Complex { Complex } else { Simple } + } + // Paths with a self-type or arguments are too “complex” following our measure since + // they may leak private fields of structs (with feature `adt_const_params`). + // Consider: `>::CONSTANT`. + // Paths without arguments are definitely harmless though. + hir::ExprKind::Path(hir::QPath::Resolved(_, hir::Path { segments, .. })) => { + if segments.iter().all(|segment| segment.args.is_none()) { Simple } else { Complex } + } + // FIXME: Claiming that those kinds of QPaths are simple is probably not true if the Ty + // contains const arguments. Is there a *concise* way to check for this? + hir::ExprKind::Path(hir::QPath::TypeRelative(..)) => Simple, + // FIXME: Can they contain const arguments and thus leak private struct fields? + hir::ExprKind::Path(hir::QPath::LangItem(..)) => Simple, + _ => Complex, + } + } + + let classification = classify(value); + + if classification == Literal + && !value.span.from_expansion() + && let Ok(snippet) = tcx.sess.source_map().span_to_snippet(value.span) { + // For literals, we avoid invoking the pretty-printer and use the source snippet instead to + // preserve certain stylistic choices the user likely made for the sake legibility like + // + // * hexadecimal notation + // * underscores + // * character escapes + // + // FIXME: This passes through `-/*spacer*/0` verbatim. + snippet + } else if classification == Simple { + // Otherwise we prefer pretty-printing to get rid of extraneous whitespace, comments and + // other formatting artifacts. + rustc_hir_pretty::id_to_string(&hir, body.hir_id) + } else if tcx.def_kind(hir.body_owner_def_id(body).to_def_id()) == DefKind::AnonConst { + // FIXME: Omit the curly braces if the enclosing expression is an array literal + // with a repeated element (an `ExprKind::Repeat`) as in such case it + // would not actually need any disambiguation. + "{ _ }".to_owned() + } else { + "_".to_owned() + } +} + +/// Given a type Path, resolve it to a Type using the TyCtxt +pub(crate) fn resolve_type(cx: &mut DocContext<'_>, path: Path) -> Type { + debug!("resolve_type({:?})", path); + + match path.res { + Res::PrimTy(p) => Primitive(PrimitiveType::from(p)), + Res::SelfTy { .. } if path.segments.len() == 1 => Generic(kw::SelfUpper), + Res::Def(DefKind::TyParam, _) if path.segments.len() == 1 => Generic(path.segments[0].name), + _ => { + let _ = register_res(cx, path.res); + Type::Path { path } + } + } +} + +pub(crate) fn get_auto_trait_and_blanket_impls( + cx: &mut DocContext<'_>, + item_def_id: DefId, +) -> impl Iterator { + let auto_impls = cx + .sess() + .prof + .generic_activity("get_auto_trait_impls") + .run(|| AutoTraitFinder::new(cx).get_auto_trait_impls(item_def_id)); + let blanket_impls = cx + .sess() + .prof + .generic_activity("get_blanket_impls") + .run(|| BlanketImplFinder { cx }.get_blanket_impls(item_def_id)); + auto_impls.into_iter().chain(blanket_impls) +} + +/// If `res` has a documentation page associated, store it in the cache. +/// +/// This is later used by [`href()`] to determine the HTML link for the item. +/// +/// [`href()`]: crate::html::format::href +pub(crate) fn register_res(cx: &mut DocContext<'_>, res: Res) -> DefId { + use DefKind::*; + debug!("register_res({:?})", res); + + let (did, kind) = match res { + // These should be added to the cache using `record_extern_fqn`. + Res::Def( + kind @ (AssocTy | AssocFn | AssocConst | Variant | Fn | TyAlias | Enum | Trait | Struct + | Union | Mod | ForeignTy | Const | Static(_) | Macro(..) | TraitAlias), + i, + ) => (i, kind.into()), + // This is part of a trait definition or trait impl; document the trait. + Res::SelfTy { trait_: Some(trait_def_id), alias_to: _ } => (trait_def_id, ItemType::Trait), + // This is an inherent impl or a type definition; it doesn't have its own page. + Res::SelfTy { trait_: None, alias_to: Some((item_def_id, _)) } => return item_def_id, + Res::SelfTy { trait_: None, alias_to: None } + | Res::PrimTy(_) + | Res::ToolMod + | Res::SelfCtor(_) + | Res::Local(_) + | Res::NonMacroAttr(_) + | Res::Err => return res.def_id(), + Res::Def( + TyParam | ConstParam | Ctor(..) | ExternCrate | Use | ForeignMod | AnonConst + | InlineConst | OpaqueTy | Field | LifetimeParam | GlobalAsm | Impl | Closure + | Generator, + id, + ) => return id, + }; + if did.is_local() { + return did; + } + inline::record_extern_fqn(cx, did, kind); + if let ItemType::Trait = kind { + inline::record_extern_trait(cx, did); + } + did +} + +pub(crate) fn resolve_use_source(cx: &mut DocContext<'_>, path: Path) -> ImportSource { + ImportSource { + did: if path.res.opt_def_id().is_none() { None } else { Some(register_res(cx, path.res)) }, + path, + } +} + +pub(crate) fn enter_impl_trait<'tcx, F, R>(cx: &mut DocContext<'tcx>, f: F) -> R +where + F: FnOnce(&mut DocContext<'tcx>) -> R, +{ + let old_bounds = mem::take(&mut cx.impl_trait_bounds); + let r = f(cx); + assert!(cx.impl_trait_bounds.is_empty()); + cx.impl_trait_bounds = old_bounds; + r +} + +/// Find the nearest parent module of a [`DefId`]. +pub(crate) fn find_nearest_parent_module(tcx: TyCtxt<'_>, def_id: DefId) -> Option { + if def_id.is_top_level_module() { + // The crate root has no parent. Use it as the root instead. + Some(def_id) + } else { + let mut current = def_id; + // The immediate parent might not always be a module. + // Find the first parent which is. + while let Some(parent) = tcx.opt_parent(current) { + if tcx.def_kind(parent) == DefKind::Mod { + return Some(parent); + } + current = parent; + } + None + } +} + +/// Checks for the existence of `hidden` in the attribute below if `flag` is `sym::hidden`: +/// +/// ``` +/// #[doc(hidden)] +/// pub fn foo() {} +/// ``` +/// +/// This function exists because it runs on `hir::Attributes` whereas the other is a +/// `clean::Attributes` method. +pub(crate) fn has_doc_flag(tcx: TyCtxt<'_>, did: DefId, flag: Symbol) -> bool { + tcx.get_attrs(did, sym::doc).any(|attr| { + attr.meta_item_list().map_or(false, |l| rustc_attr::list_contains_name(&l, flag)) + }) +} + +/// A link to `doc.rust-lang.org` that includes the channel name. Use this instead of manual links +/// so that the channel is consistent. +/// +/// Set by `bootstrap::Builder::doc_rust_lang_org_channel` in order to keep tests passing on beta/stable. +pub(crate) const DOC_RUST_LANG_ORG_CHANNEL: &str = env!("DOC_RUST_LANG_ORG_CHANNEL"); + +/// Render a sequence of macro arms in a format suitable for displaying to the user +/// as part of an item declaration. +pub(super) fn render_macro_arms<'a>( + tcx: TyCtxt<'_>, + matchers: impl Iterator, + arm_delim: &str, +) -> String { + let mut out = String::new(); + for matcher in matchers { + writeln!(out, " {} => {{ ... }}{}", render_macro_matcher(tcx, matcher), arm_delim) + .unwrap(); + } + out +} + +pub(super) fn display_macro_source( + cx: &mut DocContext<'_>, + name: Symbol, + def: &ast::MacroDef, + def_id: DefId, + vis: Visibility, +) -> String { + let tts: Vec<_> = def.body.inner_tokens().into_trees().collect(); + // Extract the spans of all matchers. They represent the "interface" of the macro. + let matchers = tts.chunks(4).map(|arm| &arm[0]); + + if def.macro_rules { + format!("macro_rules! {} {{\n{}}}", name, render_macro_arms(cx.tcx, matchers, ";")) + } else { + if matchers.len() <= 1 { + format!( + "{}macro {}{} {{\n ...\n}}", + vis.to_src_with_space(cx.tcx, def_id), + name, + matchers.map(|matcher| render_macro_matcher(cx.tcx, matcher)).collect::(), + ) + } else { + format!( + "{}macro {} {{\n{}}}", + vis.to_src_with_space(cx.tcx, def_id), + name, + render_macro_arms(cx.tcx, matchers, ","), + ) + } + } +} diff --git a/src/librustdoc/clean/utils/tests.rs b/src/librustdoc/clean/utils/tests.rs new file mode 100644 index 000000000..ebf4b4954 --- /dev/null +++ b/src/librustdoc/clean/utils/tests.rs @@ -0,0 +1,41 @@ +use super::*; + +#[test] +fn int_format_decimal() { + assert_eq!(format_integer_with_underscore_sep("12345678"), "12_345_678"); + assert_eq!(format_integer_with_underscore_sep("123"), "123"); + assert_eq!(format_integer_with_underscore_sep("123459"), "123_459"); + assert_eq!(format_integer_with_underscore_sep("-12345678"), "-12_345_678"); + assert_eq!(format_integer_with_underscore_sep("-123"), "-123"); + assert_eq!(format_integer_with_underscore_sep("-123459"), "-123_459"); +} + +#[test] +fn int_format_hex() { + assert_eq!(format_integer_with_underscore_sep("0xab3"), "0xab3"); + assert_eq!(format_integer_with_underscore_sep("0xa2345b"), "0xa2_345b"); + assert_eq!(format_integer_with_underscore_sep("0xa2e6345b"), "0xa2e6_345b"); + assert_eq!(format_integer_with_underscore_sep("-0xab3"), "-0xab3"); + assert_eq!(format_integer_with_underscore_sep("-0xa2345b"), "-0xa2_345b"); + assert_eq!(format_integer_with_underscore_sep("-0xa2e6345b"), "-0xa2e6_345b"); +} + +#[test] +fn int_format_binary() { + assert_eq!(format_integer_with_underscore_sep("0o12345671"), "0o12_345_671"); + assert_eq!(format_integer_with_underscore_sep("0o123"), "0o123"); + assert_eq!(format_integer_with_underscore_sep("0o123451"), "0o123451"); + assert_eq!(format_integer_with_underscore_sep("-0o12345671"), "-0o12_345_671"); + assert_eq!(format_integer_with_underscore_sep("-0o123"), "-0o123"); + assert_eq!(format_integer_with_underscore_sep("-0o123451"), "-0o123451"); +} + +#[test] +fn int_format_octal() { + assert_eq!(format_integer_with_underscore_sep("0b101"), "0b101"); + assert_eq!(format_integer_with_underscore_sep("0b101101011"), "0b1_0110_1011"); + assert_eq!(format_integer_with_underscore_sep("0b01101011"), "0b0110_1011"); + assert_eq!(format_integer_with_underscore_sep("-0b101"), "-0b101"); + assert_eq!(format_integer_with_underscore_sep("-0b101101011"), "-0b1_0110_1011"); + assert_eq!(format_integer_with_underscore_sep("-0b01101011"), "-0b0110_1011"); +} diff --git a/src/librustdoc/config.rs b/src/librustdoc/config.rs new file mode 100644 index 000000000..8a8cc272e --- /dev/null +++ b/src/librustdoc/config.rs @@ -0,0 +1,828 @@ +use std::collections::BTreeMap; +use std::convert::TryFrom; +use std::ffi::OsStr; +use std::fmt; +use std::path::PathBuf; +use std::str::FromStr; + +use rustc_data_structures::fx::FxHashMap; +use rustc_driver::print_flag_list; +use rustc_session::config::{ + self, parse_crate_types_from_list, parse_externs, parse_target_triple, CrateType, +}; +use rustc_session::config::{get_cmd_lint_options, nightly_options}; +use rustc_session::config::{ + CodegenOptions, ErrorOutputType, Externs, JsonUnusedExterns, UnstableOptions, +}; +use rustc_session::getopts; +use rustc_session::lint::Level; +use rustc_session::search_paths::SearchPath; +use rustc_span::edition::Edition; +use rustc_target::spec::TargetTriple; + +use crate::core::new_handler; +use crate::externalfiles::ExternalHtml; +use crate::html; +use crate::html::markdown::IdMap; +use crate::html::render::StylePath; +use crate::html::static_files; +use crate::opts; +use crate::passes::{self, Condition}; +use crate::scrape_examples::{AllCallLocations, ScrapeExamplesOptions}; +use crate::theme; + +#[derive(Clone, Copy, PartialEq, Eq, Debug)] +pub(crate) enum OutputFormat { + Json, + Html, +} + +impl Default for OutputFormat { + fn default() -> OutputFormat { + OutputFormat::Html + } +} + +impl OutputFormat { + pub(crate) fn is_json(&self) -> bool { + matches!(self, OutputFormat::Json) + } +} + +impl TryFrom<&str> for OutputFormat { + type Error = String; + + fn try_from(value: &str) -> Result { + match value { + "json" => Ok(OutputFormat::Json), + "html" => Ok(OutputFormat::Html), + _ => Err(format!("unknown output format `{}`", value)), + } + } +} + +/// Configuration options for rustdoc. +#[derive(Clone)] +pub(crate) struct Options { + // Basic options / Options passed directly to rustc + /// The crate root or Markdown file to load. + pub(crate) input: PathBuf, + /// The name of the crate being documented. + pub(crate) crate_name: Option, + /// Whether or not this is a proc-macro crate + pub(crate) proc_macro_crate: bool, + /// How to format errors and warnings. + pub(crate) error_format: ErrorOutputType, + /// Width of output buffer to truncate errors appropriately. + pub(crate) diagnostic_width: Option, + /// Library search paths to hand to the compiler. + pub(crate) libs: Vec, + /// Library search paths strings to hand to the compiler. + pub(crate) lib_strs: Vec, + /// The list of external crates to link against. + pub(crate) externs: Externs, + /// The list of external crates strings to link against. + pub(crate) extern_strs: Vec, + /// List of `cfg` flags to hand to the compiler. Always includes `rustdoc`. + pub(crate) cfgs: Vec, + /// List of check cfg flags to hand to the compiler. + pub(crate) check_cfgs: Vec, + /// Codegen options to hand to the compiler. + pub(crate) codegen_options: CodegenOptions, + /// Codegen options strings to hand to the compiler. + pub(crate) codegen_options_strs: Vec, + /// Unstable (`-Z`) options to pass to the compiler. + pub(crate) unstable_opts: UnstableOptions, + /// Unstable (`-Z`) options strings to pass to the compiler. + pub(crate) unstable_opts_strs: Vec, + /// The target used to compile the crate against. + pub(crate) target: TargetTriple, + /// Edition used when reading the crate. Defaults to "2015". Also used by default when + /// compiling doctests from the crate. + pub(crate) edition: Edition, + /// The path to the sysroot. Used during the compilation process. + pub(crate) maybe_sysroot: Option, + /// Lint information passed over the command-line. + pub(crate) lint_opts: Vec<(String, Level)>, + /// Whether to ask rustc to describe the lints it knows. + pub(crate) describe_lints: bool, + /// What level to cap lints at. + pub(crate) lint_cap: Option, + + // Options specific to running doctests + /// Whether we should run doctests instead of generating docs. + pub(crate) should_test: bool, + /// List of arguments to pass to the test harness, if running tests. + pub(crate) test_args: Vec, + /// The working directory in which to run tests. + pub(crate) test_run_directory: Option, + /// Optional path to persist the doctest executables to, defaults to a + /// temporary directory if not set. + pub(crate) persist_doctests: Option, + /// Runtool to run doctests with + pub(crate) runtool: Option, + /// Arguments to pass to the runtool + pub(crate) runtool_args: Vec, + /// Whether to allow ignoring doctests on a per-target basis + /// For example, using ignore-foo to ignore running the doctest on any target that + /// contains "foo" as a substring + pub(crate) enable_per_target_ignores: bool, + /// Do not run doctests, compile them if should_test is active. + pub(crate) no_run: bool, + + /// The path to a rustc-like binary to build tests with. If not set, we + /// default to loading from `$sysroot/bin/rustc`. + pub(crate) test_builder: Option, + + // Options that affect the documentation process + /// Whether to run the `calculate-doc-coverage` pass, which counts the number of public items + /// with and without documentation. + pub(crate) show_coverage: bool, + + // Options that alter generated documentation pages + /// Crate version to note on the sidebar of generated docs. + pub(crate) crate_version: Option, + /// Collected options specific to outputting final pages. + pub(crate) render_options: RenderOptions, + /// The format that we output when rendering. + /// + /// Currently used only for the `--show-coverage` option. + pub(crate) output_format: OutputFormat, + /// If this option is set to `true`, rustdoc will only run checks and not generate + /// documentation. + pub(crate) run_check: bool, + /// Whether doctests should emit unused externs + pub(crate) json_unused_externs: JsonUnusedExterns, + /// Whether to skip capturing stdout and stderr of tests. + pub(crate) nocapture: bool, + + /// Configuration for scraping examples from the current crate. If this option is Some(..) then + /// the compiler will scrape examples and not generate documentation. + pub(crate) scrape_examples_options: Option, +} + +impl fmt::Debug for Options { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + struct FmtExterns<'a>(&'a Externs); + + impl<'a> fmt::Debug for FmtExterns<'a> { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.debug_map().entries(self.0.iter()).finish() + } + } + + f.debug_struct("Options") + .field("input", &self.input) + .field("crate_name", &self.crate_name) + .field("proc_macro_crate", &self.proc_macro_crate) + .field("error_format", &self.error_format) + .field("libs", &self.libs) + .field("externs", &FmtExterns(&self.externs)) + .field("cfgs", &self.cfgs) + .field("check-cfgs", &self.check_cfgs) + .field("codegen_options", &"...") + .field("unstable_options", &"...") + .field("target", &self.target) + .field("edition", &self.edition) + .field("maybe_sysroot", &self.maybe_sysroot) + .field("lint_opts", &self.lint_opts) + .field("describe_lints", &self.describe_lints) + .field("lint_cap", &self.lint_cap) + .field("should_test", &self.should_test) + .field("test_args", &self.test_args) + .field("test_run_directory", &self.test_run_directory) + .field("persist_doctests", &self.persist_doctests) + .field("show_coverage", &self.show_coverage) + .field("crate_version", &self.crate_version) + .field("render_options", &self.render_options) + .field("runtool", &self.runtool) + .field("runtool_args", &self.runtool_args) + .field("enable-per-target-ignores", &self.enable_per_target_ignores) + .field("run_check", &self.run_check) + .field("no_run", &self.no_run) + .field("nocapture", &self.nocapture) + .field("scrape_examples_options", &self.scrape_examples_options) + .finish() + } +} + +/// Configuration options for the HTML page-creation process. +#[derive(Clone, Debug)] +pub(crate) struct RenderOptions { + /// Output directory to generate docs into. Defaults to `doc`. + pub(crate) output: PathBuf, + /// External files to insert into generated pages. + pub(crate) external_html: ExternalHtml, + /// A pre-populated `IdMap` with the default headings and any headings added by Markdown files + /// processed by `external_html`. + pub(crate) id_map: IdMap, + /// If present, playground URL to use in the "Run" button added to code samples. + /// + /// Be aware: This option can come both from the CLI and from crate attributes! + pub(crate) playground_url: Option, + /// What sorting mode to use for module pages. + /// `ModuleSorting::Alphabetical` by default. + pub(crate) module_sorting: ModuleSorting, + /// List of themes to extend the docs with. Original argument name is included to assist in + /// displaying errors if it fails a theme check. + pub(crate) themes: Vec, + /// If present, CSS file that contains rules to add to the default CSS. + pub(crate) extension_css: Option, + /// A map of crate names to the URL to use instead of querying the crate's `html_root_url`. + pub(crate) extern_html_root_urls: BTreeMap, + /// Whether to give precedence to `html_root_url` or `--exten-html-root-url`. + pub(crate) extern_html_root_takes_precedence: bool, + /// A map of the default settings (values are as for DOM storage API). Keys should lack the + /// `rustdoc-` prefix. + pub(crate) default_settings: FxHashMap, + /// If present, suffix added to CSS/JavaScript files when referencing them in generated pages. + pub(crate) resource_suffix: String, + /// Whether to run the static CSS/JavaScript through a minifier when outputting them. `true` by + /// default. + pub(crate) enable_minification: bool, + /// Whether to create an index page in the root of the output directory. If this is true but + /// `enable_index_page` is None, generate a static listing of crates instead. + pub(crate) enable_index_page: bool, + /// A file to use as the index page at the root of the output directory. Overrides + /// `enable_index_page` to be true if set. + pub(crate) index_page: Option, + /// An optional path to use as the location of static files. If not set, uses combinations of + /// `../` to reach the documentation root. + pub(crate) static_root_path: Option, + + // Options specific to reading standalone Markdown files + /// Whether to generate a table of contents on the output file when reading a standalone + /// Markdown file. + pub(crate) markdown_no_toc: bool, + /// Additional CSS files to link in pages generated from standalone Markdown files. + pub(crate) markdown_css: Vec, + /// If present, playground URL to use in the "Run" button added to code samples generated from + /// standalone Markdown files. If not present, `playground_url` is used. + pub(crate) markdown_playground_url: Option, + /// Document items that have lower than `pub` visibility. + pub(crate) document_private: bool, + /// Document items that have `doc(hidden)`. + pub(crate) document_hidden: bool, + /// If `true`, generate a JSON file in the crate folder instead of HTML redirection files. + pub(crate) generate_redirect_map: bool, + /// Show the memory layout of types in the docs. + pub(crate) show_type_layout: bool, + pub(crate) unstable_features: rustc_feature::UnstableFeatures, + pub(crate) emit: Vec, + /// If `true`, HTML source pages will generate links for items to their definition. + pub(crate) generate_link_to_definition: bool, + /// Set of function-call locations to include as examples + pub(crate) call_locations: AllCallLocations, + /// If `true`, Context::init will not emit shared files. + pub(crate) no_emit_shared: bool, +} + +#[derive(Copy, Clone, Debug, PartialEq, Eq)] +pub(crate) enum ModuleSorting { + DeclarationOrder, + Alphabetical, +} + +#[derive(Copy, Clone, Debug, PartialEq, Eq)] +pub(crate) enum EmitType { + Unversioned, + Toolchain, + InvocationSpecific, +} + +impl FromStr for EmitType { + type Err = (); + + fn from_str(s: &str) -> Result { + use EmitType::*; + match s { + "unversioned-shared-resources" => Ok(Unversioned), + "toolchain-shared-resources" => Ok(Toolchain), + "invocation-specific" => Ok(InvocationSpecific), + _ => Err(()), + } + } +} + +impl RenderOptions { + pub(crate) fn should_emit_crate(&self) -> bool { + self.emit.is_empty() || self.emit.contains(&EmitType::InvocationSpecific) + } +} + +impl Options { + /// Parses the given command-line for options. If an error message or other early-return has + /// been printed, returns `Err` with the exit code. + pub(crate) fn from_matches( + matches: &getopts::Matches, + args: Vec, + ) -> Result { + let args = &args[1..]; + // Check for unstable options. + nightly_options::check_nightly_options(matches, &opts()); + + if args.is_empty() || matches.opt_present("h") || matches.opt_present("help") { + crate::usage("rustdoc"); + return Err(0); + } else if matches.opt_present("version") { + rustc_driver::version("rustdoc", matches); + return Err(0); + } + + let z_flags = matches.opt_strs("Z"); + if z_flags.iter().any(|x| *x == "help") { + print_flag_list("-Z", config::Z_OPTIONS); + return Err(0); + } + let c_flags = matches.opt_strs("C"); + if c_flags.iter().any(|x| *x == "help") { + print_flag_list("-C", config::CG_OPTIONS); + return Err(0); + } + + let color = config::parse_color(matches); + let config::JsonConfig { json_rendered, json_unused_externs, .. } = + config::parse_json(matches); + let error_format = config::parse_error_format(matches, color, json_rendered); + let diagnostic_width = matches.opt_get("diagnostic-width").unwrap_or_default(); + + let codegen_options = CodegenOptions::build(matches, error_format); + let unstable_opts = UnstableOptions::build(matches, error_format); + + let diag = new_handler(error_format, None, diagnostic_width, &unstable_opts); + + // check for deprecated options + check_deprecated_options(matches, &diag); + + if matches.opt_strs("passes") == ["list"] { + println!("Available passes for running rustdoc:"); + for pass in passes::PASSES { + println!("{:>20} - {}", pass.name, pass.description); + } + println!("\nDefault passes for rustdoc:"); + for p in passes::DEFAULT_PASSES { + print!("{:>20}", p.pass.name); + println_condition(p.condition); + } + + if nightly_options::match_is_nightly_build(matches) { + println!("\nPasses run with `--show-coverage`:"); + for p in passes::COVERAGE_PASSES { + print!("{:>20}", p.pass.name); + println_condition(p.condition); + } + } + + fn println_condition(condition: Condition) { + use Condition::*; + match condition { + Always => println!(), + WhenDocumentPrivate => println!(" (when --document-private-items)"), + WhenNotDocumentPrivate => println!(" (when not --document-private-items)"), + WhenNotDocumentHidden => println!(" (when not --document-hidden-items)"), + } + } + + return Err(0); + } + + let mut emit = Vec::new(); + for list in matches.opt_strs("emit") { + for kind in list.split(',') { + match kind.parse() { + Ok(kind) => emit.push(kind), + Err(()) => { + diag.err(&format!("unrecognized emission type: {}", kind)); + return Err(1); + } + } + } + } + + // check for `--output-format=json` + if !matches!(matches.opt_str("output-format").as_deref(), None | Some("html")) + && !matches.opt_present("show-coverage") + && !nightly_options::is_unstable_enabled(matches) + { + rustc_session::early_error( + error_format, + "the -Z unstable-options flag must be passed to enable --output-format for documentation generation (see https://github.com/rust-lang/rust/issues/76578)", + ); + } + + let to_check = matches.opt_strs("check-theme"); + if !to_check.is_empty() { + let paths = theme::load_css_paths(static_files::themes::LIGHT.as_bytes()); + let mut errors = 0; + + println!("rustdoc: [check-theme] Starting tests! (Ignoring all other arguments)"); + for theme_file in to_check.iter() { + print!(" - Checking \"{}\"...", theme_file); + let (success, differences) = theme::test_theme_against(theme_file, &paths, &diag); + if !differences.is_empty() || !success { + println!(" FAILED"); + errors += 1; + if !differences.is_empty() { + println!("{}", differences.join("\n")); + } + } else { + println!(" OK"); + } + } + if errors != 0 { + return Err(1); + } + return Err(0); + } + + let (lint_opts, describe_lints, lint_cap) = get_cmd_lint_options(matches, error_format); + + let input = PathBuf::from(if describe_lints { + "" // dummy, this won't be used + } else if matches.free.is_empty() { + diag.struct_err("missing file operand").emit(); + return Err(1); + } else if matches.free.len() > 1 { + diag.struct_err("too many file operands").emit(); + return Err(1); + } else { + &matches.free[0] + }); + + let libs = matches + .opt_strs("L") + .iter() + .map(|s| SearchPath::from_cli_opt(s, error_format)) + .collect(); + let externs = parse_externs(matches, &unstable_opts, error_format); + let extern_html_root_urls = match parse_extern_html_roots(matches) { + Ok(ex) => ex, + Err(err) => { + diag.struct_err(err).emit(); + return Err(1); + } + }; + + let default_settings: Vec> = vec![ + matches + .opt_str("default-theme") + .iter() + .flat_map(|theme| { + vec![ + ("use-system-theme".to_string(), "false".to_string()), + ("theme".to_string(), theme.to_string()), + ] + }) + .collect(), + matches + .opt_strs("default-setting") + .iter() + .map(|s| match s.split_once('=') { + None => (s.clone(), "true".to_string()), + Some((k, v)) => (k.to_string(), v.to_string()), + }) + .collect(), + ]; + let default_settings = default_settings + .into_iter() + .flatten() + .map( + // The keys here become part of `data-` attribute names in the generated HTML. The + // browser does a strange mapping when converting them into attributes on the + // `dataset` property on the DOM HTML Node: + // https://developer.mozilla.org/en-US/docs/Web/API/HTMLElement/dataset + // + // The original key values we have are the same as the DOM storage API keys and the + // command line options, so contain `-`. Our Javascript needs to be able to look + // these values up both in `dataset` and in the storage API, so it needs to be able + // to convert the names back and forth. Despite doing this kebab-case to + // StudlyCaps transformation automatically, the JS DOM API does not provide a + // mechanism for doing the just transformation on a string. So we want to avoid + // the StudlyCaps representation in the `dataset` property. + // + // We solve this by replacing all the `-`s with `_`s. We do that here, when we + // generate the `data-` attributes, and in the JS, when we look them up. (See + // `getSettingValue` in `storage.js.`) Converting `-` to `_` is simple in JS. + // + // The values will be HTML-escaped by the default Tera escaping. + |(k, v)| (k.replace('-', "_"), v), + ) + .collect(); + + let test_args = matches.opt_strs("test-args"); + let test_args: Vec = + test_args.iter().flat_map(|s| s.split_whitespace()).map(|s| s.to_string()).collect(); + + let should_test = matches.opt_present("test"); + let no_run = matches.opt_present("no-run"); + + if !should_test && no_run { + diag.err("the `--test` flag must be passed to enable `--no-run`"); + return Err(1); + } + + let out_dir = matches.opt_str("out-dir").map(|s| PathBuf::from(&s)); + let output = matches.opt_str("output").map(|s| PathBuf::from(&s)); + let output = match (out_dir, output) { + (Some(_), Some(_)) => { + diag.struct_err("cannot use both 'out-dir' and 'output' at once").emit(); + return Err(1); + } + (Some(out_dir), None) => out_dir, + (None, Some(output)) => output, + (None, None) => PathBuf::from("doc"), + }; + + let cfgs = matches.opt_strs("cfg"); + let check_cfgs = matches.opt_strs("check-cfg"); + + let extension_css = matches.opt_str("e").map(|s| PathBuf::from(&s)); + + if let Some(ref p) = extension_css { + if !p.is_file() { + diag.struct_err("option --extend-css argument must be a file").emit(); + return Err(1); + } + } + + let mut themes = Vec::new(); + if matches.opt_present("theme") { + let paths = theme::load_css_paths(static_files::themes::LIGHT.as_bytes()); + + for (theme_file, theme_s) in + matches.opt_strs("theme").iter().map(|s| (PathBuf::from(&s), s.to_owned())) + { + if !theme_file.is_file() { + diag.struct_err(&format!("invalid argument: \"{}\"", theme_s)) + .help("arguments to --theme must be files") + .emit(); + return Err(1); + } + if theme_file.extension() != Some(OsStr::new("css")) { + diag.struct_err(&format!("invalid argument: \"{}\"", theme_s)) + .help("arguments to --theme must have a .css extension") + .emit(); + return Err(1); + } + let (success, ret) = theme::test_theme_against(&theme_file, &paths, &diag); + if !success { + diag.struct_err(&format!("error loading theme file: \"{}\"", theme_s)).emit(); + return Err(1); + } else if !ret.is_empty() { + diag.struct_warn(&format!( + "theme file \"{}\" is missing CSS rules from the default theme", + theme_s + )) + .warn("the theme may appear incorrect when loaded") + .help(&format!( + "to see what rules are missing, call `rustdoc --check-theme \"{}\"`", + theme_s + )) + .emit(); + } + themes.push(StylePath { path: theme_file }); + } + } + + let edition = config::parse_crate_edition(matches); + + let mut id_map = html::markdown::IdMap::new(); + let Some(external_html) = ExternalHtml::load( + &matches.opt_strs("html-in-header"), + &matches.opt_strs("html-before-content"), + &matches.opt_strs("html-after-content"), + &matches.opt_strs("markdown-before-content"), + &matches.opt_strs("markdown-after-content"), + nightly_options::match_is_nightly_build(matches), + &diag, + &mut id_map, + edition, + &None, + ) else { + return Err(3); + }; + + match matches.opt_str("r").as_deref() { + Some("rust") | None => {} + Some(s) => { + diag.struct_err(&format!("unknown input format: {}", s)).emit(); + return Err(1); + } + } + + let index_page = matches.opt_str("index-page").map(|s| PathBuf::from(&s)); + if let Some(ref index_page) = index_page { + if !index_page.is_file() { + diag.struct_err("option `--index-page` argument must be a file").emit(); + return Err(1); + } + } + + let target = parse_target_triple(matches, error_format); + + let show_coverage = matches.opt_present("show-coverage"); + + let crate_types = match parse_crate_types_from_list(matches.opt_strs("crate-type")) { + Ok(types) => types, + Err(e) => { + diag.struct_err(&format!("unknown crate type: {}", e)).emit(); + return Err(1); + } + }; + + let output_format = match matches.opt_str("output-format") { + Some(s) => match OutputFormat::try_from(s.as_str()) { + Ok(out_fmt) => { + if !out_fmt.is_json() && show_coverage { + diag.struct_err( + "html output format isn't supported for the --show-coverage option", + ) + .emit(); + return Err(1); + } + out_fmt + } + Err(e) => { + diag.struct_err(&e).emit(); + return Err(1); + } + }, + None => OutputFormat::default(), + }; + let crate_name = matches.opt_str("crate-name"); + let proc_macro_crate = crate_types.contains(&CrateType::ProcMacro); + let playground_url = matches.opt_str("playground-url"); + let maybe_sysroot = matches.opt_str("sysroot").map(PathBuf::from); + let module_sorting = if matches.opt_present("sort-modules-by-appearance") { + ModuleSorting::DeclarationOrder + } else { + ModuleSorting::Alphabetical + }; + let resource_suffix = matches.opt_str("resource-suffix").unwrap_or_default(); + let enable_minification = !matches.opt_present("disable-minification"); + let markdown_no_toc = matches.opt_present("markdown-no-toc"); + let markdown_css = matches.opt_strs("markdown-css"); + let markdown_playground_url = matches.opt_str("markdown-playground-url"); + let crate_version = matches.opt_str("crate-version"); + let enable_index_page = matches.opt_present("enable-index-page") || index_page.is_some(); + let static_root_path = matches.opt_str("static-root-path"); + let test_run_directory = matches.opt_str("test-run-directory").map(PathBuf::from); + let persist_doctests = matches.opt_str("persist-doctests").map(PathBuf::from); + let test_builder = matches.opt_str("test-builder").map(PathBuf::from); + let codegen_options_strs = matches.opt_strs("C"); + let unstable_opts_strs = matches.opt_strs("Z"); + let lib_strs = matches.opt_strs("L"); + let extern_strs = matches.opt_strs("extern"); + let runtool = matches.opt_str("runtool"); + let runtool_args = matches.opt_strs("runtool-arg"); + let enable_per_target_ignores = matches.opt_present("enable-per-target-ignores"); + let document_private = matches.opt_present("document-private-items"); + let document_hidden = matches.opt_present("document-hidden-items"); + let run_check = matches.opt_present("check"); + let generate_redirect_map = matches.opt_present("generate-redirect-map"); + let show_type_layout = matches.opt_present("show-type-layout"); + let nocapture = matches.opt_present("nocapture"); + let generate_link_to_definition = matches.opt_present("generate-link-to-definition"); + let extern_html_root_takes_precedence = + matches.opt_present("extern-html-root-takes-precedence"); + + if generate_link_to_definition && (show_coverage || output_format != OutputFormat::Html) { + diag.struct_err( + "--generate-link-to-definition option can only be used with HTML output format", + ) + .emit(); + return Err(1); + } + + let scrape_examples_options = ScrapeExamplesOptions::new(matches, &diag)?; + let with_examples = matches.opt_strs("with-examples"); + let call_locations = crate::scrape_examples::load_call_locations(with_examples, &diag)?; + + Ok(Options { + input, + proc_macro_crate, + error_format, + diagnostic_width, + libs, + lib_strs, + externs, + extern_strs, + cfgs, + check_cfgs, + codegen_options, + codegen_options_strs, + unstable_opts, + unstable_opts_strs, + target, + edition, + maybe_sysroot, + lint_opts, + describe_lints, + lint_cap, + should_test, + test_args, + show_coverage, + crate_version, + test_run_directory, + persist_doctests, + runtool, + runtool_args, + enable_per_target_ignores, + test_builder, + run_check, + no_run, + nocapture, + render_options: RenderOptions { + output, + external_html, + id_map, + playground_url, + module_sorting, + themes, + extension_css, + extern_html_root_urls, + extern_html_root_takes_precedence, + default_settings, + resource_suffix, + enable_minification, + enable_index_page, + index_page, + static_root_path, + markdown_no_toc, + markdown_css, + markdown_playground_url, + document_private, + document_hidden, + generate_redirect_map, + show_type_layout, + unstable_features: rustc_feature::UnstableFeatures::from_environment( + crate_name.as_deref(), + ), + emit, + generate_link_to_definition, + call_locations, + no_emit_shared: false, + }, + crate_name, + output_format, + json_unused_externs, + scrape_examples_options, + }) + } + + /// Returns `true` if the file given as `self.input` is a Markdown file. + pub(crate) fn markdown_input(&self) -> bool { + self.input.extension().map_or(false, |e| e == "md" || e == "markdown") + } +} + +/// Prints deprecation warnings for deprecated options +fn check_deprecated_options(matches: &getopts::Matches, diag: &rustc_errors::Handler) { + let deprecated_flags = []; + + for &flag in deprecated_flags.iter() { + if matches.opt_present(flag) { + diag.struct_warn(&format!("the `{}` flag is deprecated", flag)) + .note( + "see issue #44136 \ + for more information", + ) + .emit(); + } + } + + let removed_flags = ["plugins", "plugin-path", "no-defaults", "passes", "input-format"]; + + for &flag in removed_flags.iter() { + if matches.opt_present(flag) { + let mut err = diag.struct_warn(&format!("the `{}` flag no longer functions", flag)); + err.note( + "see issue #44136 \ + for more information", + ); + + if flag == "no-defaults" || flag == "passes" { + err.help("you may want to use --document-private-items"); + } else if flag == "plugins" || flag == "plugin-path" { + err.warn("see CVE-2018-1000622"); + } + + err.emit(); + } + } +} + +/// Extracts `--extern-html-root-url` arguments from `matches` and returns a map of crate names to +/// the given URLs. If an `--extern-html-root-url` argument was ill-formed, returns an error +/// describing the issue. +fn parse_extern_html_roots( + matches: &getopts::Matches, +) -> Result, &'static str> { + let mut externs = BTreeMap::new(); + for arg in &matches.opt_strs("extern-html-root-url") { + let (name, url) = + arg.split_once('=').ok_or("--extern-html-root-url must be of the form name=url")?; + externs.insert(name.to_string(), url.to_string()); + } + Ok(externs) +} diff --git a/src/librustdoc/core.rs b/src/librustdoc/core.rs new file mode 100644 index 000000000..c48b25aea --- /dev/null +++ b/src/librustdoc/core.rs @@ -0,0 +1,566 @@ +use rustc_ast::NodeId; +use rustc_data_structures::fx::{FxHashMap, FxHashSet}; +use rustc_data_structures::sync::{self, Lrc}; +use rustc_errors::emitter::{Emitter, EmitterWriter}; +use rustc_errors::json::JsonEmitter; +use rustc_feature::UnstableFeatures; +use rustc_hir::def::{Namespace, Res}; +use rustc_hir::def_id::{DefId, DefIdMap, LocalDefId}; +use rustc_hir::intravisit::{self, Visitor}; +use rustc_hir::{HirId, Path, TraitCandidate}; +use rustc_interface::interface; +use rustc_middle::hir::nested_filter; +use rustc_middle::middle::privacy::AccessLevels; +use rustc_middle::ty::{ParamEnv, Ty, TyCtxt}; +use rustc_resolve as resolve; +use rustc_session::config::{self, CrateType, ErrorOutputType}; +use rustc_session::lint; +use rustc_session::DiagnosticOutput; +use rustc_session::Session; +use rustc_span::symbol::sym; +use rustc_span::{source_map, Span, Symbol}; + +use std::cell::RefCell; +use std::mem; +use std::rc::Rc; +use std::sync::LazyLock; + +use crate::clean::inline::build_external_trait; +use crate::clean::{self, ItemId, TraitWithExtraInfo}; +use crate::config::{Options as RustdocOptions, OutputFormat, RenderOptions}; +use crate::formats::cache::Cache; +use crate::passes::collect_intra_doc_links::PreprocessedMarkdownLink; +use crate::passes::{self, Condition::*}; + +pub(crate) use rustc_session::config::{Input, Options, UnstableOptions}; + +pub(crate) struct ResolverCaches { + pub(crate) markdown_links: Option>>, + pub(crate) doc_link_resolutions: FxHashMap<(Symbol, Namespace, DefId), Option>>, + /// Traits in scope for a given module. + /// See `collect_intra_doc_links::traits_implemented_by` for more details. + pub(crate) traits_in_scope: DefIdMap>, + pub(crate) all_traits: Option>, + pub(crate) all_trait_impls: Option>, + pub(crate) all_macro_rules: FxHashMap>, +} + +pub(crate) struct DocContext<'tcx> { + pub(crate) tcx: TyCtxt<'tcx>, + /// Name resolver. Used for intra-doc links. + /// + /// The `Rc>` wrapping is needed because that is what's returned by + /// [`rustc_interface::Queries::expansion()`]. + // FIXME: see if we can get rid of this RefCell somehow + pub(crate) resolver: Rc>, + pub(crate) resolver_caches: ResolverCaches, + /// Used for normalization. + /// + /// Most of this logic is copied from rustc_lint::late. + pub(crate) param_env: ParamEnv<'tcx>, + /// Later on moved through `clean::Crate` into `cache` + pub(crate) external_traits: Rc>>, + /// Used while populating `external_traits` to ensure we don't process the same trait twice at + /// the same time. + pub(crate) active_extern_traits: FxHashSet, + // The current set of parameter substitutions, + // for expanding type aliases at the HIR level: + /// Table `DefId` of type, lifetime, or const parameter -> substituted type, lifetime, or const + pub(crate) substs: FxHashMap, + /// Table synthetic type parameter for `impl Trait` in argument position -> bounds + pub(crate) impl_trait_bounds: FxHashMap>, + /// Auto-trait or blanket impls processed so far, as `(self_ty, trait_def_id)`. + // FIXME(eddyb) make this a `ty::TraitRef<'tcx>` set. + pub(crate) generated_synthetics: FxHashSet<(Ty<'tcx>, DefId)>, + pub(crate) auto_traits: Vec, + /// The options given to rustdoc that could be relevant to a pass. + pub(crate) render_options: RenderOptions, + /// This same cache is used throughout rustdoc, including in [`crate::html::render`]. + pub(crate) cache: Cache, + /// Used by [`clean::inline`] to tell if an item has already been inlined. + pub(crate) inlined: FxHashSet, + /// Used by `calculate_doc_coverage`. + pub(crate) output_format: OutputFormat, + /// Used by `strip_private`. + pub(crate) show_coverage: bool, +} + +impl<'tcx> DocContext<'tcx> { + pub(crate) fn sess(&self) -> &'tcx Session { + self.tcx.sess + } + + pub(crate) fn with_param_env T>( + &mut self, + def_id: DefId, + f: F, + ) -> T { + let old_param_env = mem::replace(&mut self.param_env, self.tcx.param_env(def_id)); + let ret = f(self); + self.param_env = old_param_env; + ret + } + + pub(crate) fn enter_resolver(&self, f: F) -> R + where + F: FnOnce(&mut resolve::Resolver<'_>) -> R, + { + self.resolver.borrow_mut().access(f) + } + + /// Call the closure with the given parameters set as + /// the substitutions for a type alias' RHS. + pub(crate) fn enter_alias( + &mut self, + substs: FxHashMap, + f: F, + ) -> R + where + F: FnOnce(&mut Self) -> R, + { + let old_substs = mem::replace(&mut self.substs, substs); + let r = f(self); + self.substs = old_substs; + r + } + + /// Like `hir().local_def_id_to_hir_id()`, but skips calling it on fake DefIds. + /// (This avoids a slice-index-out-of-bounds panic.) + pub(crate) fn as_local_hir_id(tcx: TyCtxt<'_>, item_id: ItemId) -> Option { + match item_id { + ItemId::DefId(real_id) => { + real_id.as_local().map(|def_id| tcx.hir().local_def_id_to_hir_id(def_id)) + } + // FIXME: Can this be `Some` for `Auto` or `Blanket`? + _ => None, + } + } + + pub(crate) fn with_all_traits(&mut self, f: impl FnOnce(&mut Self, &[DefId])) { + let all_traits = self.resolver_caches.all_traits.take(); + f(self, all_traits.as_ref().expect("`all_traits` are already borrowed")); + self.resolver_caches.all_traits = all_traits; + } + + pub(crate) fn with_all_trait_impls(&mut self, f: impl FnOnce(&mut Self, &[DefId])) { + let all_trait_impls = self.resolver_caches.all_trait_impls.take(); + f(self, all_trait_impls.as_ref().expect("`all_trait_impls` are already borrowed")); + self.resolver_caches.all_trait_impls = all_trait_impls; + } +} + +/// Creates a new diagnostic `Handler` that can be used to emit warnings and errors. +/// +/// If the given `error_format` is `ErrorOutputType::Json` and no `SourceMap` is given, a new one +/// will be created for the handler. +pub(crate) fn new_handler( + error_format: ErrorOutputType, + source_map: Option>, + diagnostic_width: Option, + unstable_opts: &UnstableOptions, +) -> rustc_errors::Handler { + let fallback_bundle = + rustc_errors::fallback_fluent_bundle(rustc_errors::DEFAULT_LOCALE_RESOURCES, false); + let emitter: Box = match error_format { + ErrorOutputType::HumanReadable(kind) => { + let (short, color_config) = kind.unzip(); + Box::new( + EmitterWriter::stderr( + color_config, + source_map.map(|sm| sm as _), + None, + fallback_bundle, + short, + unstable_opts.teach, + diagnostic_width, + false, + ) + .ui_testing(unstable_opts.ui_testing), + ) + } + ErrorOutputType::Json { pretty, json_rendered } => { + let source_map = source_map.unwrap_or_else(|| { + Lrc::new(source_map::SourceMap::new(source_map::FilePathMapping::empty())) + }); + Box::new( + JsonEmitter::stderr( + None, + source_map, + None, + fallback_bundle, + pretty, + json_rendered, + diagnostic_width, + false, + ) + .ui_testing(unstable_opts.ui_testing), + ) + } + }; + + rustc_errors::Handler::with_emitter_and_flags( + emitter, + unstable_opts.diagnostic_handler_flags(true), + ) +} + +/// Parse, resolve, and typecheck the given crate. +pub(crate) fn create_config( + RustdocOptions { + input, + crate_name, + proc_macro_crate, + error_format, + diagnostic_width, + libs, + externs, + mut cfgs, + check_cfgs, + codegen_options, + unstable_opts, + target, + edition, + maybe_sysroot, + lint_opts, + describe_lints, + lint_cap, + scrape_examples_options, + .. + }: RustdocOptions, +) -> rustc_interface::Config { + // Add the doc cfg into the doc build. + cfgs.push("doc".to_string()); + + let cpath = Some(input.clone()); + let input = Input::File(input); + + // By default, rustdoc ignores all lints. + // Specifically unblock lints relevant to documentation or the lint machinery itself. + let mut lints_to_show = vec![ + // it's unclear whether these should be part of rustdoc directly (#77364) + rustc_lint::builtin::MISSING_DOCS.name.to_string(), + rustc_lint::builtin::INVALID_DOC_ATTRIBUTES.name.to_string(), + // these are definitely not part of rustdoc, but we want to warn on them anyway. + rustc_lint::builtin::RENAMED_AND_REMOVED_LINTS.name.to_string(), + rustc_lint::builtin::UNKNOWN_LINTS.name.to_string(), + rustc_lint::builtin::UNEXPECTED_CFGS.name.to_string(), + // this lint is needed to support `#[expect]` attributes + rustc_lint::builtin::UNFULFILLED_LINT_EXPECTATIONS.name.to_string(), + ]; + lints_to_show.extend(crate::lint::RUSTDOC_LINTS.iter().map(|lint| lint.name.to_string())); + + let (lint_opts, lint_caps) = crate::lint::init_lints(lints_to_show, lint_opts, |lint| { + Some((lint.name_lower(), lint::Allow)) + }); + + let crate_types = + if proc_macro_crate { vec![CrateType::ProcMacro] } else { vec![CrateType::Rlib] }; + let test = scrape_examples_options.map(|opts| opts.scrape_tests).unwrap_or(false); + // plays with error output here! + let sessopts = config::Options { + maybe_sysroot, + search_paths: libs, + crate_types, + lint_opts, + lint_cap, + cg: codegen_options, + externs, + target_triple: target, + unstable_features: UnstableFeatures::from_environment(crate_name.as_deref()), + actually_rustdoc: true, + unstable_opts, + error_format, + diagnostic_width, + edition, + describe_lints, + crate_name, + test, + ..Options::default() + }; + + interface::Config { + opts: sessopts, + crate_cfg: interface::parse_cfgspecs(cfgs), + crate_check_cfg: interface::parse_check_cfg(check_cfgs), + input, + input_path: cpath, + output_file: None, + output_dir: None, + file_loader: None, + diagnostic_output: DiagnosticOutput::Default, + lint_caps, + parse_sess_created: None, + register_lints: Some(Box::new(crate::lint::register_lints)), + override_queries: Some(|_sess, providers, _external_providers| { + // Most lints will require typechecking, so just don't run them. + providers.lint_mod = |_, _| {}; + // Prevent `rustc_typeck::check_crate` from calling `typeck` on all bodies. + providers.typeck_item_bodies = |_, _| {}; + // hack so that `used_trait_imports` won't try to call typeck + providers.used_trait_imports = |_, _| { + static EMPTY_SET: LazyLock> = + LazyLock::new(FxHashSet::default); + &EMPTY_SET + }; + // In case typeck does end up being called, don't ICE in case there were name resolution errors + providers.typeck = move |tcx, def_id| { + // Closures' tables come from their outermost function, + // as they are part of the same "inference environment". + // This avoids emitting errors for the parent twice (see similar code in `typeck_with_fallback`) + let typeck_root_def_id = tcx.typeck_root_def_id(def_id.to_def_id()).expect_local(); + if typeck_root_def_id != def_id { + return tcx.typeck(typeck_root_def_id); + } + + let hir = tcx.hir(); + let body = hir.body(hir.body_owned_by(def_id)); + debug!("visiting body for {:?}", def_id); + EmitIgnoredResolutionErrors::new(tcx).visit_body(body); + (rustc_interface::DEFAULT_QUERY_PROVIDERS.typeck)(tcx, def_id) + }; + }), + make_codegen_backend: None, + registry: rustc_driver::diagnostics_registry(), + } +} + +pub(crate) fn run_global_ctxt( + tcx: TyCtxt<'_>, + resolver: Rc>, + resolver_caches: ResolverCaches, + show_coverage: bool, + render_options: RenderOptions, + output_format: OutputFormat, +) -> (clean::Crate, RenderOptions, Cache) { + // Certain queries assume that some checks were run elsewhere + // (see https://github.com/rust-lang/rust/pull/73566#issuecomment-656954425), + // so type-check everything other than function bodies in this crate before running lints. + + // NOTE: this does not call `tcx.analysis()` so that we won't + // typeck function bodies or run the default rustc lints. + // (see `override_queries` in the `config`) + + // HACK(jynelson) this calls an _extremely_ limited subset of `typeck` + // and might break if queries change their assumptions in the future. + + // NOTE: This is copy/pasted from typeck/lib.rs and should be kept in sync with those changes. + tcx.sess.time("item_types_checking", || { + tcx.hir().for_each_module(|module| tcx.ensure().check_mod_item_types(module)) + }); + tcx.sess.abort_if_errors(); + tcx.sess.time("missing_docs", || { + rustc_lint::check_crate(tcx, rustc_lint::builtin::MissingDoc::new); + }); + tcx.sess.time("check_mod_attrs", || { + tcx.hir().for_each_module(|module| tcx.ensure().check_mod_attrs(module)) + }); + rustc_passes::stability::check_unused_or_stable_features(tcx); + + let auto_traits = resolver_caches + .all_traits + .as_ref() + .expect("`all_traits` are already borrowed") + .iter() + .copied() + .filter(|&trait_def_id| tcx.trait_is_auto(trait_def_id)) + .collect(); + let access_levels = AccessLevels { + map: tcx.privacy_access_levels(()).map.iter().map(|(k, v)| (k.to_def_id(), *v)).collect(), + }; + + let mut ctxt = DocContext { + tcx, + resolver, + resolver_caches, + param_env: ParamEnv::empty(), + external_traits: Default::default(), + active_extern_traits: Default::default(), + substs: Default::default(), + impl_trait_bounds: Default::default(), + generated_synthetics: Default::default(), + auto_traits, + cache: Cache::new(access_levels, render_options.document_private), + inlined: FxHashSet::default(), + output_format, + render_options, + show_coverage, + }; + + // Small hack to force the Sized trait to be present. + // + // Note that in case of `#![no_core]`, the trait is not available. + if let Some(sized_trait_did) = ctxt.tcx.lang_items().sized_trait() { + let sized_trait = build_external_trait(&mut ctxt, sized_trait_did); + ctxt.external_traits + .borrow_mut() + .insert(sized_trait_did, TraitWithExtraInfo { trait_: sized_trait, is_notable: false }); + } + + debug!("crate: {:?}", tcx.hir().krate()); + + let mut krate = tcx.sess.time("clean_crate", || clean::krate(&mut ctxt)); + + if krate.module.doc_value().map(|d| d.is_empty()).unwrap_or(true) { + let help = format!( + "The following guide may be of use:\n\ + {}/rustdoc/how-to-write-documentation.html", + crate::DOC_RUST_LANG_ORG_CHANNEL + ); + tcx.struct_lint_node( + crate::lint::MISSING_CRATE_LEVEL_DOCS, + DocContext::as_local_hir_id(tcx, krate.module.item_id).unwrap(), + |lint| { + let mut diag = + lint.build("no documentation found for this crate's top-level module"); + diag.help(&help); + diag.emit(); + }, + ); + } + + fn report_deprecated_attr(name: &str, diag: &rustc_errors::Handler, sp: Span) { + let mut msg = + diag.struct_span_warn(sp, &format!("the `#![doc({})]` attribute is deprecated", name)); + msg.note( + "see issue #44136 \ + for more information", + ); + + if name == "no_default_passes" { + msg.help("`#![doc(no_default_passes)]` no longer functions; you may want to use `#![doc(document_private_items)]`"); + } else if name.starts_with("passes") { + msg.help("`#![doc(passes = \"...\")]` no longer functions; you may want to use `#![doc(document_private_items)]`"); + } else if name.starts_with("plugins") { + msg.warn("`#![doc(plugins = \"...\")]` no longer functions; see CVE-2018-1000622 "); + } + + msg.emit(); + } + + // Process all of the crate attributes, extracting plugin metadata along + // with the passes which we are supposed to run. + for attr in krate.module.attrs.lists(sym::doc) { + let diag = ctxt.sess().diagnostic(); + + let name = attr.name_or_empty(); + // `plugins = "..."`, `no_default_passes`, and `passes = "..."` have no effect + if attr.is_word() && name == sym::no_default_passes { + report_deprecated_attr("no_default_passes", diag, attr.span()); + } else if attr.value_str().is_some() { + match name { + sym::passes => { + report_deprecated_attr("passes = \"...\"", diag, attr.span()); + } + sym::plugins => { + report_deprecated_attr("plugins = \"...\"", diag, attr.span()); + } + _ => (), + } + } + + if attr.is_word() && name == sym::document_private_items { + ctxt.render_options.document_private = true; + } + } + + info!("Executing passes"); + + for p in passes::defaults(show_coverage) { + let run = match p.condition { + Always => true, + WhenDocumentPrivate => ctxt.render_options.document_private, + WhenNotDocumentPrivate => !ctxt.render_options.document_private, + WhenNotDocumentHidden => !ctxt.render_options.document_hidden, + }; + if run { + debug!("running pass {}", p.pass.name); + krate = tcx.sess.time(p.pass.name, || (p.pass.run)(krate, &mut ctxt)); + } + } + + tcx.sess.time("check_lint_expectations", || tcx.check_expectations(Some(sym::rustdoc))); + + if tcx.sess.diagnostic().has_errors_or_lint_errors().is_some() { + rustc_errors::FatalError.raise(); + } + + krate = tcx.sess.time("create_format_cache", || Cache::populate(&mut ctxt, krate)); + + (krate, ctxt.render_options, ctxt.cache) +} + +/// Due to , +/// the name resolution pass may find errors that are never emitted. +/// If typeck is called after this happens, then we'll get an ICE: +/// 'Res::Error found but not reported'. To avoid this, emit the errors now. +struct EmitIgnoredResolutionErrors<'tcx> { + tcx: TyCtxt<'tcx>, +} + +impl<'tcx> EmitIgnoredResolutionErrors<'tcx> { + fn new(tcx: TyCtxt<'tcx>) -> Self { + Self { tcx } + } +} + +impl<'tcx> Visitor<'tcx> for EmitIgnoredResolutionErrors<'tcx> { + type NestedFilter = nested_filter::OnlyBodies; + + fn nested_visit_map(&mut self) -> Self::Map { + // We need to recurse into nested closures, + // since those will fallback to the parent for type checking. + self.tcx.hir() + } + + fn visit_path(&mut self, path: &'tcx Path<'_>, _id: HirId) { + debug!("visiting path {:?}", path); + if path.res == Res::Err { + // We have less context here than in rustc_resolve, + // so we can only emit the name and span. + // However we can give a hint that rustc_resolve will have more info. + let label = format!( + "could not resolve path `{}`", + path.segments + .iter() + .map(|segment| segment.ident.as_str()) + .intersperse("::") + .collect::() + ); + let mut err = rustc_errors::struct_span_err!( + self.tcx.sess, + path.span, + E0433, + "failed to resolve: {}", + label + ); + err.span_label(path.span, label); + err.note("this error was originally ignored because you are running `rustdoc`"); + err.note("try running again with `rustc` or `cargo check` and you may get a more detailed error"); + err.emit(); + } + // We could have an outer resolution that succeeded, + // but with generic parameters that failed. + // Recurse into the segments so we catch those too. + intravisit::walk_path(self, path); + } +} + +/// `DefId` or parameter index (`ty::ParamTy.index`) of a synthetic type parameter +/// for `impl Trait` in argument position. +#[derive(Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord)] +pub(crate) enum ImplTraitParam { + DefId(DefId), + ParamIndex(u32), +} + +impl From for ImplTraitParam { + fn from(did: DefId) -> Self { + ImplTraitParam::DefId(did) + } +} + +impl From for ImplTraitParam { + fn from(idx: u32) -> Self { + ImplTraitParam::ParamIndex(idx) + } +} diff --git a/src/librustdoc/docfs.rs b/src/librustdoc/docfs.rs new file mode 100644 index 000000000..be066bdaf --- /dev/null +++ b/src/librustdoc/docfs.rs @@ -0,0 +1,78 @@ +//! Rustdoc's FileSystem abstraction module. +//! +//! On Windows this indirects IO into threads to work around performance issues +//! with Defender (and other similar virus scanners that do blocking operations). +//! On other platforms this is a thin shim to fs. +//! +//! Only calls needed to permit this workaround have been abstracted: thus +//! fs::read is still done directly via the fs module; if in future rustdoc +//! needs to read-after-write from a file, then it would be added to this +//! abstraction. + +use std::fs; +use std::io; +use std::path::{Path, PathBuf}; +use std::string::ToString; +use std::sync::mpsc::Sender; + +pub(crate) trait PathError { + fn new>(e: S, path: P) -> Self + where + S: ToString + Sized; +} + +pub(crate) struct DocFS { + sync_only: bool, + errors: Option>, +} + +impl DocFS { + pub(crate) fn new(errors: Sender) -> DocFS { + DocFS { sync_only: false, errors: Some(errors) } + } + + pub(crate) fn set_sync_only(&mut self, sync_only: bool) { + self.sync_only = sync_only; + } + + pub(crate) fn close(&mut self) { + self.errors = None; + } + + pub(crate) fn create_dir_all>(&self, path: P) -> io::Result<()> { + // For now, dir creation isn't a huge time consideration, do it + // synchronously, which avoids needing ordering between write() actions + // and directory creation. + fs::create_dir_all(path) + } + + pub(crate) fn write( + &self, + path: PathBuf, + contents: impl 'static + Send + AsRef<[u8]>, + ) -> Result<(), E> + where + E: PathError, + { + #[cfg(windows)] + if !self.sync_only { + // A possible future enhancement after more detailed profiling would + // be to create the file sync so errors are reported eagerly. + let sender = self.errors.clone().expect("can't write after closing"); + rayon::spawn(move || { + fs::write(&path, contents).unwrap_or_else(|e| { + sender.send(format!("\"{}\": {}", path.display(), e)).unwrap_or_else(|_| { + panic!("failed to send error on \"{}\"", path.display()) + }) + }); + }); + } else { + fs::write(&path, contents).map_err(|e| E::new(e, path))?; + } + + #[cfg(not(windows))] + fs::write(&path, contents).map_err(|e| E::new(e, path))?; + + Ok(()) + } +} diff --git a/src/librustdoc/doctest.rs b/src/librustdoc/doctest.rs new file mode 100644 index 000000000..35964e3ba --- /dev/null +++ b/src/librustdoc/doctest.rs @@ -0,0 +1,1311 @@ +use rustc_ast as ast; +use rustc_data_structures::fx::{FxHashMap, FxHashSet}; +use rustc_data_structures::sync::Lrc; +use rustc_errors::{ColorConfig, ErrorGuaranteed, FatalError}; +use rustc_hir as hir; +use rustc_hir::def_id::LOCAL_CRATE; +use rustc_hir::intravisit; +use rustc_hir::{HirId, CRATE_HIR_ID}; +use rustc_interface::interface; +use rustc_middle::hir::map::Map; +use rustc_middle::hir::nested_filter; +use rustc_middle::ty::TyCtxt; +use rustc_parse::maybe_new_parser_from_source_str; +use rustc_parse::parser::attr::InnerAttrPolicy; +use rustc_session::config::{self, CrateType, ErrorOutputType}; +use rustc_session::parse::ParseSess; +use rustc_session::{lint, DiagnosticOutput, Session}; +use rustc_span::edition::Edition; +use rustc_span::source_map::SourceMap; +use rustc_span::symbol::sym; +use rustc_span::Symbol; +use rustc_span::{BytePos, FileName, Pos, Span, DUMMY_SP}; +use rustc_target::spec::TargetTriple; +use tempfile::Builder as TempFileBuilder; + +use std::env; +use std::io::{self, Write}; +use std::panic; +use std::path::PathBuf; +use std::process::{self, Command, Stdio}; +use std::str; +use std::sync::atomic::{AtomicUsize, Ordering}; +use std::sync::{Arc, Mutex}; + +use crate::clean::{types::AttributesExt, Attributes}; +use crate::config::Options as RustdocOptions; +use crate::html::markdown::{self, ErrorCodes, Ignore, LangString}; +use crate::lint::init_lints; +use crate::passes::span_of_attrs; + +/// Options that apply to all doctests in a crate or Markdown file (for `rustdoc foo.md`). +#[derive(Clone, Default)] +pub(crate) struct GlobalTestOptions { + /// Whether to disable the default `extern crate my_crate;` when creating doctests. + pub(crate) no_crate_inject: bool, + /// Additional crate-level attributes to add to doctests. + pub(crate) attrs: Vec, +} + +pub(crate) fn run(options: RustdocOptions) -> Result<(), ErrorGuaranteed> { + let input = config::Input::File(options.input.clone()); + + let invalid_codeblock_attributes_name = crate::lint::INVALID_CODEBLOCK_ATTRIBUTES.name; + + // See core::create_config for what's going on here. + let allowed_lints = vec![ + invalid_codeblock_attributes_name.to_owned(), + lint::builtin::UNKNOWN_LINTS.name.to_owned(), + lint::builtin::RENAMED_AND_REMOVED_LINTS.name.to_owned(), + ]; + + let (lint_opts, lint_caps) = init_lints(allowed_lints, options.lint_opts.clone(), |lint| { + if lint.name == invalid_codeblock_attributes_name { + None + } else { + Some((lint.name_lower(), lint::Allow)) + } + }); + + debug!(?lint_opts); + + let crate_types = + if options.proc_macro_crate { vec![CrateType::ProcMacro] } else { vec![CrateType::Rlib] }; + + let sessopts = config::Options { + maybe_sysroot: options.maybe_sysroot.clone(), + search_paths: options.libs.clone(), + crate_types, + lint_opts, + lint_cap: Some(options.lint_cap.unwrap_or(lint::Forbid)), + cg: options.codegen_options.clone(), + externs: options.externs.clone(), + unstable_features: options.render_options.unstable_features, + actually_rustdoc: true, + edition: options.edition, + target_triple: options.target.clone(), + crate_name: options.crate_name.clone(), + ..config::Options::default() + }; + + let mut cfgs = options.cfgs.clone(); + cfgs.push("doc".to_owned()); + cfgs.push("doctest".to_owned()); + let config = interface::Config { + opts: sessopts, + crate_cfg: interface::parse_cfgspecs(cfgs), + crate_check_cfg: interface::parse_check_cfg(options.check_cfgs.clone()), + input, + input_path: None, + output_file: None, + output_dir: None, + file_loader: None, + diagnostic_output: DiagnosticOutput::Default, + lint_caps, + parse_sess_created: None, + register_lints: Some(Box::new(crate::lint::register_lints)), + override_queries: None, + make_codegen_backend: None, + registry: rustc_driver::diagnostics_registry(), + }; + + let test_args = options.test_args.clone(); + let nocapture = options.nocapture; + let externs = options.externs.clone(); + let json_unused_externs = options.json_unused_externs; + + let (tests, unused_extern_reports, compiling_test_count) = + interface::run_compiler(config, |compiler| { + compiler.enter(|queries| { + let mut global_ctxt = queries.global_ctxt()?.take(); + + let collector = global_ctxt.enter(|tcx| { + let crate_attrs = tcx.hir().attrs(CRATE_HIR_ID); + + let opts = scrape_test_config(crate_attrs); + let enable_per_target_ignores = options.enable_per_target_ignores; + let mut collector = Collector::new( + tcx.crate_name(LOCAL_CRATE), + options, + false, + opts, + Some(compiler.session().parse_sess.clone_source_map()), + None, + enable_per_target_ignores, + ); + + let mut hir_collector = HirCollector { + sess: compiler.session(), + collector: &mut collector, + map: tcx.hir(), + codes: ErrorCodes::from( + compiler.session().opts.unstable_features.is_nightly_build(), + ), + tcx, + }; + hir_collector.visit_testable( + "".to_string(), + CRATE_HIR_ID, + tcx.hir().span(CRATE_HIR_ID), + |this| tcx.hir().walk_toplevel_module(this), + ); + + collector + }); + if compiler.session().diagnostic().has_errors_or_lint_errors().is_some() { + FatalError.raise(); + } + + let unused_extern_reports = collector.unused_extern_reports.clone(); + let compiling_test_count = collector.compiling_test_count.load(Ordering::SeqCst); + let ret: Result<_, ErrorGuaranteed> = + Ok((collector.tests, unused_extern_reports, compiling_test_count)); + ret + }) + })?; + + run_tests(test_args, nocapture, tests); + + // Collect and warn about unused externs, but only if we've gotten + // reports for each doctest + if json_unused_externs.is_enabled() { + let unused_extern_reports: Vec<_> = + std::mem::take(&mut unused_extern_reports.lock().unwrap()); + if unused_extern_reports.len() == compiling_test_count { + let extern_names = externs.iter().map(|(name, _)| name).collect::>(); + let mut unused_extern_names = unused_extern_reports + .iter() + .map(|uexts| uexts.unused_extern_names.iter().collect::>()) + .fold(extern_names, |uextsa, uextsb| { + uextsa.intersection(&uextsb).copied().collect::>() + }) + .iter() + .map(|v| (*v).clone()) + .collect::>(); + unused_extern_names.sort(); + // Take the most severe lint level + let lint_level = unused_extern_reports + .iter() + .map(|uexts| uexts.lint_level.as_str()) + .max_by_key(|v| match *v { + "warn" => 1, + "deny" => 2, + "forbid" => 3, + // The allow lint level is not expected, + // as if allow is specified, no message + // is to be emitted. + v => unreachable!("Invalid lint level '{}'", v), + }) + .unwrap_or("warn") + .to_string(); + let uext = UnusedExterns { lint_level, unused_extern_names }; + let unused_extern_json = serde_json::to_string(&uext).unwrap(); + eprintln!("{unused_extern_json}"); + } + } + + Ok(()) +} + +pub(crate) fn run_tests( + mut test_args: Vec, + nocapture: bool, + tests: Vec, +) { + test_args.insert(0, "rustdoctest".to_string()); + if nocapture { + test_args.push("--nocapture".to_string()); + } + test::test_main(&test_args, tests, None); +} + +// Look for `#![doc(test(no_crate_inject))]`, used by crates in the std facade. +fn scrape_test_config(attrs: &[ast::Attribute]) -> GlobalTestOptions { + use rustc_ast_pretty::pprust; + + let mut opts = GlobalTestOptions { no_crate_inject: false, attrs: Vec::new() }; + + let test_attrs: Vec<_> = attrs + .iter() + .filter(|a| a.has_name(sym::doc)) + .flat_map(|a| a.meta_item_list().unwrap_or_default()) + .filter(|a| a.has_name(sym::test)) + .collect(); + let attrs = test_attrs.iter().flat_map(|a| a.meta_item_list().unwrap_or(&[])); + + for attr in attrs { + if attr.has_name(sym::no_crate_inject) { + opts.no_crate_inject = true; + } + if attr.has_name(sym::attr) { + if let Some(l) = attr.meta_item_list() { + for item in l { + opts.attrs.push(pprust::meta_list_item_to_string(item)); + } + } + } + } + + opts +} + +/// Documentation test failure modes. +enum TestFailure { + /// The test failed to compile. + CompileError, + /// The test is marked `compile_fail` but compiled successfully. + UnexpectedCompilePass, + /// The test failed to compile (as expected) but the compiler output did not contain all + /// expected error codes. + MissingErrorCodes(Vec), + /// The test binary was unable to be executed. + ExecutionError(io::Error), + /// The test binary exited with a non-zero exit code. + /// + /// This typically means an assertion in the test failed or another form of panic occurred. + ExecutionFailure(process::Output), + /// The test is marked `should_panic` but the test binary executed successfully. + UnexpectedRunPass, +} + +enum DirState { + Temp(tempfile::TempDir), + Perm(PathBuf), +} + +impl DirState { + fn path(&self) -> &std::path::Path { + match self { + DirState::Temp(t) => t.path(), + DirState::Perm(p) => p.as_path(), + } + } +} + +// NOTE: Keep this in sync with the equivalent structs in rustc +// and cargo. +// We could unify this struct the one in rustc but they have different +// ownership semantics, so doing so would create wasteful allocations. +#[derive(serde::Serialize, serde::Deserialize)] +struct UnusedExterns { + /// Lint level of the unused_crate_dependencies lint + lint_level: String, + /// List of unused externs by their names. + unused_extern_names: Vec, +} + +fn run_test( + test: &str, + crate_name: &str, + line: usize, + rustdoc_options: RustdocOptions, + mut lang_string: LangString, + no_run: bool, + runtool: Option, + runtool_args: Vec, + target: TargetTriple, + opts: &GlobalTestOptions, + edition: Edition, + outdir: DirState, + path: PathBuf, + test_id: &str, + report_unused_externs: impl Fn(UnusedExterns), +) -> Result<(), TestFailure> { + let (test, line_offset, supports_color) = + make_test(test, Some(crate_name), lang_string.test_harness, opts, edition, Some(test_id)); + + let output_file = outdir.path().join("rust_out"); + + let rustc_binary = rustdoc_options + .test_builder + .as_deref() + .unwrap_or_else(|| rustc_interface::util::rustc_path().expect("found rustc")); + let mut compiler = Command::new(&rustc_binary); + compiler.arg("--crate-type").arg("bin"); + for cfg in &rustdoc_options.cfgs { + compiler.arg("--cfg").arg(&cfg); + } + if !rustdoc_options.check_cfgs.is_empty() { + compiler.arg("-Z").arg("unstable-options"); + for check_cfg in &rustdoc_options.check_cfgs { + compiler.arg("--check-cfg").arg(&check_cfg); + } + } + if let Some(sysroot) = rustdoc_options.maybe_sysroot { + compiler.arg("--sysroot").arg(sysroot); + } + compiler.arg("--edition").arg(&edition.to_string()); + compiler.env("UNSTABLE_RUSTDOC_TEST_PATH", path); + compiler.env("UNSTABLE_RUSTDOC_TEST_LINE", format!("{}", line as isize - line_offset as isize)); + compiler.arg("-o").arg(&output_file); + if lang_string.test_harness { + compiler.arg("--test"); + } + if rustdoc_options.json_unused_externs.is_enabled() && !lang_string.compile_fail { + compiler.arg("--error-format=json"); + compiler.arg("--json").arg("unused-externs"); + compiler.arg("-Z").arg("unstable-options"); + compiler.arg("-W").arg("unused_crate_dependencies"); + } + for lib_str in &rustdoc_options.lib_strs { + compiler.arg("-L").arg(&lib_str); + } + for extern_str in &rustdoc_options.extern_strs { + compiler.arg("--extern").arg(&extern_str); + } + compiler.arg("-Ccodegen-units=1"); + for codegen_options_str in &rustdoc_options.codegen_options_strs { + compiler.arg("-C").arg(&codegen_options_str); + } + for unstable_option_str in &rustdoc_options.unstable_opts_strs { + compiler.arg("-Z").arg(&unstable_option_str); + } + if no_run && !lang_string.compile_fail && rustdoc_options.persist_doctests.is_none() { + compiler.arg("--emit=metadata"); + } + compiler.arg("--target").arg(match target { + TargetTriple::TargetTriple(s) => s, + TargetTriple::TargetJson { path_for_rustdoc, .. } => { + path_for_rustdoc.to_str().expect("target path must be valid unicode").to_string() + } + }); + if let ErrorOutputType::HumanReadable(kind) = rustdoc_options.error_format { + let (short, color_config) = kind.unzip(); + + if short { + compiler.arg("--error-format").arg("short"); + } + + match color_config { + ColorConfig::Never => { + compiler.arg("--color").arg("never"); + } + ColorConfig::Always => { + compiler.arg("--color").arg("always"); + } + ColorConfig::Auto => { + compiler.arg("--color").arg(if supports_color { "always" } else { "never" }); + } + } + } + + compiler.arg("-"); + compiler.stdin(Stdio::piped()); + compiler.stderr(Stdio::piped()); + + let mut child = compiler.spawn().expect("Failed to spawn rustc process"); + { + let stdin = child.stdin.as_mut().expect("Failed to open stdin"); + stdin.write_all(test.as_bytes()).expect("could write out test sources"); + } + let output = child.wait_with_output().expect("Failed to read stdout"); + + struct Bomb<'a>(&'a str); + impl Drop for Bomb<'_> { + fn drop(&mut self) { + eprint!("{}", self.0); + } + } + let mut out = str::from_utf8(&output.stderr) + .unwrap() + .lines() + .filter(|l| { + if let Ok(uext) = serde_json::from_str::(l) { + report_unused_externs(uext); + false + } else { + true + } + }) + .intersperse_with(|| "\n") + .collect::(); + + // Add a \n to the end to properly terminate the last line, + // but only if there was output to be printed + if !out.is_empty() { + out.push('\n'); + } + + let _bomb = Bomb(&out); + match (output.status.success(), lang_string.compile_fail) { + (true, true) => { + return Err(TestFailure::UnexpectedCompilePass); + } + (true, false) => {} + (false, true) => { + if !lang_string.error_codes.is_empty() { + // We used to check if the output contained "error[{}]: " but since we added the + // colored output, we can't anymore because of the color escape characters before + // the ":". + lang_string.error_codes.retain(|err| !out.contains(&format!("error[{err}]"))); + + if !lang_string.error_codes.is_empty() { + return Err(TestFailure::MissingErrorCodes(lang_string.error_codes)); + } + } + } + (false, false) => { + return Err(TestFailure::CompileError); + } + } + + if no_run { + return Ok(()); + } + + // Run the code! + let mut cmd; + + if let Some(tool) = runtool { + cmd = Command::new(tool); + cmd.args(runtool_args); + cmd.arg(output_file); + } else { + cmd = Command::new(output_file); + } + if let Some(run_directory) = rustdoc_options.test_run_directory { + cmd.current_dir(run_directory); + } + + let result = if rustdoc_options.nocapture { + cmd.status().map(|status| process::Output { + status, + stdout: Vec::new(), + stderr: Vec::new(), + }) + } else { + cmd.output() + }; + match result { + Err(e) => return Err(TestFailure::ExecutionError(e)), + Ok(out) => { + if lang_string.should_panic && out.status.success() { + return Err(TestFailure::UnexpectedRunPass); + } else if !lang_string.should_panic && !out.status.success() { + return Err(TestFailure::ExecutionFailure(out)); + } + } + } + + Ok(()) +} + +/// Transforms a test into code that can be compiled into a Rust binary, and returns the number of +/// lines before the test code begins as well as if the output stream supports colors or not. +pub(crate) fn make_test( + s: &str, + crate_name: Option<&str>, + dont_insert_main: bool, + opts: &GlobalTestOptions, + edition: Edition, + test_id: Option<&str>, +) -> (String, usize, bool) { + let (crate_attrs, everything_else, crates) = partition_source(s, edition); + let everything_else = everything_else.trim(); + let mut line_offset = 0; + let mut prog = String::new(); + let mut supports_color = false; + + if opts.attrs.is_empty() { + // If there aren't any attributes supplied by #![doc(test(attr(...)))], then allow some + // lints that are commonly triggered in doctests. The crate-level test attributes are + // commonly used to make tests fail in case they trigger warnings, so having this there in + // that case may cause some tests to pass when they shouldn't have. + prog.push_str("#![allow(unused)]\n"); + line_offset += 1; + } + + // Next, any attributes that came from the crate root via #![doc(test(attr(...)))]. + for attr in &opts.attrs { + prog.push_str(&format!("#![{attr}]\n")); + line_offset += 1; + } + + // Now push any outer attributes from the example, assuming they + // are intended to be crate attributes. + prog.push_str(&crate_attrs); + prog.push_str(&crates); + + // Uses librustc_ast to parse the doctest and find if there's a main fn and the extern + // crate already is included. + let result = rustc_driver::catch_fatal_errors(|| { + rustc_span::create_session_if_not_set_then(edition, |_| { + use rustc_errors::emitter::{Emitter, EmitterWriter}; + use rustc_errors::Handler; + use rustc_parse::parser::ForceCollect; + use rustc_span::source_map::FilePathMapping; + + let filename = FileName::anon_source_code(s); + let source = crates + everything_else; + + // Any errors in parsing should also appear when the doctest is compiled for real, so just + // send all the errors that librustc_ast emits directly into a `Sink` instead of stderr. + let sm = Lrc::new(SourceMap::new(FilePathMapping::empty())); + let fallback_bundle = + rustc_errors::fallback_fluent_bundle(rustc_errors::DEFAULT_LOCALE_RESOURCES, false); + supports_color = EmitterWriter::stderr( + ColorConfig::Auto, + None, + None, + fallback_bundle.clone(), + false, + false, + Some(80), + false, + ) + .supports_color(); + + let emitter = EmitterWriter::new( + Box::new(io::sink()), + None, + None, + fallback_bundle, + false, + false, + false, + None, + false, + ); + + // FIXME(misdreavus): pass `-Z treat-err-as-bug` to the doctest parser + let handler = Handler::with_emitter(false, None, Box::new(emitter)); + let sess = ParseSess::with_span_handler(handler, sm); + + let mut found_main = false; + let mut found_extern_crate = crate_name.is_none(); + let mut found_macro = false; + + let mut parser = match maybe_new_parser_from_source_str(&sess, filename, source) { + Ok(p) => p, + Err(errs) => { + drop(errs); + return (found_main, found_extern_crate, found_macro); + } + }; + + loop { + match parser.parse_item(ForceCollect::No) { + Ok(Some(item)) => { + if !found_main { + if let ast::ItemKind::Fn(..) = item.kind { + if item.ident.name == sym::main { + found_main = true; + } + } + } + + if !found_extern_crate { + if let ast::ItemKind::ExternCrate(original) = item.kind { + // This code will never be reached if `crate_name` is none because + // `found_extern_crate` is initialized to `true` if it is none. + let crate_name = crate_name.unwrap(); + + match original { + Some(name) => found_extern_crate = name.as_str() == crate_name, + None => found_extern_crate = item.ident.as_str() == crate_name, + } + } + } + + if !found_macro { + if let ast::ItemKind::MacCall(..) = item.kind { + found_macro = true; + } + } + + if found_main && found_extern_crate { + break; + } + } + Ok(None) => break, + Err(e) => { + e.cancel(); + break; + } + } + + // The supplied slice is only used for diagnostics, + // which are swallowed here anyway. + parser.maybe_consume_incorrect_semicolon(&[]); + } + + // Reset errors so that they won't be reported as compiler bugs when dropping the + // handler. Any errors in the tests will be reported when the test file is compiled, + // Note that we still need to cancel the errors above otherwise `DiagnosticBuilder` + // will panic on drop. + sess.span_diagnostic.reset_err_count(); + + (found_main, found_extern_crate, found_macro) + }) + }); + let Ok((already_has_main, already_has_extern_crate, found_macro)) = result + else { + // If the parser panicked due to a fatal error, pass the test code through unchanged. + // The error will be reported during compilation. + return (s.to_owned(), 0, false); + }; + + // If a doctest's `fn main` is being masked by a wrapper macro, the parsing loop above won't + // see it. In that case, run the old text-based scan to see if they at least have a main + // function written inside a macro invocation. See + // https://github.com/rust-lang/rust/issues/56898 + let already_has_main = if found_macro && !already_has_main { + s.lines() + .map(|line| { + let comment = line.find("//"); + if let Some(comment_begins) = comment { &line[0..comment_begins] } else { line } + }) + .any(|code| code.contains("fn main")) + } else { + already_has_main + }; + + // Don't inject `extern crate std` because it's already injected by the + // compiler. + if !already_has_extern_crate && !opts.no_crate_inject && crate_name != Some("std") { + if let Some(crate_name) = crate_name { + // Don't inject `extern crate` if the crate is never used. + // NOTE: this is terribly inaccurate because it doesn't actually + // parse the source, but only has false positives, not false + // negatives. + if s.contains(crate_name) { + prog.push_str(&format!("extern crate r#{crate_name};\n")); + line_offset += 1; + } + } + } + + // FIXME: This code cannot yet handle no_std test cases yet + if dont_insert_main || already_has_main || prog.contains("![no_std]") { + prog.push_str(everything_else); + } else { + let returns_result = everything_else.trim_end().ends_with("(())"); + // Give each doctest main function a unique name. + // This is for example needed for the tooling around `-C instrument-coverage`. + let inner_fn_name = if let Some(test_id) = test_id { + format!("_doctest_main_{test_id}") + } else { + "_inner".into() + }; + let inner_attr = if test_id.is_some() { "#[allow(non_snake_case)] " } else { "" }; + let (main_pre, main_post) = if returns_result { + ( + format!( + "fn main() {{ {inner_attr}fn {inner_fn_name}() -> Result<(), impl core::fmt::Debug> {{\n", + ), + format!("\n}} {inner_fn_name}().unwrap() }}"), + ) + } else if test_id.is_some() { + ( + format!("fn main() {{ {inner_attr}fn {inner_fn_name}() {{\n",), + format!("\n}} {inner_fn_name}() }}"), + ) + } else { + ("fn main() {\n".into(), "\n}".into()) + }; + // Note on newlines: We insert a line/newline *before*, and *after* + // the doctest and adjust the `line_offset` accordingly. + // In the case of `-C instrument-coverage`, this means that the generated + // inner `main` function spans from the doctest opening codeblock to the + // closing one. For example + // /// ``` <- start of the inner main + // /// <- code under doctest + // /// ``` <- end of the inner main + line_offset += 1; + + prog.extend([&main_pre, everything_else, &main_post].iter().cloned()); + } + + debug!("final doctest:\n{prog}"); + + (prog, line_offset, supports_color) +} + +fn check_if_attr_is_complete(source: &str, edition: Edition) -> bool { + if source.is_empty() { + // Empty content so nothing to check in here... + return true; + } + rustc_driver::catch_fatal_errors(|| { + rustc_span::create_session_if_not_set_then(edition, |_| { + use rustc_errors::emitter::EmitterWriter; + use rustc_errors::Handler; + use rustc_span::source_map::FilePathMapping; + + let filename = FileName::anon_source_code(source); + // Any errors in parsing should also appear when the doctest is compiled for real, so just + // send all the errors that librustc_ast emits directly into a `Sink` instead of stderr. + let sm = Lrc::new(SourceMap::new(FilePathMapping::empty())); + let fallback_bundle = + rustc_errors::fallback_fluent_bundle(rustc_errors::DEFAULT_LOCALE_RESOURCES, false); + + let emitter = EmitterWriter::new( + Box::new(io::sink()), + None, + None, + fallback_bundle, + false, + false, + false, + None, + false, + ); + + let handler = Handler::with_emitter(false, None, Box::new(emitter)); + let sess = ParseSess::with_span_handler(handler, sm); + let mut parser = + match maybe_new_parser_from_source_str(&sess, filename, source.to_owned()) { + Ok(p) => p, + Err(_) => { + debug!("Cannot build a parser to check mod attr so skipping..."); + return true; + } + }; + // If a parsing error happened, it's very likely that the attribute is incomplete. + if let Err(e) = parser.parse_attribute(InnerAttrPolicy::Permitted) { + e.cancel(); + return false; + } + // We now check if there is an unclosed delimiter for the attribute. To do so, we look at + // the `unclosed_delims` and see if the opening square bracket was closed. + parser + .unclosed_delims() + .get(0) + .map(|unclosed| { + unclosed.unclosed_span.map(|s| s.lo()).unwrap_or(BytePos(0)) != BytePos(2) + }) + .unwrap_or(true) + }) + }) + .unwrap_or(false) +} + +fn partition_source(s: &str, edition: Edition) -> (String, String, String) { + #[derive(Copy, Clone, PartialEq)] + enum PartitionState { + Attrs, + Crates, + Other, + } + let mut state = PartitionState::Attrs; + let mut before = String::new(); + let mut crates = String::new(); + let mut after = String::new(); + + let mut mod_attr_pending = String::new(); + + for line in s.lines() { + let trimline = line.trim(); + + // FIXME(misdreavus): if a doc comment is placed on an extern crate statement, it will be + // shunted into "everything else" + match state { + PartitionState::Attrs => { + state = if trimline.starts_with("#![") { + if !check_if_attr_is_complete(line, edition) { + mod_attr_pending = line.to_owned(); + } else { + mod_attr_pending.clear(); + } + PartitionState::Attrs + } else if trimline.chars().all(|c| c.is_whitespace()) + || (trimline.starts_with("//") && !trimline.starts_with("///")) + { + PartitionState::Attrs + } else if trimline.starts_with("extern crate") + || trimline.starts_with("#[macro_use] extern crate") + { + PartitionState::Crates + } else { + // First we check if the previous attribute was "complete"... + if !mod_attr_pending.is_empty() { + // If not, then we append the new line into the pending attribute to check + // if this time it's complete... + mod_attr_pending.push_str(line); + if !trimline.is_empty() + && check_if_attr_is_complete(&mod_attr_pending, edition) + { + // If it's complete, then we can clear the pending content. + mod_attr_pending.clear(); + } + // In any case, this is considered as `PartitionState::Attrs` so it's + // prepended before rustdoc's inserts. + PartitionState::Attrs + } else { + PartitionState::Other + } + }; + } + PartitionState::Crates => { + state = if trimline.starts_with("extern crate") + || trimline.starts_with("#[macro_use] extern crate") + || trimline.chars().all(|c| c.is_whitespace()) + || (trimline.starts_with("//") && !trimline.starts_with("///")) + { + PartitionState::Crates + } else { + PartitionState::Other + }; + } + PartitionState::Other => {} + } + + match state { + PartitionState::Attrs => { + before.push_str(line); + before.push('\n'); + } + PartitionState::Crates => { + crates.push_str(line); + crates.push('\n'); + } + PartitionState::Other => { + after.push_str(line); + after.push('\n'); + } + } + } + + debug!("before:\n{before}"); + debug!("crates:\n{crates}"); + debug!("after:\n{after}"); + + (before, after, crates) +} + +pub(crate) trait Tester { + fn add_test(&mut self, test: String, config: LangString, line: usize); + fn get_line(&self) -> usize { + 0 + } + fn register_header(&mut self, _name: &str, _level: u32) {} +} + +pub(crate) struct Collector { + pub(crate) tests: Vec, + + // The name of the test displayed to the user, separated by `::`. + // + // In tests from Rust source, this is the path to the item + // e.g., `["std", "vec", "Vec", "push"]`. + // + // In tests from a markdown file, this is the titles of all headers (h1~h6) + // of the sections that contain the code block, e.g., if the markdown file is + // written as: + // + // ``````markdown + // # Title + // + // ## Subtitle + // + // ```rust + // assert!(true); + // ``` + // `````` + // + // the `names` vector of that test will be `["Title", "Subtitle"]`. + names: Vec, + + rustdoc_options: RustdocOptions, + use_headers: bool, + enable_per_target_ignores: bool, + crate_name: Symbol, + opts: GlobalTestOptions, + position: Span, + source_map: Option>, + filename: Option, + visited_tests: FxHashMap<(String, usize), usize>, + unused_extern_reports: Arc>>, + compiling_test_count: AtomicUsize, +} + +impl Collector { + pub(crate) fn new( + crate_name: Symbol, + rustdoc_options: RustdocOptions, + use_headers: bool, + opts: GlobalTestOptions, + source_map: Option>, + filename: Option, + enable_per_target_ignores: bool, + ) -> Collector { + Collector { + tests: Vec::new(), + names: Vec::new(), + rustdoc_options, + use_headers, + enable_per_target_ignores, + crate_name, + opts, + position: DUMMY_SP, + source_map, + filename, + visited_tests: FxHashMap::default(), + unused_extern_reports: Default::default(), + compiling_test_count: AtomicUsize::new(0), + } + } + + fn generate_name(&self, line: usize, filename: &FileName) -> String { + let mut item_path = self.names.join("::"); + item_path.retain(|c| c != ' '); + if !item_path.is_empty() { + item_path.push(' '); + } + format!("{} - {}(line {})", filename.prefer_local(), item_path, line) + } + + pub(crate) fn set_position(&mut self, position: Span) { + self.position = position; + } + + fn get_filename(&self) -> FileName { + if let Some(ref source_map) = self.source_map { + let filename = source_map.span_to_filename(self.position); + if let FileName::Real(ref filename) = filename { + if let Ok(cur_dir) = env::current_dir() { + if let Some(local_path) = filename.local_path() { + if let Ok(path) = local_path.strip_prefix(&cur_dir) { + return path.to_owned().into(); + } + } + } + } + filename + } else if let Some(ref filename) = self.filename { + filename.clone().into() + } else { + FileName::Custom("input".to_owned()) + } + } +} + +impl Tester for Collector { + fn add_test(&mut self, test: String, config: LangString, line: usize) { + let filename = self.get_filename(); + let name = self.generate_name(line, &filename); + let crate_name = self.crate_name.to_string(); + let opts = self.opts.clone(); + let edition = config.edition.unwrap_or(self.rustdoc_options.edition); + let rustdoc_options = self.rustdoc_options.clone(); + let runtool = self.rustdoc_options.runtool.clone(); + let runtool_args = self.rustdoc_options.runtool_args.clone(); + let target = self.rustdoc_options.target.clone(); + let target_str = target.to_string(); + let unused_externs = self.unused_extern_reports.clone(); + let no_run = config.no_run || rustdoc_options.no_run; + if !config.compile_fail { + self.compiling_test_count.fetch_add(1, Ordering::SeqCst); + } + + let path = match &filename { + FileName::Real(path) => { + if let Some(local_path) = path.local_path() { + local_path.to_path_buf() + } else { + // Somehow we got the filename from the metadata of another crate, should never happen + unreachable!("doctest from a different crate"); + } + } + _ => PathBuf::from(r"doctest.rs"), + }; + + // For example `module/file.rs` would become `module_file_rs` + let file = filename + .prefer_local() + .to_string_lossy() + .chars() + .map(|c| if c.is_ascii_alphanumeric() { c } else { '_' }) + .collect::(); + let test_id = format!( + "{file}_{line}_{number}", + file = file, + line = line, + number = { + // Increases the current test number, if this file already + // exists or it creates a new entry with a test number of 0. + self.visited_tests.entry((file.clone(), line)).and_modify(|v| *v += 1).or_insert(0) + }, + ); + let outdir = if let Some(mut path) = rustdoc_options.persist_doctests.clone() { + path.push(&test_id); + + if let Err(err) = std::fs::create_dir_all(&path) { + eprintln!("Couldn't create directory for doctest executables: {}", err); + panic::resume_unwind(Box::new(())); + } + + DirState::Perm(path) + } else { + DirState::Temp( + TempFileBuilder::new() + .prefix("rustdoctest") + .tempdir() + .expect("rustdoc needs a tempdir"), + ) + }; + + debug!("creating test {name}: {test}"); + self.tests.push(test::TestDescAndFn { + desc: test::TestDesc { + name: test::DynTestName(name), + ignore: match config.ignore { + Ignore::All => true, + Ignore::None => false, + Ignore::Some(ref ignores) => ignores.iter().any(|s| target_str.contains(s)), + }, + ignore_message: None, + // compiler failures are test failures + should_panic: test::ShouldPanic::No, + compile_fail: config.compile_fail, + no_run, + test_type: test::TestType::DocTest, + }, + testfn: test::DynTestFn(Box::new(move || { + let report_unused_externs = |uext| { + unused_externs.lock().unwrap().push(uext); + }; + let res = run_test( + &test, + &crate_name, + line, + rustdoc_options, + config, + no_run, + runtool, + runtool_args, + target, + &opts, + edition, + outdir, + path, + &test_id, + report_unused_externs, + ); + + if let Err(err) = res { + match err { + TestFailure::CompileError => { + eprint!("Couldn't compile the test."); + } + TestFailure::UnexpectedCompilePass => { + eprint!("Test compiled successfully, but it's marked `compile_fail`."); + } + TestFailure::UnexpectedRunPass => { + eprint!("Test executable succeeded, but it's marked `should_panic`."); + } + TestFailure::MissingErrorCodes(codes) => { + eprint!("Some expected error codes were not found: {:?}", codes); + } + TestFailure::ExecutionError(err) => { + eprint!("Couldn't run the test: {err}"); + if err.kind() == io::ErrorKind::PermissionDenied { + eprint!(" - maybe your tempdir is mounted with noexec?"); + } + } + TestFailure::ExecutionFailure(out) => { + eprintln!("Test executable failed ({reason}).", reason = out.status); + + // FIXME(#12309): An unfortunate side-effect of capturing the test + // executable's output is that the relative ordering between the test's + // stdout and stderr is lost. However, this is better than the + // alternative: if the test executable inherited the parent's I/O + // handles the output wouldn't be captured at all, even on success. + // + // The ordering could be preserved if the test process' stderr was + // redirected to stdout, but that functionality does not exist in the + // standard library, so it may not be portable enough. + let stdout = str::from_utf8(&out.stdout).unwrap_or_default(); + let stderr = str::from_utf8(&out.stderr).unwrap_or_default(); + + if !stdout.is_empty() || !stderr.is_empty() { + eprintln!(); + + if !stdout.is_empty() { + eprintln!("stdout:\n{stdout}"); + } + + if !stderr.is_empty() { + eprintln!("stderr:\n{stderr}"); + } + } + } + } + + panic::resume_unwind(Box::new(())); + } + })), + }); + } + + fn get_line(&self) -> usize { + if let Some(ref source_map) = self.source_map { + let line = self.position.lo().to_usize(); + let line = source_map.lookup_char_pos(BytePos(line as u32)).line; + if line > 0 { line - 1 } else { line } + } else { + 0 + } + } + + fn register_header(&mut self, name: &str, level: u32) { + if self.use_headers { + // We use these headings as test names, so it's good if + // they're valid identifiers. + let name = name + .chars() + .enumerate() + .map(|(i, c)| { + if (i == 0 && rustc_lexer::is_id_start(c)) + || (i != 0 && rustc_lexer::is_id_continue(c)) + { + c + } else { + '_' + } + }) + .collect::(); + + // Here we try to efficiently assemble the header titles into the + // test name in the form of `h1::h2::h3::h4::h5::h6`. + // + // Suppose that originally `self.names` contains `[h1, h2, h3]`... + let level = level as usize; + if level <= self.names.len() { + // ... Consider `level == 2`. All headers in the lower levels + // are irrelevant in this new level. So we should reset + // `self.names` to contain headers until

, and replace that + // slot with the new name: `[h1, name]`. + self.names.truncate(level); + self.names[level - 1] = name; + } else { + // ... On the other hand, consider `level == 5`. This means we + // need to extend `self.names` to contain five headers. We fill + // in the missing level (

) with `_`. Thus `self.names` will + // become `[h1, h2, h3, "_", name]`. + if level - 1 > self.names.len() { + self.names.resize(level - 1, "_".to_owned()); + } + self.names.push(name); + } + } + } +} + +struct HirCollector<'a, 'hir, 'tcx> { + sess: &'a Session, + collector: &'a mut Collector, + map: Map<'hir>, + codes: ErrorCodes, + tcx: TyCtxt<'tcx>, +} + +impl<'a, 'hir, 'tcx> HirCollector<'a, 'hir, 'tcx> { + fn visit_testable( + &mut self, + name: String, + hir_id: HirId, + sp: Span, + nested: F, + ) { + let ast_attrs = self.tcx.hir().attrs(hir_id); + if let Some(ref cfg) = ast_attrs.cfg(self.tcx, &FxHashSet::default()) { + if !cfg.matches(&self.sess.parse_sess, Some(self.sess.features_untracked())) { + return; + } + } + + let has_name = !name.is_empty(); + if has_name { + self.collector.names.push(name); + } + + // The collapse-docs pass won't combine sugared/raw doc attributes, or included files with + // anything else, this will combine them for us. + let attrs = Attributes::from_ast(ast_attrs); + if let Some(doc) = attrs.collapsed_doc_value() { + // Use the outermost invocation, so that doctest names come from where the docs were written. + let span = ast_attrs + .span() + .map(|span| span.ctxt().outer_expn().expansion_cause().unwrap_or(span)) + .unwrap_or(DUMMY_SP); + self.collector.set_position(span); + markdown::find_testable_code( + &doc, + self.collector, + self.codes, + self.collector.enable_per_target_ignores, + Some(&crate::html::markdown::ExtraInfo::new( + self.tcx, + hir_id, + span_of_attrs(&attrs).unwrap_or(sp), + )), + ); + } + + nested(self); + + if has_name { + self.collector.names.pop(); + } + } +} + +impl<'a, 'hir, 'tcx> intravisit::Visitor<'hir> for HirCollector<'a, 'hir, 'tcx> { + type NestedFilter = nested_filter::All; + + fn nested_visit_map(&mut self) -> Self::Map { + self.map + } + + fn visit_item(&mut self, item: &'hir hir::Item<'_>) { + let name = match &item.kind { + hir::ItemKind::Impl(impl_) => { + rustc_hir_pretty::id_to_string(&self.map, impl_.self_ty.hir_id) + } + _ => item.ident.to_string(), + }; + + self.visit_testable(name, item.hir_id(), item.span, |this| { + intravisit::walk_item(this, item); + }); + } + + fn visit_trait_item(&mut self, item: &'hir hir::TraitItem<'_>) { + self.visit_testable(item.ident.to_string(), item.hir_id(), item.span, |this| { + intravisit::walk_trait_item(this, item); + }); + } + + fn visit_impl_item(&mut self, item: &'hir hir::ImplItem<'_>) { + self.visit_testable(item.ident.to_string(), item.hir_id(), item.span, |this| { + intravisit::walk_impl_item(this, item); + }); + } + + fn visit_foreign_item(&mut self, item: &'hir hir::ForeignItem<'_>) { + self.visit_testable(item.ident.to_string(), item.hir_id(), item.span, |this| { + intravisit::walk_foreign_item(this, item); + }); + } + + fn visit_variant( + &mut self, + v: &'hir hir::Variant<'_>, + g: &'hir hir::Generics<'_>, + item_id: hir::HirId, + ) { + self.visit_testable(v.ident.to_string(), v.id, v.span, |this| { + intravisit::walk_variant(this, v, g, item_id); + }); + } + + fn visit_field_def(&mut self, f: &'hir hir::FieldDef<'_>) { + self.visit_testable(f.ident.to_string(), f.hir_id, f.span, |this| { + intravisit::walk_field_def(this, f); + }); + } +} + +#[cfg(test)] +mod tests; diff --git a/src/librustdoc/doctest/tests.rs b/src/librustdoc/doctest/tests.rs new file mode 100644 index 000000000..360d2259e --- /dev/null +++ b/src/librustdoc/doctest/tests.rs @@ -0,0 +1,300 @@ +use super::{make_test, GlobalTestOptions}; +use rustc_span::edition::DEFAULT_EDITION; + +#[test] +fn make_test_basic() { + //basic use: wraps with `fn main`, adds `#![allow(unused)]` + let opts = GlobalTestOptions::default(); + let input = "assert_eq!(2+2, 4);"; + let expected = "#![allow(unused)] +fn main() { +assert_eq!(2+2, 4); +}" + .to_string(); + let (output, len, _) = make_test(input, None, false, &opts, DEFAULT_EDITION, None); + assert_eq!((output, len), (expected, 2)); +} + +#[test] +fn make_test_crate_name_no_use() { + // If you give a crate name but *don't* use it within the test, it won't bother inserting + // the `extern crate` statement. + let opts = GlobalTestOptions::default(); + let input = "assert_eq!(2+2, 4);"; + let expected = "#![allow(unused)] +fn main() { +assert_eq!(2+2, 4); +}" + .to_string(); + let (output, len, _) = make_test(input, Some("asdf"), false, &opts, DEFAULT_EDITION, None); + assert_eq!((output, len), (expected, 2)); +} + +#[test] +fn make_test_crate_name() { + // If you give a crate name and use it within the test, it will insert an `extern crate` + // statement before `fn main`. + let opts = GlobalTestOptions::default(); + let input = "use asdf::qwop; +assert_eq!(2+2, 4);"; + let expected = "#![allow(unused)] +extern crate r#asdf; +fn main() { +use asdf::qwop; +assert_eq!(2+2, 4); +}" + .to_string(); + let (output, len, _) = make_test(input, Some("asdf"), false, &opts, DEFAULT_EDITION, None); + assert_eq!((output, len), (expected, 3)); +} + +#[test] +fn make_test_no_crate_inject() { + // Even if you do use the crate within the test, setting `opts.no_crate_inject` will skip + // adding it anyway. + let opts = GlobalTestOptions { no_crate_inject: true, attrs: vec![] }; + let input = "use asdf::qwop; +assert_eq!(2+2, 4);"; + let expected = "#![allow(unused)] +fn main() { +use asdf::qwop; +assert_eq!(2+2, 4); +}" + .to_string(); + let (output, len, _) = make_test(input, Some("asdf"), false, &opts, DEFAULT_EDITION, None); + assert_eq!((output, len), (expected, 2)); +} + +#[test] +fn make_test_ignore_std() { + // Even if you include a crate name, and use it in the doctest, we still won't include an + // `extern crate` statement if the crate is "std" -- that's included already by the + // compiler! + let opts = GlobalTestOptions::default(); + let input = "use std::*; +assert_eq!(2+2, 4);"; + let expected = "#![allow(unused)] +fn main() { +use std::*; +assert_eq!(2+2, 4); +}" + .to_string(); + let (output, len, _) = make_test(input, Some("std"), false, &opts, DEFAULT_EDITION, None); + assert_eq!((output, len), (expected, 2)); +} + +#[test] +fn make_test_manual_extern_crate() { + // When you manually include an `extern crate` statement in your doctest, `make_test` + // assumes you've included one for your own crate too. + let opts = GlobalTestOptions::default(); + let input = "extern crate asdf; +use asdf::qwop; +assert_eq!(2+2, 4);"; + let expected = "#![allow(unused)] +extern crate asdf; +fn main() { +use asdf::qwop; +assert_eq!(2+2, 4); +}" + .to_string(); + let (output, len, _) = make_test(input, Some("asdf"), false, &opts, DEFAULT_EDITION, None); + assert_eq!((output, len), (expected, 2)); +} + +#[test] +fn make_test_manual_extern_crate_with_macro_use() { + let opts = GlobalTestOptions::default(); + let input = "#[macro_use] extern crate asdf; +use asdf::qwop; +assert_eq!(2+2, 4);"; + let expected = "#![allow(unused)] +#[macro_use] extern crate asdf; +fn main() { +use asdf::qwop; +assert_eq!(2+2, 4); +}" + .to_string(); + let (output, len, _) = make_test(input, Some("asdf"), false, &opts, DEFAULT_EDITION, None); + assert_eq!((output, len), (expected, 2)); +} + +#[test] +fn make_test_opts_attrs() { + // If you supplied some doctest attributes with `#![doc(test(attr(...)))]`, it will use + // those instead of the stock `#![allow(unused)]`. + let mut opts = GlobalTestOptions::default(); + opts.attrs.push("feature(sick_rad)".to_string()); + let input = "use asdf::qwop; +assert_eq!(2+2, 4);"; + let expected = "#![feature(sick_rad)] +extern crate r#asdf; +fn main() { +use asdf::qwop; +assert_eq!(2+2, 4); +}" + .to_string(); + let (output, len, _) = make_test(input, Some("asdf"), false, &opts, DEFAULT_EDITION, None); + assert_eq!((output, len), (expected, 3)); + + // Adding more will also bump the returned line offset. + opts.attrs.push("feature(hella_dope)".to_string()); + let expected = "#![feature(sick_rad)] +#![feature(hella_dope)] +extern crate r#asdf; +fn main() { +use asdf::qwop; +assert_eq!(2+2, 4); +}" + .to_string(); + let (output, len, _) = make_test(input, Some("asdf"), false, &opts, DEFAULT_EDITION, None); + assert_eq!((output, len), (expected, 4)); +} + +#[test] +fn make_test_crate_attrs() { + // Including inner attributes in your doctest will apply them to the whole "crate", pasting + // them outside the generated main function. + let opts = GlobalTestOptions::default(); + let input = "#![feature(sick_rad)] +assert_eq!(2+2, 4);"; + let expected = "#![allow(unused)] +#![feature(sick_rad)] +fn main() { +assert_eq!(2+2, 4); +}" + .to_string(); + let (output, len, _) = make_test(input, None, false, &opts, DEFAULT_EDITION, None); + assert_eq!((output, len), (expected, 2)); +} + +#[test] +fn make_test_with_main() { + // Including your own `fn main` wrapper lets the test use it verbatim. + let opts = GlobalTestOptions::default(); + let input = "fn main() { + assert_eq!(2+2, 4); +}"; + let expected = "#![allow(unused)] +fn main() { + assert_eq!(2+2, 4); +}" + .to_string(); + let (output, len, _) = make_test(input, None, false, &opts, DEFAULT_EDITION, None); + assert_eq!((output, len), (expected, 1)); +} + +#[test] +fn make_test_fake_main() { + // ... but putting it in a comment will still provide a wrapper. + let opts = GlobalTestOptions::default(); + let input = "//Ceci n'est pas une `fn main` +assert_eq!(2+2, 4);"; + let expected = "#![allow(unused)] +//Ceci n'est pas une `fn main` +fn main() { +assert_eq!(2+2, 4); +}" + .to_string(); + let (output, len, _) = make_test(input, None, false, &opts, DEFAULT_EDITION, None); + assert_eq!((output, len), (expected, 2)); +} + +#[test] +fn make_test_dont_insert_main() { + // Even with that, if you set `dont_insert_main`, it won't create the `fn main` wrapper. + let opts = GlobalTestOptions::default(); + let input = "//Ceci n'est pas une `fn main` +assert_eq!(2+2, 4);"; + let expected = "#![allow(unused)] +//Ceci n'est pas une `fn main` +assert_eq!(2+2, 4);" + .to_string(); + let (output, len, _) = make_test(input, None, true, &opts, DEFAULT_EDITION, None); + assert_eq!((output, len), (expected, 1)); +} + +#[test] +fn make_test_issues_21299_33731() { + let opts = GlobalTestOptions::default(); + + let input = "// fn main +assert_eq!(2+2, 4);"; + + let expected = "#![allow(unused)] +// fn main +fn main() { +assert_eq!(2+2, 4); +}" + .to_string(); + + let (output, len, _) = make_test(input, None, false, &opts, DEFAULT_EDITION, None); + assert_eq!((output, len), (expected, 2)); + + let input = "extern crate hella_qwop; +assert_eq!(asdf::foo, 4);"; + + let expected = "#![allow(unused)] +extern crate hella_qwop; +extern crate r#asdf; +fn main() { +assert_eq!(asdf::foo, 4); +}" + .to_string(); + + let (output, len, _) = make_test(input, Some("asdf"), false, &opts, DEFAULT_EDITION, None); + assert_eq!((output, len), (expected, 3)); +} + +#[test] +fn make_test_main_in_macro() { + let opts = GlobalTestOptions::default(); + let input = "#[macro_use] extern crate my_crate; +test_wrapper! { + fn main() {} +}"; + let expected = "#![allow(unused)] +#[macro_use] extern crate my_crate; +test_wrapper! { + fn main() {} +}" + .to_string(); + + let (output, len, _) = make_test(input, Some("my_crate"), false, &opts, DEFAULT_EDITION, None); + assert_eq!((output, len), (expected, 1)); +} + +#[test] +fn make_test_returns_result() { + // creates an inner function and unwraps it + let opts = GlobalTestOptions::default(); + let input = "use std::io; +let mut input = String::new(); +io::stdin().read_line(&mut input)?; +Ok::<(), io:Error>(())"; + let expected = "#![allow(unused)] +fn main() { fn _inner() -> Result<(), impl core::fmt::Debug> { +use std::io; +let mut input = String::new(); +io::stdin().read_line(&mut input)?; +Ok::<(), io:Error>(()) +} _inner().unwrap() }" + .to_string(); + let (output, len, _) = make_test(input, None, false, &opts, DEFAULT_EDITION, None); + assert_eq!((output, len), (expected, 2)); +} + +#[test] +fn make_test_named_wrapper() { + // creates an inner function with a specific name + let opts = GlobalTestOptions::default(); + let input = "assert_eq!(2+2, 4);"; + let expected = "#![allow(unused)] +fn main() { #[allow(non_snake_case)] fn _doctest_main__some_unique_name() { +assert_eq!(2+2, 4); +} _doctest_main__some_unique_name() }" + .to_string(); + let (output, len, _) = + make_test(input, None, false, &opts, DEFAULT_EDITION, Some("_some_unique_name")); + assert_eq!((output, len), (expected, 2)); +} diff --git a/src/librustdoc/error.rs b/src/librustdoc/error.rs new file mode 100644 index 000000000..6ed7eab1a --- /dev/null +++ b/src/librustdoc/error.rs @@ -0,0 +1,59 @@ +use std::error; +use std::fmt::{self, Formatter}; +use std::path::{Path, PathBuf}; + +use crate::docfs::PathError; + +#[derive(Debug)] +pub(crate) struct Error { + pub(crate) file: PathBuf, + pub(crate) error: String, +} + +impl error::Error for Error {} + +impl std::fmt::Display for Error { + fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result { + let file = self.file.display().to_string(); + if file.is_empty() { + write!(f, "{}", self.error) + } else { + write!(f, "\"{}\": {}", self.file.display(), self.error) + } + } +} + +impl PathError for Error { + fn new>(e: S, path: P) -> Error + where + S: ToString + Sized, + { + Error { file: path.as_ref().to_path_buf(), error: e.to_string() } + } +} + +#[macro_export] +macro_rules! try_none { + ($e:expr, $file:expr) => {{ + use std::io; + match $e { + Some(e) => e, + None => { + return Err(::new( + io::Error::new(io::ErrorKind::Other, "not found"), + $file, + )); + } + } + }}; +} + +#[macro_export] +macro_rules! try_err { + ($e:expr, $file:expr) => {{ + match $e { + Ok(e) => e, + Err(e) => return Err(Error::new(e, $file)), + } + }}; +} diff --git a/src/librustdoc/externalfiles.rs b/src/librustdoc/externalfiles.rs new file mode 100644 index 000000000..37fd909c9 --- /dev/null +++ b/src/librustdoc/externalfiles.rs @@ -0,0 +1,107 @@ +use crate::html::markdown::{ErrorCodes, HeadingOffset, IdMap, Markdown, Playground}; +use crate::rustc_span::edition::Edition; +use std::fs; +use std::path::Path; +use std::str; + +use serde::Serialize; + +#[derive(Clone, Debug, Serialize)] +pub(crate) struct ExternalHtml { + /// Content that will be included inline in the `` section of a + /// rendered Markdown file or generated documentation + pub(crate) in_header: String, + /// Content that will be included inline between `` and the content of + /// a rendered Markdown file or generated documentation + pub(crate) before_content: String, + /// Content that will be included inline between the content and `` of + /// a rendered Markdown file or generated documentation + pub(crate) after_content: String, +} + +impl ExternalHtml { + pub(crate) fn load( + in_header: &[String], + before_content: &[String], + after_content: &[String], + md_before_content: &[String], + md_after_content: &[String], + nightly_build: bool, + diag: &rustc_errors::Handler, + id_map: &mut IdMap, + edition: Edition, + playground: &Option, + ) -> Option { + let codes = ErrorCodes::from(nightly_build); + let ih = load_external_files(in_header, diag)?; + let bc = load_external_files(before_content, diag)?; + let m_bc = load_external_files(md_before_content, diag)?; + let bc = format!( + "{}{}", + bc, + Markdown { + content: &m_bc, + links: &[], + ids: id_map, + error_codes: codes, + edition, + playground, + heading_offset: HeadingOffset::H2, + } + .into_string() + ); + let ac = load_external_files(after_content, diag)?; + let m_ac = load_external_files(md_after_content, diag)?; + let ac = format!( + "{}{}", + ac, + Markdown { + content: &m_ac, + links: &[], + ids: id_map, + error_codes: codes, + edition, + playground, + heading_offset: HeadingOffset::H2, + } + .into_string() + ); + Some(ExternalHtml { in_header: ih, before_content: bc, after_content: ac }) + } +} + +pub(crate) enum LoadStringError { + ReadFail, + BadUtf8, +} + +pub(crate) fn load_string>( + file_path: P, + diag: &rustc_errors::Handler, +) -> Result { + let file_path = file_path.as_ref(); + let contents = match fs::read(file_path) { + Ok(bytes) => bytes, + Err(e) => { + diag.struct_err(&format!("error reading `{}`: {}", file_path.display(), e)).emit(); + return Err(LoadStringError::ReadFail); + } + }; + match str::from_utf8(&contents) { + Ok(s) => Ok(s.to_string()), + Err(_) => { + diag.struct_err(&format!("error reading `{}`: not UTF-8", file_path.display())).emit(); + Err(LoadStringError::BadUtf8) + } + } +} + +fn load_external_files(names: &[String], diag: &rustc_errors::Handler) -> Option { + let mut out = String::new(); + for name in names { + let Ok(s) = load_string(name, diag) else { return None }; + out.push_str(&s); + out.push('\n'); + } + Some(out) +} diff --git a/src/librustdoc/fold.rs b/src/librustdoc/fold.rs new file mode 100644 index 000000000..6b7e67e2c --- /dev/null +++ b/src/librustdoc/fold.rs @@ -0,0 +1,103 @@ +use crate::clean::*; + +pub(crate) fn strip_item(mut item: Item) -> Item { + if !matches!(*item.kind, StrippedItem(..)) { + item.kind = Box::new(StrippedItem(item.kind)); + } + item +} + +pub(crate) trait DocFolder: Sized { + fn fold_item(&mut self, item: Item) -> Option { + Some(self.fold_item_recur(item)) + } + + /// don't override! + fn fold_inner_recur(&mut self, kind: ItemKind) -> ItemKind { + match kind { + StrippedItem(..) => unreachable!(), + ModuleItem(i) => ModuleItem(self.fold_mod(i)), + StructItem(mut i) => { + i.fields = i.fields.into_iter().filter_map(|x| self.fold_item(x)).collect(); + StructItem(i) + } + UnionItem(mut i) => { + i.fields = i.fields.into_iter().filter_map(|x| self.fold_item(x)).collect(); + UnionItem(i) + } + EnumItem(mut i) => { + i.variants = i.variants.into_iter().filter_map(|x| self.fold_item(x)).collect(); + EnumItem(i) + } + TraitItem(mut i) => { + i.items = i.items.into_iter().filter_map(|x| self.fold_item(x)).collect(); + TraitItem(i) + } + ImplItem(mut i) => { + i.items = i.items.into_iter().filter_map(|x| self.fold_item(x)).collect(); + ImplItem(i) + } + VariantItem(i) => match i { + Variant::Struct(mut j) => { + j.fields = j.fields.into_iter().filter_map(|x| self.fold_item(x)).collect(); + VariantItem(Variant::Struct(j)) + } + Variant::Tuple(fields) => { + let fields = fields.into_iter().filter_map(|x| self.fold_item(x)).collect(); + VariantItem(Variant::Tuple(fields)) + } + Variant::CLike => VariantItem(Variant::CLike), + }, + ExternCrateItem { src: _ } + | ImportItem(_) + | FunctionItem(_) + | TypedefItem(_) + | OpaqueTyItem(_) + | StaticItem(_) + | ConstantItem(_) + | TraitAliasItem(_) + | TyMethodItem(_) + | MethodItem(_, _) + | StructFieldItem(_) + | ForeignFunctionItem(_) + | ForeignStaticItem(_) + | ForeignTypeItem + | MacroItem(_) + | ProcMacroItem(_) + | PrimitiveItem(_) + | TyAssocConstItem(..) + | AssocConstItem(..) + | TyAssocTypeItem(..) + | AssocTypeItem(..) + | KeywordItem => kind, + } + } + + /// don't override! + fn fold_item_recur(&mut self, mut item: Item) -> Item { + item.kind = Box::new(match *item.kind { + StrippedItem(box i) => StrippedItem(Box::new(self.fold_inner_recur(i))), + _ => self.fold_inner_recur(*item.kind), + }); + item + } + + fn fold_mod(&mut self, m: Module) -> Module { + Module { + span: m.span, + items: m.items.into_iter().filter_map(|i| self.fold_item(i)).collect(), + } + } + + fn fold_crate(&mut self, mut c: Crate) -> Crate { + c.module = self.fold_item(c.module).unwrap(); + + let external_traits = { std::mem::take(&mut *c.external_traits.borrow_mut()) }; + for (k, mut v) in external_traits { + v.trait_.items = v.trait_.items.into_iter().filter_map(|i| self.fold_item(i)).collect(); + c.external_traits.borrow_mut().insert(k, v); + } + + c + } +} diff --git a/src/librustdoc/formats/cache.rs b/src/librustdoc/formats/cache.rs new file mode 100644 index 000000000..2b2691e53 --- /dev/null +++ b/src/librustdoc/formats/cache.rs @@ -0,0 +1,569 @@ +use std::mem; + +use rustc_data_structures::fx::{FxHashMap, FxHashSet}; +use rustc_hir::def_id::{CrateNum, DefId}; +use rustc_middle::middle::privacy::AccessLevels; +use rustc_middle::ty::{self, TyCtxt}; +use rustc_span::{sym, Symbol}; + +use crate::clean::{self, types::ExternalLocation, ExternalCrate, ItemId, PrimitiveType}; +use crate::core::DocContext; +use crate::fold::DocFolder; +use crate::formats::item_type::ItemType; +use crate::formats::Impl; +use crate::html::format::join_with_double_colon; +use crate::html::markdown::short_markdown_summary; +use crate::html::render::search_index::get_function_type_for_search; +use crate::html::render::IndexItem; + +/// This cache is used to store information about the [`clean::Crate`] being +/// rendered in order to provide more useful documentation. This contains +/// information like all implementors of a trait, all traits a type implements, +/// documentation for all known traits, etc. +/// +/// This structure purposefully does not implement `Clone` because it's intended +/// to be a fairly large and expensive structure to clone. Instead this adheres +/// to `Send` so it may be stored in an `Arc` instance and shared among the various +/// rendering threads. +#[derive(Default)] +pub(crate) struct Cache { + /// Maps a type ID to all known implementations for that type. This is only + /// recognized for intra-crate [`clean::Type::Path`]s, and is used to print + /// out extra documentation on the page of an enum/struct. + /// + /// The values of the map are a list of implementations and documentation + /// found on that implementation. + pub(crate) impls: FxHashMap>, + + /// Maintains a mapping of local crate `DefId`s to the fully qualified name + /// and "short type description" of that node. This is used when generating + /// URLs when a type is being linked to. External paths are not located in + /// this map because the `External` type itself has all the information + /// necessary. + pub(crate) paths: FxHashMap, ItemType)>, + + /// Similar to `paths`, but only holds external paths. This is only used for + /// generating explicit hyperlinks to other crates. + pub(crate) external_paths: FxHashMap, ItemType)>, + + /// Maps local `DefId`s of exported types to fully qualified paths. + /// Unlike 'paths', this mapping ignores any renames that occur + /// due to 'use' statements. + /// + /// This map is used when writing out the special 'implementors' + /// javascript file. By using the exact path that the type + /// is declared with, we ensure that each path will be identical + /// to the path used if the corresponding type is inlined. By + /// doing this, we can detect duplicate impls on a trait page, and only display + /// the impl for the inlined type. + pub(crate) exact_paths: FxHashMap>, + + /// This map contains information about all known traits of this crate. + /// Implementations of a crate should inherit the documentation of the + /// parent trait if no extra documentation is specified, and default methods + /// should show up in documentation about trait implementations. + pub(crate) traits: FxHashMap, + + /// When rendering traits, it's often useful to be able to list all + /// implementors of the trait, and this mapping is exactly, that: a mapping + /// of trait ids to the list of known implementors of the trait + pub(crate) implementors: FxHashMap>, + + /// Cache of where external crate documentation can be found. + pub(crate) extern_locations: FxHashMap, + + /// Cache of where documentation for primitives can be found. + pub(crate) primitive_locations: FxHashMap, + + // Note that external items for which `doc(hidden)` applies to are shown as + // non-reachable while local items aren't. This is because we're reusing + // the access levels from the privacy check pass. + pub(crate) access_levels: AccessLevels, + + /// The version of the crate being documented, if given from the `--crate-version` flag. + pub(crate) crate_version: Option, + + /// Whether to document private items. + /// This is stored in `Cache` so it doesn't need to be passed through all rustdoc functions. + pub(crate) document_private: bool, + + /// Crates marked with [`#[doc(masked)]`][doc_masked]. + /// + /// [doc_masked]: https://doc.rust-lang.org/nightly/unstable-book/language-features/doc-masked.html + pub(crate) masked_crates: FxHashSet, + + // Private fields only used when initially crawling a crate to build a cache + stack: Vec, + parent_stack: Vec, + stripped_mod: bool, + + pub(crate) search_index: Vec, + + // In rare case where a structure is defined in one module but implemented + // in another, if the implementing module is parsed before defining module, + // then the fully qualified name of the structure isn't presented in `paths` + // yet when its implementation methods are being indexed. Caches such methods + // and their parent id here and indexes them at the end of crate parsing. + pub(crate) orphan_impl_items: Vec, + + // Similarly to `orphan_impl_items`, sometimes trait impls are picked up + // even though the trait itself is not exported. This can happen if a trait + // was defined in function/expression scope, since the impl will be picked + // up by `collect-trait-impls` but the trait won't be scraped out in the HIR + // crawl. In order to prevent crashes when looking for notable traits or + // when gathering trait documentation on a type, hold impls here while + // folding and add them to the cache later on if we find the trait. + orphan_trait_impls: Vec<(DefId, FxHashSet, Impl)>, + + /// All intra-doc links resolved so far. + /// + /// Links are indexed by the DefId of the item they document. + pub(crate) intra_doc_links: FxHashMap>, + /// Cfg that have been hidden via #![doc(cfg_hide(...))] + pub(crate) hidden_cfg: FxHashSet, +} + +/// This struct is used to wrap the `cache` and `tcx` in order to run `DocFolder`. +struct CacheBuilder<'a, 'tcx> { + cache: &'a mut Cache, + /// This field is used to prevent duplicated impl blocks. + impl_ids: FxHashMap>, + tcx: TyCtxt<'tcx>, +} + +impl Cache { + pub(crate) fn new(access_levels: AccessLevels, document_private: bool) -> Self { + Cache { access_levels, document_private, ..Cache::default() } + } + + /// Populates the `Cache` with more data. The returned `Crate` will be missing some data that was + /// in `krate` due to the data being moved into the `Cache`. + pub(crate) fn populate(cx: &mut DocContext<'_>, mut krate: clean::Crate) -> clean::Crate { + let tcx = cx.tcx; + + // Crawl the crate to build various caches used for the output + debug!(?cx.cache.crate_version); + cx.cache.traits = krate.external_traits.take(); + + // Cache where all our extern crates are located + // FIXME: this part is specific to HTML so it'd be nice to remove it from the common code + for &crate_num in cx.tcx.crates(()) { + let e = ExternalCrate { crate_num }; + + let name = e.name(tcx); + let render_options = &cx.render_options; + let extern_url = render_options.extern_html_root_urls.get(name.as_str()).map(|u| &**u); + let extern_url_takes_precedence = render_options.extern_html_root_takes_precedence; + let dst = &render_options.output; + let location = e.location(extern_url, extern_url_takes_precedence, dst, tcx); + cx.cache.extern_locations.insert(e.crate_num, location); + cx.cache.external_paths.insert(e.def_id(), (vec![name], ItemType::Module)); + } + + // FIXME: avoid this clone (requires implementing Default manually) + cx.cache.primitive_locations = PrimitiveType::primitive_locations(tcx).clone(); + for (prim, &def_id) in &cx.cache.primitive_locations { + let crate_name = tcx.crate_name(def_id.krate); + // Recall that we only allow primitive modules to be at the root-level of the crate. + // If that restriction is ever lifted, this will have to include the relative paths instead. + cx.cache + .external_paths + .insert(def_id, (vec![crate_name, prim.as_sym()], ItemType::Primitive)); + } + + let (krate, mut impl_ids) = { + let mut cache_builder = + CacheBuilder { tcx, cache: &mut cx.cache, impl_ids: FxHashMap::default() }; + krate = cache_builder.fold_crate(krate); + (krate, cache_builder.impl_ids) + }; + + for (trait_did, dids, impl_) in cx.cache.orphan_trait_impls.drain(..) { + if cx.cache.traits.contains_key(&trait_did) { + for did in dids { + if impl_ids.entry(did).or_default().insert(impl_.def_id()) { + cx.cache.impls.entry(did).or_default().push(impl_.clone()); + } + } + } + } + + krate + } +} + +impl<'a, 'tcx> DocFolder for CacheBuilder<'a, 'tcx> { + fn fold_item(&mut self, item: clean::Item) -> Option { + if item.item_id.is_local() { + debug!("folding {} \"{:?}\", id {:?}", item.type_(), item.name, item.item_id); + } + + // If this is a stripped module, + // we don't want it or its children in the search index. + let orig_stripped_mod = match *item.kind { + clean::StrippedItem(box clean::ModuleItem(..)) => { + mem::replace(&mut self.cache.stripped_mod, true) + } + _ => self.cache.stripped_mod, + }; + + // If the impl is from a masked crate or references something from a + // masked crate then remove it completely. + if let clean::ImplItem(ref i) = *item.kind { + if self.cache.masked_crates.contains(&item.item_id.krate()) + || i.trait_ + .as_ref() + .map_or(false, |t| self.cache.masked_crates.contains(&t.def_id().krate)) + || i.for_ + .def_id(self.cache) + .map_or(false, |d| self.cache.masked_crates.contains(&d.krate)) + { + return None; + } + } + + // Propagate a trait method's documentation to all implementors of the + // trait. + if let clean::TraitItem(ref t) = *item.kind { + self.cache.traits.entry(item.item_id.expect_def_id()).or_insert_with(|| { + clean::TraitWithExtraInfo { + trait_: t.clone(), + is_notable: item.attrs.has_doc_flag(sym::notable_trait), + } + }); + } + + // Collect all the implementors of traits. + if let clean::ImplItem(ref i) = *item.kind { + if let Some(trait_) = &i.trait_ { + if !i.kind.is_blanket() { + self.cache + .implementors + .entry(trait_.def_id()) + .or_default() + .push(Impl { impl_item: item.clone() }); + } + } + } + + // Index this method for searching later on. + if let Some(ref s) = item.name.or_else(|| { + if item.is_stripped() { + None + } else if let clean::ImportItem(ref i) = *item.kind && + let clean::ImportKind::Simple(s) = i.kind { + Some(s) + } else { + None + } + }) { + let (parent, is_inherent_impl_item) = match *item.kind { + clean::StrippedItem(..) => ((None, None), false), + clean::AssocConstItem(..) | clean::AssocTypeItem(..) + if self + .cache + .parent_stack + .last() + .map_or(false, |parent| parent.is_trait_impl()) => + { + // skip associated items in trait impls + ((None, None), false) + } + clean::TyMethodItem(..) + | clean::TyAssocConstItem(..) + | clean::TyAssocTypeItem(..) + | clean::StructFieldItem(..) + | clean::VariantItem(..) => ( + ( + Some( + self.cache + .parent_stack + .last() + .expect("parent_stack is empty") + .item_id() + .expect_def_id(), + ), + Some(&self.cache.stack[..self.cache.stack.len() - 1]), + ), + false, + ), + clean::MethodItem(..) | clean::AssocConstItem(..) | clean::AssocTypeItem(..) => { + if self.cache.parent_stack.is_empty() { + ((None, None), false) + } else { + let last = self.cache.parent_stack.last().expect("parent_stack is empty 2"); + let did = match &*last { + ParentStackItem::Impl { for_, .. } => for_.def_id(&self.cache), + ParentStackItem::Type(item_id) => item_id.as_def_id(), + }; + let path = match did.and_then(|did| self.cache.paths.get(&did)) { + // The current stack not necessarily has correlation + // for where the type was defined. On the other + // hand, `paths` always has the right + // information if present. + Some(&(ref fqp, _)) => Some(&fqp[..fqp.len() - 1]), + None => None, + }; + ((did, path), true) + } + } + _ => ((None, Some(&*self.cache.stack)), false), + }; + + match parent { + (parent, Some(path)) if is_inherent_impl_item || !self.cache.stripped_mod => { + debug_assert!(!item.is_stripped()); + + // A crate has a module at its root, containing all items, + // which should not be indexed. The crate-item itself is + // inserted later on when serializing the search-index. + if item.item_id.as_def_id().map_or(false, |idx| !idx.is_crate_root()) { + let desc = item.doc_value().map_or_else(String::new, |x| { + short_markdown_summary(x.as_str(), &item.link_names(self.cache)) + }); + self.cache.search_index.push(IndexItem { + ty: item.type_(), + name: s.to_string(), + path: join_with_double_colon(path), + desc, + parent, + parent_idx: None, + search_type: get_function_type_for_search( + &item, + self.tcx, + clean_impl_generics(self.cache.parent_stack.last()).as_ref(), + self.cache, + ), + aliases: item.attrs.get_doc_aliases(), + }); + } + } + (Some(parent), None) if is_inherent_impl_item => { + // We have a parent, but we don't know where they're + // defined yet. Wait for later to index this item. + let impl_generics = clean_impl_generics(self.cache.parent_stack.last()); + self.cache.orphan_impl_items.push(OrphanImplItem { + parent, + item: item.clone(), + impl_generics, + }); + } + _ => {} + } + } + + // Keep track of the fully qualified path for this item. + let pushed = match item.name { + Some(n) if !n.is_empty() => { + self.cache.stack.push(n); + true + } + _ => false, + }; + + match *item.kind { + clean::StructItem(..) + | clean::EnumItem(..) + | clean::TypedefItem(..) + | clean::TraitItem(..) + | clean::TraitAliasItem(..) + | clean::FunctionItem(..) + | clean::ModuleItem(..) + | clean::ForeignFunctionItem(..) + | clean::ForeignStaticItem(..) + | clean::ConstantItem(..) + | clean::StaticItem(..) + | clean::UnionItem(..) + | clean::ForeignTypeItem + | clean::MacroItem(..) + | clean::ProcMacroItem(..) + | clean::VariantItem(..) => { + if !self.cache.stripped_mod { + // Re-exported items mean that the same id can show up twice + // in the rustdoc ast that we're looking at. We know, + // however, that a re-exported item doesn't show up in the + // `public_items` map, so we can skip inserting into the + // paths map if there was already an entry present and we're + // not a public item. + if !self.cache.paths.contains_key(&item.item_id.expect_def_id()) + || self.cache.access_levels.is_public(item.item_id.expect_def_id()) + { + self.cache.paths.insert( + item.item_id.expect_def_id(), + (self.cache.stack.clone(), item.type_()), + ); + } + } + } + clean::PrimitiveItem(..) => { + self.cache + .paths + .insert(item.item_id.expect_def_id(), (self.cache.stack.clone(), item.type_())); + } + + clean::ExternCrateItem { .. } + | clean::ImportItem(..) + | clean::OpaqueTyItem(..) + | clean::ImplItem(..) + | clean::TyMethodItem(..) + | clean::MethodItem(..) + | clean::StructFieldItem(..) + | clean::TyAssocConstItem(..) + | clean::AssocConstItem(..) + | clean::TyAssocTypeItem(..) + | clean::AssocTypeItem(..) + | clean::StrippedItem(..) + | clean::KeywordItem => { + // FIXME: Do these need handling? + // The person writing this comment doesn't know. + // So would rather leave them to an expert, + // as at least the list is better than `_ => {}`. + } + } + + // Maintain the parent stack. + let (item, parent_pushed) = match *item.kind { + clean::TraitItem(..) + | clean::EnumItem(..) + | clean::ForeignTypeItem + | clean::StructItem(..) + | clean::UnionItem(..) + | clean::VariantItem(..) + | clean::ImplItem(..) => { + self.cache.parent_stack.push(ParentStackItem::new(&item)); + (self.fold_item_recur(item), true) + } + _ => (self.fold_item_recur(item), false), + }; + + // Once we've recursively found all the generics, hoard off all the + // implementations elsewhere. + let ret = if let clean::Item { kind: box clean::ImplItem(ref i), .. } = item { + // Figure out the id of this impl. This may map to a + // primitive rather than always to a struct/enum. + // Note: matching twice to restrict the lifetime of the `i` borrow. + let mut dids = FxHashSet::default(); + match i.for_ { + clean::Type::Path { ref path } + | clean::BorrowedRef { type_: box clean::Type::Path { ref path }, .. } => { + dids.insert(path.def_id()); + if let Some(generics) = path.generics() && + let ty::Adt(adt, _) = self.tcx.type_of(path.def_id()).kind() && + adt.is_fundamental() { + for ty in generics { + if let Some(did) = ty.def_id(self.cache) { + dids.insert(did); + } + } + } + } + clean::DynTrait(ref bounds, _) + | clean::BorrowedRef { type_: box clean::DynTrait(ref bounds, _), .. } => { + dids.insert(bounds[0].trait_.def_id()); + } + ref t => { + let did = t + .primitive_type() + .and_then(|t| self.cache.primitive_locations.get(&t).cloned()); + + if let Some(did) = did { + dids.insert(did); + } + } + } + + if let Some(generics) = i.trait_.as_ref().and_then(|t| t.generics()) { + for bound in generics { + if let Some(did) = bound.def_id(self.cache) { + dids.insert(did); + } + } + } + let impl_item = Impl { impl_item: item }; + if impl_item.trait_did().map_or(true, |d| self.cache.traits.contains_key(&d)) { + for did in dids { + if self.impl_ids.entry(did).or_default().insert(impl_item.def_id()) { + self.cache + .impls + .entry(did) + .or_insert_with(Vec::new) + .push(impl_item.clone()); + } + } + } else { + let trait_did = impl_item.trait_did().expect("no trait did"); + self.cache.orphan_trait_impls.push((trait_did, dids, impl_item)); + } + None + } else { + Some(item) + }; + + if pushed { + self.cache.stack.pop().expect("stack already empty"); + } + if parent_pushed { + self.cache.parent_stack.pop().expect("parent stack already empty"); + } + self.cache.stripped_mod = orig_stripped_mod; + ret + } +} + +pub(crate) struct OrphanImplItem { + pub(crate) parent: DefId, + pub(crate) item: clean::Item, + pub(crate) impl_generics: Option<(clean::Type, clean::Generics)>, +} + +/// Information about trait and type parents is tracked while traversing the item tree to build +/// the cache. +/// +/// We don't just store `Item` in there, because `Item` contains the list of children being +/// traversed and it would be wasteful to clone all that. We also need the item id, so just +/// storing `ItemKind` won't work, either. +enum ParentStackItem { + Impl { + for_: clean::Type, + trait_: Option, + generics: clean::Generics, + kind: clean::ImplKind, + item_id: ItemId, + }, + Type(ItemId), +} + +impl ParentStackItem { + fn new(item: &clean::Item) -> Self { + match &*item.kind { + clean::ItemKind::ImplItem(box clean::Impl { for_, trait_, generics, kind, .. }) => { + ParentStackItem::Impl { + for_: for_.clone(), + trait_: trait_.clone(), + generics: generics.clone(), + kind: kind.clone(), + item_id: item.item_id, + } + } + _ => ParentStackItem::Type(item.item_id), + } + } + fn is_trait_impl(&self) -> bool { + matches!(self, ParentStackItem::Impl { trait_: Some(..), .. }) + } + fn item_id(&self) -> ItemId { + match self { + ParentStackItem::Impl { item_id, .. } => *item_id, + ParentStackItem::Type(item_id) => *item_id, + } + } +} + +fn clean_impl_generics(item: Option<&ParentStackItem>) -> Option<(clean::Type, clean::Generics)> { + if let Some(ParentStackItem::Impl { for_, generics, kind: clean::ImplKind::Normal, .. }) = item + { + Some((for_.clone(), generics.clone())) + } else { + None + } +} diff --git a/src/librustdoc/formats/item_type.rs b/src/librustdoc/formats/item_type.rs new file mode 100644 index 000000000..0a7ee2005 --- /dev/null +++ b/src/librustdoc/formats/item_type.rs @@ -0,0 +1,185 @@ +//! Item types. + +use std::fmt; + +use serde::{Serialize, Serializer}; + +use rustc_hir::def::DefKind; +use rustc_span::hygiene::MacroKind; + +use crate::clean; + +/// Item type. Corresponds to `clean::ItemEnum` variants. +/// +/// The search index uses item types encoded as smaller numbers which equal to +/// discriminants. JavaScript then is used to decode them into the original value. +/// Consequently, every change to this type should be synchronized to +/// the `itemTypes` mapping table in `html/static/js/search.js`. +/// +/// In addition, code in `html::render` uses this enum to generate CSS classes, page prefixes, and +/// module headings. If you are adding to this enum and want to ensure that the sidebar also prints +/// a heading, edit the listing in `html/render.rs`, function `sidebar_module`. This uses an +/// ordering based on a helper function inside `item_module`, in the same file. +#[derive(Copy, PartialEq, Eq, Hash, Clone, Debug, PartialOrd, Ord)] +pub(crate) enum ItemType { + Module = 0, + ExternCrate = 1, + Import = 2, + Struct = 3, + Enum = 4, + Function = 5, + Typedef = 6, + Static = 7, + Trait = 8, + Impl = 9, + TyMethod = 10, + Method = 11, + StructField = 12, + Variant = 13, + Macro = 14, + Primitive = 15, + AssocType = 16, + Constant = 17, + AssocConst = 18, + Union = 19, + ForeignType = 20, + Keyword = 21, + OpaqueTy = 22, + ProcAttribute = 23, + ProcDerive = 24, + TraitAlias = 25, +} + +impl Serialize for ItemType { + fn serialize(&self, serializer: S) -> Result + where + S: Serializer, + { + (*self as u8).serialize(serializer) + } +} + +impl<'a> From<&'a clean::Item> for ItemType { + fn from(item: &'a clean::Item) -> ItemType { + let kind = match *item.kind { + clean::StrippedItem(box ref item) => item, + ref kind => kind, + }; + + match *kind { + clean::ModuleItem(..) => ItemType::Module, + clean::ExternCrateItem { .. } => ItemType::ExternCrate, + clean::ImportItem(..) => ItemType::Import, + clean::StructItem(..) => ItemType::Struct, + clean::UnionItem(..) => ItemType::Union, + clean::EnumItem(..) => ItemType::Enum, + clean::FunctionItem(..) => ItemType::Function, + clean::TypedefItem(..) => ItemType::Typedef, + clean::OpaqueTyItem(..) => ItemType::OpaqueTy, + clean::StaticItem(..) => ItemType::Static, + clean::ConstantItem(..) => ItemType::Constant, + clean::TraitItem(..) => ItemType::Trait, + clean::ImplItem(..) => ItemType::Impl, + clean::TyMethodItem(..) => ItemType::TyMethod, + clean::MethodItem(..) => ItemType::Method, + clean::StructFieldItem(..) => ItemType::StructField, + clean::VariantItem(..) => ItemType::Variant, + clean::ForeignFunctionItem(..) => ItemType::Function, // no ForeignFunction + clean::ForeignStaticItem(..) => ItemType::Static, // no ForeignStatic + clean::MacroItem(..) => ItemType::Macro, + clean::PrimitiveItem(..) => ItemType::Primitive, + clean::TyAssocConstItem(..) | clean::AssocConstItem(..) => ItemType::AssocConst, + clean::TyAssocTypeItem(..) | clean::AssocTypeItem(..) => ItemType::AssocType, + clean::ForeignTypeItem => ItemType::ForeignType, + clean::KeywordItem => ItemType::Keyword, + clean::TraitAliasItem(..) => ItemType::TraitAlias, + clean::ProcMacroItem(ref mac) => match mac.kind { + MacroKind::Bang => ItemType::Macro, + MacroKind::Attr => ItemType::ProcAttribute, + MacroKind::Derive => ItemType::ProcDerive, + }, + clean::StrippedItem(..) => unreachable!(), + } + } +} + +impl From for ItemType { + fn from(other: DefKind) -> Self { + match other { + DefKind::Enum => Self::Enum, + DefKind::Fn => Self::Function, + DefKind::Mod => Self::Module, + DefKind::Const => Self::Constant, + DefKind::Static(_) => Self::Static, + DefKind::Struct => Self::Struct, + DefKind::Union => Self::Union, + DefKind::Trait => Self::Trait, + DefKind::TyAlias => Self::Typedef, + DefKind::TraitAlias => Self::TraitAlias, + DefKind::Macro(kind) => match kind { + MacroKind::Bang => ItemType::Macro, + MacroKind::Attr => ItemType::ProcAttribute, + MacroKind::Derive => ItemType::ProcDerive, + }, + DefKind::ForeignTy + | DefKind::Variant + | DefKind::AssocTy + | DefKind::TyParam + | DefKind::ConstParam + | DefKind::Ctor(..) + | DefKind::AssocFn + | DefKind::AssocConst + | DefKind::ExternCrate + | DefKind::Use + | DefKind::ForeignMod + | DefKind::AnonConst + | DefKind::InlineConst + | DefKind::OpaqueTy + | DefKind::Field + | DefKind::LifetimeParam + | DefKind::GlobalAsm + | DefKind::Impl + | DefKind::Closure + | DefKind::Generator => Self::ForeignType, + } + } +} + +impl ItemType { + pub(crate) fn as_str(&self) -> &'static str { + match *self { + ItemType::Module => "mod", + ItemType::ExternCrate => "externcrate", + ItemType::Import => "import", + ItemType::Struct => "struct", + ItemType::Union => "union", + ItemType::Enum => "enum", + ItemType::Function => "fn", + ItemType::Typedef => "type", + ItemType::Static => "static", + ItemType::Trait => "trait", + ItemType::Impl => "impl", + ItemType::TyMethod => "tymethod", + ItemType::Method => "method", + ItemType::StructField => "structfield", + ItemType::Variant => "variant", + ItemType::Macro => "macro", + ItemType::Primitive => "primitive", + ItemType::AssocType => "associatedtype", + ItemType::Constant => "constant", + ItemType::AssocConst => "associatedconstant", + ItemType::ForeignType => "foreigntype", + ItemType::Keyword => "keyword", + ItemType::OpaqueTy => "opaque", + ItemType::ProcAttribute => "attr", + ItemType::ProcDerive => "derive", + ItemType::TraitAlias => "traitalias", + } + } +} + +impl fmt::Display for ItemType { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.write_str(self.as_str()) + } +} diff --git a/src/librustdoc/formats/mod.rs b/src/librustdoc/formats/mod.rs new file mode 100644 index 000000000..b236bd7be --- /dev/null +++ b/src/librustdoc/formats/mod.rs @@ -0,0 +1,101 @@ +pub(crate) mod cache; +pub(crate) mod item_type; +pub(crate) mod renderer; + +use rustc_hir::def_id::DefId; + +pub(crate) use renderer::{run_format, FormatRenderer}; + +use crate::clean::{self, ItemId}; +use crate::html::render::Context; + +/// Specifies whether rendering directly implemented trait items or ones from a certain Deref +/// impl. +pub(crate) enum AssocItemRender<'a> { + All, + DerefFor { trait_: &'a clean::Path, type_: &'a clean::Type, deref_mut_: bool }, +} + +/// For different handling of associated items from the Deref target of a type rather than the type +/// itself. +#[derive(Copy, Clone, PartialEq)] +pub(crate) enum RenderMode { + Normal, + ForDeref { mut_: bool }, +} + +/// Metadata about implementations for a type or trait. +#[derive(Clone, Debug)] +pub(crate) struct Impl { + pub(crate) impl_item: clean::Item, +} + +impl Impl { + pub(crate) fn inner_impl(&self) -> &clean::Impl { + match *self.impl_item.kind { + clean::ImplItem(ref impl_) => impl_, + _ => panic!("non-impl item found in impl"), + } + } + + pub(crate) fn trait_did(&self) -> Option { + self.inner_impl().trait_.as_ref().map(|t| t.def_id()) + } + + /// This function is used to extract a `DefId` to be used as a key for the `Cache::impls` field. + /// + /// It allows to prevent having duplicated implementations showing up (the biggest issue was + /// with blanket impls). + /// + /// It panics if `self` is a `ItemId::Primitive`. + pub(crate) fn def_id(&self) -> DefId { + match self.impl_item.item_id { + ItemId::Blanket { impl_id, .. } => impl_id, + ItemId::Auto { trait_, .. } => trait_, + ItemId::DefId(def_id) => def_id, + ItemId::Primitive(_, _) => { + panic!( + "Unexpected ItemId::Primitive in expect_def_id: {:?}", + self.impl_item.item_id + ) + } + } + } + + // Returns true if this is an implementation on a "local" type, meaning: + // the type is in the current crate, or the type and the trait are both + // re-exported by the current crate. + pub(crate) fn is_on_local_type(&self, cx: &Context<'_>) -> bool { + let cache = cx.cache(); + let for_type = &self.inner_impl().for_; + if let Some(for_type_did) = for_type.def_id(cache) { + // The "for" type is local if it's in the paths for the current crate. + if cache.paths.contains_key(&for_type_did) { + return true; + } + if let Some(trait_did) = self.trait_did() { + // The "for" type and the trait are from the same crate. That could + // be different from the current crate, for instance when both were + // re-exported from some other crate. But they are local with respect to + // each other. + if for_type_did.krate == trait_did.krate { + return true; + } + // Hack: many traits and types in std are re-exported from + // core or alloc. In general, rustdoc is capable of recognizing + // these implementations as being on local types. However, in at + // least one case (https://github.com/rust-lang/rust/issues/97610), + // rustdoc gets confused and labels an implementation as being on + // a foreign type. To make sure that confusion doesn't pass on to + // the reader, consider all implementations in std, core, and alloc + // to be on local types. + let crate_name = cx.tcx().crate_name(trait_did.krate); + if matches!(crate_name.as_str(), "std" | "core" | "alloc") { + return true; + } + } + return false; + }; + true + } +} diff --git a/src/librustdoc/formats/renderer.rs b/src/librustdoc/formats/renderer.rs new file mode 100644 index 000000000..62ba984ac --- /dev/null +++ b/src/librustdoc/formats/renderer.rs @@ -0,0 +1,97 @@ +use rustc_middle::ty::TyCtxt; +use rustc_span::Symbol; + +use crate::clean; +use crate::config::RenderOptions; +use crate::error::Error; +use crate::formats::cache::Cache; + +/// Allows for different backends to rustdoc to be used with the `run_format()` function. Each +/// backend renderer has hooks for initialization, documenting an item, entering and exiting a +/// module, and cleanup/finalizing output. +pub(crate) trait FormatRenderer<'tcx>: Sized { + /// Gives a description of the renderer. Used for performance profiling. + fn descr() -> &'static str; + + /// Whether to call `item` recursively for modules + /// + /// This is true for html, and false for json. See #80664 + const RUN_ON_MODULE: bool; + + /// Sets up any state required for the renderer. When this is called the cache has already been + /// populated. + fn init( + krate: clean::Crate, + options: RenderOptions, + cache: Cache, + tcx: TyCtxt<'tcx>, + ) -> Result<(Self, clean::Crate), Error>; + + /// Make a new renderer to render a child of the item currently being rendered. + fn make_child_renderer(&self) -> Self; + + /// Renders a single non-module item. This means no recursive sub-item rendering is required. + fn item(&mut self, item: clean::Item) -> Result<(), Error>; + + /// Renders a module (should not handle recursing into children). + fn mod_item_in(&mut self, item: &clean::Item) -> Result<(), Error>; + + /// Runs after recursively rendering all sub-items of a module. + fn mod_item_out(&mut self) -> Result<(), Error> { + Ok(()) + } + + /// Post processing hook for cleanup and dumping output to files. + fn after_krate(&mut self) -> Result<(), Error>; + + fn cache(&self) -> &Cache; +} + +/// Main method for rendering a crate. +pub(crate) fn run_format<'tcx, T: FormatRenderer<'tcx>>( + krate: clean::Crate, + options: RenderOptions, + cache: Cache, + tcx: TyCtxt<'tcx>, +) -> Result<(), Error> { + let prof = &tcx.sess.prof; + + let emit_crate = options.should_emit_crate(); + let (mut format_renderer, krate) = prof + .extra_verbose_generic_activity("create_renderer", T::descr()) + .run(|| T::init(krate, options, cache, tcx))?; + + if !emit_crate { + return Ok(()); + } + + // Render the crate documentation + let mut work = vec![(format_renderer.make_child_renderer(), krate.module)]; + + let unknown = Symbol::intern(""); + while let Some((mut cx, item)) = work.pop() { + if item.is_mod() && T::RUN_ON_MODULE { + // modules are special because they add a namespace. We also need to + // recurse into the items of the module as well. + let _timer = + prof.generic_activity_with_arg("render_mod_item", item.name.unwrap().to_string()); + + cx.mod_item_in(&item)?; + let (clean::StrippedItem(box clean::ModuleItem(module)) | clean::ModuleItem(module)) = *item.kind + else { unreachable!() }; + for it in module.items { + debug!("Adding {:?} to worklist", it.name); + work.push((cx.make_child_renderer(), it)); + } + + cx.mod_item_out()?; + // FIXME: checking `item.name.is_some()` is very implicit and leads to lots of special + // cases. Use an explicit match instead. + } else if item.name.is_some() && !item.is_extern_crate() { + prof.generic_activity_with_arg("render_item", item.name.unwrap_or(unknown).as_str()) + .run(|| cx.item(item))?; + } + } + prof.extra_verbose_generic_activity("renderer_after_krate", T::descr()) + .run(|| format_renderer.after_krate()) +} diff --git a/src/librustdoc/html/escape.rs b/src/librustdoc/html/escape.rs new file mode 100644 index 000000000..4a19d0a44 --- /dev/null +++ b/src/librustdoc/html/escape.rs @@ -0,0 +1,40 @@ +//! HTML escaping. +//! +//! This module contains one unit struct, which can be used to HTML-escape a +//! string of text (for use in a format string). + +use std::fmt; + +/// Wrapper struct which will emit the HTML-escaped version of the contained +/// string when passed to a format string. +pub(crate) struct Escape<'a>(pub &'a str); + +impl<'a> fmt::Display for Escape<'a> { + fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { + // Because the internet is always right, turns out there's not that many + // characters to escape: http://stackoverflow.com/questions/7381974 + let Escape(s) = *self; + let pile_o_bits = s; + let mut last = 0; + for (i, ch) in s.char_indices() { + let s = match ch { + '>' => ">", + '<' => "<", + '&' => "&", + '\'' => "'", + '"' => """, + _ => continue, + }; + fmt.write_str(&pile_o_bits[last..i])?; + fmt.write_str(s)?; + // NOTE: we only expect single byte characters here - which is fine as long as we + // only match single byte characters + last = i + 1; + } + + if last < s.len() { + fmt.write_str(&pile_o_bits[last..])?; + } + Ok(()) + } +} diff --git a/src/librustdoc/html/format.rs b/src/librustdoc/html/format.rs new file mode 100644 index 000000000..36a47b05c --- /dev/null +++ b/src/librustdoc/html/format.rs @@ -0,0 +1,1688 @@ +//! HTML formatting module +//! +//! This module contains a large number of `fmt::Display` implementations for +//! various types in `rustdoc::clean`. These implementations all currently +//! assume that HTML output is desired, although it may be possible to redesign +//! them in the future to instead emit any format desired. + +use std::borrow::Cow; +use std::cell::Cell; +use std::fmt; +use std::iter::{self, once}; + +use rustc_ast as ast; +use rustc_attr::{ConstStability, StabilityLevel}; +use rustc_data_structures::captures::Captures; +use rustc_data_structures::fx::FxHashSet; +use rustc_hir as hir; +use rustc_hir::def::DefKind; +use rustc_hir::def_id::DefId; +use rustc_metadata::creader::{CStore, LoadedMacro}; +use rustc_middle::ty; +use rustc_middle::ty::DefIdTree; +use rustc_middle::ty::TyCtxt; +use rustc_span::symbol::kw; +use rustc_span::{sym, Symbol}; +use rustc_target::spec::abi::Abi; + +use itertools::Itertools; + +use crate::clean::{ + self, types::ExternalLocation, utils::find_nearest_parent_module, ExternalCrate, ItemId, + PrimitiveType, +}; +use crate::formats::item_type::ItemType; +use crate::html::escape::Escape; +use crate::html::render::Context; + +use super::url_parts_builder::estimate_item_path_byte_length; +use super::url_parts_builder::UrlPartsBuilder; + +pub(crate) trait Print { + fn print(self, buffer: &mut Buffer); +} + +impl Print for F +where + F: FnOnce(&mut Buffer), +{ + fn print(self, buffer: &mut Buffer) { + (self)(buffer) + } +} + +impl Print for String { + fn print(self, buffer: &mut Buffer) { + buffer.write_str(&self); + } +} + +impl Print for &'_ str { + fn print(self, buffer: &mut Buffer) { + buffer.write_str(self); + } +} + +#[derive(Debug, Clone)] +pub(crate) struct Buffer { + for_html: bool, + buffer: String, +} + +impl core::fmt::Write for Buffer { + #[inline] + fn write_str(&mut self, s: &str) -> fmt::Result { + self.buffer.write_str(s) + } + + #[inline] + fn write_char(&mut self, c: char) -> fmt::Result { + self.buffer.write_char(c) + } + + #[inline] + fn write_fmt(&mut self, args: fmt::Arguments<'_>) -> fmt::Result { + self.buffer.write_fmt(args) + } +} + +impl Buffer { + pub(crate) fn empty_from(v: &Buffer) -> Buffer { + Buffer { for_html: v.for_html, buffer: String::new() } + } + + pub(crate) fn html() -> Buffer { + Buffer { for_html: true, buffer: String::new() } + } + + pub(crate) fn new() -> Buffer { + Buffer { for_html: false, buffer: String::new() } + } + + pub(crate) fn is_empty(&self) -> bool { + self.buffer.is_empty() + } + + pub(crate) fn into_inner(self) -> String { + self.buffer + } + + pub(crate) fn insert_str(&mut self, idx: usize, s: &str) { + self.buffer.insert_str(idx, s); + } + + pub(crate) fn push_str(&mut self, s: &str) { + self.buffer.push_str(s); + } + + pub(crate) fn push_buffer(&mut self, other: Buffer) { + self.buffer.push_str(&other.buffer); + } + + // Intended for consumption by write! and writeln! (std::fmt) but without + // the fmt::Result return type imposed by fmt::Write (and avoiding the trait + // import). + pub(crate) fn write_str(&mut self, s: &str) { + self.buffer.push_str(s); + } + + // Intended for consumption by write! and writeln! (std::fmt) but without + // the fmt::Result return type imposed by fmt::Write (and avoiding the trait + // import). + pub(crate) fn write_fmt(&mut self, v: fmt::Arguments<'_>) { + use fmt::Write; + self.buffer.write_fmt(v).unwrap(); + } + + pub(crate) fn to_display(mut self, t: T) -> String { + t.print(&mut self); + self.into_inner() + } + + pub(crate) fn is_for_html(&self) -> bool { + self.for_html + } + + pub(crate) fn reserve(&mut self, additional: usize) { + self.buffer.reserve(additional) + } + + pub(crate) fn len(&self) -> usize { + self.buffer.len() + } +} + +fn comma_sep( + items: impl Iterator, + space_after_comma: bool, +) -> impl fmt::Display { + display_fn(move |f| { + for (i, item) in items.enumerate() { + if i != 0 { + write!(f, ",{}", if space_after_comma { " " } else { "" })?; + } + fmt::Display::fmt(&item, f)?; + } + Ok(()) + }) +} + +pub(crate) fn print_generic_bounds<'a, 'tcx: 'a>( + bounds: &'a [clean::GenericBound], + cx: &'a Context<'tcx>, +) -> impl fmt::Display + 'a + Captures<'tcx> { + display_fn(move |f| { + let mut bounds_dup = FxHashSet::default(); + + for (i, bound) in bounds.iter().filter(|b| bounds_dup.insert(b.clone())).enumerate() { + if i > 0 { + f.write_str(" + ")?; + } + fmt::Display::fmt(&bound.print(cx), f)?; + } + Ok(()) + }) +} + +impl clean::GenericParamDef { + pub(crate) fn print<'a, 'tcx: 'a>( + &'a self, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'a + Captures<'tcx> { + display_fn(move |f| match &self.kind { + clean::GenericParamDefKind::Lifetime { outlives } => { + write!(f, "{}", self.name)?; + + if !outlives.is_empty() { + f.write_str(": ")?; + for (i, lt) in outlives.iter().enumerate() { + if i != 0 { + f.write_str(" + ")?; + } + write!(f, "{}", lt.print())?; + } + } + + Ok(()) + } + clean::GenericParamDefKind::Type { bounds, default, .. } => { + f.write_str(self.name.as_str())?; + + if !bounds.is_empty() { + if f.alternate() { + write!(f, ": {:#}", print_generic_bounds(bounds, cx))?; + } else { + write!(f, ": {}", print_generic_bounds(bounds, cx))?; + } + } + + if let Some(ref ty) = default { + if f.alternate() { + write!(f, " = {:#}", ty.print(cx))?; + } else { + write!(f, " = {}", ty.print(cx))?; + } + } + + Ok(()) + } + clean::GenericParamDefKind::Const { ty, default, .. } => { + if f.alternate() { + write!(f, "const {}: {:#}", self.name, ty.print(cx))?; + } else { + write!(f, "const {}: {}", self.name, ty.print(cx))?; + } + + if let Some(default) = default { + if f.alternate() { + write!(f, " = {:#}", default)?; + } else { + write!(f, " = {}", default)?; + } + } + + Ok(()) + } + }) + } +} + +impl clean::Generics { + pub(crate) fn print<'a, 'tcx: 'a>( + &'a self, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'a + Captures<'tcx> { + display_fn(move |f| { + let mut real_params = + self.params.iter().filter(|p| !p.is_synthetic_type_param()).peekable(); + if real_params.peek().is_none() { + return Ok(()); + } + + if f.alternate() { + write!(f, "<{:#}>", comma_sep(real_params.map(|g| g.print(cx)), true)) + } else { + write!(f, "<{}>", comma_sep(real_params.map(|g| g.print(cx)), true)) + } + }) + } +} + +#[derive(Clone, Copy, PartialEq, Eq)] +pub(crate) enum Ending { + Newline, + NoNewline, +} + +/// * The Generics from which to emit a where-clause. +/// * The number of spaces to indent each line with. +/// * Whether the where-clause needs to add a comma and newline after the last bound. +pub(crate) fn print_where_clause<'a, 'tcx: 'a>( + gens: &'a clean::Generics, + cx: &'a Context<'tcx>, + indent: usize, + ending: Ending, +) -> impl fmt::Display + 'a + Captures<'tcx> { + use fmt::Write; + + display_fn(move |f| { + let mut where_predicates = gens.where_predicates.iter().filter(|pred| { + !matches!(pred, clean::WherePredicate::BoundPredicate { bounds, .. } if bounds.is_empty()) + }).map(|pred| { + display_fn(move |f| { + if f.alternate() { + f.write_str(" ")?; + } else { + f.write_str("
")?; + } + + match pred { + clean::WherePredicate::BoundPredicate { ty, bounds, bound_params } => { + let ty_cx = ty.print(cx); + let generic_bounds = print_generic_bounds(bounds, cx); + + if bound_params.is_empty() { + if f.alternate() { + write!(f, "{ty_cx:#}: {generic_bounds:#}") + } else { + write!(f, "{ty_cx}: {generic_bounds}") + } + } else { + if f.alternate() { + write!( + f, + "for<{:#}> {ty_cx:#}: {generic_bounds:#}", + comma_sep(bound_params.iter().map(|lt| lt.print()), true) + ) + } else { + write!( + f, + "for<{}> {ty_cx}: {generic_bounds}", + comma_sep(bound_params.iter().map(|lt| lt.print()), true) + ) + } + } + } + clean::WherePredicate::RegionPredicate { lifetime, bounds } => { + let mut bounds_display = String::new(); + for bound in bounds.iter().map(|b| b.print(cx)) { + write!(bounds_display, "{bound} + ")?; + } + bounds_display.truncate(bounds_display.len() - " + ".len()); + write!(f, "{}: {bounds_display}", lifetime.print()) + } + clean::WherePredicate::EqPredicate { lhs, rhs } => { + if f.alternate() { + write!(f, "{:#} == {:#}", lhs.print(cx), rhs.print(cx)) + } else { + write!(f, "{} == {}", lhs.print(cx), rhs.print(cx)) + } + } + } + }) + }).peekable(); + + if where_predicates.peek().is_none() { + return Ok(()); + } + + let where_preds = comma_sep(where_predicates, false); + let clause = if f.alternate() { + if ending == Ending::Newline { + // add a space so stripping
tags and breaking spaces still renders properly + format!(" where{where_preds}, ") + } else { + format!(" where{where_preds}") + } + } else { + let mut br_with_padding = String::with_capacity(6 * indent + 28); + br_with_padding.push_str("
"); + for _ in 0..indent + 4 { + br_with_padding.push_str(" "); + } + let where_preds = where_preds.to_string().replace("
", &br_with_padding); + + if ending == Ending::Newline { + let mut clause = " ".repeat(indent.saturating_sub(1)); + // add a space so stripping
tags and breaking spaces still renders properly + write!( + clause, + " where{where_preds}, " + )?; + clause + } else { + // insert a
tag after a single space but before multiple spaces at the start + if indent == 0 { + format!("
where{where_preds}") + } else { + let mut clause = br_with_padding; + clause.truncate(clause.len() - 5 * " ".len()); + write!(clause, " where{where_preds}")?; + clause + } + } + }; + write!(f, "{clause}") + }) +} + +impl clean::Lifetime { + pub(crate) fn print(&self) -> impl fmt::Display + '_ { + self.0.as_str() + } +} + +impl clean::Constant { + pub(crate) fn print(&self, tcx: TyCtxt<'_>) -> impl fmt::Display + '_ { + let expr = self.expr(tcx); + display_fn( + move |f| { + if f.alternate() { f.write_str(&expr) } else { write!(f, "{}", Escape(&expr)) } + }, + ) + } +} + +impl clean::PolyTrait { + fn print<'a, 'tcx: 'a>( + &'a self, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'a + Captures<'tcx> { + display_fn(move |f| { + if !self.generic_params.is_empty() { + if f.alternate() { + write!( + f, + "for<{:#}> ", + comma_sep(self.generic_params.iter().map(|g| g.print(cx)), true) + )?; + } else { + write!( + f, + "for<{}> ", + comma_sep(self.generic_params.iter().map(|g| g.print(cx)), true) + )?; + } + } + if f.alternate() { + write!(f, "{:#}", self.trait_.print(cx)) + } else { + write!(f, "{}", self.trait_.print(cx)) + } + }) + } +} + +impl clean::GenericBound { + pub(crate) fn print<'a, 'tcx: 'a>( + &'a self, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'a + Captures<'tcx> { + display_fn(move |f| match self { + clean::GenericBound::Outlives(lt) => write!(f, "{}", lt.print()), + clean::GenericBound::TraitBound(ty, modifier) => { + let modifier_str = match modifier { + hir::TraitBoundModifier::None => "", + hir::TraitBoundModifier::Maybe => "?", + // ~const is experimental; do not display those bounds in rustdoc + hir::TraitBoundModifier::MaybeConst => "", + }; + if f.alternate() { + write!(f, "{}{:#}", modifier_str, ty.print(cx)) + } else { + write!(f, "{}{}", modifier_str, ty.print(cx)) + } + } + }) + } +} + +impl clean::GenericArgs { + fn print<'a, 'tcx: 'a>( + &'a self, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'a + Captures<'tcx> { + display_fn(move |f| { + match self { + clean::GenericArgs::AngleBracketed { args, bindings } => { + if !args.is_empty() || !bindings.is_empty() { + if f.alternate() { + f.write_str("<")?; + } else { + f.write_str("<")?; + } + let mut comma = false; + for arg in args.iter() { + if comma { + f.write_str(", ")?; + } + comma = true; + if f.alternate() { + write!(f, "{:#}", arg.print(cx))?; + } else { + write!(f, "{}", arg.print(cx))?; + } + } + for binding in bindings.iter() { + if comma { + f.write_str(", ")?; + } + comma = true; + if f.alternate() { + write!(f, "{:#}", binding.print(cx))?; + } else { + write!(f, "{}", binding.print(cx))?; + } + } + if f.alternate() { + f.write_str(">")?; + } else { + f.write_str(">")?; + } + } + } + clean::GenericArgs::Parenthesized { inputs, output } => { + f.write_str("(")?; + let mut comma = false; + for ty in inputs.iter() { + if comma { + f.write_str(", ")?; + } + comma = true; + if f.alternate() { + write!(f, "{:#}", ty.print(cx))?; + } else { + write!(f, "{}", ty.print(cx))?; + } + } + f.write_str(")")?; + if let Some(ref ty) = *output { + if f.alternate() { + write!(f, " -> {:#}", ty.print(cx))?; + } else { + write!(f, " -> {}", ty.print(cx))?; + } + } + } + } + Ok(()) + }) + } +} + +// Possible errors when computing href link source for a `DefId` +#[derive(PartialEq, Eq)] +pub(crate) enum HrefError { + /// This item is known to rustdoc, but from a crate that does not have documentation generated. + /// + /// This can only happen for non-local items. + /// + /// # Example + /// + /// Crate `a` defines a public trait and crate `b` – the target crate that depends on `a` – + /// implements it for a local type. + /// We document `b` but **not** `a` (we only _build_ the latter – with `rustc`): + /// + /// ```sh + /// rustc a.rs --crate-type=lib + /// rustdoc b.rs --crate-type=lib --extern=a=liba.rlib + /// ``` + /// + /// Now, the associated items in the trait impl want to link to the corresponding item in the + /// trait declaration (see `html::render::assoc_href_attr`) but it's not available since their + /// *documentation (was) not built*. + DocumentationNotBuilt, + /// This can only happen for non-local items when `--document-private-items` is not passed. + Private, + // Not in external cache, href link should be in same page + NotInExternalCache, +} + +// Panics if `syms` is empty. +pub(crate) fn join_with_double_colon(syms: &[Symbol]) -> String { + let mut s = String::with_capacity(estimate_item_path_byte_length(syms.len())); + s.push_str(syms[0].as_str()); + for sym in &syms[1..] { + s.push_str("::"); + s.push_str(sym.as_str()); + } + s +} + +/// This function is to get the external macro path because they are not in the cache used in +/// `href_with_root_path`. +fn generate_macro_def_id_path( + def_id: DefId, + cx: &Context<'_>, + root_path: Option<&str>, +) -> Result<(String, ItemType, Vec), HrefError> { + let tcx = cx.shared.tcx; + let crate_name = tcx.crate_name(def_id.krate).to_string(); + let cache = cx.cache(); + + let fqp: Vec = tcx + .def_path(def_id) + .data + .into_iter() + .filter_map(|elem| { + // extern blocks (and a few others things) have an empty name. + match elem.data.get_opt_name() { + Some(s) if !s.is_empty() => Some(s), + _ => None, + } + }) + .collect(); + let relative = fqp.iter().map(|elem| elem.to_string()); + let cstore = CStore::from_tcx(tcx); + // We need this to prevent a `panic` when this function is used from intra doc links... + if !cstore.has_crate_data(def_id.krate) { + debug!("No data for crate {}", crate_name); + return Err(HrefError::NotInExternalCache); + } + // Check to see if it is a macro 2.0 or built-in macro. + // More information in . + let is_macro_2 = match cstore.load_macro_untracked(def_id, tcx.sess) { + LoadedMacro::MacroDef(def, _) => { + // If `ast_def.macro_rules` is `true`, then it's not a macro 2.0. + matches!(&def.kind, ast::ItemKind::MacroDef(ast_def) if !ast_def.macro_rules) + } + _ => false, + }; + + let mut path = if is_macro_2 { + once(crate_name.clone()).chain(relative).collect() + } else { + vec![crate_name.clone(), relative.last().unwrap()] + }; + if path.len() < 2 { + // The minimum we can have is the crate name followed by the macro name. If shorter, then + // it means that that `relative` was empty, which is an error. + debug!("macro path cannot be empty!"); + return Err(HrefError::NotInExternalCache); + } + + if let Some(last) = path.last_mut() { + *last = format!("macro.{}.html", last); + } + + let url = match cache.extern_locations[&def_id.krate] { + ExternalLocation::Remote(ref s) => { + // `ExternalLocation::Remote` always end with a `/`. + format!("{}{}", s, path.join("/")) + } + ExternalLocation::Local => { + // `root_path` always end with a `/`. + format!("{}{}/{}", root_path.unwrap_or(""), crate_name, path.join("/")) + } + ExternalLocation::Unknown => { + debug!("crate {} not in cache when linkifying macros", crate_name); + return Err(HrefError::NotInExternalCache); + } + }; + Ok((url, ItemType::Macro, fqp)) +} + +pub(crate) fn href_with_root_path( + did: DefId, + cx: &Context<'_>, + root_path: Option<&str>, +) -> Result<(String, ItemType, Vec), HrefError> { + let tcx = cx.tcx(); + let def_kind = tcx.def_kind(did); + let did = match def_kind { + DefKind::AssocTy | DefKind::AssocFn | DefKind::AssocConst | DefKind::Variant => { + // documented on their parent's page + tcx.parent(did) + } + _ => did, + }; + let cache = cx.cache(); + let relative_to = &cx.current; + fn to_module_fqp(shortty: ItemType, fqp: &[Symbol]) -> &[Symbol] { + if shortty == ItemType::Module { fqp } else { &fqp[..fqp.len() - 1] } + } + + if !did.is_local() + && !cache.access_levels.is_public(did) + && !cache.document_private + && !cache.primitive_locations.values().any(|&id| id == did) + { + return Err(HrefError::Private); + } + + let mut is_remote = false; + let (fqp, shortty, mut url_parts) = match cache.paths.get(&did) { + Some(&(ref fqp, shortty)) => (fqp, shortty, { + let module_fqp = to_module_fqp(shortty, fqp.as_slice()); + debug!(?fqp, ?shortty, ?module_fqp); + href_relative_parts(module_fqp, relative_to).collect() + }), + None => { + if let Some(&(ref fqp, shortty)) = cache.external_paths.get(&did) { + let module_fqp = to_module_fqp(shortty, fqp); + ( + fqp, + shortty, + match cache.extern_locations[&did.krate] { + ExternalLocation::Remote(ref s) => { + is_remote = true; + let s = s.trim_end_matches('/'); + let mut builder = UrlPartsBuilder::singleton(s); + builder.extend(module_fqp.iter().copied()); + builder + } + ExternalLocation::Local => { + href_relative_parts(module_fqp, relative_to).collect() + } + ExternalLocation::Unknown => return Err(HrefError::DocumentationNotBuilt), + }, + ) + } else if matches!(def_kind, DefKind::Macro(_)) { + return generate_macro_def_id_path(did, cx, root_path); + } else { + return Err(HrefError::NotInExternalCache); + } + } + }; + if !is_remote { + if let Some(root_path) = root_path { + let root = root_path.trim_end_matches('/'); + url_parts.push_front(root); + } + } + debug!(?url_parts); + match shortty { + ItemType::Module => { + url_parts.push("index.html"); + } + _ => { + let prefix = shortty.as_str(); + let last = fqp.last().unwrap(); + url_parts.push_fmt(format_args!("{}.{}.html", prefix, last)); + } + } + Ok((url_parts.finish(), shortty, fqp.to_vec())) +} + +pub(crate) fn href( + did: DefId, + cx: &Context<'_>, +) -> Result<(String, ItemType, Vec), HrefError> { + href_with_root_path(did, cx, None) +} + +/// Both paths should only be modules. +/// This is because modules get their own directories; that is, `std::vec` and `std::vec::Vec` will +/// both need `../iter/trait.Iterator.html` to get at the iterator trait. +pub(crate) fn href_relative_parts<'fqp>( + fqp: &'fqp [Symbol], + relative_to_fqp: &[Symbol], +) -> Box + 'fqp> { + for (i, (f, r)) in fqp.iter().zip(relative_to_fqp.iter()).enumerate() { + // e.g. linking to std::iter from std::vec (`dissimilar_part_count` will be 1) + if f != r { + let dissimilar_part_count = relative_to_fqp.len() - i; + let fqp_module = &fqp[i..fqp.len()]; + return Box::new( + iter::repeat(sym::dotdot) + .take(dissimilar_part_count) + .chain(fqp_module.iter().copied()), + ); + } + } + // e.g. linking to std::sync::atomic from std::sync + if relative_to_fqp.len() < fqp.len() { + Box::new(fqp[relative_to_fqp.len()..fqp.len()].iter().copied()) + // e.g. linking to std::sync from std::sync::atomic + } else if fqp.len() < relative_to_fqp.len() { + let dissimilar_part_count = relative_to_fqp.len() - fqp.len(); + Box::new(iter::repeat(sym::dotdot).take(dissimilar_part_count)) + // linking to the same module + } else { + Box::new(iter::empty()) + } +} + +/// Used to render a [`clean::Path`]. +fn resolved_path<'cx>( + w: &mut fmt::Formatter<'_>, + did: DefId, + path: &clean::Path, + print_all: bool, + use_absolute: bool, + cx: &'cx Context<'_>, +) -> fmt::Result { + let last = path.segments.last().unwrap(); + + if print_all { + for seg in &path.segments[..path.segments.len() - 1] { + write!(w, "{}::", if seg.name == kw::PathRoot { "" } else { seg.name.as_str() })?; + } + } + if w.alternate() { + write!(w, "{}{:#}", &last.name, last.args.print(cx))?; + } else { + let path = if use_absolute { + if let Ok((_, _, fqp)) = href(did, cx) { + format!( + "{}::{}", + join_with_double_colon(&fqp[..fqp.len() - 1]), + anchor(did, *fqp.last().unwrap(), cx) + ) + } else { + last.name.to_string() + } + } else { + anchor(did, last.name, cx).to_string() + }; + write!(w, "{}{}", path, last.args.print(cx))?; + } + Ok(()) +} + +fn primitive_link( + f: &mut fmt::Formatter<'_>, + prim: clean::PrimitiveType, + name: &str, + cx: &Context<'_>, +) -> fmt::Result { + primitive_link_fragment(f, prim, name, "", cx) +} + +fn primitive_link_fragment( + f: &mut fmt::Formatter<'_>, + prim: clean::PrimitiveType, + name: &str, + fragment: &str, + cx: &Context<'_>, +) -> fmt::Result { + let m = &cx.cache(); + let mut needs_termination = false; + if !f.alternate() { + match m.primitive_locations.get(&prim) { + Some(&def_id) if def_id.is_local() => { + let len = cx.current.len(); + let len = if len == 0 { 0 } else { len - 1 }; + write!( + f, + "", + "../".repeat(len), + prim.as_sym() + )?; + needs_termination = true; + } + Some(&def_id) => { + let loc = match m.extern_locations[&def_id.krate] { + ExternalLocation::Remote(ref s) => { + let cname_sym = ExternalCrate { crate_num: def_id.krate }.name(cx.tcx()); + let builder: UrlPartsBuilder = + [s.as_str().trim_end_matches('/'), cname_sym.as_str()] + .into_iter() + .collect(); + Some(builder) + } + ExternalLocation::Local => { + let cname_sym = ExternalCrate { crate_num: def_id.krate }.name(cx.tcx()); + Some(if cx.current.first() == Some(&cname_sym) { + iter::repeat(sym::dotdot).take(cx.current.len() - 1).collect() + } else { + iter::repeat(sym::dotdot) + .take(cx.current.len()) + .chain(iter::once(cname_sym)) + .collect() + }) + } + ExternalLocation::Unknown => None, + }; + if let Some(mut loc) = loc { + loc.push_fmt(format_args!("primitive.{}.html", prim.as_sym())); + write!(f, "", loc.finish())?; + needs_termination = true; + } + } + None => {} + } + } + write!(f, "{}", name)?; + if needs_termination { + write!(f, "")?; + } + Ok(()) +} + +/// Helper to render type parameters +fn tybounds<'a, 'tcx: 'a>( + bounds: &'a [clean::PolyTrait], + lt: &'a Option, + cx: &'a Context<'tcx>, +) -> impl fmt::Display + 'a + Captures<'tcx> { + display_fn(move |f| { + for (i, bound) in bounds.iter().enumerate() { + if i > 0 { + write!(f, " + ")?; + } + + fmt::Display::fmt(&bound.print(cx), f)?; + } + + if let Some(lt) = lt { + write!(f, " + ")?; + fmt::Display::fmt(<.print(), f)?; + } + Ok(()) + }) +} + +pub(crate) fn anchor<'a, 'cx: 'a>( + did: DefId, + text: Symbol, + cx: &'cx Context<'_>, +) -> impl fmt::Display + 'a { + let parts = href(did, cx); + display_fn(move |f| { + if let Ok((url, short_ty, fqp)) = parts { + write!( + f, + r#"{}"#, + short_ty, + url, + short_ty, + join_with_double_colon(&fqp), + text.as_str() + ) + } else { + write!(f, "{}", text) + } + }) +} + +fn fmt_type<'cx>( + t: &clean::Type, + f: &mut fmt::Formatter<'_>, + use_absolute: bool, + cx: &'cx Context<'_>, +) -> fmt::Result { + trace!("fmt_type(t = {:?})", t); + + match *t { + clean::Generic(name) => write!(f, "{}", name), + clean::Type::Path { ref path } => { + // Paths like `T::Output` and `Self::Output` should be rendered with all segments. + let did = path.def_id(); + resolved_path(f, did, path, path.is_assoc_ty(), use_absolute, cx) + } + clean::DynTrait(ref bounds, ref lt) => { + f.write_str("dyn ")?; + fmt::Display::fmt(&tybounds(bounds, lt, cx), f) + } + clean::Infer => write!(f, "_"), + clean::Primitive(clean::PrimitiveType::Never) => { + primitive_link(f, PrimitiveType::Never, "!", cx) + } + clean::Primitive(prim) => primitive_link(f, prim, prim.as_sym().as_str(), cx), + clean::BareFunction(ref decl) => { + if f.alternate() { + write!( + f, + "{:#}{}{:#}fn{:#}", + decl.print_hrtb_with_space(cx), + decl.unsafety.print_with_space(), + print_abi_with_space(decl.abi), + decl.decl.print(cx), + ) + } else { + write!( + f, + "{}{}{}", + decl.print_hrtb_with_space(cx), + decl.unsafety.print_with_space(), + print_abi_with_space(decl.abi) + )?; + primitive_link(f, PrimitiveType::Fn, "fn", cx)?; + write!(f, "{}", decl.decl.print(cx)) + } + } + clean::Tuple(ref typs) => { + match &typs[..] { + &[] => primitive_link(f, PrimitiveType::Unit, "()", cx), + &[ref one] => { + if let clean::Generic(name) = one { + primitive_link(f, PrimitiveType::Tuple, &format!("({name},)"), cx) + } else { + write!(f, "(")?; + // Carry `f.alternate()` into this display w/o branching manually. + fmt::Display::fmt(&one.print(cx), f)?; + write!(f, ",)") + } + } + many => { + let generic_names: Vec = many + .iter() + .filter_map(|t| match t { + clean::Generic(name) => Some(*name), + _ => None, + }) + .collect(); + let is_generic = generic_names.len() == many.len(); + if is_generic { + primitive_link( + f, + PrimitiveType::Tuple, + &format!("({})", generic_names.iter().map(|s| s.as_str()).join(", ")), + cx, + ) + } else { + write!(f, "(")?; + for (i, item) in many.iter().enumerate() { + if i != 0 { + write!(f, ", ")?; + } + // Carry `f.alternate()` into this display w/o branching manually. + fmt::Display::fmt(&item.print(cx), f)?; + } + write!(f, ")") + } + } + } + } + clean::Slice(ref t) => match **t { + clean::Generic(name) => { + primitive_link(f, PrimitiveType::Slice, &format!("[{name}]"), cx) + } + _ => { + write!(f, "[")?; + fmt::Display::fmt(&t.print(cx), f)?; + write!(f, "]") + } + }, + clean::Array(ref t, ref n) => { + primitive_link(f, PrimitiveType::Array, "[", cx)?; + fmt::Display::fmt(&t.print(cx), f)?; + if f.alternate() { + primitive_link(f, PrimitiveType::Array, &format!("; {}]", n), cx) + } else { + primitive_link(f, PrimitiveType::Array, &format!("; {}]", Escape(n)), cx) + } + } + clean::RawPointer(m, ref t) => { + let m = match m { + hir::Mutability::Mut => "mut", + hir::Mutability::Not => "const", + }; + + if matches!(**t, clean::Generic(_)) || t.is_assoc_ty() { + let text = if f.alternate() { + format!("*{} {:#}", m, t.print(cx)) + } else { + format!("*{} {}", m, t.print(cx)) + }; + primitive_link(f, clean::PrimitiveType::RawPointer, &text, cx) + } else { + primitive_link(f, clean::PrimitiveType::RawPointer, &format!("*{} ", m), cx)?; + fmt::Display::fmt(&t.print(cx), f) + } + } + clean::BorrowedRef { lifetime: ref l, mutability, type_: ref ty } => { + let lt = match l { + Some(l) => format!("{} ", l.print()), + _ => String::new(), + }; + let m = mutability.print_with_space(); + let amp = if f.alternate() { "&".to_string() } else { "&".to_string() }; + match **ty { + clean::DynTrait(ref bounds, ref trait_lt) + if bounds.len() > 1 || trait_lt.is_some() => + { + write!(f, "{}{}{}(", amp, lt, m)?; + fmt_type(ty, f, use_absolute, cx)?; + write!(f, ")") + } + clean::Generic(..) => { + primitive_link( + f, + PrimitiveType::Reference, + &format!("{}{}{}", amp, lt, m), + cx, + )?; + fmt_type(ty, f, use_absolute, cx) + } + _ => { + write!(f, "{}{}{}", amp, lt, m)?; + fmt_type(ty, f, use_absolute, cx) + } + } + } + clean::ImplTrait(ref bounds) => { + if f.alternate() { + write!(f, "impl {:#}", print_generic_bounds(bounds, cx)) + } else { + write!(f, "impl {}", print_generic_bounds(bounds, cx)) + } + } + clean::QPath { ref assoc, ref self_type, ref trait_, should_show_cast } => { + if f.alternate() { + if should_show_cast { + write!(f, "<{:#} as {:#}>::", self_type.print(cx), trait_.print(cx))? + } else { + write!(f, "{:#}::", self_type.print(cx))? + } + } else { + if should_show_cast { + write!(f, "<{} as {}>::", self_type.print(cx), trait_.print(cx))? + } else { + write!(f, "{}::", self_type.print(cx))? + } + }; + // It's pretty unsightly to look at `::C` in output, and + // we've got hyperlinking on our side, so try to avoid longer + // notation as much as possible by making `C` a hyperlink to trait + // `B` to disambiguate. + // + // FIXME: this is still a lossy conversion and there should probably + // be a better way of representing this in general? Most of + // the ugliness comes from inlining across crates where + // everything comes in as a fully resolved QPath (hard to + // look at). + match href(trait_.def_id(), cx) { + Ok((ref url, _, ref path)) if !f.alternate() => { + write!( + f, + "{name}{args}", + url = url, + shortty = ItemType::AssocType, + name = assoc.name, + path = join_with_double_colon(path), + args = assoc.args.print(cx), + )?; + } + _ => write!(f, "{}{:#}", assoc.name, assoc.args.print(cx))?, + } + Ok(()) + } + } +} + +impl clean::Type { + pub(crate) fn print<'b, 'a: 'b, 'tcx: 'a>( + &'a self, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'b + Captures<'tcx> { + display_fn(move |f| fmt_type(self, f, false, cx)) + } +} + +impl clean::Path { + pub(crate) fn print<'b, 'a: 'b, 'tcx: 'a>( + &'a self, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'b + Captures<'tcx> { + display_fn(move |f| resolved_path(f, self.def_id(), self, false, false, cx)) + } +} + +impl clean::Impl { + pub(crate) fn print<'a, 'tcx: 'a>( + &'a self, + use_absolute: bool, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'a + Captures<'tcx> { + display_fn(move |f| { + if f.alternate() { + write!(f, "impl{:#} ", self.generics.print(cx))?; + } else { + write!(f, "impl{} ", self.generics.print(cx))?; + } + + if let Some(ref ty) = self.trait_ { + match self.polarity { + ty::ImplPolarity::Positive | ty::ImplPolarity::Reservation => {} + ty::ImplPolarity::Negative => write!(f, "!")?, + } + fmt::Display::fmt(&ty.print(cx), f)?; + write!(f, " for ")?; + } + + if let clean::Type::Tuple(types) = &self.for_ && + let [clean::Type::Generic(name)] = &types[..] && + (self.kind.is_fake_variadic() || self.kind.is_auto()) + { + // Hardcoded anchor library/core/src/primitive_docs.rs + // Link should match `# Trait implementations` + primitive_link_fragment(f, PrimitiveType::Tuple, &format!("({name}₁, {name}₂, …, {name}ₙ)"), "#trait-implementations-1", cx)?; + } else if let clean::BareFunction(bare_fn) = &self.for_ && + let [clean::Argument { type_: clean::Type::Generic(name), .. }] = &bare_fn.decl.inputs.values[..] && + (self.kind.is_fake_variadic() || self.kind.is_auto()) + { + // Hardcoded anchor library/core/src/primitive_docs.rs + // Link should match `# Trait implementations` + + let hrtb = bare_fn.print_hrtb_with_space(cx); + let unsafety = bare_fn.unsafety.print_with_space(); + let abi = print_abi_with_space(bare_fn.abi); + if f.alternate() { + write!( + f, + "{hrtb:#}{unsafety}{abi:#}", + )?; + } else { + write!( + f, + "{hrtb}{unsafety}{abi}", + )?; + } + let ellipsis = if bare_fn.decl.c_variadic { + ", ..." + } else { + "" + }; + primitive_link_fragment(f, PrimitiveType::Tuple, &format!("fn ({name}₁, {name}₂, …, {name}ₙ{ellipsis})"), "#trait-implementations-1", cx)?; + // Write output. + if let clean::FnRetTy::Return(ty) = &bare_fn.decl.output { + write!(f, " -> ")?; + fmt_type(ty, f, use_absolute, cx)?; + } + } else if let Some(ty) = self.kind.as_blanket_ty() { + fmt_type(ty, f, use_absolute, cx)?; + } else { + fmt_type(&self.for_, f, use_absolute, cx)?; + } + + fmt::Display::fmt(&print_where_clause(&self.generics, cx, 0, Ending::Newline), f)?; + Ok(()) + }) + } +} + +impl clean::Arguments { + pub(crate) fn print<'a, 'tcx: 'a>( + &'a self, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'a + Captures<'tcx> { + display_fn(move |f| { + for (i, input) in self.values.iter().enumerate() { + if !input.name.is_empty() { + write!(f, "{}: ", input.name)?; + } + if f.alternate() { + write!(f, "{:#}", input.type_.print(cx))?; + } else { + write!(f, "{}", input.type_.print(cx))?; + } + if i + 1 < self.values.len() { + write!(f, ", ")?; + } + } + Ok(()) + }) + } +} + +impl clean::FnRetTy { + pub(crate) fn print<'a, 'tcx: 'a>( + &'a self, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'a + Captures<'tcx> { + display_fn(move |f| match self { + clean::Return(clean::Tuple(tys)) if tys.is_empty() => Ok(()), + clean::Return(ty) if f.alternate() => { + write!(f, " -> {:#}", ty.print(cx)) + } + clean::Return(ty) => write!(f, " -> {}", ty.print(cx)), + clean::DefaultReturn => Ok(()), + }) + } +} + +impl clean::BareFunctionDecl { + fn print_hrtb_with_space<'a, 'tcx: 'a>( + &'a self, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'a + Captures<'tcx> { + display_fn(move |f| { + if !self.generic_params.is_empty() { + write!( + f, + "for<{}> ", + comma_sep(self.generic_params.iter().map(|g| g.print(cx)), true) + ) + } else { + Ok(()) + } + }) + } +} + +impl clean::FnDecl { + pub(crate) fn print<'b, 'a: 'b, 'tcx: 'a>( + &'a self, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'b + Captures<'tcx> { + display_fn(move |f| { + let ellipsis = if self.c_variadic { ", ..." } else { "" }; + if f.alternate() { + write!( + f, + "({args:#}{ellipsis}){arrow:#}", + args = self.inputs.print(cx), + ellipsis = ellipsis, + arrow = self.output.print(cx) + ) + } else { + write!( + f, + "({args}{ellipsis}){arrow}", + args = self.inputs.print(cx), + ellipsis = ellipsis, + arrow = self.output.print(cx) + ) + } + }) + } + + /// * `header_len`: The length of the function header and name. In other words, the number of + /// characters in the function declaration up to but not including the parentheses. + ///
Used to determine line-wrapping. + /// * `indent`: The number of spaces to indent each successive line with, if line-wrapping is + /// necessary. + /// * `asyncness`: Whether the function is async or not. + pub(crate) fn full_print<'a, 'tcx: 'a>( + &'a self, + header_len: usize, + indent: usize, + asyncness: hir::IsAsync, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'a + Captures<'tcx> { + display_fn(move |f| self.inner_full_print(header_len, indent, asyncness, f, cx)) + } + + fn inner_full_print( + &self, + header_len: usize, + indent: usize, + asyncness: hir::IsAsync, + f: &mut fmt::Formatter<'_>, + cx: &Context<'_>, + ) -> fmt::Result { + let amp = if f.alternate() { "&" } else { "&" }; + let mut args = Buffer::html(); + let mut args_plain = Buffer::new(); + for (i, input) in self.inputs.values.iter().enumerate() { + if let Some(selfty) = input.to_self() { + match selfty { + clean::SelfValue => { + args.push_str("self"); + args_plain.push_str("self"); + } + clean::SelfBorrowed(Some(ref lt), mtbl) => { + write!(args, "{}{} {}self", amp, lt.print(), mtbl.print_with_space()); + write!(args_plain, "&{} {}self", lt.print(), mtbl.print_with_space()); + } + clean::SelfBorrowed(None, mtbl) => { + write!(args, "{}{}self", amp, mtbl.print_with_space()); + write!(args_plain, "&{}self", mtbl.print_with_space()); + } + clean::SelfExplicit(ref typ) => { + if f.alternate() { + write!(args, "self: {:#}", typ.print(cx)); + } else { + write!(args, "self: {}", typ.print(cx)); + } + write!(args_plain, "self: {:#}", typ.print(cx)); + } + } + } else { + if i > 0 { + args.push_str("
"); + } + if input.is_const { + args.push_str("const "); + args_plain.push_str("const "); + } + if !input.name.is_empty() { + write!(args, "{}: ", input.name); + write!(args_plain, "{}: ", input.name); + } + + if f.alternate() { + write!(args, "{:#}", input.type_.print(cx)); + } else { + write!(args, "{}", input.type_.print(cx)); + } + write!(args_plain, "{:#}", input.type_.print(cx)); + } + if i + 1 < self.inputs.values.len() { + args.push_str(","); + args_plain.push_str(","); + } + } + + let mut args_plain = format!("({})", args_plain.into_inner()); + let mut args = args.into_inner(); + + if self.c_variadic { + args.push_str(",
..."); + args_plain.push_str(", ..."); + } + + let arrow_plain; + let arrow = if let hir::IsAsync::Async = asyncness { + let output = self.sugared_async_return_type(); + arrow_plain = format!("{:#}", output.print(cx)); + if f.alternate() { arrow_plain.clone() } else { format!("{}", output.print(cx)) } + } else { + arrow_plain = format!("{:#}", self.output.print(cx)); + if f.alternate() { arrow_plain.clone() } else { format!("{}", self.output.print(cx)) } + }; + + let declaration_len = header_len + args_plain.len() + arrow_plain.len(); + let output = if declaration_len > 80 { + let full_pad = format!("
{}", " ".repeat(indent + 4)); + let close_pad = format!("
{}", " ".repeat(indent)); + format!( + "({pad}{args}{close}){arrow}", + pad = if self.inputs.values.is_empty() { "" } else { &full_pad }, + args = args.replace("
", &full_pad), + close = close_pad, + arrow = arrow + ) + } else { + format!("({args}){arrow}", args = args.replace("
", " "), arrow = arrow) + }; + + if f.alternate() { + write!(f, "{}", output.replace("
", "\n")) + } else { + write!(f, "{}", output) + } + } +} + +impl clean::Visibility { + pub(crate) fn print_with_space<'a, 'tcx: 'a>( + self, + item_did: ItemId, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'a + Captures<'tcx> { + use std::fmt::Write as _; + + let to_print: Cow<'static, str> = match self { + clean::Public => "pub ".into(), + clean::Inherited => "".into(), + clean::Visibility::Restricted(vis_did) => { + // FIXME(camelid): This may not work correctly if `item_did` is a module. + // However, rustdoc currently never displays a module's + // visibility, so it shouldn't matter. + let parent_module = find_nearest_parent_module(cx.tcx(), item_did.expect_def_id()); + + if vis_did.is_crate_root() { + "pub(crate) ".into() + } else if parent_module == Some(vis_did) { + // `pub(in foo)` where `foo` is the parent module + // is the same as no visibility modifier + "".into() + } else if parent_module + .and_then(|parent| find_nearest_parent_module(cx.tcx(), parent)) + == Some(vis_did) + { + "pub(super) ".into() + } else { + let path = cx.tcx().def_path(vis_did); + debug!("path={:?}", path); + // modified from `resolved_path()` to work with `DefPathData` + let last_name = path.data.last().unwrap().data.get_opt_name().unwrap(); + let anchor = anchor(vis_did, last_name, cx).to_string(); + + let mut s = "pub(in ".to_owned(); + for seg in &path.data[..path.data.len() - 1] { + let _ = write!(s, "{}::", seg.data.get_opt_name().unwrap()); + } + let _ = write!(s, "{}) ", anchor); + s.into() + } + } + }; + display_fn(move |f| write!(f, "{}", to_print)) + } + + /// This function is the same as print_with_space, except that it renders no links. + /// It's used for macros' rendered source view, which is syntax highlighted and cannot have + /// any HTML in it. + pub(crate) fn to_src_with_space<'a, 'tcx: 'a>( + self, + tcx: TyCtxt<'tcx>, + item_did: DefId, + ) -> impl fmt::Display + 'a + Captures<'tcx> { + let to_print = match self { + clean::Public => "pub ".to_owned(), + clean::Inherited => String::new(), + clean::Visibility::Restricted(vis_did) => { + // FIXME(camelid): This may not work correctly if `item_did` is a module. + // However, rustdoc currently never displays a module's + // visibility, so it shouldn't matter. + let parent_module = find_nearest_parent_module(tcx, item_did); + + if vis_did.is_crate_root() { + "pub(crate) ".to_owned() + } else if parent_module == Some(vis_did) { + // `pub(in foo)` where `foo` is the parent module + // is the same as no visibility modifier + String::new() + } else if parent_module.and_then(|parent| find_nearest_parent_module(tcx, parent)) + == Some(vis_did) + { + "pub(super) ".to_owned() + } else { + format!("pub(in {}) ", tcx.def_path_str(vis_did)) + } + } + }; + display_fn(move |f| f.write_str(&to_print)) + } +} + +pub(crate) trait PrintWithSpace { + fn print_with_space(&self) -> &str; +} + +impl PrintWithSpace for hir::Unsafety { + fn print_with_space(&self) -> &str { + match self { + hir::Unsafety::Unsafe => "unsafe ", + hir::Unsafety::Normal => "", + } + } +} + +impl PrintWithSpace for hir::IsAsync { + fn print_with_space(&self) -> &str { + match self { + hir::IsAsync::Async => "async ", + hir::IsAsync::NotAsync => "", + } + } +} + +impl PrintWithSpace for hir::Mutability { + fn print_with_space(&self) -> &str { + match self { + hir::Mutability::Not => "", + hir::Mutability::Mut => "mut ", + } + } +} + +pub(crate) fn print_constness_with_space( + c: &hir::Constness, + s: Option, +) -> &'static str { + match (c, s) { + // const stable or when feature(staged_api) is not set + ( + hir::Constness::Const, + Some(ConstStability { level: StabilityLevel::Stable { .. }, .. }), + ) + | (hir::Constness::Const, None) => "const ", + // const unstable or not const + _ => "", + } +} + +impl clean::Import { + pub(crate) fn print<'a, 'tcx: 'a>( + &'a self, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'a + Captures<'tcx> { + display_fn(move |f| match self.kind { + clean::ImportKind::Simple(name) => { + if name == self.source.path.last() { + write!(f, "use {};", self.source.print(cx)) + } else { + write!(f, "use {} as {};", self.source.print(cx), name) + } + } + clean::ImportKind::Glob => { + if self.source.path.segments.is_empty() { + write!(f, "use *;") + } else { + write!(f, "use {}::*;", self.source.print(cx)) + } + } + }) + } +} + +impl clean::ImportSource { + pub(crate) fn print<'a, 'tcx: 'a>( + &'a self, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'a + Captures<'tcx> { + display_fn(move |f| match self.did { + Some(did) => resolved_path(f, did, &self.path, true, false, cx), + _ => { + for seg in &self.path.segments[..self.path.segments.len() - 1] { + write!(f, "{}::", seg.name)?; + } + let name = self.path.last(); + if let hir::def::Res::PrimTy(p) = self.path.res { + primitive_link(f, PrimitiveType::from(p), name.as_str(), cx)?; + } else { + write!(f, "{}", name)?; + } + Ok(()) + } + }) + } +} + +impl clean::TypeBinding { + pub(crate) fn print<'a, 'tcx: 'a>( + &'a self, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'a + Captures<'tcx> { + display_fn(move |f| { + f.write_str(self.assoc.name.as_str())?; + if f.alternate() { + write!(f, "{:#}", self.assoc.args.print(cx))?; + } else { + write!(f, "{}", self.assoc.args.print(cx))?; + } + match self.kind { + clean::TypeBindingKind::Equality { ref term } => { + if f.alternate() { + write!(f, " = {:#}", term.print(cx))?; + } else { + write!(f, " = {}", term.print(cx))?; + } + } + clean::TypeBindingKind::Constraint { ref bounds } => { + if !bounds.is_empty() { + if f.alternate() { + write!(f, ": {:#}", print_generic_bounds(bounds, cx))?; + } else { + write!(f, ": {}", print_generic_bounds(bounds, cx))?; + } + } + } + } + Ok(()) + }) + } +} + +pub(crate) fn print_abi_with_space(abi: Abi) -> impl fmt::Display { + display_fn(move |f| { + let quot = if f.alternate() { "\"" } else { """ }; + match abi { + Abi::Rust => Ok(()), + abi => write!(f, "extern {0}{1}{0} ", quot, abi.name()), + } + }) +} + +pub(crate) fn print_default_space<'a>(v: bool) -> &'a str { + if v { "default " } else { "" } +} + +impl clean::GenericArg { + pub(crate) fn print<'a, 'tcx: 'a>( + &'a self, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'a + Captures<'tcx> { + display_fn(move |f| match self { + clean::GenericArg::Lifetime(lt) => fmt::Display::fmt(<.print(), f), + clean::GenericArg::Type(ty) => fmt::Display::fmt(&ty.print(cx), f), + clean::GenericArg::Const(ct) => fmt::Display::fmt(&ct.print(cx.tcx()), f), + clean::GenericArg::Infer => fmt::Display::fmt("_", f), + }) + } +} + +impl clean::types::Term { + pub(crate) fn print<'a, 'tcx: 'a>( + &'a self, + cx: &'a Context<'tcx>, + ) -> impl fmt::Display + 'a + Captures<'tcx> { + match self { + clean::types::Term::Type(ty) => ty.print(cx), + _ => todo!(), + } + } +} + +pub(crate) fn display_fn( + f: impl FnOnce(&mut fmt::Formatter<'_>) -> fmt::Result, +) -> impl fmt::Display { + struct WithFormatter(Cell>); + + impl fmt::Display for WithFormatter + where + F: FnOnce(&mut fmt::Formatter<'_>) -> fmt::Result, + { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + (self.0.take()).unwrap()(f) + } + } + + WithFormatter(Cell::new(Some(f))) +} diff --git a/src/librustdoc/html/highlight.rs b/src/librustdoc/html/highlight.rs new file mode 100644 index 000000000..05547ea15 --- /dev/null +++ b/src/librustdoc/html/highlight.rs @@ -0,0 +1,805 @@ +//! Basic syntax highlighting functionality. +//! +//! This module uses librustc_ast's lexer to provide token-based highlighting for +//! the HTML documentation generated by rustdoc. +//! +//! Use the `render_with_highlighting` to highlight some rust code. + +use crate::clean::PrimitiveType; +use crate::html::escape::Escape; +use crate::html::render::Context; + +use std::collections::VecDeque; +use std::fmt::{Display, Write}; + +use rustc_data_structures::fx::FxHashMap; +use rustc_lexer::{LiteralKind, TokenKind}; +use rustc_span::edition::Edition; +use rustc_span::symbol::Symbol; +use rustc_span::{BytePos, Span, DUMMY_SP}; + +use super::format::{self, Buffer}; +use super::render::LinkFromSrc; + +/// This type is needed in case we want to render links on items to allow to go to their definition. +pub(crate) struct HrefContext<'a, 'b, 'c> { + pub(crate) context: &'a Context<'b>, + /// This span contains the current file we're going through. + pub(crate) file_span: Span, + /// This field is used to know "how far" from the top of the directory we are to link to either + /// documentation pages or other source pages. + pub(crate) root_path: &'c str, +} + +/// Decorations are represented as a map from CSS class to vector of character ranges. +/// Each range will be wrapped in a span with that class. +pub(crate) struct DecorationInfo(pub(crate) FxHashMap<&'static str, Vec<(u32, u32)>>); + +/// Highlights `src`, returning the HTML output. +pub(crate) fn render_with_highlighting( + src: &str, + out: &mut Buffer, + class: Option<&str>, + playground_button: Option<&str>, + tooltip: Option<(Option, &str)>, + edition: Edition, + extra_content: Option, + href_context: Option>, + decoration_info: Option, +) { + debug!("highlighting: ================\n{}\n==============", src); + if let Some((edition_info, class)) = tooltip { + write!( + out, + "
ⓘ
", + class, + if let Some(edition_info) = edition_info { + format!(" data-edition=\"{}\"", edition_info) + } else { + String::new() + }, + ); + } + + write_header(out, class, extra_content); + write_code(out, src, edition, href_context, decoration_info); + write_footer(out, playground_button); +} + +fn write_header(out: &mut Buffer, class: Option<&str>, extra_content: Option) { + write!(out, "
"); + if let Some(extra) = extra_content { + out.push_buffer(extra); + } + if let Some(class) = class { + write!(out, "
", class);
+    } else {
+        write!(out, "
");
+    }
+    write!(out, "");
+}
+
+/// Convert the given `src` source code into HTML by adding classes for highlighting.
+///
+/// This code is used to render code blocks (in the documentation) as well as the source code pages.
+///
+/// Some explanations on the last arguments:
+///
+/// In case we are rendering a code block and not a source code file, `href_context` will be `None`.
+/// To put it more simply: if `href_context` is `None`, the code won't try to generate links to an
+/// item definition.
+///
+/// More explanations about spans and how we use them here are provided in the
+fn write_code(
+    out: &mut Buffer,
+    src: &str,
+    edition: Edition,
+    href_context: Option>,
+    decoration_info: Option,
+) {
+    // This replace allows to fix how the code source with DOS backline characters is displayed.
+    let src = src.replace("\r\n", "\n");
+    let mut closing_tags: Vec<&'static str> = Vec::new();
+    Classifier::new(
+        &src,
+        edition,
+        href_context.as_ref().map(|c| c.file_span).unwrap_or(DUMMY_SP),
+        decoration_info,
+    )
+    .highlight(&mut |highlight| {
+        match highlight {
+            Highlight::Token { text, class } => string(out, Escape(text), class, &href_context),
+            Highlight::EnterSpan { class } => {
+                closing_tags.push(enter_span(out, class, &href_context))
+            }
+            Highlight::ExitSpan => {
+                exit_span(out, closing_tags.pop().expect("ExitSpan without EnterSpan"))
+            }
+        };
+    });
+}
+
+fn write_footer(out: &mut Buffer, playground_button: Option<&str>) {
+    writeln!(out, "
{}
", playground_button.unwrap_or_default()); +} + +/// How a span of text is classified. Mostly corresponds to token kinds. +#[derive(Clone, Copy, Debug, Eq, PartialEq)] +enum Class { + Comment, + DocComment, + Attribute, + KeyWord, + // Keywords that do pointer/reference stuff. + RefKeyWord, + Self_(Span), + Op, + Macro(Span), + MacroNonTerminal, + String, + Number, + Bool, + Ident(Span), + Lifetime, + PreludeTy, + PreludeVal, + QuestionMark, + Decoration(&'static str), +} + +impl Class { + /// Returns the css class expected by rustdoc for each `Class`. + fn as_html(self) -> &'static str { + match self { + Class::Comment => "comment", + Class::DocComment => "doccomment", + Class::Attribute => "attribute", + Class::KeyWord => "kw", + Class::RefKeyWord => "kw-2", + Class::Self_(_) => "self", + Class::Op => "op", + Class::Macro(_) => "macro", + Class::MacroNonTerminal => "macro-nonterminal", + Class::String => "string", + Class::Number => "number", + Class::Bool => "bool-val", + Class::Ident(_) => "ident", + Class::Lifetime => "lifetime", + Class::PreludeTy => "prelude-ty", + Class::PreludeVal => "prelude-val", + Class::QuestionMark => "question-mark", + Class::Decoration(kind) => kind, + } + } + + /// In case this is an item which can be converted into a link to a definition, it'll contain + /// a "span" (a tuple representing `(lo, hi)` equivalent of `Span`). + fn get_span(self) -> Option { + match self { + Self::Ident(sp) | Self::Self_(sp) | Self::Macro(sp) => Some(sp), + Self::Comment + | Self::DocComment + | Self::Attribute + | Self::KeyWord + | Self::RefKeyWord + | Self::Op + | Self::MacroNonTerminal + | Self::String + | Self::Number + | Self::Bool + | Self::Lifetime + | Self::PreludeTy + | Self::PreludeVal + | Self::QuestionMark + | Self::Decoration(_) => None, + } + } +} + +enum Highlight<'a> { + Token { text: &'a str, class: Option }, + EnterSpan { class: Class }, + ExitSpan, +} + +struct TokenIter<'a> { + src: &'a str, +} + +impl<'a> Iterator for TokenIter<'a> { + type Item = (TokenKind, &'a str); + fn next(&mut self) -> Option<(TokenKind, &'a str)> { + if self.src.is_empty() { + return None; + } + let token = rustc_lexer::first_token(self.src); + let (text, rest) = self.src.split_at(token.len as usize); + self.src = rest; + Some((token.kind, text)) + } +} + +/// Classifies into identifier class; returns `None` if this is a non-keyword identifier. +fn get_real_ident_class(text: &str, edition: Edition, allow_path_keywords: bool) -> Option { + let ignore: &[&str] = + if allow_path_keywords { &["self", "Self", "super", "crate"] } else { &["self", "Self"] }; + if ignore.iter().any(|k| *k == text) { + return None; + } + Some(match text { + "ref" | "mut" => Class::RefKeyWord, + "false" | "true" => Class::Bool, + _ if Symbol::intern(text).is_reserved(|| edition) => Class::KeyWord, + _ => return None, + }) +} + +/// This iterator comes from the same idea than "Peekable" except that it allows to "peek" more than +/// just the next item by using `peek_next`. The `peek` method always returns the next item after +/// the current one whereas `peek_next` will return the next item after the last one peeked. +/// +/// You can use both `peek` and `peek_next` at the same time without problem. +struct PeekIter<'a> { + stored: VecDeque<(TokenKind, &'a str)>, + /// This position is reinitialized when using `next`. It is used in `peek_next`. + peek_pos: usize, + iter: TokenIter<'a>, +} + +impl<'a> PeekIter<'a> { + fn new(iter: TokenIter<'a>) -> Self { + Self { stored: VecDeque::new(), peek_pos: 0, iter } + } + /// Returns the next item after the current one. It doesn't interfer with `peek_next` output. + fn peek(&mut self) -> Option<&(TokenKind, &'a str)> { + if self.stored.is_empty() { + if let Some(next) = self.iter.next() { + self.stored.push_back(next); + } + } + self.stored.front() + } + /// Returns the next item after the last one peeked. It doesn't interfer with `peek` output. + fn peek_next(&mut self) -> Option<&(TokenKind, &'a str)> { + self.peek_pos += 1; + if self.peek_pos - 1 < self.stored.len() { + self.stored.get(self.peek_pos - 1) + } else if let Some(next) = self.iter.next() { + self.stored.push_back(next); + self.stored.back() + } else { + None + } + } +} + +impl<'a> Iterator for PeekIter<'a> { + type Item = (TokenKind, &'a str); + fn next(&mut self) -> Option { + self.peek_pos = 0; + if let Some(first) = self.stored.pop_front() { Some(first) } else { self.iter.next() } + } +} + +/// Custom spans inserted into the source. Eg --scrape-examples uses this to highlight function calls +struct Decorations { + starts: Vec<(u32, &'static str)>, + ends: Vec, +} + +impl Decorations { + fn new(info: DecorationInfo) -> Self { + // Extract tuples (start, end, kind) into separate sequences of (start, kind) and (end). + let (mut starts, mut ends): (Vec<_>, Vec<_>) = info + .0 + .into_iter() + .flat_map(|(kind, ranges)| ranges.into_iter().map(move |(lo, hi)| ((lo, kind), hi))) + .unzip(); + + // Sort the sequences in document order. + starts.sort_by_key(|(lo, _)| *lo); + ends.sort(); + + Decorations { starts, ends } + } +} + +/// Processes program tokens, classifying strings of text by highlighting +/// category (`Class`). +struct Classifier<'a> { + tokens: PeekIter<'a>, + in_attribute: bool, + in_macro: bool, + in_macro_nonterminal: bool, + edition: Edition, + byte_pos: u32, + file_span: Span, + src: &'a str, + decorations: Option, +} + +impl<'a> Classifier<'a> { + /// Takes as argument the source code to HTML-ify, the rust edition to use and the source code + /// file span which will be used later on by the `span_correspondance_map`. + fn new( + src: &str, + edition: Edition, + file_span: Span, + decoration_info: Option, + ) -> Classifier<'_> { + let tokens = PeekIter::new(TokenIter { src }); + let decorations = decoration_info.map(Decorations::new); + Classifier { + tokens, + in_attribute: false, + in_macro: false, + in_macro_nonterminal: false, + edition, + byte_pos: 0, + file_span, + src, + decorations, + } + } + + /// Convenient wrapper to create a [`Span`] from a position in the file. + fn new_span(&self, lo: u32, text: &str) -> Span { + let hi = lo + text.len() as u32; + let file_lo = self.file_span.lo(); + self.file_span.with_lo(file_lo + BytePos(lo)).with_hi(file_lo + BytePos(hi)) + } + + /// Concatenate colons and idents as one when possible. + fn get_full_ident_path(&mut self) -> Vec<(TokenKind, usize, usize)> { + let start = self.byte_pos as usize; + let mut pos = start; + let mut has_ident = false; + let edition = self.edition; + + loop { + let mut nb = 0; + while let Some((TokenKind::Colon, _)) = self.tokens.peek() { + self.tokens.next(); + nb += 1; + } + // Ident path can start with "::" but if we already have content in the ident path, + // the "::" is mandatory. + if has_ident && nb == 0 { + return vec![(TokenKind::Ident, start, pos)]; + } else if nb != 0 && nb != 2 { + if has_ident { + return vec![(TokenKind::Ident, start, pos), (TokenKind::Colon, pos, pos + nb)]; + } else { + return vec![(TokenKind::Colon, start, pos + nb)]; + } + } + + if let Some((None, text)) = self.tokens.peek().map(|(token, text)| { + if *token == TokenKind::Ident { + let class = get_real_ident_class(text, edition, true); + (class, text) + } else { + // Doesn't matter which Class we put in here... + (Some(Class::Comment), text) + } + }) { + // We only "add" the colon if there is an ident behind. + pos += text.len() + nb; + has_ident = true; + self.tokens.next(); + } else if nb > 0 && has_ident { + return vec![(TokenKind::Ident, start, pos), (TokenKind::Colon, pos, pos + nb)]; + } else if nb > 0 { + return vec![(TokenKind::Colon, start, start + nb)]; + } else if has_ident { + return vec![(TokenKind::Ident, start, pos)]; + } else { + return Vec::new(); + } + } + } + + /// Wraps the tokens iteration to ensure that the `byte_pos` is always correct. + /// + /// It returns the token's kind, the token as a string and its byte position in the source + /// string. + fn next(&mut self) -> Option<(TokenKind, &'a str, u32)> { + if let Some((kind, text)) = self.tokens.next() { + let before = self.byte_pos; + self.byte_pos += text.len() as u32; + Some((kind, text, before)) + } else { + None + } + } + + /// Exhausts the `Classifier` writing the output into `sink`. + /// + /// The general structure for this method is to iterate over each token, + /// possibly giving it an HTML span with a class specifying what flavor of + /// token is used. + fn highlight(mut self, sink: &mut dyn FnMut(Highlight<'a>)) { + loop { + if let Some(decs) = self.decorations.as_mut() { + let byte_pos = self.byte_pos; + let n_starts = decs.starts.iter().filter(|(i, _)| byte_pos >= *i).count(); + for (_, kind) in decs.starts.drain(0..n_starts) { + sink(Highlight::EnterSpan { class: Class::Decoration(kind) }); + } + + let n_ends = decs.ends.iter().filter(|i| byte_pos >= **i).count(); + for _ in decs.ends.drain(0..n_ends) { + sink(Highlight::ExitSpan); + } + } + + if self + .tokens + .peek() + .map(|t| matches!(t.0, TokenKind::Colon | TokenKind::Ident)) + .unwrap_or(false) + { + let tokens = self.get_full_ident_path(); + for (token, start, end) in &tokens { + let text = &self.src[*start..*end]; + self.advance(*token, text, sink, *start as u32); + self.byte_pos += text.len() as u32; + } + if !tokens.is_empty() { + continue; + } + } + if let Some((token, text, before)) = self.next() { + self.advance(token, text, sink, before); + } else { + break; + } + } + } + + /// Single step of highlighting. This will classify `token`, but maybe also a couple of + /// following ones as well. + /// + /// `before` is the position of the given token in the `source` string and is used as "lo" byte + /// in case we want to try to generate a link for this token using the + /// `span_correspondance_map`. + fn advance( + &mut self, + token: TokenKind, + text: &'a str, + sink: &mut dyn FnMut(Highlight<'a>), + before: u32, + ) { + let lookahead = self.peek(); + let no_highlight = |sink: &mut dyn FnMut(_)| sink(Highlight::Token { text, class: None }); + let class = match token { + TokenKind::Whitespace => return no_highlight(sink), + TokenKind::LineComment { doc_style } | TokenKind::BlockComment { doc_style, .. } => { + if doc_style.is_some() { + Class::DocComment + } else { + Class::Comment + } + } + // Consider this as part of a macro invocation if there was a + // leading identifier. + TokenKind::Bang if self.in_macro => { + self.in_macro = false; + sink(Highlight::Token { text, class: None }); + sink(Highlight::ExitSpan); + return; + } + + // Assume that '&' or '*' is the reference or dereference operator + // or a reference or pointer type. Unless, of course, it looks like + // a logical and or a multiplication operator: `&&` or `* `. + TokenKind::Star => match self.tokens.peek() { + Some((TokenKind::Whitespace, _)) => Class::Op, + Some((TokenKind::Ident, "mut")) => { + self.next(); + sink(Highlight::Token { text: "*mut", class: Some(Class::RefKeyWord) }); + return; + } + Some((TokenKind::Ident, "const")) => { + self.next(); + sink(Highlight::Token { text: "*const", class: Some(Class::RefKeyWord) }); + return; + } + _ => Class::RefKeyWord, + }, + TokenKind::And => match self.tokens.peek() { + Some((TokenKind::And, _)) => { + self.next(); + sink(Highlight::Token { text: "&&", class: Some(Class::Op) }); + return; + } + Some((TokenKind::Eq, _)) => { + self.next(); + sink(Highlight::Token { text: "&=", class: Some(Class::Op) }); + return; + } + Some((TokenKind::Whitespace, _)) => Class::Op, + Some((TokenKind::Ident, "mut")) => { + self.next(); + sink(Highlight::Token { text: "&mut", class: Some(Class::RefKeyWord) }); + return; + } + _ => Class::RefKeyWord, + }, + + // These can either be operators, or arrows. + TokenKind::Eq => match lookahead { + Some(TokenKind::Eq) => { + self.next(); + sink(Highlight::Token { text: "==", class: Some(Class::Op) }); + return; + } + Some(TokenKind::Gt) => { + self.next(); + sink(Highlight::Token { text: "=>", class: None }); + return; + } + _ => Class::Op, + }, + TokenKind::Minus if lookahead == Some(TokenKind::Gt) => { + self.next(); + sink(Highlight::Token { text: "->", class: None }); + return; + } + + // Other operators. + TokenKind::Minus + | TokenKind::Plus + | TokenKind::Or + | TokenKind::Slash + | TokenKind::Caret + | TokenKind::Percent + | TokenKind::Bang + | TokenKind::Lt + | TokenKind::Gt => Class::Op, + + // Miscellaneous, no highlighting. + TokenKind::Dot + | TokenKind::Semi + | TokenKind::Comma + | TokenKind::OpenParen + | TokenKind::CloseParen + | TokenKind::OpenBrace + | TokenKind::CloseBrace + | TokenKind::OpenBracket + | TokenKind::At + | TokenKind::Tilde + | TokenKind::Colon + | TokenKind::Unknown => return no_highlight(sink), + + TokenKind::Question => Class::QuestionMark, + + TokenKind::Dollar => match lookahead { + Some(TokenKind::Ident) => { + self.in_macro_nonterminal = true; + Class::MacroNonTerminal + } + _ => return no_highlight(sink), + }, + + // This might be the start of an attribute. We're going to want to + // continue highlighting it as an attribute until the ending ']' is + // seen, so skip out early. Down below we terminate the attribute + // span when we see the ']'. + TokenKind::Pound => { + match lookahead { + // Case 1: #![inner_attribute] + Some(TokenKind::Bang) => { + self.next(); + if let Some(TokenKind::OpenBracket) = self.peek() { + self.in_attribute = true; + sink(Highlight::EnterSpan { class: Class::Attribute }); + } + sink(Highlight::Token { text: "#", class: None }); + sink(Highlight::Token { text: "!", class: None }); + return; + } + // Case 2: #[outer_attribute] + Some(TokenKind::OpenBracket) => { + self.in_attribute = true; + sink(Highlight::EnterSpan { class: Class::Attribute }); + } + _ => (), + } + return no_highlight(sink); + } + TokenKind::CloseBracket => { + if self.in_attribute { + self.in_attribute = false; + sink(Highlight::Token { text: "]", class: None }); + sink(Highlight::ExitSpan); + return; + } + return no_highlight(sink); + } + TokenKind::Literal { kind, .. } => match kind { + // Text literals. + LiteralKind::Byte { .. } + | LiteralKind::Char { .. } + | LiteralKind::Str { .. } + | LiteralKind::ByteStr { .. } + | LiteralKind::RawStr { .. } + | LiteralKind::RawByteStr { .. } => Class::String, + // Number literals. + LiteralKind::Float { .. } | LiteralKind::Int { .. } => Class::Number, + }, + TokenKind::Ident | TokenKind::RawIdent if lookahead == Some(TokenKind::Bang) => { + self.in_macro = true; + sink(Highlight::EnterSpan { class: Class::Macro(self.new_span(before, text)) }); + sink(Highlight::Token { text, class: None }); + return; + } + TokenKind::Ident => match get_real_ident_class(text, self.edition, false) { + None => match text { + "Option" | "Result" => Class::PreludeTy, + "Some" | "None" | "Ok" | "Err" => Class::PreludeVal, + // "union" is a weak keyword and is only considered as a keyword when declaring + // a union type. + "union" if self.check_if_is_union_keyword() => Class::KeyWord, + _ if self.in_macro_nonterminal => { + self.in_macro_nonterminal = false; + Class::MacroNonTerminal + } + "self" | "Self" => Class::Self_(self.new_span(before, text)), + _ => Class::Ident(self.new_span(before, text)), + }, + Some(c) => c, + }, + TokenKind::RawIdent | TokenKind::UnknownPrefix | TokenKind::InvalidIdent => { + Class::Ident(self.new_span(before, text)) + } + TokenKind::Lifetime { .. } => Class::Lifetime, + }; + // Anything that didn't return above is the simple case where we the + // class just spans a single token, so we can use the `string` method. + sink(Highlight::Token { text, class: Some(class) }); + } + + fn peek(&mut self) -> Option { + self.tokens.peek().map(|(token_kind, _text)| *token_kind) + } + + fn check_if_is_union_keyword(&mut self) -> bool { + while let Some(kind) = self.tokens.peek_next().map(|(token_kind, _text)| token_kind) { + if *kind == TokenKind::Whitespace { + continue; + } + return *kind == TokenKind::Ident; + } + false + } +} + +/// Called when we start processing a span of text that should be highlighted. +/// The `Class` argument specifies how it should be highlighted. +fn enter_span( + out: &mut Buffer, + klass: Class, + href_context: &Option>, +) -> &'static str { + string_without_closing_tag(out, "", Some(klass), href_context).expect( + "internal error: enter_span was called with Some(klass) but did not return a \ + closing HTML tag", + ) +} + +/// Called at the end of a span of highlighted text. +fn exit_span(out: &mut Buffer, closing_tag: &str) { + out.write_str(closing_tag); +} + +/// Called for a span of text. If the text should be highlighted differently +/// from the surrounding text, then the `Class` argument will be a value other +/// than `None`. +/// +/// The following sequences of callbacks are equivalent: +/// ```plain +/// enter_span(Foo), string("text", None), exit_span() +/// string("text", Foo) +/// ``` +/// +/// The latter can be thought of as a shorthand for the former, which is more +/// flexible. +/// +/// Note that if `context` is not `None` and that the given `klass` contains a `Span`, the function +/// will then try to find this `span` in the `span_correspondance_map`. If found, it'll then +/// generate a link for this element (which corresponds to where its definition is located). +fn string( + out: &mut Buffer, + text: T, + klass: Option, + href_context: &Option>, +) { + if let Some(closing_tag) = string_without_closing_tag(out, text, klass, href_context) { + out.write_str(closing_tag); + } +} + +/// This function writes `text` into `out` with some modifications depending on `klass`: +/// +/// * If `klass` is `None`, `text` is written into `out` with no modification. +/// * If `klass` is `Some` but `klass.get_span()` is `None`, it writes the text wrapped in a +/// `` with the provided `klass`. +/// * If `klass` is `Some` and has a [`rustc_span::Span`], it then tries to generate a link (`` +/// element) by retrieving the link information from the `span_correspondance_map` that was filled +/// in `span_map.rs::collect_spans_and_sources`. If it cannot retrieve the information, then it's +/// the same as the second point (`klass` is `Some` but doesn't have a [`rustc_span::Span`]). +fn string_without_closing_tag( + out: &mut Buffer, + text: T, + klass: Option, + href_context: &Option>, +) -> Option<&'static str> { + let Some(klass) = klass + else { + write!(out, "{}", text); + return None; + }; + let Some(def_span) = klass.get_span() + else { + write!(out, "{}", klass.as_html(), text); + return Some(""); + }; + + let mut text_s = text.to_string(); + if text_s.contains("::") { + text_s = text_s.split("::").intersperse("::").fold(String::new(), |mut path, t| { + match t { + "self" | "Self" => write!( + &mut path, + "{}", + Class::Self_(DUMMY_SP).as_html(), + t + ), + "crate" | "super" => { + write!(&mut path, "{}", Class::KeyWord.as_html(), t) + } + t => write!(&mut path, "{}", t), + } + .expect("Failed to build source HTML path"); + path + }); + } + if let Some(href_context) = href_context { + if let Some(href) = + href_context.context.shared.span_correspondance_map.get(&def_span).and_then(|href| { + let context = href_context.context; + // FIXME: later on, it'd be nice to provide two links (if possible) for all items: + // one to the documentation page and one to the source definition. + // FIXME: currently, external items only generate a link to their documentation, + // a link to their definition can be generated using this: + // https://github.com/rust-lang/rust/blob/60f1a2fc4b535ead9c85ce085fdce49b1b097531/src/librustdoc/html/render/context.rs#L315-L338 + match href { + LinkFromSrc::Local(span) => context + .href_from_span(*span, true) + .map(|s| format!("{}{}", href_context.root_path, s)), + LinkFromSrc::External(def_id) => { + format::href_with_root_path(*def_id, context, Some(href_context.root_path)) + .ok() + .map(|(url, _, _)| url) + } + LinkFromSrc::Primitive(prim) => format::href_with_root_path( + PrimitiveType::primitive_locations(context.tcx())[prim], + context, + Some(href_context.root_path), + ) + .ok() + .map(|(url, _, _)| url), + } + }) + { + write!(out, "{}", klass.as_html(), href, text_s); + return Some(""); + } + } + write!(out, "{}", klass.as_html(), text_s); + Some("") +} + +#[cfg(test)] +mod tests; diff --git a/src/librustdoc/html/highlight/fixtures/decorations.html b/src/librustdoc/html/highlight/fixtures/decorations.html new file mode 100644 index 000000000..45f567880 --- /dev/null +++ b/src/librustdoc/html/highlight/fixtures/decorations.html @@ -0,0 +1,2 @@ +let x = 1; +let y = 2; \ No newline at end of file diff --git a/src/librustdoc/html/highlight/fixtures/dos_line.html b/src/librustdoc/html/highlight/fixtures/dos_line.html new file mode 100644 index 000000000..1c8dbffe7 --- /dev/null +++ b/src/librustdoc/html/highlight/fixtures/dos_line.html @@ -0,0 +1,3 @@ +pub fn foo() { +println!("foo"); +} diff --git a/src/librustdoc/html/highlight/fixtures/highlight.html b/src/librustdoc/html/highlight/fixtures/highlight.html new file mode 100644 index 000000000..abc2db179 --- /dev/null +++ b/src/librustdoc/html/highlight/fixtures/highlight.html @@ -0,0 +1,4 @@ +use crate::a::foo; +use self::whatever; +let x = super::b::foo; +let y = Self::whatever; \ No newline at end of file diff --git a/src/librustdoc/html/highlight/fixtures/sample.html b/src/librustdoc/html/highlight/fixtures/sample.html new file mode 100644 index 000000000..b117a12e3 --- /dev/null +++ b/src/librustdoc/html/highlight/fixtures/sample.html @@ -0,0 +1,37 @@ + + +
#![crate_type = "lib"]
+
+use std::path::{Path, PathBuf};
+
+#[cfg(target_os = "linux")]
+fn main() -> () {
+    let foo = true && false || true;
+    let _: *const () = 0;
+    let _ = &foo;
+    let _ = &&foo;
+    let _ = *foo;
+    mac!(foo, &mut bar);
+    assert!(self.length < N && index <= self.length);
+    ::std::env::var("gateau").is_ok();
+    #[rustfmt::skip]
+    let s:std::path::PathBuf = std::path::PathBuf::new();
+    let mut s = String::new();
+
+    match &s {
+        ref mut x => {}
+    }
+}
+
+macro_rules! bar {
+    ($foo:tt) => {};
+}
+
diff --git a/src/librustdoc/html/highlight/fixtures/sample.rs b/src/librustdoc/html/highlight/fixtures/sample.rs new file mode 100644 index 000000000..fbfdc6767 --- /dev/null +++ b/src/librustdoc/html/highlight/fixtures/sample.rs @@ -0,0 +1,26 @@ +#![crate_type = "lib"] + +use std::path::{Path, PathBuf}; + +#[cfg(target_os = "linux")] +fn main() -> () { + let foo = true && false || true; + let _: *const () = 0; + let _ = &foo; + let _ = &&foo; + let _ = *foo; + mac!(foo, &mut bar); + assert!(self.length < N && index <= self.length); + ::std::env::var("gateau").is_ok(); + #[rustfmt::skip] + let s:std::path::PathBuf = std::path::PathBuf::new(); + let mut s = String::new(); + + match &s { + ref mut x => {} + } +} + +macro_rules! bar { + ($foo:tt) => {}; +} diff --git a/src/librustdoc/html/highlight/fixtures/union.html b/src/librustdoc/html/highlight/fixtures/union.html new file mode 100644 index 000000000..c0acf31a0 --- /dev/null +++ b/src/librustdoc/html/highlight/fixtures/union.html @@ -0,0 +1,8 @@ +union Foo { + i: i8, + u: i8, +} + +fn main() { + let union = 0; +} diff --git a/src/librustdoc/html/highlight/fixtures/union.rs b/src/librustdoc/html/highlight/fixtures/union.rs new file mode 100644 index 000000000..269ee115d --- /dev/null +++ b/src/librustdoc/html/highlight/fixtures/union.rs @@ -0,0 +1,8 @@ +union Foo { + i: i8, + u: i8, +} + +fn main() { + let union = 0; +} diff --git a/src/librustdoc/html/highlight/tests.rs b/src/librustdoc/html/highlight/tests.rs new file mode 100644 index 000000000..1fea7e983 --- /dev/null +++ b/src/librustdoc/html/highlight/tests.rs @@ -0,0 +1,81 @@ +use super::{write_code, DecorationInfo}; +use crate::html::format::Buffer; +use expect_test::expect_file; +use rustc_data_structures::fx::FxHashMap; +use rustc_span::create_default_session_globals_then; +use rustc_span::edition::Edition; + +const STYLE: &str = r#" + +"#; + +#[test] +fn test_html_highlighting() { + create_default_session_globals_then(|| { + let src = include_str!("fixtures/sample.rs"); + let html = { + let mut out = Buffer::new(); + write_code(&mut out, src, Edition::Edition2018, None, None); + format!("{}
{}
\n", STYLE, out.into_inner()) + }; + expect_file!["fixtures/sample.html"].assert_eq(&html); + }); +} + +#[test] +fn test_dos_backline() { + create_default_session_globals_then(|| { + let src = "pub fn foo() {\r\n\ + println!(\"foo\");\r\n\ +}\r\n"; + let mut html = Buffer::new(); + write_code(&mut html, src, Edition::Edition2018, None, None); + expect_file!["fixtures/dos_line.html"].assert_eq(&html.into_inner()); + }); +} + +#[test] +fn test_keyword_highlight() { + create_default_session_globals_then(|| { + let src = "use crate::a::foo; +use self::whatever; +let x = super::b::foo; +let y = Self::whatever;"; + + let mut html = Buffer::new(); + write_code(&mut html, src, Edition::Edition2018, None, None); + expect_file!["fixtures/highlight.html"].assert_eq(&html.into_inner()); + }); +} + +#[test] +fn test_union_highlighting() { + create_default_session_globals_then(|| { + let src = include_str!("fixtures/union.rs"); + let mut html = Buffer::new(); + write_code(&mut html, src, Edition::Edition2018, None, None); + expect_file!["fixtures/union.html"].assert_eq(&html.into_inner()); + }); +} + +#[test] +fn test_decorations() { + create_default_session_globals_then(|| { + let src = "let x = 1; +let y = 2;"; + let mut decorations = FxHashMap::default(); + decorations.insert("example", vec![(0, 10)]); + + let mut html = Buffer::new(); + write_code(&mut html, src, Edition::Edition2018, None, Some(DecorationInfo(decorations))); + expect_file!["fixtures/decorations.html"].assert_eq(&html.into_inner()); + }); +} diff --git a/src/librustdoc/html/layout.rs b/src/librustdoc/html/layout.rs new file mode 100644 index 000000000..7d6d4b71e --- /dev/null +++ b/src/librustdoc/html/layout.rs @@ -0,0 +1,103 @@ +use std::path::PathBuf; + +use rustc_data_structures::fx::FxHashMap; + +use crate::error::Error; +use crate::externalfiles::ExternalHtml; +use crate::html::format::{Buffer, Print}; +use crate::html::render::{ensure_trailing_slash, StylePath}; + +use askama::Template; + +#[derive(Clone)] +pub(crate) struct Layout { + pub(crate) logo: String, + pub(crate) favicon: String, + pub(crate) external_html: ExternalHtml, + pub(crate) default_settings: FxHashMap, + pub(crate) krate: String, + /// The given user css file which allow to customize the generated + /// documentation theme. + pub(crate) css_file_extension: Option, + /// If true, then scrape-examples.js will be included in the output HTML file + pub(crate) scrape_examples_extension: bool, +} + +pub(crate) struct Page<'a> { + pub(crate) title: &'a str, + pub(crate) css_class: &'a str, + pub(crate) root_path: &'a str, + pub(crate) static_root_path: Option<&'a str>, + pub(crate) description: &'a str, + pub(crate) keywords: &'a str, + pub(crate) resource_suffix: &'a str, +} + +impl<'a> Page<'a> { + pub(crate) fn get_static_root_path(&self) -> &str { + self.static_root_path.unwrap_or(self.root_path) + } +} + +#[derive(Template)] +#[template(path = "page.html")] +struct PageLayout<'a> { + static_root_path: &'a str, + page: &'a Page<'a>, + layout: &'a Layout, + themes: Vec, + sidebar: String, + content: String, + krate_with_trailing_slash: String, + pub(crate) rustdoc_version: &'a str, +} + +pub(crate) fn render( + layout: &Layout, + page: &Page<'_>, + sidebar: S, + t: T, + style_files: &[StylePath], +) -> String { + let static_root_path = page.get_static_root_path(); + let krate_with_trailing_slash = ensure_trailing_slash(&layout.krate).to_string(); + let mut themes: Vec = style_files + .iter() + .map(StylePath::basename) + .collect::>() + .unwrap_or_default(); + themes.sort(); + let rustdoc_version = rustc_interface::util::version_str().unwrap_or("unknown version"); + let content = Buffer::html().to_display(t); // Note: This must happen before making the sidebar. + let sidebar = Buffer::html().to_display(sidebar); + PageLayout { + static_root_path, + page, + layout, + themes, + sidebar, + content, + krate_with_trailing_slash, + rustdoc_version, + } + .render() + .unwrap() +} + +pub(crate) fn redirect(url: &str) -> String { + // + +"##, + url = url, + ) +} diff --git a/src/librustdoc/html/length_limit.rs b/src/librustdoc/html/length_limit.rs new file mode 100644 index 000000000..bbdc91c8d --- /dev/null +++ b/src/librustdoc/html/length_limit.rs @@ -0,0 +1,119 @@ +//! See [`HtmlWithLimit`]. + +use std::fmt::Write; +use std::ops::ControlFlow; + +use crate::html::escape::Escape; + +/// A buffer that allows generating HTML with a length limit. +/// +/// This buffer ensures that: +/// +/// * all tags are closed, +/// * tags are closed in the reverse order of when they were opened (i.e., the correct HTML order), +/// * no tags are left empty (e.g., ``) due to the length limit being reached, +/// * all text is escaped. +#[derive(Debug)] +pub(super) struct HtmlWithLimit { + buf: String, + len: usize, + limit: usize, + /// A list of tags that have been requested to be opened via [`Self::open_tag()`] + /// but have not actually been pushed to `buf` yet. This ensures that tags are not + /// left empty (e.g., ``) due to the length limit being reached. + queued_tags: Vec<&'static str>, + /// A list of all tags that have been opened but not yet closed. + unclosed_tags: Vec<&'static str>, +} + +impl HtmlWithLimit { + /// Create a new buffer, with a limit of `length_limit`. + pub(super) fn new(length_limit: usize) -> Self { + let buf = if length_limit > 1000 { + // If the length limit is really large, don't preallocate tons of memory. + String::new() + } else { + // The length limit is actually a good heuristic for initial allocation size. + // Measurements showed that using it as the initial capacity ended up using less memory + // than `String::new`. + // See https://github.com/rust-lang/rust/pull/88173#discussion_r692531631 for more. + String::with_capacity(length_limit) + }; + Self { + buf, + len: 0, + limit: length_limit, + unclosed_tags: Vec::new(), + queued_tags: Vec::new(), + } + } + + /// Finish using the buffer and get the written output. + /// This function will close all unclosed tags for you. + pub(super) fn finish(mut self) -> String { + self.close_all_tags(); + self.buf + } + + /// Write some plain text to the buffer, escaping as needed. + /// + /// This function skips writing the text if the length limit was reached + /// and returns [`ControlFlow::Break`]. + pub(super) fn push(&mut self, text: &str) -> ControlFlow<(), ()> { + if self.len + text.len() > self.limit { + return ControlFlow::BREAK; + } + + self.flush_queue(); + write!(self.buf, "{}", Escape(text)).unwrap(); + self.len += text.len(); + + ControlFlow::CONTINUE + } + + /// Open an HTML tag. + /// + /// **Note:** HTML attributes have not yet been implemented. + /// This function will panic if called with a non-alphabetic `tag_name`. + pub(super) fn open_tag(&mut self, tag_name: &'static str) { + assert!( + tag_name.chars().all(|c| ('a'..='z').contains(&c)), + "tag_name contained non-alphabetic chars: {:?}", + tag_name + ); + self.queued_tags.push(tag_name); + } + + /// Close the most recently opened HTML tag. + pub(super) fn close_tag(&mut self) { + match self.unclosed_tags.pop() { + // Close the most recently opened tag. + Some(tag_name) => write!(self.buf, "", tag_name).unwrap(), + // There are valid cases where `close_tag()` is called without + // there being any tags to close. For example, this occurs when + // a tag is opened after the length limit is exceeded; + // `flush_queue()` will never be called, and thus, the tag will + // not end up being added to `unclosed_tags`. + None => {} + } + } + + /// Write all queued tags and add them to the `unclosed_tags` list. + fn flush_queue(&mut self) { + for tag_name in self.queued_tags.drain(..) { + write!(self.buf, "<{}>", tag_name).unwrap(); + + self.unclosed_tags.push(tag_name); + } + } + + /// Close all unclosed tags. + fn close_all_tags(&mut self) { + while !self.unclosed_tags.is_empty() { + self.close_tag(); + } + } +} + +#[cfg(test)] +mod tests; diff --git a/src/librustdoc/html/length_limit/tests.rs b/src/librustdoc/html/length_limit/tests.rs new file mode 100644 index 000000000..2d02b8a16 --- /dev/null +++ b/src/librustdoc/html/length_limit/tests.rs @@ -0,0 +1,120 @@ +use super::*; + +#[test] +fn empty() { + assert_eq!(HtmlWithLimit::new(0).finish(), ""); + assert_eq!(HtmlWithLimit::new(60).finish(), ""); +} + +#[test] +fn basic() { + let mut buf = HtmlWithLimit::new(60); + buf.push("Hello "); + buf.open_tag("em"); + buf.push("world"); + buf.close_tag(); + buf.push("!"); + assert_eq!(buf.finish(), "Hello world!"); +} + +#[test] +fn no_tags() { + let mut buf = HtmlWithLimit::new(60); + buf.push("Hello"); + buf.push(" world!"); + assert_eq!(buf.finish(), "Hello world!"); +} + +#[test] +fn limit_0() { + let mut buf = HtmlWithLimit::new(0); + buf.push("Hello "); + buf.open_tag("em"); + buf.push("world"); + buf.close_tag(); + buf.push("!"); + assert_eq!(buf.finish(), ""); +} + +#[test] +fn exactly_limit() { + let mut buf = HtmlWithLimit::new(12); + buf.push("Hello "); + buf.open_tag("em"); + buf.push("world"); + buf.close_tag(); + buf.push("!"); + assert_eq!(buf.finish(), "Hello world!"); +} + +#[test] +fn multiple_nested_tags() { + let mut buf = HtmlWithLimit::new(60); + buf.open_tag("p"); + buf.push("This is a "); + buf.open_tag("em"); + buf.push("paragraph"); + buf.open_tag("strong"); + buf.push("!"); + buf.close_tag(); + buf.close_tag(); + buf.close_tag(); + assert_eq!(buf.finish(), "

This is a paragraph!

"); +} + +#[test] +fn forgot_to_close_tags() { + let mut buf = HtmlWithLimit::new(60); + buf.open_tag("p"); + buf.push("This is a "); + buf.open_tag("em"); + buf.push("paragraph"); + buf.open_tag("strong"); + buf.push("!"); + assert_eq!(buf.finish(), "

This is a paragraph!

"); +} + +#[test] +fn past_the_limit() { + let mut buf = HtmlWithLimit::new(20); + buf.open_tag("p"); + (0..10).try_for_each(|n| { + buf.open_tag("strong"); + buf.push("word#")?; + buf.push(&n.to_string())?; + buf.close_tag(); + ControlFlow::CONTINUE + }); + buf.close_tag(); + assert_eq!( + buf.finish(), + "

\ + word#0\ + word#1\ + word#2\ +

" + ); +} + +#[test] +fn quickly_past_the_limit() { + let mut buf = HtmlWithLimit::new(6); + buf.open_tag("p"); + buf.push("Hello"); + buf.push(" World"); + // intentionally not closing

before finishing + assert_eq!(buf.finish(), "

Hello

"); +} + +#[test] +fn close_too_many() { + let mut buf = HtmlWithLimit::new(60); + buf.open_tag("p"); + buf.push("Hello"); + buf.close_tag(); + // This call does not panic because there are valid cases + // where `close_tag()` is called with no tags left to close. + // So `close_tag()` does nothing in this case. + buf.close_tag(); + assert_eq!(buf.finish(), "

Hello

"); +} diff --git a/src/librustdoc/html/markdown.rs b/src/librustdoc/html/markdown.rs new file mode 100644 index 000000000..52a2effca --- /dev/null +++ b/src/librustdoc/html/markdown.rs @@ -0,0 +1,1510 @@ +//! Markdown formatting for rustdoc. +//! +//! This module implements markdown formatting through the pulldown-cmark library. +//! +//! ``` +//! #![feature(rustc_private)] +//! +//! extern crate rustc_span; +//! +//! use rustc_span::edition::Edition; +//! use rustdoc::html::markdown::{HeadingOffset, IdMap, Markdown, ErrorCodes}; +//! +//! let s = "My *markdown* _text_"; +//! let mut id_map = IdMap::new(); +//! let md = Markdown { +//! content: s, +//! links: &[], +//! ids: &mut id_map, +//! error_codes: ErrorCodes::Yes, +//! edition: Edition::Edition2015, +//! playground: &None, +//! heading_offset: HeadingOffset::H2, +//! }; +//! let html = md.into_string(); +//! // ... something using html +//! ``` + +use rustc_data_structures::fx::FxHashMap; +use rustc_hir::def_id::DefId; +use rustc_hir::HirId; +use rustc_middle::ty::TyCtxt; +use rustc_span::edition::Edition; +use rustc_span::Span; + +use once_cell::sync::Lazy; +use std::borrow::Cow; +use std::cell::RefCell; +use std::collections::VecDeque; +use std::default::Default; +use std::fmt::Write; +use std::ops::{ControlFlow, Range}; +use std::str; + +use crate::clean::RenderedLink; +use crate::doctest; +use crate::html::escape::Escape; +use crate::html::format::Buffer; +use crate::html::highlight; +use crate::html::length_limit::HtmlWithLimit; +use crate::html::toc::TocBuilder; + +use pulldown_cmark::{ + html, BrokenLink, CodeBlockKind, CowStr, Event, LinkType, Options, Parser, Tag, +}; + +#[cfg(test)] +mod tests; + +const MAX_HEADER_LEVEL: u32 = 6; + +/// Options for rendering Markdown in the main body of documentation. +pub(crate) fn main_body_opts() -> Options { + Options::ENABLE_TABLES + | Options::ENABLE_FOOTNOTES + | Options::ENABLE_STRIKETHROUGH + | Options::ENABLE_TASKLISTS + | Options::ENABLE_SMART_PUNCTUATION +} + +/// Options for rendering Markdown in summaries (e.g., in search results). +pub(crate) fn summary_opts() -> Options { + Options::ENABLE_TABLES + | Options::ENABLE_FOOTNOTES + | Options::ENABLE_STRIKETHROUGH + | Options::ENABLE_TASKLISTS + | Options::ENABLE_SMART_PUNCTUATION +} + +#[derive(Debug, Clone, Copy)] +pub enum HeadingOffset { + H1 = 0, + H2, + H3, + H4, + H5, + H6, +} + +/// When `to_string` is called, this struct will emit the HTML corresponding to +/// the rendered version of the contained markdown string. +pub struct Markdown<'a> { + pub content: &'a str, + /// A list of link replacements. + pub links: &'a [RenderedLink], + /// The current list of used header IDs. + pub ids: &'a mut IdMap, + /// Whether to allow the use of explicit error codes in doctest lang strings. + pub error_codes: ErrorCodes, + /// Default edition to use when parsing doctests (to add a `fn main`). + pub edition: Edition, + pub playground: &'a Option, + /// Offset at which we render headings. + /// E.g. if `heading_offset: HeadingOffset::H2`, then `# something` renders an `

`. + pub heading_offset: HeadingOffset, +} +/// A tuple struct like `Markdown` that renders the markdown with a table of contents. +pub(crate) struct MarkdownWithToc<'a>( + pub(crate) &'a str, + pub(crate) &'a mut IdMap, + pub(crate) ErrorCodes, + pub(crate) Edition, + pub(crate) &'a Option, +); +/// A tuple struct like `Markdown` that renders the markdown escaping HTML tags. +pub(crate) struct MarkdownHtml<'a>( + pub(crate) &'a str, + pub(crate) &'a mut IdMap, + pub(crate) ErrorCodes, + pub(crate) Edition, + pub(crate) &'a Option, +); +/// A tuple struct like `Markdown` that renders only the first paragraph. +pub(crate) struct MarkdownSummaryLine<'a>(pub &'a str, pub &'a [RenderedLink]); + +#[derive(Copy, Clone, PartialEq, Debug)] +pub enum ErrorCodes { + Yes, + No, +} + +impl ErrorCodes { + pub(crate) fn from(b: bool) -> Self { + match b { + true => ErrorCodes::Yes, + false => ErrorCodes::No, + } + } + + pub(crate) fn as_bool(self) -> bool { + match self { + ErrorCodes::Yes => true, + ErrorCodes::No => false, + } + } +} + +/// Controls whether a line will be hidden or shown in HTML output. +/// +/// All lines are used in documentation tests. +enum Line<'a> { + Hidden(&'a str), + Shown(Cow<'a, str>), +} + +impl<'a> Line<'a> { + fn for_html(self) -> Option> { + match self { + Line::Shown(l) => Some(l), + Line::Hidden(_) => None, + } + } + + fn for_code(self) -> Cow<'a, str> { + match self { + Line::Shown(l) => l, + Line::Hidden(l) => Cow::Borrowed(l), + } + } +} + +// FIXME: There is a minor inconsistency here. For lines that start with ##, we +// have no easy way of removing a potential single space after the hashes, which +// is done in the single # case. This inconsistency seems okay, if non-ideal. In +// order to fix it we'd have to iterate to find the first non-# character, and +// then reallocate to remove it; which would make us return a String. +fn map_line(s: &str) -> Line<'_> { + let trimmed = s.trim(); + if trimmed.starts_with("##") { + Line::Shown(Cow::Owned(s.replacen("##", "#", 1))) + } else if let Some(stripped) = trimmed.strip_prefix("# ") { + // # text + Line::Hidden(stripped) + } else if trimmed == "#" { + // We cannot handle '#text' because it could be #[attr]. + Line::Hidden("") + } else { + Line::Shown(Cow::Borrowed(s)) + } +} + +/// Convert chars from a title for an id. +/// +/// "Hello, world!" -> "hello-world" +fn slugify(c: char) -> Option { + if c.is_alphanumeric() || c == '-' || c == '_' { + if c.is_ascii() { Some(c.to_ascii_lowercase()) } else { Some(c) } + } else if c.is_whitespace() && c.is_ascii() { + Some('-') + } else { + None + } +} + +#[derive(Clone, Debug)] +pub struct Playground { + pub crate_name: Option, + pub url: String, +} + +/// Adds syntax highlighting and playground Run buttons to Rust code blocks. +struct CodeBlocks<'p, 'a, I: Iterator>> { + inner: I, + check_error_codes: ErrorCodes, + edition: Edition, + // Information about the playground if a URL has been specified, containing an + // optional crate name and the URL. + playground: &'p Option, +} + +impl<'p, 'a, I: Iterator>> CodeBlocks<'p, 'a, I> { + fn new( + iter: I, + error_codes: ErrorCodes, + edition: Edition, + playground: &'p Option, + ) -> Self { + CodeBlocks { inner: iter, check_error_codes: error_codes, edition, playground } + } +} + +impl<'a, I: Iterator>> Iterator for CodeBlocks<'_, 'a, I> { + type Item = Event<'a>; + + fn next(&mut self) -> Option { + let event = self.inner.next(); + let compile_fail; + let should_panic; + let ignore; + let edition; + let Some(Event::Start(Tag::CodeBlock(kind))) = event else { + return event; + }; + + let mut origtext = String::new(); + for event in &mut self.inner { + match event { + Event::End(Tag::CodeBlock(..)) => break, + Event::Text(ref s) => { + origtext.push_str(s); + } + _ => {} + } + } + let lines = origtext.lines().filter_map(|l| map_line(l).for_html()); + let text = lines.intersperse("\n".into()).collect::(); + + let parse_result = match kind { + CodeBlockKind::Fenced(ref lang) => { + let parse_result = + LangString::parse_without_check(lang, self.check_error_codes, false); + if !parse_result.rust { + return Some(Event::Html( + format!( + "
\ + 
{}
\ +
", + lang, + Escape(&text), + ) + .into(), + )); + } + parse_result + } + CodeBlockKind::Indented => Default::default(), + }; + + compile_fail = parse_result.compile_fail; + should_panic = parse_result.should_panic; + ignore = parse_result.ignore; + edition = parse_result.edition; + + let explicit_edition = edition.is_some(); + let edition = edition.unwrap_or(self.edition); + + let playground_button = self.playground.as_ref().and_then(|playground| { + let krate = &playground.crate_name; + let url = &playground.url; + if url.is_empty() { + return None; + } + let test = origtext + .lines() + .map(|l| map_line(l).for_code()) + .intersperse("\n".into()) + .collect::(); + let krate = krate.as_ref().map(|s| &**s); + let (test, _, _) = + doctest::make_test(&test, krate, false, &Default::default(), edition, None); + let channel = if test.contains("#![feature(") { "&version=nightly" } else { "" }; + + // These characters don't need to be escaped in a URI. + // FIXME: use a library function for percent encoding. + fn dont_escape(c: u8) -> bool { + (b'a' <= c && c <= b'z') + || (b'A' <= c && c <= b'Z') + || (b'0' <= c && c <= b'9') + || c == b'-' + || c == b'_' + || c == b'.' + || c == b'~' + || c == b'!' + || c == b'\'' + || c == b'(' + || c == b')' + || c == b'*' + } + let mut test_escaped = String::new(); + for b in test.bytes() { + if dont_escape(b) { + test_escaped.push(char::from(b)); + } else { + write!(test_escaped, "%{:02X}", b).unwrap(); + } + } + Some(format!( + r#"Run"#, + url, test_escaped, channel, edition, + )) + }); + + let tooltip = if ignore != Ignore::None { + Some((None, "ignore")) + } else if compile_fail { + Some((None, "compile_fail")) + } else if should_panic { + Some((None, "should_panic")) + } else if explicit_edition { + Some((Some(edition), "edition")) + } else { + None + }; + + // insert newline to clearly separate it from the + // previous block so we can shorten the html output + let mut s = Buffer::new(); + s.push_str("\n"); + highlight::render_with_highlighting( + &text, + &mut s, + Some(&format!( + "rust-example-rendered{}", + if let Some((_, class)) = tooltip { format!(" {}", class) } else { String::new() } + )), + playground_button.as_deref(), + tooltip, + edition, + None, + None, + None, + ); + Some(Event::Html(s.into_inner().into())) + } +} + +/// Make headings links with anchor IDs and build up TOC. +struct LinkReplacer<'a, I: Iterator>> { + inner: I, + links: &'a [RenderedLink], + shortcut_link: Option<&'a RenderedLink>, +} + +impl<'a, I: Iterator>> LinkReplacer<'a, I> { + fn new(iter: I, links: &'a [RenderedLink]) -> Self { + LinkReplacer { inner: iter, links, shortcut_link: None } + } +} + +impl<'a, I: Iterator>> Iterator for LinkReplacer<'a, I> { + type Item = Event<'a>; + + fn next(&mut self) -> Option { + let mut event = self.inner.next(); + + // Replace intra-doc links and remove disambiguators from shortcut links (`[fn@f]`). + match &mut event { + // This is a shortcut link that was resolved by the broken_link_callback: `[fn@f]` + // Remove any disambiguator. + Some(Event::Start(Tag::Link( + // [fn@f] or [fn@f][] + LinkType::ShortcutUnknown | LinkType::CollapsedUnknown, + dest, + title, + ))) => { + debug!("saw start of shortcut link to {} with title {}", dest, title); + // If this is a shortcut link, it was resolved by the broken_link_callback. + // So the URL will already be updated properly. + let link = self.links.iter().find(|&link| *link.href == **dest); + // Since this is an external iterator, we can't replace the inner text just yet. + // Store that we saw a link so we know to replace it later. + if let Some(link) = link { + trace!("it matched"); + assert!(self.shortcut_link.is_none(), "shortcut links cannot be nested"); + self.shortcut_link = Some(link); + } + } + // Now that we're done with the shortcut link, don't replace any more text. + Some(Event::End(Tag::Link( + LinkType::ShortcutUnknown | LinkType::CollapsedUnknown, + dest, + _, + ))) => { + debug!("saw end of shortcut link to {}", dest); + if self.links.iter().any(|link| *link.href == **dest) { + assert!(self.shortcut_link.is_some(), "saw closing link without opening tag"); + self.shortcut_link = None; + } + } + // Handle backticks in inline code blocks, but only if we're in the middle of a shortcut link. + // [`fn@f`] + Some(Event::Code(text)) => { + trace!("saw code {}", text); + if let Some(link) = self.shortcut_link { + trace!("original text was {}", link.original_text); + // NOTE: this only replaces if the code block is the *entire* text. + // If only part of the link has code highlighting, the disambiguator will not be removed. + // e.g. [fn@`f`] + // This is a limitation from `collect_intra_doc_links`: it passes a full link, + // and does not distinguish at all between code blocks. + // So we could never be sure we weren't replacing too much: + // [fn@my_`f`unc] is treated the same as [my_func()] in that pass. + // + // NOTE: &[1..len() - 1] is to strip the backticks + if **text == link.original_text[1..link.original_text.len() - 1] { + debug!("replacing {} with {}", text, link.new_text); + *text = CowStr::Borrowed(&link.new_text); + } + } + } + // Replace plain text in links, but only in the middle of a shortcut link. + // [fn@f] + Some(Event::Text(text)) => { + trace!("saw text {}", text); + if let Some(link) = self.shortcut_link { + trace!("original text was {}", link.original_text); + // NOTE: same limitations as `Event::Code` + if **text == *link.original_text { + debug!("replacing {} with {}", text, link.new_text); + *text = CowStr::Borrowed(&link.new_text); + } + } + } + // If this is a link, but not a shortcut link, + // replace the URL, since the broken_link_callback was not called. + Some(Event::Start(Tag::Link(_, dest, _))) => { + if let Some(link) = self.links.iter().find(|&link| *link.original_text == **dest) { + *dest = CowStr::Borrowed(link.href.as_ref()); + } + } + // Anything else couldn't have been a valid Rust path, so no need to replace the text. + _ => {} + } + + // Yield the modified event + event + } +} + +/// Wrap HTML tables into `
` to prevent having the doc blocks width being too big. +struct TableWrapper<'a, I: Iterator>> { + inner: I, + stored_events: VecDeque>, +} + +impl<'a, I: Iterator>> TableWrapper<'a, I> { + fn new(iter: I) -> Self { + Self { inner: iter, stored_events: VecDeque::new() } + } +} + +impl<'a, I: Iterator>> Iterator for TableWrapper<'a, I> { + type Item = Event<'a>; + + fn next(&mut self) -> Option { + if let Some(first) = self.stored_events.pop_front() { + return Some(first); + } + + let event = self.inner.next()?; + + Some(match event { + Event::Start(Tag::Table(t)) => { + self.stored_events.push_back(Event::Start(Tag::Table(t))); + Event::Html(CowStr::Borrowed("
")) + } + Event::End(Tag::Table(t)) => { + self.stored_events.push_back(Event::Html(CowStr::Borrowed("
"))); + Event::End(Tag::Table(t)) + } + e => e, + }) + } +} + +type SpannedEvent<'a> = (Event<'a>, Range); + +/// Make headings links with anchor IDs and build up TOC. +struct HeadingLinks<'a, 'b, 'ids, I> { + inner: I, + toc: Option<&'b mut TocBuilder>, + buf: VecDeque>, + id_map: &'ids mut IdMap, + heading_offset: HeadingOffset, +} + +impl<'a, 'b, 'ids, I> HeadingLinks<'a, 'b, 'ids, I> { + fn new( + iter: I, + toc: Option<&'b mut TocBuilder>, + ids: &'ids mut IdMap, + heading_offset: HeadingOffset, + ) -> Self { + HeadingLinks { inner: iter, toc, buf: VecDeque::new(), id_map: ids, heading_offset } + } +} + +impl<'a, 'b, 'ids, I: Iterator>> Iterator + for HeadingLinks<'a, 'b, 'ids, I> +{ + type Item = SpannedEvent<'a>; + + fn next(&mut self) -> Option { + if let Some(e) = self.buf.pop_front() { + return Some(e); + } + + let event = self.inner.next(); + if let Some((Event::Start(Tag::Heading(level, _, _)), _)) = event { + let mut id = String::new(); + for event in &mut self.inner { + match &event.0 { + Event::End(Tag::Heading(..)) => break, + Event::Start(Tag::Link(_, _, _)) | Event::End(Tag::Link(..)) => {} + Event::Text(text) | Event::Code(text) => { + id.extend(text.chars().filter_map(slugify)); + self.buf.push_back(event); + } + _ => self.buf.push_back(event), + } + } + let id = self.id_map.derive(id); + + if let Some(ref mut builder) = self.toc { + let mut html_header = String::new(); + html::push_html(&mut html_header, self.buf.iter().map(|(ev, _)| ev.clone())); + let sec = builder.push(level as u32, html_header, id.clone()); + self.buf.push_front((Event::Html(format!("{} ", sec).into()), 0..0)); + } + + let level = + std::cmp::min(level as u32 + (self.heading_offset as u32), MAX_HEADER_LEVEL); + self.buf.push_back((Event::Html(format!("", level).into()), 0..0)); + + let start_tags = format!( + "\ + ", + id = id, + level = level + ); + return Some((Event::Html(start_tags.into()), 0..0)); + } + event + } +} + +/// Extracts just the first paragraph. +struct SummaryLine<'a, I: Iterator>> { + inner: I, + started: bool, + depth: u32, +} + +impl<'a, I: Iterator>> SummaryLine<'a, I> { + fn new(iter: I) -> Self { + SummaryLine { inner: iter, started: false, depth: 0 } + } +} + +fn check_if_allowed_tag(t: &Tag<'_>) -> bool { + matches!( + t, + Tag::Paragraph | Tag::Item | Tag::Emphasis | Tag::Strong | Tag::Link(..) | Tag::BlockQuote + ) +} + +fn is_forbidden_tag(t: &Tag<'_>) -> bool { + matches!(t, Tag::CodeBlock(_) | Tag::Table(_) | Tag::TableHead | Tag::TableRow | Tag::TableCell) +} + +impl<'a, I: Iterator>> Iterator for SummaryLine<'a, I> { + type Item = Event<'a>; + + fn next(&mut self) -> Option { + if self.started && self.depth == 0 { + return None; + } + if !self.started { + self.started = true; + } + if let Some(event) = self.inner.next() { + let mut is_start = true; + let is_allowed_tag = match event { + Event::Start(ref c) => { + if is_forbidden_tag(c) { + return None; + } + self.depth += 1; + check_if_allowed_tag(c) + } + Event::End(ref c) => { + if is_forbidden_tag(c) { + return None; + } + self.depth -= 1; + is_start = false; + check_if_allowed_tag(c) + } + _ => true, + }; + return if !is_allowed_tag { + if is_start { + Some(Event::Start(Tag::Paragraph)) + } else { + Some(Event::End(Tag::Paragraph)) + } + } else { + Some(event) + }; + } + None + } +} + +/// Moves all footnote definitions to the end and add back links to the +/// references. +struct Footnotes<'a, I> { + inner: I, + footnotes: FxHashMap>, u16)>, +} + +impl<'a, I> Footnotes<'a, I> { + fn new(iter: I) -> Self { + Footnotes { inner: iter, footnotes: FxHashMap::default() } + } + + fn get_entry(&mut self, key: &str) -> &mut (Vec>, u16) { + let new_id = self.footnotes.len() + 1; + let key = key.to_owned(); + self.footnotes.entry(key).or_insert((Vec::new(), new_id as u16)) + } +} + +impl<'a, I: Iterator>> Iterator for Footnotes<'a, I> { + type Item = SpannedEvent<'a>; + + fn next(&mut self) -> Option { + loop { + match self.inner.next() { + Some((Event::FootnoteReference(ref reference), range)) => { + let entry = self.get_entry(reference); + let reference = format!( + "{0}", + (*entry).1 + ); + return Some((Event::Html(reference.into()), range)); + } + Some((Event::Start(Tag::FootnoteDefinition(def)), _)) => { + let mut content = Vec::new(); + for (event, _) in &mut self.inner { + if let Event::End(Tag::FootnoteDefinition(..)) = event { + break; + } + content.push(event); + } + let entry = self.get_entry(&def); + (*entry).0 = content; + } + Some(e) => return Some(e), + None => { + if !self.footnotes.is_empty() { + let mut v: Vec<_> = self.footnotes.drain().map(|(_, x)| x).collect(); + v.sort_by(|a, b| a.1.cmp(&b.1)); + let mut ret = String::from("
    "); + for (mut content, id) in v { + write!(ret, "
  1. ", id).unwrap(); + let mut is_paragraph = false; + if let Some(&Event::End(Tag::Paragraph)) = content.last() { + content.pop(); + is_paragraph = true; + } + html::push_html(&mut ret, content.into_iter()); + write!(ret, " ↩", id).unwrap(); + if is_paragraph { + ret.push_str("

    "); + } + ret.push_str("
    2. "); + } + ret.push_str("
"); + return Some((Event::Html(ret.into()), 0..0)); + } else { + return None; + } + } + } + } + } +} + +pub(crate) fn find_testable_code( + doc: &str, + tests: &mut T, + error_codes: ErrorCodes, + enable_per_target_ignores: bool, + extra_info: Option<&ExtraInfo<'_>>, +) { + let mut parser = Parser::new(doc).into_offset_iter(); + let mut prev_offset = 0; + let mut nb_lines = 0; + let mut register_header = None; + while let Some((event, offset)) = parser.next() { + match event { + Event::Start(Tag::CodeBlock(kind)) => { + let block_info = match kind { + CodeBlockKind::Fenced(ref lang) => { + if lang.is_empty() { + Default::default() + } else { + LangString::parse( + lang, + error_codes, + enable_per_target_ignores, + extra_info, + ) + } + } + CodeBlockKind::Indented => Default::default(), + }; + if !block_info.rust { + continue; + } + + let mut test_s = String::new(); + + while let Some((Event::Text(s), _)) = parser.next() { + test_s.push_str(&s); + } + let text = test_s + .lines() + .map(|l| map_line(l).for_code()) + .collect::>>() + .join("\n"); + + nb_lines += doc[prev_offset..offset.start].lines().count(); + // If there are characters between the preceding line ending and + // this code block, `str::lines` will return an additional line, + // which we subtract here. + if nb_lines != 0 && !&doc[prev_offset..offset.start].ends_with('\n') { + nb_lines -= 1; + } + let line = tests.get_line() + nb_lines + 1; + tests.add_test(text, block_info, line); + prev_offset = offset.start; + } + Event::Start(Tag::Heading(level, _, _)) => { + register_header = Some(level as u32); + } + Event::Text(ref s) if register_header.is_some() => { + let level = register_header.unwrap(); + if s.is_empty() { + tests.register_header("", level); + } else { + tests.register_header(s, level); + } + register_header = None; + } + _ => {} + } + } +} + +pub(crate) struct ExtraInfo<'tcx> { + id: ExtraInfoId, + sp: Span, + tcx: TyCtxt<'tcx>, +} + +enum ExtraInfoId { + Hir(HirId), + Def(DefId), +} + +impl<'tcx> ExtraInfo<'tcx> { + pub(crate) fn new(tcx: TyCtxt<'tcx>, hir_id: HirId, sp: Span) -> ExtraInfo<'tcx> { + ExtraInfo { id: ExtraInfoId::Hir(hir_id), sp, tcx } + } + + pub(crate) fn new_did(tcx: TyCtxt<'tcx>, did: DefId, sp: Span) -> ExtraInfo<'tcx> { + ExtraInfo { id: ExtraInfoId::Def(did), sp, tcx } + } + + fn error_invalid_codeblock_attr(&self, msg: &str, help: &str) { + let hir_id = match self.id { + ExtraInfoId::Hir(hir_id) => hir_id, + ExtraInfoId::Def(item_did) => { + match item_did.as_local() { + Some(item_did) => self.tcx.hir().local_def_id_to_hir_id(item_did), + None => { + // If non-local, no need to check anything. + return; + } + } + } + }; + self.tcx.struct_span_lint_hir( + crate::lint::INVALID_CODEBLOCK_ATTRIBUTES, + hir_id, + self.sp, + |lint| { + let mut diag = lint.build(msg); + diag.help(help); + diag.emit(); + }, + ); + } +} + +#[derive(Eq, PartialEq, Clone, Debug)] +pub(crate) struct LangString { + original: String, + pub(crate) should_panic: bool, + pub(crate) no_run: bool, + pub(crate) ignore: Ignore, + pub(crate) rust: bool, + pub(crate) test_harness: bool, + pub(crate) compile_fail: bool, + pub(crate) error_codes: Vec, + pub(crate) edition: Option, +} + +#[derive(Eq, PartialEq, Clone, Debug)] +pub(crate) enum Ignore { + All, + None, + Some(Vec), +} + +impl Default for LangString { + fn default() -> Self { + Self { + original: String::new(), + should_panic: false, + no_run: false, + ignore: Ignore::None, + rust: true, + test_harness: false, + compile_fail: false, + error_codes: Vec::new(), + edition: None, + } + } +} + +impl LangString { + fn parse_without_check( + string: &str, + allow_error_code_check: ErrorCodes, + enable_per_target_ignores: bool, + ) -> LangString { + Self::parse(string, allow_error_code_check, enable_per_target_ignores, None) + } + + fn tokens(string: &str) -> impl Iterator { + // Pandoc, which Rust once used for generating documentation, + // expects lang strings to be surrounded by `{}` and for each token + // to be proceeded by a `.`. Since some of these lang strings are still + // loose in the wild, we strip a pair of surrounding `{}` from the lang + // string and a leading `.` from each token. + + let string = string.trim(); + + let first = string.chars().next(); + let last = string.chars().last(); + + let string = if first == Some('{') && last == Some('}') { + &string[1..string.len() - 1] + } else { + string + }; + + string + .split(|c| c == ',' || c == ' ' || c == '\t') + .map(str::trim) + .map(|token| token.strip_prefix('.').unwrap_or(token)) + .filter(|token| !token.is_empty()) + } + + fn parse( + string: &str, + allow_error_code_check: ErrorCodes, + enable_per_target_ignores: bool, + extra: Option<&ExtraInfo<'_>>, + ) -> LangString { + let allow_error_code_check = allow_error_code_check.as_bool(); + let mut seen_rust_tags = false; + let mut seen_other_tags = false; + let mut data = LangString::default(); + let mut ignores = vec![]; + + data.original = string.to_owned(); + + for token in Self::tokens(string) { + match token { + "should_panic" => { + data.should_panic = true; + seen_rust_tags = !seen_other_tags; + } + "no_run" => { + data.no_run = true; + seen_rust_tags = !seen_other_tags; + } + "ignore" => { + data.ignore = Ignore::All; + seen_rust_tags = !seen_other_tags; + } + x if x.starts_with("ignore-") => { + if enable_per_target_ignores { + ignores.push(x.trim_start_matches("ignore-").to_owned()); + seen_rust_tags = !seen_other_tags; + } + } + "rust" => { + data.rust = true; + seen_rust_tags = true; + } + "test_harness" => { + data.test_harness = true; + seen_rust_tags = !seen_other_tags || seen_rust_tags; + } + "compile_fail" => { + data.compile_fail = true; + seen_rust_tags = !seen_other_tags || seen_rust_tags; + data.no_run = true; + } + x if x.starts_with("edition") => { + data.edition = x[7..].parse::().ok(); + } + x if allow_error_code_check && x.starts_with('E') && x.len() == 5 => { + if x[1..].parse::().is_ok() { + data.error_codes.push(x.to_owned()); + seen_rust_tags = !seen_other_tags || seen_rust_tags; + } else { + seen_other_tags = true; + } + } + x if extra.is_some() => { + let s = x.to_lowercase(); + if let Some((flag, help)) = if s == "compile-fail" + || s == "compile_fail" + || s == "compilefail" + { + Some(( + "compile_fail", + "the code block will either not be tested if not marked as a rust one \ + or won't fail if it compiles successfully", + )) + } else if s == "should-panic" || s == "should_panic" || s == "shouldpanic" { + Some(( + "should_panic", + "the code block will either not be tested if not marked as a rust one \ + or won't fail if it doesn't panic when running", + )) + } else if s == "no-run" || s == "no_run" || s == "norun" { + Some(( + "no_run", + "the code block will either not be tested if not marked as a rust one \ + or will be run (which you might not want)", + )) + } else if s == "test-harness" || s == "test_harness" || s == "testharness" { + Some(( + "test_harness", + "the code block will either not be tested if not marked as a rust one \ + or the code will be wrapped inside a main function", + )) + } else { + None + } { + if let Some(extra) = extra { + extra.error_invalid_codeblock_attr( + &format!("unknown attribute `{}`. Did you mean `{}`?", x, flag), + help, + ); + } + } + seen_other_tags = true; + } + _ => seen_other_tags = true, + } + } + + // ignore-foo overrides ignore + if !ignores.is_empty() { + data.ignore = Ignore::Some(ignores); + } + + data.rust &= !seen_other_tags || seen_rust_tags; + + data + } +} + +impl Markdown<'_> { + pub fn into_string(self) -> String { + let Markdown { + content: md, + links, + ids, + error_codes: codes, + edition, + playground, + heading_offset, + } = self; + + // This is actually common enough to special-case + if md.is_empty() { + return String::new(); + } + let mut replacer = |broken_link: BrokenLink<'_>| { + links + .iter() + .find(|link| link.original_text.as_str() == &*broken_link.reference) + .map(|link| (link.href.as_str().into(), link.new_text.as_str().into())) + }; + + let p = Parser::new_with_broken_link_callback(md, main_body_opts(), Some(&mut replacer)); + let p = p.into_offset_iter(); + + let mut s = String::with_capacity(md.len() * 3 / 2); + + let p = HeadingLinks::new(p, None, ids, heading_offset); + let p = Footnotes::new(p); + let p = LinkReplacer::new(p.map(|(ev, _)| ev), links); + let p = TableWrapper::new(p); + let p = CodeBlocks::new(p, codes, edition, playground); + html::push_html(&mut s, p); + + s + } +} + +impl MarkdownWithToc<'_> { + pub(crate) fn into_string(self) -> String { + let MarkdownWithToc(md, ids, codes, edition, playground) = self; + + let p = Parser::new_ext(md, main_body_opts()).into_offset_iter(); + + let mut s = String::with_capacity(md.len() * 3 / 2); + + let mut toc = TocBuilder::new(); + + { + let p = HeadingLinks::new(p, Some(&mut toc), ids, HeadingOffset::H1); + let p = Footnotes::new(p); + let p = TableWrapper::new(p.map(|(ev, _)| ev)); + let p = CodeBlocks::new(p, codes, edition, playground); + html::push_html(&mut s, p); + } + + format!("{}", toc.into_toc().print(), s) + } +} + +impl MarkdownHtml<'_> { + pub(crate) fn into_string(self) -> String { + let MarkdownHtml(md, ids, codes, edition, playground) = self; + + // This is actually common enough to special-case + if md.is_empty() { + return String::new(); + } + let p = Parser::new_ext(md, main_body_opts()).into_offset_iter(); + + // Treat inline HTML as plain text. + let p = p.map(|event| match event.0 { + Event::Html(text) => (Event::Text(text), event.1), + _ => event, + }); + + let mut s = String::with_capacity(md.len() * 3 / 2); + + let p = HeadingLinks::new(p, None, ids, HeadingOffset::H1); + let p = Footnotes::new(p); + let p = TableWrapper::new(p.map(|(ev, _)| ev)); + let p = CodeBlocks::new(p, codes, edition, playground); + html::push_html(&mut s, p); + + s + } +} + +impl MarkdownSummaryLine<'_> { + pub(crate) fn into_string(self) -> String { + let MarkdownSummaryLine(md, links) = self; + // This is actually common enough to special-case + if md.is_empty() { + return String::new(); + } + + let mut replacer = |broken_link: BrokenLink<'_>| { + links + .iter() + .find(|link| link.original_text.as_str() == &*broken_link.reference) + .map(|link| (link.href.as_str().into(), link.new_text.as_str().into())) + }; + + let p = Parser::new_with_broken_link_callback(md, summary_opts(), Some(&mut replacer)); + + let mut s = String::new(); + + html::push_html(&mut s, LinkReplacer::new(SummaryLine::new(p), links)); + + s + } +} + +/// Renders a subset of Markdown in the first paragraph of the provided Markdown. +/// +/// - *Italics*, **bold**, and `inline code` styles **are** rendered. +/// - Headings and links are stripped (though the text *is* rendered). +/// - HTML, code blocks, and everything else are ignored. +/// +/// Returns a tuple of the rendered HTML string and whether the output was shortened +/// due to the provided `length_limit`. +fn markdown_summary_with_limit( + md: &str, + link_names: &[RenderedLink], + length_limit: usize, +) -> (String, bool) { + if md.is_empty() { + return (String::new(), false); + } + + let mut replacer = |broken_link: BrokenLink<'_>| { + link_names + .iter() + .find(|link| link.original_text.as_str() == &*broken_link.reference) + .map(|link| (link.href.as_str().into(), link.new_text.as_str().into())) + }; + + let p = Parser::new_with_broken_link_callback(md, summary_opts(), Some(&mut replacer)); + let mut p = LinkReplacer::new(p, link_names); + + let mut buf = HtmlWithLimit::new(length_limit); + let mut stopped_early = false; + p.try_for_each(|event| { + match &event { + Event::Text(text) => { + let r = + text.split_inclusive(char::is_whitespace).try_for_each(|word| buf.push(word)); + if r.is_break() { + stopped_early = true; + } + return r; + } + Event::Code(code) => { + buf.open_tag("code"); + let r = buf.push(code); + if r.is_break() { + stopped_early = true; + } else { + buf.close_tag(); + } + return r; + } + Event::Start(tag) => match tag { + Tag::Emphasis => buf.open_tag("em"), + Tag::Strong => buf.open_tag("strong"), + Tag::CodeBlock(..) => return ControlFlow::BREAK, + _ => {} + }, + Event::End(tag) => match tag { + Tag::Emphasis | Tag::Strong => buf.close_tag(), + Tag::Paragraph | Tag::Heading(..) => return ControlFlow::BREAK, + _ => {} + }, + Event::HardBreak | Event::SoftBreak => buf.push(" ")?, + _ => {} + }; + ControlFlow::CONTINUE + }); + + (buf.finish(), stopped_early) +} + +/// Renders a shortened first paragraph of the given Markdown as a subset of Markdown, +/// making it suitable for contexts like the search index. +/// +/// Will shorten to 59 or 60 characters, including an ellipsis (…) if it was shortened. +/// +/// See [`markdown_summary_with_limit`] for details about what is rendered and what is not. +pub(crate) fn short_markdown_summary(markdown: &str, link_names: &[RenderedLink]) -> String { + let (mut s, was_shortened) = markdown_summary_with_limit(markdown, link_names, 59); + + if was_shortened { + s.push('…'); + } + + s +} + +/// Renders the first paragraph of the provided markdown as plain text. +/// Useful for alt-text. +/// +/// - Headings, links, and formatting are stripped. +/// - Inline code is rendered as-is, surrounded by backticks. +/// - HTML and code blocks are ignored. +pub(crate) fn plain_text_summary(md: &str) -> String { + if md.is_empty() { + return String::new(); + } + + let mut s = String::with_capacity(md.len() * 3 / 2); + + for event in Parser::new_ext(md, summary_opts()) { + match &event { + Event::Text(text) => s.push_str(text), + Event::Code(code) => { + s.push('`'); + s.push_str(code); + s.push('`'); + } + Event::HardBreak | Event::SoftBreak => s.push(' '), + Event::Start(Tag::CodeBlock(..)) => break, + Event::End(Tag::Paragraph) => break, + Event::End(Tag::Heading(..)) => break, + _ => (), + } + } + + s +} + +#[derive(Debug)] +pub(crate) struct MarkdownLink { + pub kind: LinkType, + pub link: String, + pub range: Range, +} + +pub(crate) fn markdown_links( + md: &str, + filter_map: impl Fn(MarkdownLink) -> Option, +) -> Vec { + if md.is_empty() { + return vec![]; + } + + let links = RefCell::new(vec![]); + + // FIXME: remove this function once pulldown_cmark can provide spans for link definitions. + let locate = |s: &str, fallback: Range| unsafe { + let s_start = s.as_ptr(); + let s_end = s_start.add(s.len()); + let md_start = md.as_ptr(); + let md_end = md_start.add(md.len()); + if md_start <= s_start && s_end <= md_end { + let start = s_start.offset_from(md_start) as usize; + let end = s_end.offset_from(md_start) as usize; + start..end + } else { + fallback + } + }; + + let span_for_link = |link: &CowStr<'_>, span: Range| { + // For diagnostics, we want to underline the link's definition but `span` will point at + // where the link is used. This is a problem for reference-style links, where the definition + // is separate from the usage. + match link { + // `Borrowed` variant means the string (the link's destination) may come directly from + // the markdown text and we can locate the original link destination. + // NOTE: LinkReplacer also provides `Borrowed` but possibly from other sources, + // so `locate()` can fall back to use `span`. + CowStr::Borrowed(s) => locate(s, span), + + // For anything else, we can only use the provided range. + CowStr::Boxed(_) | CowStr::Inlined(_) => span, + } + }; + + let mut push = |link: BrokenLink<'_>| { + let span = span_for_link(&link.reference, link.span); + filter_map(MarkdownLink { + kind: LinkType::ShortcutUnknown, + link: link.reference.to_string(), + range: span, + }) + .map(|link| links.borrow_mut().push(link)); + None + }; + let p = Parser::new_with_broken_link_callback(md, main_body_opts(), Some(&mut push)) + .into_offset_iter(); + + // There's no need to thread an IdMap through to here because + // the IDs generated aren't going to be emitted anywhere. + let mut ids = IdMap::new(); + let iter = Footnotes::new(HeadingLinks::new(p, None, &mut ids, HeadingOffset::H1)); + + for ev in iter { + if let Event::Start(Tag::Link( + // `<>` links cannot be intra-doc links so we skip them. + kind @ (LinkType::Inline + | LinkType::Reference + | LinkType::ReferenceUnknown + | LinkType::Collapsed + | LinkType::CollapsedUnknown + | LinkType::Shortcut + | LinkType::ShortcutUnknown), + dest, + _, + )) = ev.0 + { + debug!("found link: {dest}"); + let span = span_for_link(&dest, ev.1); + filter_map(MarkdownLink { kind, link: dest.into_string(), range: span }) + .map(|link| links.borrow_mut().push(link)); + } + } + + links.into_inner() +} + +#[derive(Debug)] +pub(crate) struct RustCodeBlock { + /// The range in the markdown that the code block occupies. Note that this includes the fences + /// for fenced code blocks. + pub(crate) range: Range, + /// The range in the markdown that the code within the code block occupies. + pub(crate) code: Range, + pub(crate) is_fenced: bool, + pub(crate) lang_string: LangString, +} + +/// Returns a range of bytes for each code block in the markdown that is tagged as `rust` or +/// untagged (and assumed to be rust). +pub(crate) fn rust_code_blocks(md: &str, extra_info: &ExtraInfo<'_>) -> Vec { + let mut code_blocks = vec![]; + + if md.is_empty() { + return code_blocks; + } + + let mut p = Parser::new_ext(md, main_body_opts()).into_offset_iter(); + + while let Some((event, offset)) = p.next() { + if let Event::Start(Tag::CodeBlock(syntax)) = event { + let (lang_string, code_start, code_end, range, is_fenced) = match syntax { + CodeBlockKind::Fenced(syntax) => { + let syntax = syntax.as_ref(); + let lang_string = if syntax.is_empty() { + Default::default() + } else { + LangString::parse(&*syntax, ErrorCodes::Yes, false, Some(extra_info)) + }; + if !lang_string.rust { + continue; + } + let (code_start, mut code_end) = match p.next() { + Some((Event::Text(_), offset)) => (offset.start, offset.end), + Some((_, sub_offset)) => { + let code = Range { start: sub_offset.start, end: sub_offset.start }; + code_blocks.push(RustCodeBlock { + is_fenced: true, + range: offset, + code, + lang_string, + }); + continue; + } + None => { + let code = Range { start: offset.end, end: offset.end }; + code_blocks.push(RustCodeBlock { + is_fenced: true, + range: offset, + code, + lang_string, + }); + continue; + } + }; + while let Some((Event::Text(_), offset)) = p.next() { + code_end = offset.end; + } + (lang_string, code_start, code_end, offset, true) + } + CodeBlockKind::Indented => { + // The ending of the offset goes too far sometime so we reduce it by one in + // these cases. + if offset.end > offset.start && md.get(offset.end..=offset.end) == Some("\n") { + ( + LangString::default(), + offset.start, + offset.end, + Range { start: offset.start, end: offset.end - 1 }, + false, + ) + } else { + (LangString::default(), offset.start, offset.end, offset, false) + } + } + }; + + code_blocks.push(RustCodeBlock { + is_fenced, + range, + code: Range { start: code_start, end: code_end }, + lang_string, + }); + } + } + + code_blocks +} + +#[derive(Clone, Default, Debug)] +pub struct IdMap { + map: FxHashMap, usize>, +} + +// The map is pre-initialized and cloned each time to avoid reinitializing it repeatedly. +static DEFAULT_ID_MAP: Lazy, usize>> = Lazy::new(|| init_id_map()); + +fn init_id_map() -> FxHashMap, usize> { + let mut map = FxHashMap::default(); + // This is the list of IDs used in Javascript. + map.insert("settings".into(), 1); + map.insert("not-displayed".into(), 1); + map.insert("alternative-display".into(), 1); + map.insert("search".into(), 1); + // This is the list of IDs used in HTML generated in Rust (including the ones + // used in tera template files). + map.insert("mainThemeStyle".into(), 1); + map.insert("themeStyle".into(), 1); + map.insert("settings-menu".into(), 1); + map.insert("help-button".into(), 1); + map.insert("main-content".into(), 1); + map.insert("crate-search".into(), 1); + map.insert("toggle-all-docs".into(), 1); + map.insert("all-types".into(), 1); + map.insert("default-settings".into(), 1); + map.insert("rustdoc-vars".into(), 1); + map.insert("sidebar-vars".into(), 1); + map.insert("copy-path".into(), 1); + map.insert("TOC".into(), 1); + // This is the list of IDs used by rustdoc sections (but still generated by + // rustdoc). + map.insert("fields".into(), 1); + map.insert("variants".into(), 1); + map.insert("implementors-list".into(), 1); + map.insert("synthetic-implementors-list".into(), 1); + map.insert("foreign-impls".into(), 1); + map.insert("implementations".into(), 1); + map.insert("trait-implementations".into(), 1); + map.insert("synthetic-implementations".into(), 1); + map.insert("blanket-implementations".into(), 1); + map.insert("required-associated-types".into(), 1); + map.insert("provided-associated-types".into(), 1); + map.insert("provided-associated-consts".into(), 1); + map.insert("required-associated-consts".into(), 1); + map.insert("required-methods".into(), 1); + map.insert("provided-methods".into(), 1); + map.insert("implementors".into(), 1); + map.insert("synthetic-implementors".into(), 1); + map.insert("implementations-list".into(), 1); + map.insert("trait-implementations-list".into(), 1); + map.insert("synthetic-implementations-list".into(), 1); + map.insert("blanket-implementations-list".into(), 1); + map.insert("deref-methods".into(), 1); + map.insert("layout".into(), 1); + map +} + +impl IdMap { + pub fn new() -> Self { + IdMap { map: DEFAULT_ID_MAP.clone() } + } + + pub(crate) fn derive + ToString>(&mut self, candidate: S) -> String { + let id = match self.map.get_mut(candidate.as_ref()) { + None => candidate.to_string(), + Some(a) => { + let id = format!("{}-{}", candidate.as_ref(), *a); + *a += 1; + id + } + }; + + self.map.insert(id.clone().into(), 1); + id + } +} diff --git a/src/librustdoc/html/markdown/tests.rs b/src/librustdoc/html/markdown/tests.rs new file mode 100644 index 000000000..5c0bf0ed9 --- /dev/null +++ b/src/librustdoc/html/markdown/tests.rs @@ -0,0 +1,312 @@ +use super::{find_testable_code, plain_text_summary, short_markdown_summary}; +use super::{ErrorCodes, HeadingOffset, IdMap, Ignore, LangString, Markdown, MarkdownHtml}; +use rustc_span::edition::{Edition, DEFAULT_EDITION}; + +#[test] +fn test_unique_id() { + let input = [ + "foo", + "examples", + "examples", + "method.into_iter", + "examples", + "method.into_iter", + "foo", + "main-content", + "search", + "methods", + "examples", + "method.into_iter", + "assoc_type.Item", + "assoc_type.Item", + ]; + let expected = [ + "foo", + "examples", + "examples-1", + "method.into_iter", + "examples-2", + "method.into_iter-1", + "foo-1", + "main-content-1", + "search-1", + "methods", + "examples-3", + "method.into_iter-2", + "assoc_type.Item", + "assoc_type.Item-1", + ]; + + let mut map = IdMap::new(); + let actual: Vec = input.iter().map(|s| map.derive(s.to_string())).collect(); + assert_eq!(&actual[..], expected); +} + +#[test] +fn test_lang_string_parse() { + fn t(lg: LangString) { + let s = &lg.original; + assert_eq!(LangString::parse(s, ErrorCodes::Yes, true, None), lg) + } + + t(Default::default()); + t(LangString { original: "rust".into(), ..Default::default() }); + t(LangString { original: ".rust".into(), ..Default::default() }); + t(LangString { original: "{rust}".into(), ..Default::default() }); + t(LangString { original: "{.rust}".into(), ..Default::default() }); + t(LangString { original: "sh".into(), rust: false, ..Default::default() }); + t(LangString { original: "ignore".into(), ignore: Ignore::All, ..Default::default() }); + t(LangString { + original: "ignore-foo".into(), + ignore: Ignore::Some(vec!["foo".to_string()]), + ..Default::default() + }); + t(LangString { original: "should_panic".into(), should_panic: true, ..Default::default() }); + t(LangString { original: "no_run".into(), no_run: true, ..Default::default() }); + t(LangString { original: "test_harness".into(), test_harness: true, ..Default::default() }); + t(LangString { + original: "compile_fail".into(), + no_run: true, + compile_fail: true, + ..Default::default() + }); + t(LangString { original: "no_run,example".into(), no_run: true, ..Default::default() }); + t(LangString { + original: "sh,should_panic".into(), + should_panic: true, + rust: false, + ..Default::default() + }); + t(LangString { original: "example,rust".into(), ..Default::default() }); + t(LangString { + original: "test_harness,.rust".into(), + test_harness: true, + ..Default::default() + }); + t(LangString { + original: "text, no_run".into(), + no_run: true, + rust: false, + ..Default::default() + }); + t(LangString { + original: "text,no_run".into(), + no_run: true, + rust: false, + ..Default::default() + }); + t(LangString { + original: "text,no_run, ".into(), + no_run: true, + rust: false, + ..Default::default() + }); + t(LangString { + original: "text,no_run,".into(), + no_run: true, + rust: false, + ..Default::default() + }); + t(LangString { + original: "edition2015".into(), + edition: Some(Edition::Edition2015), + ..Default::default() + }); + t(LangString { + original: "edition2018".into(), + edition: Some(Edition::Edition2018), + ..Default::default() + }); +} + +#[test] +fn test_lang_string_tokenizer() { + fn case(lang_string: &str, want: &[&str]) { + let have = LangString::tokens(lang_string).collect::>(); + assert_eq!(have, want, "Unexpected lang string split for `{}`", lang_string); + } + + case("", &[]); + case("foo", &["foo"]); + case("foo,bar", &["foo", "bar"]); + case(".foo,.bar", &["foo", "bar"]); + case("{.foo,.bar}", &["foo", "bar"]); + case(" {.foo,.bar} ", &["foo", "bar"]); + case("foo bar", &["foo", "bar"]); + case("foo\tbar", &["foo", "bar"]); + case("foo\t, bar", &["foo", "bar"]); + case(" foo , bar ", &["foo", "bar"]); + case(",,foo,,bar,,", &["foo", "bar"]); + case("foo=bar", &["foo=bar"]); + case("a-b-c", &["a-b-c"]); + case("a_b_c", &["a_b_c"]); +} + +#[test] +fn test_header() { + fn t(input: &str, expect: &str) { + let mut map = IdMap::new(); + let output = Markdown { + content: input, + links: &[], + ids: &mut map, + error_codes: ErrorCodes::Yes, + edition: DEFAULT_EDITION, + playground: &None, + heading_offset: HeadingOffset::H2, + } + .into_string(); + assert_eq!(output, expect, "original: {}", input); + } + + t("# Foo bar", "

Foo bar

"); + t( + "## Foo-bar_baz qux", + "

\ + Foo-bar_baz qux

", + ); + t( + "### **Foo** *bar* baz!?!& -_qux_-%", + "

\ + Foo \ + bar baz!?!& -qux-%\ +

", + ); + t( + "#### **Foo?** & \\*bar?!* _`baz`_ ❤ #qux", + "
\ + Foo? & *bar?!* \ + baz ❤ #qux\ +
", + ); +} + +#[test] +fn test_header_ids_multiple_blocks() { + let mut map = IdMap::new(); + fn t(map: &mut IdMap, input: &str, expect: &str) { + let output = Markdown { + content: input, + links: &[], + ids: map, + error_codes: ErrorCodes::Yes, + edition: DEFAULT_EDITION, + playground: &None, + heading_offset: HeadingOffset::H2, + } + .into_string(); + assert_eq!(output, expect, "original: {}", input); + } + + t(&mut map, "# Example", "

Example

"); + t(&mut map, "# Panics", "

Panics

"); + t(&mut map, "# Example", "

Example

"); + t(&mut map, "# Search", "

Search

"); + t(&mut map, "# Example", "

Example

"); + t(&mut map, "# Panics", "

Panics

"); +} + +#[test] +fn test_short_markdown_summary() { + fn t(input: &str, expect: &str) { + let output = short_markdown_summary(input, &[][..]); + assert_eq!(output, expect, "original: {}", input); + } + + t("", ""); + t("hello [Rust](https://www.rust-lang.org) :)", "hello Rust :)"); + t("*italic*", "italic"); + t("**bold**", "bold"); + t("Multi-line\nsummary", "Multi-line summary"); + t("Hard-break \nsummary", "Hard-break summary"); + t("hello [Rust] :)\n\n[Rust]: https://www.rust-lang.org", "hello Rust :)"); + t("hello [Rust](https://www.rust-lang.org \"Rust\") :)", "hello Rust :)"); + t("dud [link]", "dud [link]"); + t("code `let x = i32;` ...", "code let x = i32; …"); + t("type `Type<'static>` ...", "type Type<'static> …"); + // Test to ensure escaping and length-limiting work well together. + // The output should be limited based on the input length, + // rather than the output, because escaped versions of characters + // are usually longer than how the character is actually displayed. + t( + "& & & & & & & & & & & & & & & & & & & & & & & & & & & & & & & & & & & & &", + "& & & & & & & & & & & & \ + & & & & & & & & & & & & \ + & & & & & …", + ); + t("# top header", "top header"); + t("# top header\n\nfollowed by a paragraph", "top header"); + t("## header", "header"); + t("first paragraph\n\nsecond paragraph", "first paragraph"); + t("```\nfn main() {}\n```", ""); + t("
hello
", ""); + t( + "a *very*, **very** long first paragraph. it has lots of `inline code: Vec`. and it has a [link](https://www.rust-lang.org).\nthat was a soft line break! \nthat was a hard one\n\nsecond paragraph.", + "a very, very long first paragraph. it has lots of …", + ); +} + +#[test] +fn test_plain_text_summary() { + fn t(input: &str, expect: &str) { + let output = plain_text_summary(input); + assert_eq!(output, expect, "original: {}", input); + } + + t("", ""); + t("hello [Rust](https://www.rust-lang.org) :)", "hello Rust :)"); + t("**bold**", "bold"); + t("Multi-line\nsummary", "Multi-line summary"); + t("Hard-break \nsummary", "Hard-break summary"); + t("hello [Rust] :)\n\n[Rust]: https://www.rust-lang.org", "hello Rust :)"); + t("hello [Rust](https://www.rust-lang.org \"Rust\") :)", "hello Rust :)"); + t("dud [link]", "dud [link]"); + t("code `let x = i32;` ...", "code `let x = i32;` …"); + t("type `Type<'static>` ...", "type `Type<'static>` …"); + t("# top header", "top header"); + t("# top header\n\nfollowed by some text", "top header"); + t("## header", "header"); + t("first paragraph\n\nsecond paragraph", "first paragraph"); + t("```\nfn main() {}\n```", ""); + t("
hello
", ""); + t( + "a *very*, **very** long first paragraph. it has lots of `inline code: Vec`. and it has a [link](https://www.rust-lang.org).\nthat was a soft line break! \nthat was a hard one\n\nsecond paragraph.", + "a very, very long first paragraph. it has lots of `inline code: Vec`. and it has a link. that was a soft line break! that was a hard one", + ); +} + +#[test] +fn test_markdown_html_escape() { + fn t(input: &str, expect: &str) { + let mut idmap = IdMap::new(); + let output = + MarkdownHtml(input, &mut idmap, ErrorCodes::Yes, DEFAULT_EDITION, &None).into_string(); + assert_eq!(output, expect, "original: {}", input); + } + + t("`Struct<'a, T>`", "

Struct<'a, T>

\n"); + t("Struct<'a, T>", "

Struct<’a, T>

\n"); + t("Struct
", "

Struct<br>

\n"); +} + +#[test] +fn test_find_testable_code_line() { + fn t(input: &str, expect: &[usize]) { + impl crate::doctest::Tester for Vec { + fn add_test(&mut self, _test: String, _config: LangString, line: usize) { + self.push(line); + } + } + let mut lines = Vec::::new(); + find_testable_code(input, &mut lines, ErrorCodes::No, false, None); + assert_eq!(lines, expect); + } + + t("", &[]); + t("```rust\n```", &[1]); + t(" ```rust\n```", &[1]); + t("\n```rust\n```", &[2]); + t("\n ```rust\n```", &[2]); + t("```rust\n```\n```rust\n```", &[1, 3]); + t("```rust\n```\n ```rust\n```", &[1, 3]); +} diff --git a/src/librustdoc/html/mod.rs b/src/librustdoc/html/mod.rs new file mode 100644 index 000000000..481ed16c0 --- /dev/null +++ b/src/librustdoc/html/mod.rs @@ -0,0 +1,15 @@ +pub(crate) mod escape; +pub(crate) mod format; +pub(crate) mod highlight; +pub(crate) mod layout; +mod length_limit; +// used by the error-index generator, so it needs to be public +pub mod markdown; +pub(crate) mod render; +pub(crate) mod sources; +pub(crate) mod static_files; +pub(crate) mod toc; +mod url_parts_builder; + +#[cfg(test)] +mod tests; diff --git a/src/librustdoc/html/render/context.rs b/src/librustdoc/html/render/context.rs new file mode 100644 index 000000000..2ed7a6f1b --- /dev/null +++ b/src/librustdoc/html/render/context.rs @@ -0,0 +1,762 @@ +use std::cell::RefCell; +use std::collections::BTreeMap; +use std::io; +use std::path::{Path, PathBuf}; +use std::rc::Rc; +use std::sync::mpsc::{channel, Receiver}; + +use rustc_data_structures::fx::{FxHashMap, FxHashSet}; +use rustc_hir::def_id::{DefId, LOCAL_CRATE}; +use rustc_middle::ty::TyCtxt; +use rustc_session::Session; +use rustc_span::edition::Edition; +use rustc_span::source_map::FileName; +use rustc_span::{sym, Symbol}; + +use super::print_item::{full_path, item_path, print_item}; +use super::search_index::build_index; +use super::write_shared::write_shared; +use super::{ + collect_spans_and_sources, print_sidebar, scrape_examples_help, AllTypes, LinkFromSrc, NameDoc, + StylePath, BASIC_KEYWORDS, +}; + +use crate::clean::{self, types::ExternalLocation, ExternalCrate}; +use crate::config::{ModuleSorting, RenderOptions}; +use crate::docfs::{DocFS, PathError}; +use crate::error::Error; +use crate::formats::cache::Cache; +use crate::formats::item_type::ItemType; +use crate::formats::FormatRenderer; +use crate::html::escape::Escape; +use crate::html::format::{join_with_double_colon, Buffer}; +use crate::html::markdown::{self, plain_text_summary, ErrorCodes, IdMap}; +use crate::html::{layout, sources}; +use crate::scrape_examples::AllCallLocations; +use crate::try_err; + +/// Major driving force in all rustdoc rendering. This contains information +/// about where in the tree-like hierarchy rendering is occurring and controls +/// how the current page is being rendered. +/// +/// It is intended that this context is a lightweight object which can be fairly +/// easily cloned because it is cloned per work-job (about once per item in the +/// rustdoc tree). +pub(crate) struct Context<'tcx> { + /// Current hierarchy of components leading down to what's currently being + /// rendered + pub(crate) current: Vec, + /// The current destination folder of where HTML artifacts should be placed. + /// This changes as the context descends into the module hierarchy. + pub(crate) dst: PathBuf, + /// A flag, which when `true`, will render pages which redirect to the + /// real location of an item. This is used to allow external links to + /// publicly reused items to redirect to the right location. + pub(super) render_redirect_pages: bool, + /// Tracks section IDs for `Deref` targets so they match in both the main + /// body and the sidebar. + pub(super) deref_id_map: FxHashMap, + /// The map used to ensure all generated 'id=' attributes are unique. + pub(super) id_map: IdMap, + /// Shared mutable state. + /// + /// Issue for improving the situation: [#82381][] + /// + /// [#82381]: https://github.com/rust-lang/rust/issues/82381 + pub(crate) shared: Rc>, + /// This flag indicates whether source links should be generated or not. If + /// the source files are present in the html rendering, then this will be + /// `true`. + pub(crate) include_sources: bool, +} + +// `Context` is cloned a lot, so we don't want the size to grow unexpectedly. +#[cfg(all(target_arch = "x86_64", target_pointer_width = "64"))] +rustc_data_structures::static_assert_size!(Context<'_>, 128); + +/// Shared mutable state used in [`Context`] and elsewhere. +pub(crate) struct SharedContext<'tcx> { + pub(crate) tcx: TyCtxt<'tcx>, + /// The path to the crate root source minus the file name. + /// Used for simplifying paths to the highlighted source code files. + pub(crate) src_root: PathBuf, + /// This describes the layout of each page, and is not modified after + /// creation of the context (contains info like the favicon and added html). + pub(crate) layout: layout::Layout, + /// The local file sources we've emitted and their respective url-paths. + pub(crate) local_sources: FxHashMap, + /// Show the memory layout of types in the docs. + pub(super) show_type_layout: bool, + /// The base-URL of the issue tracker for when an item has been tagged with + /// an issue number. + pub(super) issue_tracker_base_url: Option, + /// The directories that have already been created in this doc run. Used to reduce the number + /// of spurious `create_dir_all` calls. + created_dirs: RefCell>, + /// This flag indicates whether listings of modules (in the side bar and documentation itself) + /// should be ordered alphabetically or in order of appearance (in the source code). + pub(super) module_sorting: ModuleSorting, + /// Additional CSS files to be added to the generated docs. + pub(crate) style_files: Vec, + /// Suffix to be added on resource files (if suffix is "-v2" then "light.css" becomes + /// "light-v2.css"). + pub(crate) resource_suffix: String, + /// Optional path string to be used to load static files on output pages. If not set, uses + /// combinations of `../` to reach the documentation root. + pub(crate) static_root_path: Option, + /// The fs handle we are working with. + pub(crate) fs: DocFS, + pub(super) codes: ErrorCodes, + pub(super) playground: Option, + all: RefCell, + /// Storage for the errors produced while generating documentation so they + /// can be printed together at the end. + errors: Receiver, + /// `None` by default, depends on the `generate-redirect-map` option flag. If this field is set + /// to `Some(...)`, it'll store redirections and then generate a JSON file at the top level of + /// the crate. + redirections: Option>>, + + /// Correspondance map used to link types used in the source code pages to allow to click on + /// links to jump to the type's definition. + pub(crate) span_correspondance_map: FxHashMap, + /// The [`Cache`] used during rendering. + pub(crate) cache: Cache, + + pub(crate) call_locations: AllCallLocations, +} + +impl SharedContext<'_> { + pub(crate) fn ensure_dir(&self, dst: &Path) -> Result<(), Error> { + let mut dirs = self.created_dirs.borrow_mut(); + if !dirs.contains(dst) { + try_err!(self.fs.create_dir_all(dst), dst); + dirs.insert(dst.to_path_buf()); + } + + Ok(()) + } + + pub(crate) fn edition(&self) -> Edition { + self.tcx.sess.edition() + } +} + +impl<'tcx> Context<'tcx> { + pub(crate) fn tcx(&self) -> TyCtxt<'tcx> { + self.shared.tcx + } + + pub(crate) fn cache(&self) -> &Cache { + &self.shared.cache + } + + pub(super) fn sess(&self) -> &'tcx Session { + self.shared.tcx.sess + } + + pub(super) fn derive_id(&mut self, id: String) -> String { + self.id_map.derive(id) + } + + /// String representation of how to get back to the root path of the 'doc/' + /// folder in terms of a relative URL. + pub(super) fn root_path(&self) -> String { + "../".repeat(self.current.len()) + } + + fn render_item(&mut self, it: &clean::Item, is_module: bool) -> String { + let mut title = String::new(); + if !is_module { + title.push_str(it.name.unwrap().as_str()); + } + if !it.is_primitive() && !it.is_keyword() { + if !is_module { + title.push_str(" in "); + } + // No need to include the namespace for primitive types and keywords + title.push_str(&join_with_double_colon(&self.current)); + }; + title.push_str(" - Rust"); + let tyname = it.type_(); + let desc = it.doc_value().as_ref().map(|doc| plain_text_summary(doc)); + let desc = if let Some(desc) = desc { + desc + } else if it.is_crate() { + format!("API documentation for the Rust `{}` crate.", self.shared.layout.krate) + } else { + format!( + "API documentation for the Rust `{}` {} in crate `{}`.", + it.name.as_ref().unwrap(), + tyname, + self.shared.layout.krate + ) + }; + let keywords = make_item_keywords(it); + let name; + let tyname_s = if it.is_crate() { + name = format!("{} crate", tyname); + name.as_str() + } else { + tyname.as_str() + }; + + if !self.render_redirect_pages { + let clone_shared = Rc::clone(&self.shared); + let page = layout::Page { + css_class: tyname_s, + root_path: &self.root_path(), + static_root_path: clone_shared.static_root_path.as_deref(), + title: &title, + description: &desc, + keywords: &keywords, + resource_suffix: &clone_shared.resource_suffix, + }; + let mut page_buffer = Buffer::html(); + print_item(self, it, &mut page_buffer, &page); + layout::render( + &clone_shared.layout, + &page, + |buf: &mut _| print_sidebar(self, it, buf), + move |buf: &mut Buffer| buf.push_buffer(page_buffer), + &clone_shared.style_files, + ) + } else { + if let Some(&(ref names, ty)) = self.cache().paths.get(&it.item_id.expect_def_id()) { + if self.current.len() + 1 != names.len() + || self.current.iter().zip(names.iter()).any(|(a, b)| a != b) + { + // We checked that the redirection isn't pointing to the current file, + // preventing an infinite redirection loop in the generated + // documentation. + + let mut path = String::new(); + for name in &names[..names.len() - 1] { + path.push_str(name.as_str()); + path.push('/'); + } + path.push_str(&item_path(ty, names.last().unwrap().as_str())); + match self.shared.redirections { + Some(ref redirections) => { + let mut current_path = String::new(); + for name in &self.current { + current_path.push_str(name.as_str()); + current_path.push('/'); + } + current_path.push_str(&item_path(ty, names.last().unwrap().as_str())); + redirections.borrow_mut().insert(current_path, path); + } + None => return layout::redirect(&format!("{}{}", self.root_path(), path)), + } + } + } + String::new() + } + } + + /// Construct a map of items shown in the sidebar to a plain-text summary of their docs. + fn build_sidebar_items(&self, m: &clean::Module) -> BTreeMap> { + // BTreeMap instead of HashMap to get a sorted output + let mut map: BTreeMap<_, Vec<_>> = BTreeMap::new(); + let mut inserted: FxHashMap> = FxHashMap::default(); + + for item in &m.items { + if item.is_stripped() { + continue; + } + + let short = item.type_(); + let myname = match item.name { + None => continue, + Some(s) => s, + }; + if inserted.entry(short).or_default().insert(myname) { + let short = short.to_string(); + let myname = myname.to_string(); + map.entry(short).or_default().push(( + myname, + Some(item.doc_value().map_or_else(String::new, |s| plain_text_summary(&s))), + )); + } + } + + match self.shared.module_sorting { + ModuleSorting::Alphabetical => { + for items in map.values_mut() { + items.sort(); + } + } + ModuleSorting::DeclarationOrder => {} + } + map + } + + /// Generates a url appropriate for an `href` attribute back to the source of + /// this item. + /// + /// The url generated, when clicked, will redirect the browser back to the + /// original source code. + /// + /// If `None` is returned, then a source link couldn't be generated. This + /// may happen, for example, with externally inlined items where the source + /// of their crate documentation isn't known. + pub(super) fn src_href(&self, item: &clean::Item) -> Option { + self.href_from_span(item.span(self.tcx()), true) + } + + pub(crate) fn href_from_span(&self, span: clean::Span, with_lines: bool) -> Option { + if span.is_dummy() { + return None; + } + let mut root = self.root_path(); + let mut path = String::new(); + let cnum = span.cnum(self.sess()); + + // We can safely ignore synthetic `SourceFile`s. + let file = match span.filename(self.sess()) { + FileName::Real(ref path) => path.local_path_if_available().to_path_buf(), + _ => return None, + }; + let file = &file; + + let krate_sym; + let (krate, path) = if cnum == LOCAL_CRATE { + if let Some(path) = self.shared.local_sources.get(file) { + (self.shared.layout.krate.as_str(), path) + } else { + return None; + } + } else { + let (krate, src_root) = match *self.cache().extern_locations.get(&cnum)? { + ExternalLocation::Local => { + let e = ExternalCrate { crate_num: cnum }; + (e.name(self.tcx()), e.src_root(self.tcx())) + } + ExternalLocation::Remote(ref s) => { + root = s.to_string(); + let e = ExternalCrate { crate_num: cnum }; + (e.name(self.tcx()), e.src_root(self.tcx())) + } + ExternalLocation::Unknown => return None, + }; + + sources::clean_path(&src_root, file, false, |component| { + path.push_str(&component.to_string_lossy()); + path.push('/'); + }); + let mut fname = file.file_name().expect("source has no filename").to_os_string(); + fname.push(".html"); + path.push_str(&fname.to_string_lossy()); + krate_sym = krate; + (krate_sym.as_str(), &path) + }; + + let anchor = if with_lines { + let loline = span.lo(self.sess()).line; + let hiline = span.hi(self.sess()).line; + format!( + "#{}", + if loline == hiline { + loline.to_string() + } else { + format!("{}-{}", loline, hiline) + } + ) + } else { + "".to_string() + }; + Some(format!( + "{root}src/{krate}/{path}{anchor}", + root = Escape(&root), + krate = krate, + path = path, + anchor = anchor + )) + } +} + +/// Generates the documentation for `crate` into the directory `dst` +impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> { + fn descr() -> &'static str { + "html" + } + + const RUN_ON_MODULE: bool = true; + + fn init( + krate: clean::Crate, + options: RenderOptions, + cache: Cache, + tcx: TyCtxt<'tcx>, + ) -> Result<(Self, clean::Crate), Error> { + // need to save a copy of the options for rendering the index page + let md_opts = options.clone(); + let emit_crate = options.should_emit_crate(); + let RenderOptions { + output, + external_html, + id_map, + playground_url, + module_sorting, + themes: style_files, + default_settings, + extension_css, + resource_suffix, + static_root_path, + unstable_features, + generate_redirect_map, + show_type_layout, + generate_link_to_definition, + call_locations, + no_emit_shared, + .. + } = options; + + let src_root = match krate.src(tcx) { + FileName::Real(ref p) => match p.local_path_if_available().parent() { + Some(p) => p.to_path_buf(), + None => PathBuf::new(), + }, + _ => PathBuf::new(), + }; + // If user passed in `--playground-url` arg, we fill in crate name here + let mut playground = None; + if let Some(url) = playground_url { + playground = + Some(markdown::Playground { crate_name: Some(krate.name(tcx).to_string()), url }); + } + let mut layout = layout::Layout { + logo: String::new(), + favicon: String::new(), + external_html, + default_settings, + krate: krate.name(tcx).to_string(), + css_file_extension: extension_css, + scrape_examples_extension: !call_locations.is_empty(), + }; + let mut issue_tracker_base_url = None; + let mut include_sources = true; + + // Crawl the crate attributes looking for attributes which control how we're + // going to emit HTML + for attr in krate.module.attrs.lists(sym::doc) { + match (attr.name_or_empty(), attr.value_str()) { + (sym::html_favicon_url, Some(s)) => { + layout.favicon = s.to_string(); + } + (sym::html_logo_url, Some(s)) => { + layout.logo = s.to_string(); + } + (sym::html_playground_url, Some(s)) => { + playground = Some(markdown::Playground { + crate_name: Some(krate.name(tcx).to_string()), + url: s.to_string(), + }); + } + (sym::issue_tracker_base_url, Some(s)) => { + issue_tracker_base_url = Some(s.to_string()); + } + (sym::html_no_source, None) if attr.is_word() => { + include_sources = false; + } + _ => {} + } + } + + let (local_sources, matches) = collect_spans_and_sources( + tcx, + &krate, + &src_root, + include_sources, + generate_link_to_definition, + ); + + let (sender, receiver) = channel(); + let mut scx = SharedContext { + tcx, + src_root, + local_sources, + issue_tracker_base_url, + layout, + created_dirs: Default::default(), + module_sorting, + style_files, + resource_suffix, + static_root_path, + fs: DocFS::new(sender), + codes: ErrorCodes::from(unstable_features.is_nightly_build()), + playground, + all: RefCell::new(AllTypes::new()), + errors: receiver, + redirections: if generate_redirect_map { Some(Default::default()) } else { None }, + show_type_layout, + span_correspondance_map: matches, + cache, + call_locations, + }; + + // Add the default themes to the `Vec` of stylepaths + // + // Note that these must be added before `sources::render` is called + // so that the resulting source pages are styled + // + // `light.css` is not disabled because it is the stylesheet that stays loaded + // by the browser as the theme stylesheet. The theme system (hackily) works by + // changing the href to this stylesheet. All other themes are disabled to + // prevent rule conflicts + scx.style_files.push(StylePath { path: PathBuf::from("light.css") }); + scx.style_files.push(StylePath { path: PathBuf::from("dark.css") }); + scx.style_files.push(StylePath { path: PathBuf::from("ayu.css") }); + + let dst = output; + scx.ensure_dir(&dst)?; + + let mut cx = Context { + current: Vec::new(), + dst, + render_redirect_pages: false, + id_map, + deref_id_map: FxHashMap::default(), + shared: Rc::new(scx), + include_sources, + }; + + if emit_crate { + sources::render(&mut cx, &krate)?; + } + + if !no_emit_shared { + // Build our search index + let index = build_index(&krate, &mut Rc::get_mut(&mut cx.shared).unwrap().cache, tcx); + + // Write shared runs within a flock; disable thread dispatching of IO temporarily. + Rc::get_mut(&mut cx.shared).unwrap().fs.set_sync_only(true); + write_shared(&mut cx, &krate, index, &md_opts)?; + Rc::get_mut(&mut cx.shared).unwrap().fs.set_sync_only(false); + } + + Ok((cx, krate)) + } + + fn make_child_renderer(&self) -> Self { + Self { + current: self.current.clone(), + dst: self.dst.clone(), + render_redirect_pages: self.render_redirect_pages, + deref_id_map: FxHashMap::default(), + id_map: IdMap::new(), + shared: Rc::clone(&self.shared), + include_sources: self.include_sources, + } + } + + fn after_krate(&mut self) -> Result<(), Error> { + let crate_name = self.tcx().crate_name(LOCAL_CRATE); + let final_file = self.dst.join(crate_name.as_str()).join("all.html"); + let settings_file = self.dst.join("settings.html"); + let scrape_examples_help_file = self.dst.join("scrape-examples-help.html"); + + let mut root_path = self.dst.to_str().expect("invalid path").to_owned(); + if !root_path.ends_with('/') { + root_path.push('/'); + } + let shared = Rc::clone(&self.shared); + let mut page = layout::Page { + title: "List of all items in this crate", + css_class: "mod", + root_path: "../", + static_root_path: shared.static_root_path.as_deref(), + description: "List of all items in this crate", + keywords: BASIC_KEYWORDS, + resource_suffix: &shared.resource_suffix, + }; + let sidebar = if shared.cache.crate_version.is_some() { + format!("

Crate {}

", crate_name) + } else { + String::new() + }; + let all = shared.all.replace(AllTypes::new()); + let v = layout::render( + &shared.layout, + &page, + sidebar, + |buf: &mut Buffer| all.print(buf), + &shared.style_files, + ); + shared.fs.write(final_file, v)?; + + // Generating settings page. + page.title = "Rustdoc settings"; + page.description = "Settings of Rustdoc"; + page.root_path = "./"; + + let sidebar = "

Settings

"; + let v = layout::render( + &shared.layout, + &page, + sidebar, + |buf: &mut Buffer| { + write!( + buf, + "
\ +

\ + Rustdoc settings\ +

\ + \ + \ + Back\ + \ + \ +
\ + \ + \ + ", + root_path = page.static_root_path.unwrap_or(""), + suffix = page.resource_suffix, + ) + }, + &shared.style_files, + ); + shared.fs.write(settings_file, v)?; + + if shared.layout.scrape_examples_extension { + page.title = "About scraped examples"; + page.description = "How the scraped examples feature works in Rustdoc"; + let v = layout::render( + &shared.layout, + &page, + "", + scrape_examples_help(&*shared), + &shared.style_files, + ); + shared.fs.write(scrape_examples_help_file, v)?; + } + + if let Some(ref redirections) = shared.redirections { + if !redirections.borrow().is_empty() { + let redirect_map_path = + self.dst.join(crate_name.as_str()).join("redirect-map.json"); + let paths = serde_json::to_string(&*redirections.borrow()).unwrap(); + shared.ensure_dir(&self.dst.join(crate_name.as_str()))?; + shared.fs.write(redirect_map_path, paths)?; + } + } + + // No need for it anymore. + drop(shared); + + // Flush pending errors. + Rc::get_mut(&mut self.shared).unwrap().fs.close(); + let nb_errors = + self.shared.errors.iter().map(|err| self.tcx().sess.struct_err(&err).emit()).count(); + if nb_errors > 0 { + Err(Error::new(io::Error::new(io::ErrorKind::Other, "I/O error"), "")) + } else { + Ok(()) + } + } + + fn mod_item_in(&mut self, item: &clean::Item) -> Result<(), Error> { + // Stripped modules survive the rustdoc passes (i.e., `strip-private`) + // if they contain impls for public types. These modules can also + // contain items such as publicly re-exported structures. + // + // External crates will provide links to these structures, so + // these modules are recursed into, but not rendered normally + // (a flag on the context). + if !self.render_redirect_pages { + self.render_redirect_pages = item.is_stripped(); + } + let item_name = item.name.unwrap(); + self.dst.push(&*item_name.as_str()); + self.current.push(item_name); + + info!("Recursing into {}", self.dst.display()); + + let buf = self.render_item(item, true); + // buf will be empty if the module is stripped and there is no redirect for it + if !buf.is_empty() { + self.shared.ensure_dir(&self.dst)?; + let joint_dst = self.dst.join("index.html"); + self.shared.fs.write(joint_dst, buf)?; + } + + // Render sidebar-items.js used throughout this module. + if !self.render_redirect_pages { + let (clean::StrippedItem(box clean::ModuleItem(ref module)) | clean::ModuleItem(ref module)) = *item.kind + else { unreachable!() }; + let items = self.build_sidebar_items(module); + let js_dst = self.dst.join(&format!("sidebar-items{}.js", self.shared.resource_suffix)); + let v = format!("window.SIDEBAR_ITEMS = {};", serde_json::to_string(&items).unwrap()); + self.shared.fs.write(js_dst, v)?; + } + Ok(()) + } + + fn mod_item_out(&mut self) -> Result<(), Error> { + info!("Recursed; leaving {}", self.dst.display()); + + // Go back to where we were at + self.dst.pop(); + self.current.pop(); + Ok(()) + } + + fn item(&mut self, item: clean::Item) -> Result<(), Error> { + // Stripped modules survive the rustdoc passes (i.e., `strip-private`) + // if they contain impls for public types. These modules can also + // contain items such as publicly re-exported structures. + // + // External crates will provide links to these structures, so + // these modules are recursed into, but not rendered normally + // (a flag on the context). + if !self.render_redirect_pages { + self.render_redirect_pages = item.is_stripped(); + } + + let buf = self.render_item(&item, false); + // buf will be empty if the item is stripped and there is no redirect for it + if !buf.is_empty() { + let name = item.name.as_ref().unwrap(); + let item_type = item.type_(); + let file_name = &item_path(item_type, name.as_str()); + self.shared.ensure_dir(&self.dst)?; + let joint_dst = self.dst.join(file_name); + self.shared.fs.write(joint_dst, buf)?; + + if !self.render_redirect_pages { + self.shared.all.borrow_mut().append(full_path(self, &item), &item_type); + } + // If the item is a macro, redirect from the old macro URL (with !) + // to the new one (without). + if item_type == ItemType::Macro { + let redir_name = format!("{}.{}!.html", item_type, name); + if let Some(ref redirections) = self.shared.redirections { + let crate_name = &self.shared.layout.krate; + redirections.borrow_mut().insert( + format!("{}/{}", crate_name, redir_name), + format!("{}/{}", crate_name, file_name), + ); + } else { + let v = layout::redirect(file_name); + let redir_dst = self.dst.join(redir_name); + self.shared.fs.write(redir_dst, v)?; + } + } + } + Ok(()) + } + + fn cache(&self) -> &Cache { + &self.shared.cache + } +} + +fn make_item_keywords(it: &clean::Item) -> String { + format!("{}, {}", BASIC_KEYWORDS, it.name.as_ref().unwrap()) +} diff --git a/src/librustdoc/html/render/mod.rs b/src/librustdoc/html/render/mod.rs new file mode 100644 index 000000000..a262c8f7d --- /dev/null +++ b/src/librustdoc/html/render/mod.rs @@ -0,0 +1,2849 @@ +//! Rustdoc's HTML rendering module. +//! +//! This modules contains the bulk of the logic necessary for rendering a +//! rustdoc `clean::Crate` instance to a set of static HTML pages. This +//! rendering process is largely driven by the `format!` syntax extension to +//! perform all I/O into files and streams. +//! +//! The rendering process is largely driven by the `Context` and `Cache` +//! structures. The cache is pre-populated by crawling the crate in question, +//! and then it is shared among the various rendering threads. The cache is meant +//! to be a fairly large structure not implementing `Clone` (because it's shared +//! among threads). The context, however, should be a lightweight structure. This +//! is cloned per-thread and contains information about what is currently being +//! rendered. +//! +//! In order to speed up rendering (mostly because of markdown rendering), the +//! rendering process has been parallelized. This parallelization is only +//! exposed through the `crate` method on the context, and then also from the +//! fact that the shared cache is stored in TLS (and must be accessed as such). +//! +//! In addition to rendering the crate itself, this module is also responsible +//! for creating the corresponding search index and source file renderings. +//! These threads are not parallelized (they haven't been a bottleneck yet), and +//! both occur before the crate is rendered. + +pub(crate) mod search_index; + +#[cfg(test)] +mod tests; + +mod context; +mod print_item; +mod span_map; +mod write_shared; + +pub(crate) use self::context::*; +pub(crate) use self::span_map::{collect_spans_and_sources, LinkFromSrc}; + +use std::collections::VecDeque; +use std::default::Default; +use std::fmt; +use std::fs; +use std::iter::Peekable; +use std::path::PathBuf; +use std::rc::Rc; +use std::str; +use std::string::ToString; + +use rustc_ast_pretty::pprust; +use rustc_attr::{ConstStability, Deprecation, StabilityLevel}; +use rustc_data_structures::fx::{FxHashMap, FxHashSet}; +use rustc_hir::def::CtorKind; +use rustc_hir::def_id::DefId; +use rustc_hir::Mutability; +use rustc_middle::middle::stability; +use rustc_middle::ty; +use rustc_middle::ty::TyCtxt; +use rustc_span::{ + symbol::{sym, Symbol}, + BytePos, FileName, RealFileName, +}; +use serde::ser::SerializeSeq; +use serde::{Serialize, Serializer}; + +use crate::clean::{self, ItemId, RenderedLink, SelfTy}; +use crate::error::Error; +use crate::formats::cache::Cache; +use crate::formats::item_type::ItemType; +use crate::formats::{AssocItemRender, Impl, RenderMode}; +use crate::html::escape::Escape; +use crate::html::format::{ + href, join_with_double_colon, print_abi_with_space, print_constness_with_space, + print_default_space, print_generic_bounds, print_where_clause, Buffer, Ending, HrefError, + PrintWithSpace, +}; +use crate::html::highlight; +use crate::html::markdown::{HeadingOffset, IdMap, Markdown, MarkdownHtml, MarkdownSummaryLine}; +use crate::html::sources; +use crate::html::static_files::SCRAPE_EXAMPLES_HELP_MD; +use crate::scrape_examples::{CallData, CallLocation}; +use crate::try_none; +use crate::DOC_RUST_LANG_ORG_CHANNEL; + +/// A pair of name and its optional document. +pub(crate) type NameDoc = (String, Option); + +pub(crate) fn ensure_trailing_slash(v: &str) -> impl fmt::Display + '_ { + crate::html::format::display_fn(move |f| { + if !v.ends_with('/') && !v.is_empty() { write!(f, "{}/", v) } else { f.write_str(v) } + }) +} + +// Helper structs for rendering items/sidebars and carrying along contextual +// information + +/// Struct representing one entry in the JS search index. These are all emitted +/// by hand to a large JS file at the end of cache-creation. +#[derive(Debug)] +pub(crate) struct IndexItem { + pub(crate) ty: ItemType, + pub(crate) name: String, + pub(crate) path: String, + pub(crate) desc: String, + pub(crate) parent: Option, + pub(crate) parent_idx: Option, + pub(crate) search_type: Option, + pub(crate) aliases: Box<[Symbol]>, +} + +/// A type used for the search index. +#[derive(Debug)] +pub(crate) struct RenderType { + id: Option, + generics: Option>, +} + +impl Serialize for RenderType { + fn serialize(&self, serializer: S) -> Result + where + S: Serializer, + { + let id = match &self.id { + // 0 is a sentinel, everything else is one-indexed + None => 0, + Some(RenderTypeId::Index(idx)) => idx + 1, + _ => panic!("must convert render types to indexes before serializing"), + }; + if let Some(generics) = &self.generics { + let mut seq = serializer.serialize_seq(None)?; + seq.serialize_element(&id)?; + seq.serialize_element(generics)?; + seq.end() + } else { + id.serialize(serializer) + } + } +} + +#[derive(Clone, Debug)] +pub(crate) enum RenderTypeId { + DefId(DefId), + Primitive(clean::PrimitiveType), + Index(usize), +} + +/// Full type of functions/methods in the search index. +#[derive(Debug)] +pub(crate) struct IndexItemFunctionType { + inputs: Vec, + output: Vec, +} + +impl Serialize for IndexItemFunctionType { + fn serialize(&self, serializer: S) -> Result + where + S: Serializer, + { + // If we couldn't figure out a type, just write `0`. + let has_missing = self + .inputs + .iter() + .chain(self.output.iter()) + .any(|i| i.id.is_none() && i.generics.is_none()); + if has_missing { + 0.serialize(serializer) + } else { + let mut seq = serializer.serialize_seq(None)?; + match &self.inputs[..] { + [one] if one.generics.is_none() => seq.serialize_element(one)?, + _ => seq.serialize_element(&self.inputs)?, + } + match &self.output[..] { + [] => {} + [one] if one.generics.is_none() => seq.serialize_element(one)?, + _ => seq.serialize_element(&self.output)?, + } + seq.end() + } + } +} + +#[derive(Debug, Clone)] +pub(crate) struct StylePath { + /// The path to the theme + pub(crate) path: PathBuf, +} + +impl StylePath { + pub(crate) fn basename(&self) -> Result { + Ok(try_none!(try_none!(self.path.file_stem(), &self.path).to_str(), &self.path).to_string()) + } +} + +fn write_srclink(cx: &Context<'_>, item: &clean::Item, buf: &mut Buffer) { + if let Some(l) = cx.src_href(item) { + write!(buf, "source", l) + } +} + +#[derive(Debug, Eq, PartialEq, Hash)] +struct ItemEntry { + url: String, + name: String, +} + +impl ItemEntry { + fn new(mut url: String, name: String) -> ItemEntry { + while url.starts_with('/') { + url.remove(0); + } + ItemEntry { url, name } + } +} + +impl ItemEntry { + pub(crate) fn print(&self) -> impl fmt::Display + '_ { + crate::html::format::display_fn(move |f| { + write!(f, "{}", self.url, Escape(&self.name)) + }) + } +} + +impl PartialOrd for ItemEntry { + fn partial_cmp(&self, other: &ItemEntry) -> Option<::std::cmp::Ordering> { + Some(self.cmp(other)) + } +} + +impl Ord for ItemEntry { + fn cmp(&self, other: &ItemEntry) -> ::std::cmp::Ordering { + self.name.cmp(&other.name) + } +} + +#[derive(Debug)] +struct AllTypes { + structs: FxHashSet, + enums: FxHashSet, + unions: FxHashSet, + primitives: FxHashSet, + traits: FxHashSet, + macros: FxHashSet, + functions: FxHashSet, + typedefs: FxHashSet, + opaque_tys: FxHashSet, + statics: FxHashSet, + constants: FxHashSet, + attributes: FxHashSet, + derives: FxHashSet, + trait_aliases: FxHashSet, +} + +impl AllTypes { + fn new() -> AllTypes { + let new_set = |cap| FxHashSet::with_capacity_and_hasher(cap, Default::default()); + AllTypes { + structs: new_set(100), + enums: new_set(100), + unions: new_set(100), + primitives: new_set(26), + traits: new_set(100), + macros: new_set(100), + functions: new_set(100), + typedefs: new_set(100), + opaque_tys: new_set(100), + statics: new_set(100), + constants: new_set(100), + attributes: new_set(100), + derives: new_set(100), + trait_aliases: new_set(100), + } + } + + fn append(&mut self, item_name: String, item_type: &ItemType) { + let mut url: Vec<_> = item_name.split("::").skip(1).collect(); + if let Some(name) = url.pop() { + let new_url = format!("{}/{}.{}.html", url.join("/"), item_type, name); + url.push(name); + let name = url.join("::"); + match *item_type { + ItemType::Struct => self.structs.insert(ItemEntry::new(new_url, name)), + ItemType::Enum => self.enums.insert(ItemEntry::new(new_url, name)), + ItemType::Union => self.unions.insert(ItemEntry::new(new_url, name)), + ItemType::Primitive => self.primitives.insert(ItemEntry::new(new_url, name)), + ItemType::Trait => self.traits.insert(ItemEntry::new(new_url, name)), + ItemType::Macro => self.macros.insert(ItemEntry::new(new_url, name)), + ItemType::Function => self.functions.insert(ItemEntry::new(new_url, name)), + ItemType::Typedef => self.typedefs.insert(ItemEntry::new(new_url, name)), + ItemType::OpaqueTy => self.opaque_tys.insert(ItemEntry::new(new_url, name)), + ItemType::Static => self.statics.insert(ItemEntry::new(new_url, name)), + ItemType::Constant => self.constants.insert(ItemEntry::new(new_url, name)), + ItemType::ProcAttribute => self.attributes.insert(ItemEntry::new(new_url, name)), + ItemType::ProcDerive => self.derives.insert(ItemEntry::new(new_url, name)), + ItemType::TraitAlias => self.trait_aliases.insert(ItemEntry::new(new_url, name)), + _ => true, + }; + } + } +} + +impl AllTypes { + fn print(self, f: &mut Buffer) { + fn print_entries(f: &mut Buffer, e: &FxHashSet, title: &str, class: &str) { + if !e.is_empty() { + let mut e: Vec<&ItemEntry> = e.iter().collect(); + e.sort(); + write!( + f, + "

{}

    ", + title.replace(' ', "-"), // IDs cannot contain whitespaces. + title, + class + ); + + for s in e.iter() { + write!(f, "
  • {}
    • ", s.print()); + } + + f.write_str("
"); + } + } + + f.write_str( + "

\ + List of all items\ +

", + ); + // Note: print_entries does not escape the title, because we know the current set of titles + // doesn't require escaping. + print_entries(f, &self.structs, "Structs", "structs"); + print_entries(f, &self.enums, "Enums", "enums"); + print_entries(f, &self.unions, "Unions", "unions"); + print_entries(f, &self.primitives, "Primitives", "primitives"); + print_entries(f, &self.traits, "Traits", "traits"); + print_entries(f, &self.macros, "Macros", "macros"); + print_entries(f, &self.attributes, "Attribute Macros", "attributes"); + print_entries(f, &self.derives, "Derive Macros", "derives"); + print_entries(f, &self.functions, "Functions", "functions"); + print_entries(f, &self.typedefs, "Typedefs", "typedefs"); + print_entries(f, &self.trait_aliases, "Trait Aliases", "trait-aliases"); + print_entries(f, &self.opaque_tys, "Opaque Types", "opaque-types"); + print_entries(f, &self.statics, "Statics", "statics"); + print_entries(f, &self.constants, "Constants", "constants") + } +} + +fn scrape_examples_help(shared: &SharedContext<'_>) -> String { + let mut content = SCRAPE_EXAMPLES_HELP_MD.to_owned(); + content.push_str(&format!( + "## More information\n\n\ + If you want more information about this feature, please read the [corresponding chapter in the Rustdoc book]({}/rustdoc/scraped-examples.html).", + DOC_RUST_LANG_ORG_CHANNEL)); + + let mut ids = IdMap::default(); + format!( + "
\ +

\ + About scraped examples\ +

\ +
\ +
{}
", + Markdown { + content: &content, + links: &[], + ids: &mut ids, + error_codes: shared.codes, + edition: shared.edition(), + playground: &shared.playground, + heading_offset: HeadingOffset::H1 + } + .into_string() + ) +} + +fn document( + w: &mut Buffer, + cx: &mut Context<'_>, + item: &clean::Item, + parent: Option<&clean::Item>, + heading_offset: HeadingOffset, +) { + if let Some(ref name) = item.name { + info!("Documenting {}", name); + } + document_item_info(w, cx, item, parent); + if parent.is_none() { + document_full_collapsible(w, item, cx, heading_offset); + } else { + document_full(w, item, cx, heading_offset); + } +} + +/// Render md_text as markdown. +fn render_markdown( + w: &mut Buffer, + cx: &mut Context<'_>, + md_text: &str, + links: Vec, + heading_offset: HeadingOffset, +) { + write!( + w, + "
{}
", + Markdown { + content: md_text, + links: &links, + ids: &mut cx.id_map, + error_codes: cx.shared.codes, + edition: cx.shared.edition(), + playground: &cx.shared.playground, + heading_offset, + } + .into_string() + ) +} + +/// Writes a documentation block containing only the first paragraph of the documentation. If the +/// docs are longer, a "Read more" link is appended to the end. +fn document_short( + w: &mut Buffer, + item: &clean::Item, + cx: &mut Context<'_>, + link: AssocItemLink<'_>, + parent: &clean::Item, + show_def_docs: bool, +) { + document_item_info(w, cx, item, Some(parent)); + if !show_def_docs { + return; + } + if let Some(s) = item.doc_value() { + let mut summary_html = MarkdownSummaryLine(&s, &item.links(cx)).into_string(); + + if s.contains('\n') { + let link = format!(r#" Read more"#, assoc_href_attr(item, link, cx)); + + if let Some(idx) = summary_html.rfind("

") { + summary_html.insert_str(idx, &link); + } else { + summary_html.push_str(&link); + } + } + + write!(w, "
{}
", summary_html,); + } +} + +fn document_full_collapsible( + w: &mut Buffer, + item: &clean::Item, + cx: &mut Context<'_>, + heading_offset: HeadingOffset, +) { + document_full_inner(w, item, cx, true, heading_offset); +} + +fn document_full( + w: &mut Buffer, + item: &clean::Item, + cx: &mut Context<'_>, + heading_offset: HeadingOffset, +) { + document_full_inner(w, item, cx, false, heading_offset); +} + +fn document_full_inner( + w: &mut Buffer, + item: &clean::Item, + cx: &mut Context<'_>, + is_collapsible: bool, + heading_offset: HeadingOffset, +) { + if let Some(s) = item.collapsed_doc_value() { + debug!("Doc block: =====\n{}\n=====", s); + if is_collapsible { + w.write_str( + "
\ + \ + Expand description\ + ", + ); + render_markdown(w, cx, &s, item.links(cx), heading_offset); + w.write_str("
"); + } else { + render_markdown(w, cx, &s, item.links(cx), heading_offset); + } + } + + let kind = match &*item.kind { + clean::ItemKind::StrippedItem(box kind) | kind => kind, + }; + + if let clean::ItemKind::FunctionItem(..) | clean::ItemKind::MethodItem(..) = kind { + render_call_locations(w, cx, item); + } +} + +/// Add extra information about an item such as: +/// +/// * Stability +/// * Deprecated +/// * Required features (through the `doc_cfg` feature) +fn document_item_info( + w: &mut Buffer, + cx: &mut Context<'_>, + item: &clean::Item, + parent: Option<&clean::Item>, +) { + let item_infos = short_item_info(item, cx, parent); + if !item_infos.is_empty() { + w.write_str(""); + for info in item_infos { + w.write_str(&info); + } + w.write_str(""); + } +} + +fn portability(item: &clean::Item, parent: Option<&clean::Item>) -> Option { + let cfg = match (&item.cfg, parent.and_then(|p| p.cfg.as_ref())) { + (Some(cfg), Some(parent_cfg)) => cfg.simplify_with(parent_cfg), + (cfg, _) => cfg.as_deref().cloned(), + }; + + debug!("Portability {:?} - {:?} = {:?}", item.cfg, parent.and_then(|p| p.cfg.as_ref()), cfg); + + Some(format!("
{}
", cfg?.render_long_html())) +} + +/// Render the stability, deprecation and portability information that is displayed at the top of +/// the item's documentation. +fn short_item_info( + item: &clean::Item, + cx: &mut Context<'_>, + parent: Option<&clean::Item>, +) -> Vec { + let mut extra_info = vec![]; + let error_codes = cx.shared.codes; + + if let Some(depr @ Deprecation { note, since, is_since_rustc_version: _, suggestion: _ }) = + item.deprecation(cx.tcx()) + { + // We display deprecation messages for #[deprecated], but only display + // the future-deprecation messages for rustc versions. + let mut message = if let Some(since) = since { + let since = since.as_str(); + if !stability::deprecation_in_effect(&depr) { + if since == "TBD" { + String::from("Deprecating in a future Rust version") + } else { + format!("Deprecating in {}", Escape(since)) + } + } else { + format!("Deprecated since {}", Escape(since)) + } + } else { + String::from("Deprecated") + }; + + if let Some(note) = note { + let note = note.as_str(); + let html = MarkdownHtml( + note, + &mut cx.id_map, + error_codes, + cx.shared.edition(), + &cx.shared.playground, + ); + message.push_str(&format!(": {}", html.into_string())); + } + extra_info.push(format!( + "
👎 {}
", + message, + )); + } + + // Render unstable items. But don't render "rustc_private" crates (internal compiler crates). + // Those crates are permanently unstable so it makes no sense to render "unstable" everywhere. + if let Some((StabilityLevel::Unstable { reason: _, issue, .. }, feature)) = item + .stability(cx.tcx()) + .as_ref() + .filter(|stab| stab.feature != sym::rustc_private) + .map(|stab| (stab.level, stab.feature)) + { + let mut message = + "🔬 This is a nightly-only experimental API.".to_owned(); + + let mut feature = format!("{}", Escape(feature.as_str())); + if let (Some(url), Some(issue)) = (&cx.shared.issue_tracker_base_url, issue) { + feature.push_str(&format!( + " #{issue}", + url = url, + issue = issue + )); + } + + message.push_str(&format!(" ({})", feature)); + + extra_info.push(format!("
{}
", message)); + } + + if let Some(portability) = portability(item, parent) { + extra_info.push(portability); + } + + extra_info +} + +// Render the list of items inside one of the sections "Trait Implementations", +// "Auto Trait Implementations," "Blanket Trait Implementations" (on struct/enum pages). +fn render_impls( + cx: &mut Context<'_>, + w: &mut Buffer, + impls: &[&&Impl], + containing_item: &clean::Item, + toggle_open_by_default: bool, +) { + let tcx = cx.tcx(); + let mut rendered_impls = impls + .iter() + .map(|i| { + let did = i.trait_did().unwrap(); + let provided_trait_methods = i.inner_impl().provided_trait_methods(tcx); + let assoc_link = AssocItemLink::GotoSource(did.into(), &provided_trait_methods); + let mut buffer = if w.is_for_html() { Buffer::html() } else { Buffer::new() }; + render_impl( + &mut buffer, + cx, + i, + containing_item, + assoc_link, + RenderMode::Normal, + None, + &[], + ImplRenderingParameters { + show_def_docs: true, + show_default_items: true, + show_non_assoc_items: true, + toggle_open_by_default, + }, + ); + buffer.into_inner() + }) + .collect::>(); + rendered_impls.sort(); + w.write_str(&rendered_impls.join("")); +} + +/// Build a (possibly empty) `href` attribute (a key-value pair) for the given associated item. +fn assoc_href_attr(it: &clean::Item, link: AssocItemLink<'_>, cx: &Context<'_>) -> String { + let name = it.name.unwrap(); + let item_type = it.type_(); + + let href = match link { + AssocItemLink::Anchor(Some(ref id)) => Some(format!("#{}", id)), + AssocItemLink::Anchor(None) => Some(format!("#{}.{}", item_type, name)), + AssocItemLink::GotoSource(did, provided_methods) => { + // We're creating a link from the implementation of an associated item to its + // declaration in the trait declaration. + let item_type = match item_type { + // For historical but not technical reasons, the item type of methods in + // trait declarations depends on whether the method is required (`TyMethod`) or + // provided (`Method`). + ItemType::Method | ItemType::TyMethod => { + if provided_methods.contains(&name) { + ItemType::Method + } else { + ItemType::TyMethod + } + } + // For associated types and constants, no such distinction exists. + item_type => item_type, + }; + + match href(did.expect_def_id(), cx) { + Ok((url, ..)) => Some(format!("{}#{}.{}", url, item_type, name)), + // The link is broken since it points to an external crate that wasn't documented. + // Do not create any link in such case. This is better than falling back to a + // dummy anchor like `#{item_type}.{name}` representing the `id` of *this* impl item + // (that used to happen in older versions). Indeed, in most cases this dummy would + // coincide with the `id`. However, it would not always do so. + // In general, this dummy would be incorrect: + // If the type with the trait impl also had an inherent impl with an assoc. item of + // the *same* name as this impl item, the dummy would link to that one even though + // those two items are distinct! + // In this scenario, the actual `id` of this impl item would be + // `#{item_type}.{name}-{n}` for some number `n` (a disambiguator). + Err(HrefError::DocumentationNotBuilt) => None, + Err(_) => Some(format!("#{}.{}", item_type, name)), + } + } + }; + + // If there is no `href` for the reason explained above, simply do not render it which is valid: + // https://html.spec.whatwg.org/multipage/links.html#links-created-by-a-and-area-elements + href.map(|href| format!(" href=\"{}\"", href)).unwrap_or_default() +} + +fn assoc_const( + w: &mut Buffer, + it: &clean::Item, + ty: &clean::Type, + default: Option<&clean::ConstantKind>, + link: AssocItemLink<'_>, + extra: &str, + cx: &Context<'_>, +) { + write!( + w, + "{extra}{vis}const {name}: {ty}", + extra = extra, + vis = it.visibility.print_with_space(it.item_id, cx), + href = assoc_href_attr(it, link, cx), + name = it.name.as_ref().unwrap(), + ty = ty.print(cx), + ); + if let Some(default) = default { + write!(w, " = "); + + // FIXME: `.value()` uses `clean::utils::format_integer_with_underscore_sep` under the + // hood which adds noisy underscores and a type suffix to number literals. + // This hurts readability in this context especially when more complex expressions + // are involved and it doesn't add much of value. + // Find a way to print constants here without all that jazz. + write!(w, "{}", Escape(&default.value(cx.tcx()).unwrap_or_else(|| default.expr(cx.tcx())))); + } +} + +fn assoc_type( + w: &mut Buffer, + it: &clean::Item, + generics: &clean::Generics, + bounds: &[clean::GenericBound], + default: Option<&clean::Type>, + link: AssocItemLink<'_>, + indent: usize, + cx: &Context<'_>, +) { + write!( + w, + "{indent}type {name}{generics}", + indent = " ".repeat(indent), + href = assoc_href_attr(it, link, cx), + name = it.name.as_ref().unwrap(), + generics = generics.print(cx), + ); + if !bounds.is_empty() { + write!(w, ": {}", print_generic_bounds(bounds, cx)) + } + write!(w, "{}", print_where_clause(generics, cx, indent, Ending::NoNewline)); + if let Some(default) = default { + write!(w, " = {}", default.print(cx)) + } +} + +fn assoc_method( + w: &mut Buffer, + meth: &clean::Item, + g: &clean::Generics, + d: &clean::FnDecl, + link: AssocItemLink<'_>, + parent: ItemType, + cx: &Context<'_>, + render_mode: RenderMode, +) { + let header = meth.fn_header(cx.tcx()).expect("Trying to get header from a non-function item"); + let name = meth.name.as_ref().unwrap(); + let vis = meth.visibility.print_with_space(meth.item_id, cx).to_string(); + // FIXME: Once https://github.com/rust-lang/rust/issues/67792 is implemented, we can remove + // this condition. + let constness = match render_mode { + RenderMode::Normal => { + print_constness_with_space(&header.constness, meth.const_stability(cx.tcx())) + } + RenderMode::ForDeref { .. } => "", + }; + let asyncness = header.asyncness.print_with_space(); + let unsafety = header.unsafety.print_with_space(); + let defaultness = print_default_space(meth.is_default()); + let abi = print_abi_with_space(header.abi).to_string(); + let href = assoc_href_attr(meth, link, cx); + + // NOTE: `{:#}` does not print HTML formatting, `{}` does. So `g.print` can't be reused between the length calculation and `write!`. + let generics_len = format!("{:#}", g.print(cx)).len(); + let mut header_len = "fn ".len() + + vis.len() + + constness.len() + + asyncness.len() + + unsafety.len() + + defaultness.len() + + abi.len() + + name.as_str().len() + + generics_len; + + let (indent, indent_str, end_newline) = if parent == ItemType::Trait { + header_len += 4; + let indent_str = " "; + render_attributes_in_pre(w, meth, indent_str); + (4, indent_str, Ending::NoNewline) + } else { + render_attributes_in_code(w, meth); + (0, "", Ending::Newline) + }; + w.reserve(header_len + "{".len() + "".len()); + write!( + w, + "{indent}{vis}{constness}{asyncness}{unsafety}{defaultness}{abi}fn {name}\ + {generics}{decl}{notable_traits}{where_clause}", + indent = indent_str, + vis = vis, + constness = constness, + asyncness = asyncness, + unsafety = unsafety, + defaultness = defaultness, + abi = abi, + href = href, + name = name, + generics = g.print(cx), + decl = d.full_print(header_len, indent, header.asyncness, cx), + notable_traits = notable_traits_decl(d, cx), + where_clause = print_where_clause(g, cx, indent, end_newline), + ) +} + +/// Writes a span containing the versions at which an item became stable and/or const-stable. For +/// example, if the item became stable at 1.0.0, and const-stable at 1.45.0, this function would +/// write a span containing "1.0.0 (const: 1.45.0)". +/// +/// Returns `true` if a stability annotation was rendered. +/// +/// Stability and const-stability are considered separately. If the item is unstable, no version +/// will be written. If the item is const-unstable, "const: unstable" will be appended to the +/// span, with a link to the tracking issue if present. If an item's stability or const-stability +/// version matches the version of its enclosing item, that version will be omitted. +/// +/// Note that it is possible for an unstable function to be const-stable. In that case, the span +/// will include the const-stable version, but no stable version will be emitted, as a natural +/// consequence of the above rules. +fn render_stability_since_raw( + w: &mut Buffer, + ver: Option, + const_stability: Option, + containing_ver: Option, + containing_const_ver: Option, +) -> bool { + let stable_version = ver.filter(|inner| !inner.is_empty() && Some(*inner) != containing_ver); + + let mut title = String::new(); + let mut stability = String::new(); + + if let Some(ver) = stable_version { + stability.push_str(ver.as_str()); + title.push_str(&format!("Stable since Rust version {}", ver)); + } + + let const_title_and_stability = match const_stability { + Some(ConstStability { level: StabilityLevel::Stable { since, .. }, .. }) + if Some(since) != containing_const_ver => + { + Some((format!("const since {}", since), format!("const: {}", since))) + } + Some(ConstStability { level: StabilityLevel::Unstable { issue, .. }, feature, .. }) => { + let unstable = if let Some(n) = issue { + format!( + r#"unstable"#, + n, feature + ) + } else { + String::from("unstable") + }; + + Some((String::from("const unstable"), format!("const: {}", unstable))) + } + _ => None, + }; + + if let Some((const_title, const_stability)) = const_title_and_stability { + if !title.is_empty() { + title.push_str(&format!(", {}", const_title)); + } else { + title.push_str(&const_title); + } + + if !stability.is_empty() { + stability.push_str(&format!(" ({})", const_stability)); + } else { + stability.push_str(&const_stability); + } + } + + if !stability.is_empty() { + write!(w, r#"{}"#, title, stability); + } + + !stability.is_empty() +} + +fn render_assoc_item( + w: &mut Buffer, + item: &clean::Item, + link: AssocItemLink<'_>, + parent: ItemType, + cx: &Context<'_>, + render_mode: RenderMode, +) { + match &*item.kind { + clean::StrippedItem(..) => {} + clean::TyMethodItem(m) => { + assoc_method(w, item, &m.generics, &m.decl, link, parent, cx, render_mode) + } + clean::MethodItem(m, _) => { + assoc_method(w, item, &m.generics, &m.decl, link, parent, cx, render_mode) + } + kind @ (clean::TyAssocConstItem(ty) | clean::AssocConstItem(ty, _)) => assoc_const( + w, + item, + ty, + match kind { + clean::TyAssocConstItem(_) => None, + clean::AssocConstItem(_, default) => Some(default), + _ => unreachable!(), + }, + link, + if parent == ItemType::Trait { " " } else { "" }, + cx, + ), + clean::TyAssocTypeItem(ref generics, ref bounds) => assoc_type( + w, + item, + generics, + bounds, + None, + link, + if parent == ItemType::Trait { 4 } else { 0 }, + cx, + ), + clean::AssocTypeItem(ref ty, ref bounds) => assoc_type( + w, + item, + &ty.generics, + bounds, + Some(ty.item_type.as_ref().unwrap_or(&ty.type_)), + link, + if parent == ItemType::Trait { 4 } else { 0 }, + cx, + ), + _ => panic!("render_assoc_item called on non-associated-item"), + } +} + +const ALLOWED_ATTRIBUTES: &[Symbol] = + &[sym::export_name, sym::link_section, sym::no_mangle, sym::repr, sym::non_exhaustive]; + +fn attributes(it: &clean::Item) -> Vec { + it.attrs + .other_attrs + .iter() + .filter_map(|attr| { + if ALLOWED_ATTRIBUTES.contains(&attr.name_or_empty()) { + Some( + pprust::attribute_to_string(attr) + .replace("\\\n", "") + .replace('\n', "") + .replace(" ", " "), + ) + } else { + None + } + }) + .collect() +} + +// When an attribute is rendered inside a `
` tag, it is formatted using
+// a whitespace prefix and newline.
+fn render_attributes_in_pre(w: &mut Buffer, it: &clean::Item, prefix: &str) {
+    for a in attributes(it) {
+        writeln!(w, "{}{}", prefix, a);
+    }
+}
+
+// When an attribute is rendered inside a  tag, it is formatted using
+// a div to produce a newline after it.
+fn render_attributes_in_code(w: &mut Buffer, it: &clean::Item) {
+    for a in attributes(it) {
+        write!(w, "
{}
", a);
+    }
+}
+
+#[derive(Copy, Clone)]
+enum AssocItemLink<'a> {
+    Anchor(Option<&'a str>),
+    GotoSource(ItemId, &'a FxHashSet),
+}
+
+impl<'a> AssocItemLink<'a> {
+    fn anchor(&self, id: &'a str) -> Self {
+        match *self {
+            AssocItemLink::Anchor(_) => AssocItemLink::Anchor(Some(id)),
+            ref other => *other,
+        }
+    }
+}
+
+fn render_assoc_items(
+    w: &mut Buffer,
+    cx: &mut Context<'_>,
+    containing_item: &clean::Item,
+    it: DefId,
+    what: AssocItemRender<'_>,
+) {
+    let mut derefs = FxHashSet::default();
+    derefs.insert(it);
+    render_assoc_items_inner(w, cx, containing_item, it, what, &mut derefs)
+}
+
+fn render_assoc_items_inner(
+    w: &mut Buffer,
+    cx: &mut Context<'_>,
+    containing_item: &clean::Item,
+    it: DefId,
+    what: AssocItemRender<'_>,
+    derefs: &mut FxHashSet,
+) {
+    info!("Documenting associated items of {:?}", containing_item.name);
+    let shared = Rc::clone(&cx.shared);
+    let cache = &shared.cache;
+    let Some(v) = cache.impls.get(&it) else { return };
+    let (non_trait, traits): (Vec<_>, _) = v.iter().partition(|i| i.inner_impl().trait_.is_none());
+    if !non_trait.is_empty() {
+        let mut tmp_buf = Buffer::empty_from(w);
+        let (render_mode, id) = match what {
+            AssocItemRender::All => {
+                tmp_buf.write_str(
+                    "
\
+                         Implementations\
+                         \
+                     
",
+                );
+                (RenderMode::Normal, "implementations-list".to_owned())
+            }
+            AssocItemRender::DerefFor { trait_, type_, deref_mut_ } => {
+                let id =
+                    cx.derive_id(small_url_encode(format!("deref-methods-{:#}", type_.print(cx))));
+                if let Some(def_id) = type_.def_id(cx.cache()) {
+                    cx.deref_id_map.insert(def_id, id.clone());
+                }
+                write!(
+                    tmp_buf,
+                    "
\
+                         Methods from {trait_}<Target = {type_}>\
+                         \
+                     
",
+                    id = id,
+                    trait_ = trait_.print(cx),
+                    type_ = type_.print(cx),
+                );
+                (RenderMode::ForDeref { mut_: deref_mut_ }, cx.derive_id(id))
+            }
+        };
+        let mut impls_buf = Buffer::empty_from(w);
+        for i in &non_trait {
+            render_impl(
+                &mut impls_buf,
+                cx,
+                i,
+                containing_item,
+                AssocItemLink::Anchor(None),
+                render_mode,
+                None,
+                &[],
+                ImplRenderingParameters {
+                    show_def_docs: true,
+                    show_default_items: true,
+                    show_non_assoc_items: true,
+                    toggle_open_by_default: true,
+                },
+            );
+        }
+        if !impls_buf.is_empty() {
+            w.push_buffer(tmp_buf);
+            write!(w, "
", id);
+            w.push_buffer(impls_buf);
+            w.write_str("
");
+        }
+    }
+
+    if !traits.is_empty() {
+        let deref_impl =
+            traits.iter().find(|t| t.trait_did() == cx.tcx().lang_items().deref_trait());
+        if let Some(impl_) = deref_impl {
+            let has_deref_mut =
+                traits.iter().any(|t| t.trait_did() == cx.tcx().lang_items().deref_mut_trait());
+            render_deref_methods(w, cx, impl_, containing_item, has_deref_mut, derefs);
+        }
+
+        // If we were already one level into rendering deref methods, we don't want to render
+        // anything after recursing into any further deref methods above.
+        if let AssocItemRender::DerefFor { .. } = what {
+            return;
+        }
+
+        let (synthetic, concrete): (Vec<&&Impl>, Vec<&&Impl>) =
+            traits.iter().partition(|t| t.inner_impl().kind.is_auto());
+        let (blanket_impl, concrete): (Vec<&&Impl>, _) =
+            concrete.into_iter().partition(|t| t.inner_impl().kind.is_blanket());
+
+        let mut impls = Buffer::empty_from(w);
+        render_impls(cx, &mut impls, &concrete, containing_item, true);
+        let impls = impls.into_inner();
+        if !impls.is_empty() {
+            write!(
+                w,
+                "
\
+                     Trait Implementations\
+                     \
+                 
\
+                 
{}
",
+                impls
+            );
+        }
+
+        if !synthetic.is_empty() {
+            w.write_str(
+                "
\
+                     Auto Trait Implementations\
+                     \
+                 
\
+                 
",
+            );
+            render_impls(cx, w, &synthetic, containing_item, false);
+            w.write_str("
");
+        }
+
+        if !blanket_impl.is_empty() {
+            w.write_str(
+                "
\
+                     Blanket Implementations\
+                     \
+                 
\
+                 
",
+            );
+            render_impls(cx, w, &blanket_impl, containing_item, false);
+            w.write_str("
");
+        }
+    }
+}
+
+fn render_deref_methods(
+    w: &mut Buffer,
+    cx: &mut Context<'_>,
+    impl_: &Impl,
+    container_item: &clean::Item,
+    deref_mut: bool,
+    derefs: &mut FxHashSet,
+) {
+    let cache = cx.cache();
+    let deref_type = impl_.inner_impl().trait_.as_ref().unwrap();
+    let (target, real_target) = impl_
+        .inner_impl()
+        .items
+        .iter()
+        .find_map(|item| match *item.kind {
+            clean::AssocTypeItem(box ref t, _) => Some(match *t {
+                clean::Typedef { item_type: Some(ref type_), .. } => (type_, &t.type_),
+                _ => (&t.type_, &t.type_),
+            }),
+            _ => None,
+        })
+        .expect("Expected associated type binding");
+    debug!("Render deref methods for {:#?}, target {:#?}", impl_.inner_impl().for_, target);
+    let what =
+        AssocItemRender::DerefFor { trait_: deref_type, type_: real_target, deref_mut_: deref_mut };
+    if let Some(did) = target.def_id(cache) {
+        if let Some(type_did) = impl_.inner_impl().for_.def_id(cache) {
+            // `impl Deref for S`
+            if did == type_did || !derefs.insert(did) {
+                // Avoid infinite cycles
+                return;
+            }
+        }
+        render_assoc_items_inner(w, cx, container_item, did, what, derefs);
+    } else if let Some(prim) = target.primitive_type() {
+        if let Some(&did) = cache.primitive_locations.get(&prim) {
+            render_assoc_items_inner(w, cx, container_item, did, what, derefs);
+        }
+    }
+}
+
+fn should_render_item(item: &clean::Item, deref_mut_: bool, tcx: TyCtxt<'_>) -> bool {
+    let self_type_opt = match *item.kind {
+        clean::MethodItem(ref method, _) => method.decl.self_type(),
+        clean::TyMethodItem(ref method) => method.decl.self_type(),
+        _ => None,
+    };
+
+    if let Some(self_ty) = self_type_opt {
+        let (by_mut_ref, by_box, by_value) = match self_ty {
+            SelfTy::SelfBorrowed(_, mutability)
+            | SelfTy::SelfExplicit(clean::BorrowedRef { mutability, .. }) => {
+                (mutability == Mutability::Mut, false, false)
+            }
+            SelfTy::SelfExplicit(clean::Type::Path { path }) => {
+                (false, Some(path.def_id()) == tcx.lang_items().owned_box(), false)
+            }
+            SelfTy::SelfValue => (false, false, true),
+            _ => (false, false, false),
+        };
+
+        (deref_mut_ || !by_mut_ref) && !by_box && !by_value
+    } else {
+        false
+    }
+}
+
+fn notable_traits_decl(decl: &clean::FnDecl, cx: &Context<'_>) -> String {
+    let mut out = Buffer::html();
+
+    if let Some((did, ty)) = decl.output.as_return().and_then(|t| Some((t.def_id(cx.cache())?, t)))
+    {
+        if let Some(impls) = cx.cache().impls.get(&did) {
+            for i in impls {
+                let impl_ = i.inner_impl();
+                if !impl_.for_.without_borrowed_ref().is_same(ty.without_borrowed_ref(), cx.cache())
+                {
+                    // Two different types might have the same did,
+                    // without actually being the same.
+                    continue;
+                }
+                if let Some(trait_) = &impl_.trait_ {
+                    let trait_did = trait_.def_id();
+
+                    if cx.cache().traits.get(&trait_did).map_or(false, |t| t.is_notable) {
+                        if out.is_empty() {
+                            write!(
+                                &mut out,
+                                "Notable traits for {}\
+                             ",
+                                impl_.for_.print(cx)
+                            );
+                        }
+
+                        //use the "where" class here to make it small
+                        write!(
+                            &mut out,
+                            "{}",
+                            impl_.print(false, cx)
+                        );
+                        for it in &impl_.items {
+                            if let clean::AssocTypeItem(ref tydef, ref _bounds) = *it.kind {
+                                out.push_str("    ");
+                                let empty_set = FxHashSet::default();
+                                let src_link =
+                                    AssocItemLink::GotoSource(trait_did.into(), &empty_set);
+                                assoc_type(
+                                    &mut out,
+                                    it,
+                                    &tydef.generics,
+                                    &[], // intentionally leaving out bounds
+                                    Some(&tydef.type_),
+                                    src_link,
+                                    0,
+                                    cx,
+                                );
+                                out.push_str(";");
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    if !out.is_empty() {
+        out.insert_str(
+            0,
+            "ⓘ\
+            ",
+        );
+        out.push_str("");
+    }
+
+    out.into_inner()
+}
+
+#[derive(Clone, Copy, Debug)]
+struct ImplRenderingParameters {
+    show_def_docs: bool,
+    show_default_items: bool,
+    /// Whether or not to show methods.
+    show_non_assoc_items: bool,
+    toggle_open_by_default: bool,
+}
+
+fn render_impl(
+    w: &mut Buffer,
+    cx: &mut Context<'_>,
+    i: &Impl,
+    parent: &clean::Item,
+    link: AssocItemLink<'_>,
+    render_mode: RenderMode,
+    use_absolute: Option,
+    aliases: &[String],
+    rendering_params: ImplRenderingParameters,
+) {
+    let shared = Rc::clone(&cx.shared);
+    let cache = &shared.cache;
+    let traits = &cache.traits;
+    let trait_ = i.trait_did().map(|did| &traits[&did]);
+    let mut close_tags = String::new();
+
+    // For trait implementations, the `interesting` output contains all methods that have doc
+    // comments, and the `boring` output contains all methods that do not. The distinction is
+    // used to allow hiding the boring methods.
+    // `containing_item` is used for rendering stability info. If the parent is a trait impl,
+    // `containing_item` will the grandparent, since trait impls can't have stability attached.
+    fn doc_impl_item(
+        boring: &mut Buffer,
+        interesting: &mut Buffer,
+        cx: &mut Context<'_>,
+        item: &clean::Item,
+        parent: &clean::Item,
+        containing_item: &clean::Item,
+        link: AssocItemLink<'_>,
+        render_mode: RenderMode,
+        is_default_item: bool,
+        trait_: Option<&clean::Trait>,
+        rendering_params: ImplRenderingParameters,
+    ) {
+        let item_type = item.type_();
+        let name = item.name.as_ref().unwrap();
+
+        let render_method_item = rendering_params.show_non_assoc_items
+            && match render_mode {
+                RenderMode::Normal => true,
+                RenderMode::ForDeref { mut_: deref_mut_ } => {
+                    should_render_item(item, deref_mut_, cx.tcx())
+                }
+            };
+
+        let in_trait_class = if trait_.is_some() { " trait-impl" } else { "" };
+
+        let mut doc_buffer = Buffer::empty_from(boring);
+        let mut info_buffer = Buffer::empty_from(boring);
+        let mut short_documented = true;
+
+        if render_method_item {
+            if !is_default_item {
+                if let Some(t) = trait_ {
+                    // The trait item may have been stripped so we might not
+                    // find any documentation or stability for it.
+                    if let Some(it) = t.items.iter().find(|i| i.name == item.name) {
+                        // We need the stability of the item from the trait
+                        // because impls can't have a stability.
+                        if item.doc_value().is_some() {
+                            document_item_info(&mut info_buffer, cx, it, Some(parent));
+                            document_full(&mut doc_buffer, item, cx, HeadingOffset::H5);
+                            short_documented = false;
+                        } else {
+                            // In case the item isn't documented,
+                            // provide short documentation from the trait.
+                            document_short(
+                                &mut doc_buffer,
+                                it,
+                                cx,
+                                link,
+                                parent,
+                                rendering_params.show_def_docs,
+                            );
+                        }
+                    }
+                } else {
+                    document_item_info(&mut info_buffer, cx, item, Some(parent));
+                    if rendering_params.show_def_docs {
+                        document_full(&mut doc_buffer, item, cx, HeadingOffset::H5);
+                        short_documented = false;
+                    }
+                }
+            } else {
+                document_short(
+                    &mut doc_buffer,
+                    item,
+                    cx,
+                    link,
+                    parent,
+                    rendering_params.show_def_docs,
+                );
+            }
+        }
+        let w = if short_documented && trait_.is_some() { interesting } else { boring };
+
+        let toggled = !doc_buffer.is_empty();
+        if toggled {
+            let method_toggle_class =
+                if item_type == ItemType::Method { " method-toggle" } else { "" };
+            write!(w, "
", method_toggle_class);
+        }
+        match &*item.kind {
+            clean::MethodItem(..) | clean::TyMethodItem(_) => {
+                // Only render when the method is not static or we allow static methods
+                if render_method_item {
+                    let id = cx.derive_id(format!("{}.{}", item_type, name));
+                    let source_id = trait_
+                        .and_then(|trait_| {
+                            trait_.items.iter().find(|item| {
+                                item.name.map(|n| n.as_str().eq(name.as_str())).unwrap_or(false)
+                            })
+                        })
+                        .map(|item| format!("{}.{}", item.type_(), name));
+                    write!(
+                        w,
+                        "
",
+                        id, item_type, in_trait_class,
+                    );
+                    render_rightside(w, cx, item, containing_item, render_mode);
+                    if trait_.is_some() {
+                        // Anchors are only used on trait impls.
+                        write!(w, "", id);
+                    }
+                    w.write_str("
");
+                    render_assoc_item(
+                        w,
+                        item,
+                        link.anchor(source_id.as_ref().unwrap_or(&id)),
+                        ItemType::Impl,
+                        cx,
+                        render_mode,
+                    );
+                    w.write_str("
");
+                    w.write_str("
");
+                }
+            }
+            kind @ (clean::TyAssocConstItem(ty) | clean::AssocConstItem(ty, _)) => {
+                let source_id = format!("{}.{}", item_type, name);
+                let id = cx.derive_id(source_id.clone());
+                write!(
+                    w,
+                    "
",
+                    id, item_type, in_trait_class
+                );
+                render_rightside(w, cx, item, containing_item, render_mode);
+                if trait_.is_some() {
+                    // Anchors are only used on trait impls.
+                    write!(w, "", id);
+                }
+                w.write_str("
");
+                assoc_const(
+                    w,
+                    item,
+                    ty,
+                    match kind {
+                        clean::TyAssocConstItem(_) => None,
+                        clean::AssocConstItem(_, default) => Some(default),
+                        _ => unreachable!(),
+                    },
+                    link.anchor(if trait_.is_some() { &source_id } else { &id }),
+                    "",
+                    cx,
+                );
+                w.write_str("
");
+                w.write_str("
");
+            }
+            clean::TyAssocTypeItem(generics, bounds) => {
+                let source_id = format!("{}.{}", item_type, name);
+                let id = cx.derive_id(source_id.clone());
+                write!(w, "
", id, item_type, in_trait_class);
+                if trait_.is_some() {
+                    // Anchors are only used on trait impls.
+                    write!(w, "", id);
+                }
+                w.write_str("
");
+                assoc_type(
+                    w,
+                    item,
+                    generics,
+                    bounds,
+                    None,
+                    link.anchor(if trait_.is_some() { &source_id } else { &id }),
+                    0,
+                    cx,
+                );
+                w.write_str("
");
+                w.write_str("
");
+            }
+            clean::AssocTypeItem(tydef, _bounds) => {
+                let source_id = format!("{}.{}", item_type, name);
+                let id = cx.derive_id(source_id.clone());
+                write!(
+                    w,
+                    "
",
+                    id, item_type, in_trait_class
+                );
+                if trait_.is_some() {
+                    // Anchors are only used on trait impls.
+                    write!(w, "", id);
+                }
+                w.write_str("
");
+                assoc_type(
+                    w,
+                    item,
+                    &tydef.generics,
+                    &[], // intentionally leaving out bounds
+                    Some(tydef.item_type.as_ref().unwrap_or(&tydef.type_)),
+                    link.anchor(if trait_.is_some() { &source_id } else { &id }),
+                    0,
+                    cx,
+                );
+                w.write_str("
");
+                w.write_str("
");
+            }
+            clean::StrippedItem(..) => return,
+            _ => panic!("can't make docs for trait item with name {:?}", item.name),
+        }
+
+        w.push_buffer(info_buffer);
+        if toggled {
+            w.write_str("");
+            w.push_buffer(doc_buffer);
+            w.push_str("
");
+        }
+    }
+
+    let mut impl_items = Buffer::empty_from(w);
+    let mut default_impl_items = Buffer::empty_from(w);
+
+    for trait_item in &i.inner_impl().items {
+        doc_impl_item(
+            &mut default_impl_items,
+            &mut impl_items,
+            cx,
+            trait_item,
+            if trait_.is_some() { &i.impl_item } else { parent },
+            parent,
+            link,
+            render_mode,
+            false,
+            trait_.map(|t| &t.trait_),
+            rendering_params,
+        );
+    }
+
+    fn render_default_items(
+        boring: &mut Buffer,
+        interesting: &mut Buffer,
+        cx: &mut Context<'_>,
+        t: &clean::Trait,
+        i: &clean::Impl,
+        parent: &clean::Item,
+        containing_item: &clean::Item,
+        render_mode: RenderMode,
+        rendering_params: ImplRenderingParameters,
+    ) {
+        for trait_item in &t.items {
+            let n = trait_item.name;
+            if i.items.iter().any(|m| m.name == n) {
+                continue;
+            }
+            let did = i.trait_.as_ref().unwrap().def_id();
+            let provided_methods = i.provided_trait_methods(cx.tcx());
+            let assoc_link = AssocItemLink::GotoSource(did.into(), &provided_methods);
+
+            doc_impl_item(
+                boring,
+                interesting,
+                cx,
+                trait_item,
+                parent,
+                containing_item,
+                assoc_link,
+                render_mode,
+                true,
+                Some(t),
+                rendering_params,
+            );
+        }
+    }
+
+    // If we've implemented a trait, then also emit documentation for all
+    // default items which weren't overridden in the implementation block.
+    // We don't emit documentation for default items if they appear in the
+    // Implementations on Foreign Types or Implementors sections.
+    if rendering_params.show_default_items {
+        if let Some(t) = trait_ {
+            render_default_items(
+                &mut default_impl_items,
+                &mut impl_items,
+                cx,
+                &t.trait_,
+                i.inner_impl(),
+                &i.impl_item,
+                parent,
+                render_mode,
+                rendering_params,
+            );
+        }
+    }
+    if render_mode == RenderMode::Normal {
+        let toggled = !(impl_items.is_empty() && default_impl_items.is_empty());
+        if toggled {
+            close_tags.insert_str(0, "");
+            write!(
+                w,
+                "
",
+                if rendering_params.toggle_open_by_default { " open" } else { "" }
+            );
+            write!(w, "")
+        }
+        render_impl_summary(
+            w,
+            cx,
+            i,
+            parent,
+            parent,
+            rendering_params.show_def_docs,
+            use_absolute,
+            aliases,
+        );
+        if toggled {
+            write!(w, "")
+        }
+
+        if let Some(ref dox) = i.impl_item.collapsed_doc_value() {
+            if trait_.is_none() && i.inner_impl().items.is_empty() {
+                w.write_str(
+                    "
\
+                    
This impl block contains no items.

+                
",
+                );
+            }
+            write!(
+                w,
+                "
{}
",
+                Markdown {
+                    content: &*dox,
+                    links: &i.impl_item.links(cx),
+                    ids: &mut cx.id_map,
+                    error_codes: cx.shared.codes,
+                    edition: cx.shared.edition(),
+                    playground: &cx.shared.playground,
+                    heading_offset: HeadingOffset::H4
+                }
+                .into_string()
+            );
+        }
+    }
+    if !default_impl_items.is_empty() || !impl_items.is_empty() {
+        w.write_str("
");
+        w.push_buffer(default_impl_items);
+        w.push_buffer(impl_items);
+        close_tags.insert_str(0, "
");
+    }
+    w.write_str(&close_tags);
+}
+
+// Render the items that appear on the right side of methods, impls, and
+// associated types. For example "1.0.0 (const: 1.39.0) · source".
+fn render_rightside(
+    w: &mut Buffer,
+    cx: &Context<'_>,
+    item: &clean::Item,
+    containing_item: &clean::Item,
+    render_mode: RenderMode,
+) {
+    let tcx = cx.tcx();
+
+    // FIXME: Once https://github.com/rust-lang/rust/issues/67792 is implemented, we can remove
+    // this condition.
+    let (const_stability, const_stable_since) = match render_mode {
+        RenderMode::Normal => (item.const_stability(tcx), containing_item.const_stable_since(tcx)),
+        RenderMode::ForDeref { .. } => (None, None),
+    };
+
+    let mut rightside = Buffer::new();
+    let has_stability = render_stability_since_raw(
+        &mut rightside,
+        item.stable_since(tcx),
+        const_stability,
+        containing_item.stable_since(tcx),
+        const_stable_since,
+    );
+    let mut srclink = Buffer::empty_from(w);
+    write_srclink(cx, item, &mut srclink);
+    if has_stability && !srclink.is_empty() {
+        rightside.write_str(" · ");
+    }
+    rightside.push_buffer(srclink);
+    if !rightside.is_empty() {
+        write!(w, "{}", rightside.into_inner());
+    }
+}
+
+pub(crate) fn render_impl_summary(
+    w: &mut Buffer,
+    cx: &mut Context<'_>,
+    i: &Impl,
+    parent: &clean::Item,
+    containing_item: &clean::Item,
+    show_def_docs: bool,
+    use_absolute: Option,
+    // This argument is used to reference same type with different paths to avoid duplication
+    // in documentation pages for trait with automatic implementations like "Send" and "Sync".
+    aliases: &[String],
+) {
+    let id =
+        cx.derive_id(get_id_for_impl(&i.inner_impl().for_, i.inner_impl().trait_.as_ref(), cx));
+    let aliases = if aliases.is_empty() {
+        String::new()
+    } else {
+        format!(" data-aliases=\"{}\"", aliases.join(","))
+    };
+    write!(w, "
", id, aliases);
+    render_rightside(w, cx, &i.impl_item, containing_item, RenderMode::Normal);
+    write!(w, "", id);
+    write!(w, "
");
+
+    if let Some(use_absolute) = use_absolute {
+        write!(w, "{}", i.inner_impl().print(use_absolute, cx));
+        if show_def_docs {
+            for it in &i.inner_impl().items {
+                if let clean::AssocTypeItem(ref tydef, ref _bounds) = *it.kind {
+                    w.write_str("  ");
+                    assoc_type(
+                        w,
+                        it,
+                        &tydef.generics,
+                        &[], // intentionally leaving out bounds
+                        Some(&tydef.type_),
+                        AssocItemLink::Anchor(None),
+                        0,
+                        cx,
+                    );
+                    w.write_str(";");
+                }
+            }
+        }
+    } else {
+        write!(w, "{}", i.inner_impl().print(false, cx));
+    }
+    write!(w, "
");
+
+    let is_trait = i.inner_impl().trait_.is_some();
+    if is_trait {
+        if let Some(portability) = portability(&i.impl_item, Some(parent)) {
+            write!(w, "{}", portability);
+        }
+    }
+
+    w.write_str("
");
+}
+
+fn print_sidebar(cx: &Context<'_>, it: &clean::Item, buffer: &mut Buffer) {
+    if it.is_struct()
+        || it.is_trait()
+        || it.is_primitive()
+        || it.is_union()
+        || it.is_enum()
+        || it.is_mod()
+        || it.is_typedef()
+    {
+        write!(
+            buffer,
+            "
{}{}
",
+            match *it.kind {
+                clean::ModuleItem(..) =>
+                    if it.is_crate() {
+                        "Crate "
+                    } else {
+                        "Module "
+                    },
+                _ => "",
+            },
+            it.name.as_ref().unwrap()
+        );
+    }
+
+    buffer.write_str("
");
+    if it.is_crate() {
+        write!(buffer, "
    ");
+        if let Some(ref version) = cx.cache().crate_version {
+            write!(buffer, "
  • Version {}
    • ", Escape(version));
+        }
+        write!(buffer, "
  • All Items
    • ");
+        buffer.write_str("
");
+    }
+
+    match *it.kind {
+        clean::StructItem(ref s) => sidebar_struct(cx, buffer, it, s),
+        clean::TraitItem(ref t) => sidebar_trait(cx, buffer, it, t),
+        clean::PrimitiveItem(_) => sidebar_primitive(cx, buffer, it),
+        clean::UnionItem(ref u) => sidebar_union(cx, buffer, it, u),
+        clean::EnumItem(ref e) => sidebar_enum(cx, buffer, it, e),
+        clean::TypedefItem(_) => sidebar_typedef(cx, buffer, it),
+        clean::ModuleItem(ref m) => sidebar_module(buffer, &m.items),
+        clean::ForeignTypeItem => sidebar_foreign_type(cx, buffer, it),
+        _ => {}
+    }
+
+    // The sidebar is designed to display sibling functions, modules and
+    // other miscellaneous information. since there are lots of sibling
+    // items (and that causes quadratic growth in large modules),
+    // we refactor common parts into a shared JavaScript file per module.
+    // still, we don't move everything into JS because we want to preserve
+    // as much HTML as possible in order to allow non-JS-enabled browsers
+    // to navigate the documentation (though slightly inefficiently).
+
+    if !it.is_mod() {
+        let path: String = cx.current.iter().map(|s| s.as_str()).intersperse("::").collect();
+
+        write!(buffer, "
In {}
", path);
+    }
+
+    // Closes sidebar-elems div.
+    buffer.write_str("
");
+}
+
+fn get_next_url(used_links: &mut FxHashSet, url: String) -> String {
+    if used_links.insert(url.clone()) {
+        return url;
+    }
+    let mut add = 1;
+    while !used_links.insert(format!("{}-{}", url, add)) {
+        add += 1;
+    }
+    format!("{}-{}", url, add)
+}
+
+struct SidebarLink {
+    name: Symbol,
+    url: String,
+}
+
+impl fmt::Display for SidebarLink {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", self.url, self.name)
+    }
+}
+
+impl PartialEq for SidebarLink {
+    fn eq(&self, other: &Self) -> bool {
+        self.url == other.url
+    }
+}
+
+impl Eq for SidebarLink {}
+
+impl PartialOrd for SidebarLink {
+    fn partial_cmp(&self, other: &Self) -> Option {
+        Some(self.cmp(other))
+    }
+}
+
+impl Ord for SidebarLink {
+    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
+        self.url.cmp(&other.url)
+    }
+}
+
+fn get_methods(
+    i: &clean::Impl,
+    for_deref: bool,
+    used_links: &mut FxHashSet,
+    deref_mut: bool,
+    tcx: TyCtxt<'_>,
+) -> Vec {
+    i.items
+        .iter()
+        .filter_map(|item| match item.name {
+            Some(name) if !name.is_empty() && item.is_method() => {
+                if !for_deref || should_render_item(item, deref_mut, tcx) {
+                    Some(SidebarLink {
+                        name,
+                        url: get_next_url(used_links, format!("{}.{}", ItemType::Method, name)),
+                    })
+                } else {
+                    None
+                }
+            }
+            _ => None,
+        })
+        .collect::>()
+}
+
+fn get_associated_constants(
+    i: &clean::Impl,
+    used_links: &mut FxHashSet,
+) -> Vec {
+    i.items
+        .iter()
+        .filter_map(|item| match item.name {
+            Some(name) if !name.is_empty() && item.is_associated_const() => Some(SidebarLink {
+                name,
+                url: get_next_url(used_links, format!("{}.{}", ItemType::AssocConst, name)),
+            }),
+            _ => None,
+        })
+        .collect::>()
+}
+
+// The point is to url encode any potential character from a type with genericity.
+fn small_url_encode(s: String) -> String {
+    let mut st = String::new();
+    let mut last_match = 0;
+    for (idx, c) in s.char_indices() {
+        let escaped = match c {
+            '<' => "%3C",
+            '>' => "%3E",
+            ' ' => "%20",
+            '?' => "%3F",
+            '\'' => "%27",
+            '&' => "%26",
+            ',' => "%2C",
+            ':' => "%3A",
+            ';' => "%3B",
+            '[' => "%5B",
+            ']' => "%5D",
+            '"' => "%22",
+            _ => continue,
+        };
+
+        st += &s[last_match..idx];
+        st += escaped;
+        // NOTE: we only expect single byte characters here - which is fine as long as we
+        // only match single byte characters
+        last_match = idx + 1;
+    }
+
+    if last_match != 0 {
+        st += &s[last_match..];
+        st
+    } else {
+        s
+    }
+}
+
+fn sidebar_assoc_items(cx: &Context<'_>, out: &mut Buffer, it: &clean::Item) {
+    let did = it.item_id.expect_def_id();
+    let cache = cx.cache();
+
+    if let Some(v) = cache.impls.get(&did) {
+        let mut used_links = FxHashSet::default();
+        let mut id_map = IdMap::new();
+
+        {
+            let used_links_bor = &mut used_links;
+            let mut assoc_consts = v
+                .iter()
+                .filter(|i| i.inner_impl().trait_.is_none())
+                .flat_map(|i| get_associated_constants(i.inner_impl(), used_links_bor))
+                .collect::>();
+            if !assoc_consts.is_empty() {
+                // We want links' order to be reproducible so we don't use unstable sort.
+                assoc_consts.sort();
+
+                print_sidebar_block(
+                    out,
+                    "implementations",
+                    "Associated Constants",
+                    assoc_consts.iter(),
+                );
+            }
+            let mut methods = v
+                .iter()
+                .filter(|i| i.inner_impl().trait_.is_none())
+                .flat_map(|i| get_methods(i.inner_impl(), false, used_links_bor, false, cx.tcx()))
+                .collect::>();
+            if !methods.is_empty() {
+                // We want links' order to be reproducible so we don't use unstable sort.
+                methods.sort();
+
+                print_sidebar_block(out, "implementations", "Methods", methods.iter());
+            }
+        }
+
+        if v.iter().any(|i| i.inner_impl().trait_.is_some()) {
+            if let Some(impl_) =
+                v.iter().find(|i| i.trait_did() == cx.tcx().lang_items().deref_trait())
+            {
+                let mut derefs = FxHashSet::default();
+                derefs.insert(did);
+                sidebar_deref_methods(cx, out, impl_, v, &mut derefs);
+            }
+
+            let format_impls = |impls: Vec<&Impl>, id_map: &mut IdMap| {
+                let mut links = FxHashSet::default();
+
+                let mut ret = impls
+                    .iter()
+                    .filter_map(|it| {
+                        let trait_ = it.inner_impl().trait_.as_ref()?;
+                        let encoded =
+                            id_map.derive(get_id_for_impl(&it.inner_impl().for_, Some(trait_), cx));
+
+                        let i_display = format!("{:#}", trait_.print(cx));
+                        let out = Escape(&i_display);
+                        let prefix = match it.inner_impl().polarity {
+                            ty::ImplPolarity::Positive | ty::ImplPolarity::Reservation => "",
+                            ty::ImplPolarity::Negative => "!",
+                        };
+                        let generated = format!("{}{}", encoded, prefix, out);
+                        if links.insert(generated.clone()) { Some(generated) } else { None }
+                    })
+                    .collect::>();
+                ret.sort();
+                ret
+            };
+
+            let (synthetic, concrete): (Vec<&Impl>, Vec<&Impl>) =
+                v.iter().partition::, _>(|i| i.inner_impl().kind.is_auto());
+            let (blanket_impl, concrete): (Vec<&Impl>, Vec<&Impl>) =
+                concrete.into_iter().partition::, _>(|i| i.inner_impl().kind.is_blanket());
+
+            let concrete_format = format_impls(concrete, &mut id_map);
+            let synthetic_format = format_impls(synthetic, &mut id_map);
+            let blanket_format = format_impls(blanket_impl, &mut id_map);
+
+            if !concrete_format.is_empty() {
+                print_sidebar_block(
+                    out,
+                    "trait-implementations",
+                    "Trait Implementations",
+                    concrete_format.iter(),
+                );
+            }
+
+            if !synthetic_format.is_empty() {
+                print_sidebar_block(
+                    out,
+                    "synthetic-implementations",
+                    "Auto Trait Implementations",
+                    synthetic_format.iter(),
+                );
+            }
+
+            if !blanket_format.is_empty() {
+                print_sidebar_block(
+                    out,
+                    "blanket-implementations",
+                    "Blanket Implementations",
+                    blanket_format.iter(),
+                );
+            }
+        }
+    }
+}
+
+fn sidebar_deref_methods(
+    cx: &Context<'_>,
+    out: &mut Buffer,
+    impl_: &Impl,
+    v: &[Impl],
+    derefs: &mut FxHashSet,
+) {
+    let c = cx.cache();
+
+    debug!("found Deref: {:?}", impl_);
+    if let Some((target, real_target)) =
+        impl_.inner_impl().items.iter().find_map(|item| match *item.kind {
+            clean::AssocTypeItem(box ref t, _) => Some(match *t {
+                clean::Typedef { item_type: Some(ref type_), .. } => (type_, &t.type_),
+                _ => (&t.type_, &t.type_),
+            }),
+            _ => None,
+        })
+    {
+        debug!("found target, real_target: {:?} {:?}", target, real_target);
+        if let Some(did) = target.def_id(c) {
+            if let Some(type_did) = impl_.inner_impl().for_.def_id(c) {
+                // `impl Deref for S`
+                if did == type_did || !derefs.insert(did) {
+                    // Avoid infinite cycles
+                    return;
+                }
+            }
+        }
+        let deref_mut = v.iter().any(|i| i.trait_did() == cx.tcx().lang_items().deref_mut_trait());
+        let inner_impl = target
+            .def_id(c)
+            .or_else(|| {
+                target.primitive_type().and_then(|prim| c.primitive_locations.get(&prim).cloned())
+            })
+            .and_then(|did| c.impls.get(&did));
+        if let Some(impls) = inner_impl {
+            debug!("found inner_impl: {:?}", impls);
+            let mut used_links = FxHashSet::default();
+            let mut ret = impls
+                .iter()
+                .filter(|i| i.inner_impl().trait_.is_none())
+                .flat_map(|i| {
+                    get_methods(i.inner_impl(), true, &mut used_links, deref_mut, cx.tcx())
+                })
+                .collect::>();
+            if !ret.is_empty() {
+                let id = if let Some(target_def_id) = real_target.def_id(c) {
+                    cx.deref_id_map.get(&target_def_id).expect("Deref section without derived id")
+                } else {
+                    "deref-methods"
+                };
+                let title = format!(
+                    "Methods from {}<Target={}>",
+                    Escape(&format!("{:#}", impl_.inner_impl().trait_.as_ref().unwrap().print(cx))),
+                    Escape(&format!("{:#}", real_target.print(cx))),
+                );
+                // We want links' order to be reproducible so we don't use unstable sort.
+                ret.sort();
+                print_sidebar_block(out, id, &title, ret.iter());
+            }
+        }
+
+        // Recurse into any further impls that might exist for `target`
+        if let Some(target_did) = target.def_id(c) {
+            if let Some(target_impls) = c.impls.get(&target_did) {
+                if let Some(target_deref_impl) = target_impls.iter().find(|i| {
+                    i.inner_impl()
+                        .trait_
+                        .as_ref()
+                        .map(|t| Some(t.def_id()) == cx.tcx().lang_items().deref_trait())
+                        .unwrap_or(false)
+                }) {
+                    sidebar_deref_methods(cx, out, target_deref_impl, target_impls, derefs);
+                }
+            }
+        }
+    }
+}
+
+fn sidebar_struct(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item, s: &clean::Struct) {
+    let mut sidebar = Buffer::new();
+    let fields = get_struct_fields_name(&s.fields);
+
+    if !fields.is_empty() {
+        match s.struct_type {
+            CtorKind::Fictive => {
+                print_sidebar_block(&mut sidebar, "fields", "Fields", fields.iter());
+            }
+            CtorKind::Fn => print_sidebar_title(&mut sidebar, "fields", "Tuple Fields"),
+            CtorKind::Const => {}
+        }
+    }
+
+    sidebar_assoc_items(cx, &mut sidebar, it);
+
+    if !sidebar.is_empty() {
+        write!(buf, "
{}
", sidebar.into_inner());
+    }
+}
+
+fn get_id_for_impl(for_: &clean::Type, trait_: Option<&clean::Path>, cx: &Context<'_>) -> String {
+    match trait_ {
+        Some(t) => small_url_encode(format!("impl-{:#}-for-{:#}", t.print(cx), for_.print(cx))),
+        None => small_url_encode(format!("impl-{:#}", for_.print(cx))),
+    }
+}
+
+fn extract_for_impl_name(item: &clean::Item, cx: &Context<'_>) -> Option<(String, String)> {
+    match *item.kind {
+        clean::ItemKind::ImplItem(ref i) => {
+            i.trait_.as_ref().map(|trait_| {
+                // Alternative format produces no URLs,
+                // so this parameter does nothing.
+                (format!("{:#}", i.for_.print(cx)), get_id_for_impl(&i.for_, Some(trait_), cx))
+            })
+        }
+        _ => None,
+    }
+}
+
+/// Don't call this function directly!!! Use `print_sidebar_title` or `print_sidebar_block` instead!
+fn print_sidebar_title_inner(buf: &mut Buffer, id: &str, title: &str) {
+    write!(
+        buf,
+        "
\
+             {}\
+         
",
+        id, title
+    );
+}
+
+fn print_sidebar_title(buf: &mut Buffer, id: &str, title: &str) {
+    buf.push_str("
");
+    print_sidebar_title_inner(buf, id, title);
+    buf.push_str("
");
+}
+
+fn print_sidebar_block(
+    buf: &mut Buffer,
+    id: &str,
+    title: &str,
+    items: impl Iterator,
+) {
+    buf.push_str("
");
+    print_sidebar_title_inner(buf, id, title);
+    buf.push_str("
    ");
+    for item in items {
+        write!(buf, "
  • {}
    • ", item);
+    }
+    buf.push_str("
");
+}
+
+fn sidebar_trait(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item, t: &clean::Trait) {
+    buf.write_str("
");
+
+    fn print_sidebar_section(
+        out: &mut Buffer,
+        items: &[clean::Item],
+        id: &str,
+        title: &str,
+        filter: impl Fn(&clean::Item) -> bool,
+        mapper: impl Fn(&str) -> String,
+    ) {
+        let mut items: Vec<&str> = items
+            .iter()
+            .filter_map(|m| match m.name {
+                Some(ref name) if filter(m) => Some(name.as_str()),
+                _ => None,
+            })
+            .collect::>();
+
+        if !items.is_empty() {
+            items.sort_unstable();
+            print_sidebar_block(out, id, title, items.into_iter().map(mapper));
+        }
+    }
+
+    print_sidebar_section(
+        buf,
+        &t.items,
+        "required-associated-types",
+        "Required Associated Types",
+        |m| m.is_ty_associated_type(),
+        |sym| format!("{0}", sym, ItemType::AssocType),
+    );
+
+    print_sidebar_section(
+        buf,
+        &t.items,
+        "provided-associated-types",
+        "Provided Associated Types",
+        |m| m.is_associated_type(),
+        |sym| format!("{0}", sym, ItemType::AssocType),
+    );
+
+    print_sidebar_section(
+        buf,
+        &t.items,
+        "required-associated-consts",
+        "Required Associated Constants",
+        |m| m.is_ty_associated_const(),
+        |sym| format!("{0}", sym, ItemType::AssocConst),
+    );
+
+    print_sidebar_section(
+        buf,
+        &t.items,
+        "provided-associated-consts",
+        "Provided Associated Constants",
+        |m| m.is_associated_const(),
+        |sym| format!("{0}", sym, ItemType::AssocConst),
+    );
+
+    print_sidebar_section(
+        buf,
+        &t.items,
+        "required-methods",
+        "Required Methods",
+        |m| m.is_ty_method(),
+        |sym| format!("{0}", sym, ItemType::TyMethod),
+    );
+
+    print_sidebar_section(
+        buf,
+        &t.items,
+        "provided-methods",
+        "Provided Methods",
+        |m| m.is_method(),
+        |sym| format!("{0}", sym, ItemType::Method),
+    );
+
+    if let Some(implementors) = cx.cache().implementors.get(&it.item_id.expect_def_id()) {
+        let mut res = implementors
+            .iter()
+            .filter(|i| !i.is_on_local_type(cx))
+            .filter_map(|i| extract_for_impl_name(&i.impl_item, cx))
+            .collect::>();
+
+        if !res.is_empty() {
+            res.sort();
+            print_sidebar_block(
+                buf,
+                "foreign-impls",
+                "Implementations on Foreign Types",
+                res.iter().map(|(name, id)| format!("{}", id, Escape(name))),
+            );
+        }
+    }
+
+    sidebar_assoc_items(cx, buf, it);
+
+    print_sidebar_title(buf, "implementors", "Implementors");
+    if t.is_auto(cx.tcx()) {
+        print_sidebar_title(buf, "synthetic-implementors", "Auto Implementors");
+    }
+
+    buf.push_str("
")
+}
+
+fn sidebar_primitive(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item) {
+    let mut sidebar = Buffer::new();
+    sidebar_assoc_items(cx, &mut sidebar, it);
+
+    if !sidebar.is_empty() {
+        write!(buf, "
{}
", sidebar.into_inner());
+    }
+}
+
+fn sidebar_typedef(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item) {
+    let mut sidebar = Buffer::new();
+    sidebar_assoc_items(cx, &mut sidebar, it);
+
+    if !sidebar.is_empty() {
+        write!(buf, "
{}
", sidebar.into_inner());
+    }
+}
+
+fn get_struct_fields_name(fields: &[clean::Item]) -> Vec {
+    let mut fields = fields
+        .iter()
+        .filter(|f| matches!(*f.kind, clean::StructFieldItem(..)))
+        .filter_map(|f| {
+            f.name.map(|name| format!("{name}", name = name))
+        })
+        .collect::>();
+    fields.sort();
+    fields
+}
+
+fn sidebar_union(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item, u: &clean::Union) {
+    let mut sidebar = Buffer::new();
+    let fields = get_struct_fields_name(&u.fields);
+
+    if !fields.is_empty() {
+        print_sidebar_block(&mut sidebar, "fields", "Fields", fields.iter());
+    }
+
+    sidebar_assoc_items(cx, &mut sidebar, it);
+
+    if !sidebar.is_empty() {
+        write!(buf, "
{}
", sidebar.into_inner());
+    }
+}
+
+fn sidebar_enum(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item, e: &clean::Enum) {
+    let mut sidebar = Buffer::new();
+
+    let mut variants = e
+        .variants()
+        .filter_map(|v| {
+            v.name
+                .as_ref()
+                .map(|name| format!("{name}", name = name))
+        })
+        .collect::>();
+    if !variants.is_empty() {
+        variants.sort_unstable();
+        print_sidebar_block(&mut sidebar, "variants", "Variants", variants.iter());
+    }
+
+    sidebar_assoc_items(cx, &mut sidebar, it);
+
+    if !sidebar.is_empty() {
+        write!(buf, "
{}
", sidebar.into_inner());
+    }
+}
+
+#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
+enum ItemSection {
+    Reexports,
+    PrimitiveTypes,
+    Modules,
+    Macros,
+    Structs,
+    Enums,
+    Constants,
+    Statics,
+    Traits,
+    Functions,
+    TypeDefinitions,
+    Unions,
+    Implementations,
+    TypeMethods,
+    Methods,
+    StructFields,
+    Variants,
+    AssociatedTypes,
+    AssociatedConstants,
+    ForeignTypes,
+    Keywords,
+    OpaqueTypes,
+    AttributeMacros,
+    DeriveMacros,
+    TraitAliases,
+}
+
+impl ItemSection {
+    const ALL: &'static [Self] = {
+        use ItemSection::*;
+        // NOTE: The order here affects the order in the UI.
+        &[
+            Reexports,
+            PrimitiveTypes,
+            Modules,
+            Macros,
+            Structs,
+            Enums,
+            Constants,
+            Statics,
+            Traits,
+            Functions,
+            TypeDefinitions,
+            Unions,
+            Implementations,
+            TypeMethods,
+            Methods,
+            StructFields,
+            Variants,
+            AssociatedTypes,
+            AssociatedConstants,
+            ForeignTypes,
+            Keywords,
+            OpaqueTypes,
+            AttributeMacros,
+            DeriveMacros,
+            TraitAliases,
+        ]
+    };
+
+    fn id(self) -> &'static str {
+        match self {
+            Self::Reexports => "reexports",
+            Self::Modules => "modules",
+            Self::Structs => "structs",
+            Self::Unions => "unions",
+            Self::Enums => "enums",
+            Self::Functions => "functions",
+            Self::TypeDefinitions => "types",
+            Self::Statics => "statics",
+            Self::Constants => "constants",
+            Self::Traits => "traits",
+            Self::Implementations => "impls",
+            Self::TypeMethods => "tymethods",
+            Self::Methods => "methods",
+            Self::StructFields => "fields",
+            Self::Variants => "variants",
+            Self::Macros => "macros",
+            Self::PrimitiveTypes => "primitives",
+            Self::AssociatedTypes => "associated-types",
+            Self::AssociatedConstants => "associated-consts",
+            Self::ForeignTypes => "foreign-types",
+            Self::Keywords => "keywords",
+            Self::OpaqueTypes => "opaque-types",
+            Self::AttributeMacros => "attributes",
+            Self::DeriveMacros => "derives",
+            Self::TraitAliases => "trait-aliases",
+        }
+    }
+
+    fn name(self) -> &'static str {
+        match self {
+            Self::Reexports => "Re-exports",
+            Self::Modules => "Modules",
+            Self::Structs => "Structs",
+            Self::Unions => "Unions",
+            Self::Enums => "Enums",
+            Self::Functions => "Functions",
+            Self::TypeDefinitions => "Type Definitions",
+            Self::Statics => "Statics",
+            Self::Constants => "Constants",
+            Self::Traits => "Traits",
+            Self::Implementations => "Implementations",
+            Self::TypeMethods => "Type Methods",
+            Self::Methods => "Methods",
+            Self::StructFields => "Struct Fields",
+            Self::Variants => "Variants",
+            Self::Macros => "Macros",
+            Self::PrimitiveTypes => "Primitive Types",
+            Self::AssociatedTypes => "Associated Types",
+            Self::AssociatedConstants => "Associated Constants",
+            Self::ForeignTypes => "Foreign Types",
+            Self::Keywords => "Keywords",
+            Self::OpaqueTypes => "Opaque Types",
+            Self::AttributeMacros => "Attribute Macros",
+            Self::DeriveMacros => "Derive Macros",
+            Self::TraitAliases => "Trait Aliases",
+        }
+    }
+}
+
+fn item_ty_to_section(ty: ItemType) -> ItemSection {
+    match ty {
+        ItemType::ExternCrate | ItemType::Import => ItemSection::Reexports,
+        ItemType::Module => ItemSection::Modules,
+        ItemType::Struct => ItemSection::Structs,
+        ItemType::Union => ItemSection::Unions,
+        ItemType::Enum => ItemSection::Enums,
+        ItemType::Function => ItemSection::Functions,
+        ItemType::Typedef => ItemSection::TypeDefinitions,
+        ItemType::Static => ItemSection::Statics,
+        ItemType::Constant => ItemSection::Constants,
+        ItemType::Trait => ItemSection::Traits,
+        ItemType::Impl => ItemSection::Implementations,
+        ItemType::TyMethod => ItemSection::TypeMethods,
+        ItemType::Method => ItemSection::Methods,
+        ItemType::StructField => ItemSection::StructFields,
+        ItemType::Variant => ItemSection::Variants,
+        ItemType::Macro => ItemSection::Macros,
+        ItemType::Primitive => ItemSection::PrimitiveTypes,
+        ItemType::AssocType => ItemSection::AssociatedTypes,
+        ItemType::AssocConst => ItemSection::AssociatedConstants,
+        ItemType::ForeignType => ItemSection::ForeignTypes,
+        ItemType::Keyword => ItemSection::Keywords,
+        ItemType::OpaqueTy => ItemSection::OpaqueTypes,
+        ItemType::ProcAttribute => ItemSection::AttributeMacros,
+        ItemType::ProcDerive => ItemSection::DeriveMacros,
+        ItemType::TraitAlias => ItemSection::TraitAliases,
+    }
+}
+
+fn sidebar_module(buf: &mut Buffer, items: &[clean::Item]) {
+    use std::fmt::Write as _;
+
+    let mut sidebar = String::new();
+
+    let item_sections_in_use: FxHashSet<_> = items
+        .iter()
+        .filter(|it| {
+            !it.is_stripped()
+                && it
+                    .name
+                    .or_else(|| {
+                        if let clean::ImportItem(ref i) = *it.kind &&
+                            let clean::ImportKind::Simple(s) = i.kind { Some(s) } else { None }
+                    })
+                    .is_some()
+        })
+        .map(|it| item_ty_to_section(it.type_()))
+        .collect();
+    for &sec in ItemSection::ALL.iter().filter(|sec| item_sections_in_use.contains(sec)) {
+        let _ = write!(sidebar, "
  • {}
    • ", sec.id(), sec.name());
+    }
+
+    if !sidebar.is_empty() {
+        write!(
+            buf,
+            "
    \
+                 
    \
+                     
      {}
    \
+                 
    \
+             
    ",
+            sidebar
+        );
+    }
+}
+
+fn sidebar_foreign_type(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item) {
+    let mut sidebar = Buffer::new();
+    sidebar_assoc_items(cx, &mut sidebar, it);
+
+    if !sidebar.is_empty() {
+        write!(buf, "
    {}
    ", sidebar.into_inner());
+    }
+}
+
+pub(crate) const BASIC_KEYWORDS: &str = "rust, rustlang, rust-lang";
+
+/// Returns a list of all paths used in the type.
+/// This is used to help deduplicate imported impls
+/// for reexported types. If any of the contained
+/// types are re-exported, we don't use the corresponding
+/// entry from the js file, as inlining will have already
+/// picked up the impl
+fn collect_paths_for_type(first_ty: clean::Type, cache: &Cache) -> Vec {
+    let mut out = Vec::new();
+    let mut visited = FxHashSet::default();
+    let mut work = VecDeque::new();
+
+    let mut process_path = |did: DefId| {
+        let get_extern = || cache.external_paths.get(&did).map(|s| s.0.clone());
+        let fqp = cache.exact_paths.get(&did).cloned().or_else(get_extern);
+
+        if let Some(path) = fqp {
+            out.push(join_with_double_colon(&path));
+        }
+    };
+
+    work.push_back(first_ty);
+
+    while let Some(ty) = work.pop_front() {
+        if !visited.insert(ty.clone()) {
+            continue;
+        }
+
+        match ty {
+            clean::Type::Path { path } => process_path(path.def_id()),
+            clean::Type::Tuple(tys) => {
+                work.extend(tys.into_iter());
+            }
+            clean::Type::Slice(ty) => {
+                work.push_back(*ty);
+            }
+            clean::Type::Array(ty, _) => {
+                work.push_back(*ty);
+            }
+            clean::Type::RawPointer(_, ty) => {
+                work.push_back(*ty);
+            }
+            clean::Type::BorrowedRef { type_, .. } => {
+                work.push_back(*type_);
+            }
+            clean::Type::QPath { self_type, trait_, .. } => {
+                work.push_back(*self_type);
+                process_path(trait_.def_id());
+            }
+            _ => {}
+        }
+    }
+    out
+}
+
+const MAX_FULL_EXAMPLES: usize = 5;
+const NUM_VISIBLE_LINES: usize = 10;
+
+/// Generates the HTML for example call locations generated via the --scrape-examples flag.
+fn render_call_locations(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Item) {
+    let tcx = cx.tcx();
+    let def_id = item.item_id.expect_def_id();
+    let key = tcx.def_path_hash(def_id);
+    let Some(call_locations) = cx.shared.call_locations.get(&key) else { return };
+
+    // Generate a unique ID so users can link to this section for a given method
+    let id = cx.id_map.derive("scraped-examples");
+    write!(
+        w,
+        "
    \
+          \
+          
    \
+             Examples found in repository\
+             ?\
+          
    ",
+        root_path = cx.root_path(),
+        id = id
+    );
+
+    // Create a URL to a particular location in a reverse-dependency's source file
+    let link_to_loc = |call_data: &CallData, loc: &CallLocation| -> (String, String) {
+        let (line_lo, line_hi) = loc.call_expr.line_span;
+        let (anchor, title) = if line_lo == line_hi {
+            ((line_lo + 1).to_string(), format!("line {}", line_lo + 1))
+        } else {
+            (
+                format!("{}-{}", line_lo + 1, line_hi + 1),
+                format!("lines {}-{}", line_lo + 1, line_hi + 1),
+            )
+        };
+        let url = format!("{}{}#{}", cx.root_path(), call_data.url, anchor);
+        (url, title)
+    };
+
+    // Generate the HTML for a single example, being the title and code block
+    let write_example = |w: &mut Buffer, (path, call_data): (&PathBuf, &CallData)| -> bool {
+        let contents = match fs::read_to_string(&path) {
+            Ok(contents) => contents,
+            Err(err) => {
+                let span = item.span(tcx).inner();
+                tcx.sess
+                    .span_err(span, &format!("failed to read file {}: {}", path.display(), err));
+                return false;
+            }
+        };
+
+        // To reduce file sizes, we only want to embed the source code needed to understand the example, not
+        // the entire file. So we find the smallest byte range that covers all items enclosing examples.
+        assert!(!call_data.locations.is_empty());
+        let min_loc =
+            call_data.locations.iter().min_by_key(|loc| loc.enclosing_item.byte_span.0).unwrap();
+        let byte_min = min_loc.enclosing_item.byte_span.0;
+        let line_min = min_loc.enclosing_item.line_span.0;
+        let max_loc =
+            call_data.locations.iter().max_by_key(|loc| loc.enclosing_item.byte_span.1).unwrap();
+        let byte_max = max_loc.enclosing_item.byte_span.1;
+        let line_max = max_loc.enclosing_item.line_span.1;
+
+        // The output code is limited to that byte range.
+        let contents_subset = &contents[(byte_min as usize)..(byte_max as usize)];
+
+        // The call locations need to be updated to reflect that the size of the program has changed.
+        // Specifically, the ranges are all subtracted by `byte_min` since that's the new zero point.
+        let (mut byte_ranges, line_ranges): (Vec<_>, Vec<_>) = call_data
+            .locations
+            .iter()
+            .map(|loc| {
+                let (byte_lo, byte_hi) = loc.call_ident.byte_span;
+                let (line_lo, line_hi) = loc.call_expr.line_span;
+                let byte_range = (byte_lo - byte_min, byte_hi - byte_min);
+
+                let line_range = (line_lo - line_min, line_hi - line_min);
+                let (line_url, line_title) = link_to_loc(call_data, loc);
+
+                (byte_range, (line_range, line_url, line_title))
+            })
+            .unzip();
+
+        let (_, init_url, init_title) = &line_ranges[0];
+        let needs_expansion = line_max - line_min > NUM_VISIBLE_LINES;
+        let locations_encoded = serde_json::to_string(&line_ranges).unwrap();
+
+        write!(
+            w,
+            "
    \
+                
    \
+                   {name} ({title})\
+                
    \
+                
    ",
+            expanded_cls = if needs_expansion { "" } else { "expanded" },
+            name = call_data.display_name,
+            url = init_url,
+            title = init_title,
+            // The locations are encoded as a data attribute, so they can be read
+            // later by the JS for interactions.
+            locations = Escape(&locations_encoded)
+        );
+
+        if line_ranges.len() > 1 {
+            write!(w, r#"≺ ≻"#);
+        }
+
+        if needs_expansion {
+            write!(w, r#"↕"#);
+        }
+
+        // Look for the example file in the source map if it exists, otherwise return a dummy span
+        let file_span = (|| {
+            let source_map = tcx.sess.source_map();
+            let crate_src = tcx.sess.local_crate_source_file.as_ref()?;
+            let abs_crate_src = crate_src.canonicalize().ok()?;
+            let crate_root = abs_crate_src.parent()?.parent()?;
+            let rel_path = path.strip_prefix(crate_root).ok()?;
+            let files = source_map.files();
+            let file = files.iter().find(|file| match &file.name {
+                FileName::Real(RealFileName::LocalPath(other_path)) => rel_path == other_path,
+                _ => false,
+            })?;
+            Some(rustc_span::Span::with_root_ctxt(
+                file.start_pos + BytePos(byte_min),
+                file.start_pos + BytePos(byte_max),
+            ))
+        })()
+        .unwrap_or(rustc_span::DUMMY_SP);
+
+        // The root path is the inverse of Context::current
+        let root_path = vec!["../"; cx.current.len() - 1].join("");
+
+        let mut decoration_info = FxHashMap::default();
+        decoration_info.insert("highlight focus", vec![byte_ranges.remove(0)]);
+        decoration_info.insert("highlight", byte_ranges);
+
+        sources::print_src(
+            w,
+            contents_subset,
+            call_data.edition,
+            file_span,
+            cx,
+            &root_path,
+            Some(highlight::DecorationInfo(decoration_info)),
+            sources::SourceContext::Embedded { offset: line_min },
+        );
+        write!(w, "
    ");
+
+        true
+    };
+
+    // The call locations are output in sequence, so that sequence needs to be determined.
+    // Ideally the most "relevant" examples would be shown first, but there's no general algorithm
+    // for determining relevance. Instead, we prefer the smallest examples being likely the easiest to
+    // understand at a glance.
+    let ordered_locations = {
+        let sort_criterion = |(_, call_data): &(_, &CallData)| {
+            // Use the first location because that's what the user will see initially
+            let (lo, hi) = call_data.locations[0].enclosing_item.byte_span;
+            hi - lo
+        };
+
+        let mut locs = call_locations.iter().collect::>();
+        locs.sort_by_key(sort_criterion);
+        locs
+    };
+
+    let mut it = ordered_locations.into_iter().peekable();
+
+    // An example may fail to write if its source can't be read for some reason, so this method
+    // continues iterating until a write succeeds
+    let write_and_skip_failure = |w: &mut Buffer, it: &mut Peekable<_>| {
+        while let Some(example) = it.next() {
+            if write_example(&mut *w, example) {
+                break;
+            }
+        }
+    };
+
+    // Write just one example that's visible by default in the method's description.
+    write_and_skip_failure(w, &mut it);
+
+    // Then add the remaining examples in a hidden section.
+    if it.peek().is_some() {
+        write!(
+            w,
+            "
    \
+                  \
+                     More examples\
+                  \
+                  
    Hide additional examples
    \
+                  
    \
+                    
    \
+                    
    "
+        );
+
+        // Only generate inline code for MAX_FULL_EXAMPLES number of examples. Otherwise we could
+        // make the page arbitrarily huge!
+        for _ in 0..MAX_FULL_EXAMPLES {
+            write_and_skip_failure(w, &mut it);
+        }
+
+        // For the remaining examples, generate a 
       containing links to the source files.
+        if it.peek().is_some() {
+            write!(w, r#"
      Additional examples can be found in:
        "#);
+            it.for_each(|(_, call_data)| {
+                let (url, _) = link_to_loc(call_data, &call_data.locations[0]);
+                write!(
+                    w,
+                    r#"
      • {name}
        • "#,
+                    url = url,
+                    name = call_data.display_name
+                );
+            });
+            write!(w, "
      ");
+        }
+
+        write!(w, "
    ");
+    }
+
+    write!(w, "
    ");
+}
diff --git a/src/librustdoc/html/render/print_item.rs b/src/librustdoc/html/render/print_item.rs
new file mode 100644
index 000000000..99cf42919
--- /dev/null
+++ b/src/librustdoc/html/render/print_item.rs
@@ -0,0 +1,1974 @@
+use clean::AttributesExt;
+
+use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_hir as hir;
+use rustc_hir::def::CtorKind;
+use rustc_hir::def_id::DefId;
+use rustc_middle::middle::stability;
+use rustc_middle::span_bug;
+use rustc_middle::ty::layout::LayoutError;
+use rustc_middle::ty::{Adt, TyCtxt};
+use rustc_span::hygiene::MacroKind;
+use rustc_span::symbol::{kw, sym, Symbol};
+use rustc_target::abi::{Layout, Primitive, TagEncoding, Variants};
+use std::cmp::Ordering;
+use std::fmt;
+use std::rc::Rc;
+
+use super::{
+    collect_paths_for_type, document, ensure_trailing_slash, item_ty_to_section,
+    notable_traits_decl, render_assoc_item, render_assoc_items, render_attributes_in_code,
+    render_attributes_in_pre, render_impl, render_stability_since_raw, write_srclink,
+    AssocItemLink, Context, ImplRenderingParameters,
+};
+use crate::clean;
+use crate::config::ModuleSorting;
+use crate::formats::item_type::ItemType;
+use crate::formats::{AssocItemRender, Impl, RenderMode};
+use crate::html::escape::Escape;
+use crate::html::format::{
+    join_with_double_colon, print_abi_with_space, print_constness_with_space, print_where_clause,
+    Buffer, Ending, PrintWithSpace,
+};
+use crate::html::highlight;
+use crate::html::layout::Page;
+use crate::html::markdown::{HeadingOffset, MarkdownSummaryLine};
+use crate::html::url_parts_builder::UrlPartsBuilder;
+
+use askama::Template;
+use itertools::Itertools;
+
+const ITEM_TABLE_OPEN: &str = "
    ";
+const ITEM_TABLE_CLOSE: &str = "
    ";
+const ITEM_TABLE_ROW_OPEN: &str = "
    ";
+const ITEM_TABLE_ROW_CLOSE: &str = "
    ";
+
+// A component in a `use` path, like `string` in std::string::ToString
+struct PathComponent {
+    path: String,
+    name: Symbol,
+}
+
+#[derive(Template)]
+#[template(path = "print_item.html")]
+struct ItemVars<'a> {
+    page: &'a Page<'a>,
+    static_root_path: &'a str,
+    typ: &'a str,
+    name: &'a str,
+    item_type: &'a str,
+    path_components: Vec,
+    stability_since_raw: &'a str,
+    src_href: Option<&'a str>,
+}
+
+/// Calls `print_where_clause` and returns `true` if a `where` clause was generated.
+fn print_where_clause_and_check<'a, 'tcx: 'a>(
+    buffer: &mut Buffer,
+    gens: &'a clean::Generics,
+    cx: &'a Context<'tcx>,
+) -> bool {
+    let len_before = buffer.len();
+    write!(buffer, "{}", print_where_clause(gens, cx, 0, Ending::Newline));
+    len_before != buffer.len()
+}
+
+pub(super) fn print_item(
+    cx: &mut Context<'_>,
+    item: &clean::Item,
+    buf: &mut Buffer,
+    page: &Page<'_>,
+) {
+    debug_assert!(!item.is_stripped());
+    let typ = match *item.kind {
+        clean::ModuleItem(_) => {
+            if item.is_crate() {
+                "Crate "
+            } else {
+                "Module "
+            }
+        }
+        clean::FunctionItem(..) | clean::ForeignFunctionItem(..) => "Function ",
+        clean::TraitItem(..) => "Trait ",
+        clean::StructItem(..) => "Struct ",
+        clean::UnionItem(..) => "Union ",
+        clean::EnumItem(..) => "Enum ",
+        clean::TypedefItem(..) => "Type Definition ",
+        clean::MacroItem(..) => "Macro ",
+        clean::ProcMacroItem(ref mac) => match mac.kind {
+            MacroKind::Bang => "Macro ",
+            MacroKind::Attr => "Attribute Macro ",
+            MacroKind::Derive => "Derive Macro ",
+        },
+        clean::PrimitiveItem(..) => "Primitive Type ",
+        clean::StaticItem(..) | clean::ForeignStaticItem(..) => "Static ",
+        clean::ConstantItem(..) => "Constant ",
+        clean::ForeignTypeItem => "Foreign Type ",
+        clean::KeywordItem => "Keyword ",
+        clean::OpaqueTyItem(..) => "Opaque Type ",
+        clean::TraitAliasItem(..) => "Trait Alias ",
+        _ => {
+            // We don't generate pages for any other type.
+            unreachable!();
+        }
+    };
+    let mut stability_since_raw = Buffer::new();
+    render_stability_since_raw(
+        &mut stability_since_raw,
+        item.stable_since(cx.tcx()),
+        item.const_stability(cx.tcx()),
+        None,
+        None,
+    );
+    let stability_since_raw: String = stability_since_raw.into_inner();
+
+    // Write source tag
+    //
+    // When this item is part of a `crate use` in a downstream crate, the
+    // source link in the downstream documentation will actually come back to
+    // this page, and this link will be auto-clicked. The `id` attribute is
+    // used to find the link to auto-click.
+    let src_href =
+        if cx.include_sources && !item.is_primitive() { cx.src_href(item) } else { None };
+
+    let path_components = if item.is_primitive() || item.is_keyword() {
+        vec![]
+    } else {
+        let cur = &cx.current;
+        let amt = if item.is_mod() { cur.len() - 1 } else { cur.len() };
+        cur.iter()
+            .enumerate()
+            .take(amt)
+            .map(|(i, component)| PathComponent {
+                path: "../".repeat(cur.len() - i - 1),
+                name: *component,
+            })
+            .collect()
+    };
+
+    let item_vars = ItemVars {
+        page,
+        static_root_path: page.get_static_root_path(),
+        typ,
+        name: item.name.as_ref().unwrap().as_str(),
+        item_type: &item.type_().to_string(),
+        path_components,
+        stability_since_raw: &stability_since_raw,
+        src_href: src_href.as_deref(),
+    };
+
+    item_vars.render_into(buf).unwrap();
+
+    match &*item.kind {
+        clean::ModuleItem(ref m) => item_module(buf, cx, item, &m.items),
+        clean::FunctionItem(ref f) | clean::ForeignFunctionItem(ref f) => {
+            item_function(buf, cx, item, f)
+        }
+        clean::TraitItem(ref t) => item_trait(buf, cx, item, t),
+        clean::StructItem(ref s) => item_struct(buf, cx, item, s),
+        clean::UnionItem(ref s) => item_union(buf, cx, item, s),
+        clean::EnumItem(ref e) => item_enum(buf, cx, item, e),
+        clean::TypedefItem(ref t) => item_typedef(buf, cx, item, t),
+        clean::MacroItem(ref m) => item_macro(buf, cx, item, m),
+        clean::ProcMacroItem(ref m) => item_proc_macro(buf, cx, item, m),
+        clean::PrimitiveItem(_) => item_primitive(buf, cx, item),
+        clean::StaticItem(ref i) | clean::ForeignStaticItem(ref i) => item_static(buf, cx, item, i),
+        clean::ConstantItem(ref c) => item_constant(buf, cx, item, c),
+        clean::ForeignTypeItem => item_foreign_type(buf, cx, item),
+        clean::KeywordItem => item_keyword(buf, cx, item),
+        clean::OpaqueTyItem(ref e) => item_opaque_ty(buf, cx, item, e),
+        clean::TraitAliasItem(ref ta) => item_trait_alias(buf, cx, item, ta),
+        _ => {
+            // We don't generate pages for any other type.
+            unreachable!();
+        }
+    }
+}
+
+/// For large structs, enums, unions, etc, determine whether to hide their fields
+fn should_hide_fields(n_fields: usize) -> bool {
+    n_fields > 12
+}
+
+fn toggle_open(w: &mut Buffer, text: impl fmt::Display) {
+    write!(
+        w,
+        "
    \
+            \
+                Show {}\
+            ",
+        text
+    );
+}
+
+fn toggle_close(w: &mut Buffer) {
+    w.write_str("
    ");
+}
+
+fn item_module(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Item, items: &[clean::Item]) {
+    document(w, cx, item, None, HeadingOffset::H2);
+
+    let mut indices = (0..items.len()).filter(|i| !items[*i].is_stripped()).collect::>();
+
+    // the order of item types in the listing
+    fn reorder(ty: ItemType) -> u8 {
+        match ty {
+            ItemType::ExternCrate => 0,
+            ItemType::Import => 1,
+            ItemType::Primitive => 2,
+            ItemType::Module => 3,
+            ItemType::Macro => 4,
+            ItemType::Struct => 5,
+            ItemType::Enum => 6,
+            ItemType::Constant => 7,
+            ItemType::Static => 8,
+            ItemType::Trait => 9,
+            ItemType::Function => 10,
+            ItemType::Typedef => 12,
+            ItemType::Union => 13,
+            _ => 14 + ty as u8,
+        }
+    }
+
+    fn cmp(
+        i1: &clean::Item,
+        i2: &clean::Item,
+        idx1: usize,
+        idx2: usize,
+        tcx: TyCtxt<'_>,
+    ) -> Ordering {
+        let ty1 = i1.type_();
+        let ty2 = i2.type_();
+        if item_ty_to_section(ty1) != item_ty_to_section(ty2)
+            || (ty1 != ty2 && (ty1 == ItemType::ExternCrate || ty2 == ItemType::ExternCrate))
+        {
+            return (reorder(ty1), idx1).cmp(&(reorder(ty2), idx2));
+        }
+        let s1 = i1.stability(tcx).as_ref().map(|s| s.level);
+        let s2 = i2.stability(tcx).as_ref().map(|s| s.level);
+        if let (Some(a), Some(b)) = (s1, s2) {
+            match (a.is_stable(), b.is_stable()) {
+                (true, true) | (false, false) => {}
+                (false, true) => return Ordering::Less,
+                (true, false) => return Ordering::Greater,
+            }
+        }
+        let lhs = i1.name.unwrap_or(kw::Empty);
+        let rhs = i2.name.unwrap_or(kw::Empty);
+        compare_names(lhs.as_str(), rhs.as_str())
+    }
+
+    match cx.shared.module_sorting {
+        ModuleSorting::Alphabetical => {
+            indices.sort_by(|&i1, &i2| cmp(&items[i1], &items[i2], i1, i2, cx.tcx()));
+        }
+        ModuleSorting::DeclarationOrder => {}
+    }
+    // This call is to remove re-export duplicates in cases such as:
+    //
+    // ```
+    // pub(crate) mod foo {
+    //     pub(crate) mod bar {
+    //         pub(crate) trait Double { fn foo(); }
+    //     }
+    // }
+    //
+    // pub(crate) use foo::bar::*;
+    // pub(crate) use foo::*;
+    // ```
+    //
+    // `Double` will appear twice in the generated docs.
+    //
+    // FIXME: This code is quite ugly and could be improved. Small issue: DefId
+    // can be identical even if the elements are different (mostly in imports).
+    // So in case this is an import, we keep everything by adding a "unique id"
+    // (which is the position in the vector).
+    indices.dedup_by_key(|i| {
+        (
+            items[*i].item_id,
+            if items[*i].name.is_some() { Some(full_path(cx, &items[*i])) } else { None },
+            items[*i].type_(),
+            if items[*i].is_import() { *i } else { 0 },
+        )
+    });
+
+    debug!("{:?}", indices);
+    let mut last_section = None;
+
+    for &idx in &indices {
+        let myitem = &items[idx];
+        if myitem.is_stripped() {
+            continue;
+        }
+
+        let my_section = item_ty_to_section(myitem.type_());
+        if Some(my_section) != last_section {
+            if last_section.is_some() {
+                w.write_str(ITEM_TABLE_CLOSE);
+            }
+            last_section = Some(my_section);
+            write!(
+                w,
+                "
    \
+                    {name}\
+                 
    {}",
+                ITEM_TABLE_OPEN,
+                id = cx.derive_id(my_section.id().to_owned()),
+                name = my_section.name(),
+            );
+        }
+
+        match *myitem.kind {
+            clean::ExternCrateItem { ref src } => {
+                use crate::html::format::anchor;
+
+                w.write_str(ITEM_TABLE_ROW_OPEN);
+                match *src {
+                    Some(src) => write!(
+                        w,
+                        "
    {}extern crate {} as {};",
+                        myitem.visibility.print_with_space(myitem.item_id, cx),
+                        anchor(myitem.item_id.expect_def_id(), src, cx),
+                        myitem.name.unwrap(),
+                    ),
+                    None => write!(
+                        w,
+                        "
    {}extern crate {};",
+                        myitem.visibility.print_with_space(myitem.item_id, cx),
+                        anchor(myitem.item_id.expect_def_id(), myitem.name.unwrap(), cx),
+                    ),
+                }
+                w.write_str("
    ");
+                w.write_str(ITEM_TABLE_ROW_CLOSE);
+            }
+
+            clean::ImportItem(ref import) => {
+                let (stab, stab_tags) = if let Some(import_def_id) = import.source.did {
+                    let ast_attrs = cx.tcx().get_attrs_unchecked(import_def_id);
+                    let import_attrs = Box::new(clean::Attributes::from_ast(ast_attrs));
+
+                    // Just need an item with the correct def_id and attrs
+                    let import_item = clean::Item {
+                        item_id: import_def_id.into(),
+                        attrs: import_attrs,
+                        cfg: ast_attrs.cfg(cx.tcx(), &cx.cache().hidden_cfg),
+                        ..myitem.clone()
+                    };
+
+                    let stab = import_item.stability_class(cx.tcx());
+                    let stab_tags = Some(extra_info_tags(&import_item, item, cx.tcx()));
+                    (stab, stab_tags)
+                } else {
+                    (None, None)
+                };
+
+                let add = if stab.is_some() { " " } else { "" };
+
+                w.write_str(ITEM_TABLE_ROW_OPEN);
+                let id = match import.kind {
+                    clean::ImportKind::Simple(s) => {
+                        format!(" id=\"{}\"", cx.derive_id(format!("reexport.{}", s)))
+                    }
+                    clean::ImportKind::Glob => String::new(),
+                };
+                write!(
+                    w,
+                    "
    \
+                         {vis}{imp}\
+                     
    \
+                     
    {stab_tags}
    ",
+                    stab = stab.unwrap_or_default(),
+                    vis = myitem.visibility.print_with_space(myitem.item_id, cx),
+                    imp = import.print(cx),
+                    stab_tags = stab_tags.unwrap_or_default(),
+                );
+                w.write_str(ITEM_TABLE_ROW_CLOSE);
+            }
+
+            _ => {
+                if myitem.name.is_none() {
+                    continue;
+                }
+
+                let unsafety_flag = match *myitem.kind {
+                    clean::FunctionItem(_) | clean::ForeignFunctionItem(_)
+                        if myitem.fn_header(cx.tcx()).unwrap().unsafety
+                            == hir::Unsafety::Unsafe =>
+                    {
+                        "⚠"
+                    }
+                    _ => "",
+                };
+
+                let stab = myitem.stability_class(cx.tcx());
+                let add = if stab.is_some() { " " } else { "" };
+
+                let visibility_emoji = match myitem.visibility {
+                    clean::Visibility::Restricted(_) => {
+                        " 🔒 "
+                    }
+                    _ => "",
+                };
+
+                let doc_value = myitem.doc_value().unwrap_or_default();
+                w.write_str(ITEM_TABLE_ROW_OPEN);
+                write!(
+                    w,
+                    "
    \
+                        {name}\
+                        {visibility_emoji}\
+                        {unsafety_flag}\
+                        {stab_tags}\
+                     
    \
+                     
    {docs}
    ",
+                    name = myitem.name.unwrap(),
+                    visibility_emoji = visibility_emoji,
+                    stab_tags = extra_info_tags(myitem, item, cx.tcx()),
+                    docs = MarkdownSummaryLine(&doc_value, &myitem.links(cx)).into_string(),
+                    class = myitem.type_(),
+                    add = add,
+                    stab = stab.unwrap_or_default(),
+                    unsafety_flag = unsafety_flag,
+                    href = item_path(myitem.type_(), myitem.name.unwrap().as_str()),
+                    title = [full_path(cx, myitem), myitem.type_().to_string()]
+                        .iter()
+                        .filter_map(|s| if !s.is_empty() { Some(s.as_str()) } else { None })
+                        .collect::>()
+                        .join(" "),
+                );
+                w.write_str(ITEM_TABLE_ROW_CLOSE);
+            }
+        }
+    }
+
+    if last_section.is_some() {
+        w.write_str(ITEM_TABLE_CLOSE);
+    }
+}
+
+/// Render the stability, deprecation and portability tags that are displayed in the item's summary
+/// at the module level.
+fn extra_info_tags(item: &clean::Item, parent: &clean::Item, tcx: TyCtxt<'_>) -> String {
+    let mut tags = String::new();
+
+    fn tag_html(class: &str, title: &str, contents: &str) -> String {
+        format!(r#"{}"#, class, Escape(title), contents)
+    }
+
+    // The trailing space after each tag is to space it properly against the rest of the docs.
+    if let Some(depr) = &item.deprecation(tcx) {
+        let mut message = "Deprecated";
+        if !stability::deprecation_in_effect(depr) {
+            message = "Deprecation planned";
+        }
+        tags += &tag_html("deprecated", "", message);
+    }
+
+    // The "rustc_private" crates are permanently unstable so it makes no sense
+    // to render "unstable" everywhere.
+    if item.stability(tcx).as_ref().map(|s| s.is_unstable() && s.feature != sym::rustc_private)
+        == Some(true)
+    {
+        tags += &tag_html("unstable", "", "Experimental");
+    }
+
+    let cfg = match (&item.cfg, parent.cfg.as_ref()) {
+        (Some(cfg), Some(parent_cfg)) => cfg.simplify_with(parent_cfg),
+        (cfg, _) => cfg.as_deref().cloned(),
+    };
+
+    debug!("Portability {:?} - {:?} = {:?}", item.cfg, parent.cfg, cfg);
+    if let Some(ref cfg) = cfg {
+        tags += &tag_html("portability", &cfg.render_long_plain(), &cfg.render_short_html());
+    }
+
+    tags
+}
+
+fn item_function(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, f: &clean::Function) {
+    let header = it.fn_header(cx.tcx()).expect("printing a function which isn't a function");
+    let constness = print_constness_with_space(&header.constness, it.const_stability(cx.tcx()));
+    let unsafety = header.unsafety.print_with_space();
+    let abi = print_abi_with_space(header.abi).to_string();
+    let asyncness = header.asyncness.print_with_space();
+    let visibility = it.visibility.print_with_space(it.item_id, cx).to_string();
+    let name = it.name.unwrap();
+
+    let generics_len = format!("{:#}", f.generics.print(cx)).len();
+    let header_len = "fn ".len()
+        + visibility.len()
+        + constness.len()
+        + asyncness.len()
+        + unsafety.len()
+        + abi.len()
+        + name.as_str().len()
+        + generics_len;
+
+    wrap_into_docblock(w, |w| {
+        wrap_item(w, "fn", |w| {
+            render_attributes_in_pre(w, it, "");
+            w.reserve(header_len);
+            write!(
+                w,
+                "{vis}{constness}{asyncness}{unsafety}{abi}fn \
+                 {name}{generics}{decl}{notable_traits}{where_clause}",
+                vis = visibility,
+                constness = constness,
+                asyncness = asyncness,
+                unsafety = unsafety,
+                abi = abi,
+                name = name,
+                generics = f.generics.print(cx),
+                where_clause = print_where_clause(&f.generics, cx, 0, Ending::Newline),
+                decl = f.decl.full_print(header_len, 0, header.asyncness, cx),
+                notable_traits = notable_traits_decl(&f.decl, cx),
+            );
+        });
+    });
+    document(w, cx, it, None, HeadingOffset::H2)
+}
+
+fn item_trait(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &clean::Trait) {
+    let bounds = bounds(&t.bounds, false, cx);
+    let required_types = t.items.iter().filter(|m| m.is_ty_associated_type()).collect::>();
+    let provided_types = t.items.iter().filter(|m| m.is_associated_type()).collect::>();
+    let required_consts = t.items.iter().filter(|m| m.is_ty_associated_const()).collect::>();
+    let provided_consts = t.items.iter().filter(|m| m.is_associated_const()).collect::>();
+    let required_methods = t.items.iter().filter(|m| m.is_ty_method()).collect::>();
+    let provided_methods = t.items.iter().filter(|m| m.is_method()).collect::>();
+    let count_types = required_types.len() + provided_types.len();
+    let count_consts = required_consts.len() + provided_consts.len();
+    let count_methods = required_methods.len() + provided_methods.len();
+    let must_implement_one_of_functions =
+        cx.tcx().trait_def(t.def_id).must_implement_one_of.clone();
+
+    // Output the trait definition
+    wrap_into_docblock(w, |w| {
+        wrap_item(w, "trait", |w| {
+            render_attributes_in_pre(w, it, "");
+            write!(
+                w,
+                "{}{}{}trait {}{}{}",
+                it.visibility.print_with_space(it.item_id, cx),
+                t.unsafety(cx.tcx()).print_with_space(),
+                if t.is_auto(cx.tcx()) { "auto " } else { "" },
+                it.name.unwrap(),
+                t.generics.print(cx),
+                bounds
+            );
+
+            if !t.generics.where_predicates.is_empty() {
+                write!(w, "{}", print_where_clause(&t.generics, cx, 0, Ending::Newline));
+            } else {
+                w.write_str(" ");
+            }
+
+            if t.items.is_empty() {
+                w.write_str("{ }");
+            } else {
+                // FIXME: we should be using a derived_id for the Anchors here
+                w.write_str("{\n");
+                let mut toggle = false;
+
+                // If there are too many associated types, hide _everything_
+                if should_hide_fields(count_types) {
+                    toggle = true;
+                    toggle_open(
+                        w,
+                        format_args!(
+                            "{} associated items",
+                            count_types + count_consts + count_methods
+                        ),
+                    );
+                }
+                for types in [&required_types, &provided_types] {
+                    for t in types {
+                        render_assoc_item(
+                            w,
+                            t,
+                            AssocItemLink::Anchor(None),
+                            ItemType::Trait,
+                            cx,
+                            RenderMode::Normal,
+                        );
+                        w.write_str(";\n");
+                    }
+                }
+                // If there are too many associated constants, hide everything after them
+                // We also do this if the types + consts is large because otherwise we could
+                // render a bunch of types and _then_ a bunch of consts just because both were
+                // _just_ under the limit
+                if !toggle && should_hide_fields(count_types + count_consts) {
+                    toggle = true;
+                    toggle_open(
+                        w,
+                        format_args!(
+                            "{} associated constant{} and {} method{}",
+                            count_consts,
+                            pluralize(count_consts),
+                            count_methods,
+                            pluralize(count_methods),
+                        ),
+                    );
+                }
+                if count_types != 0 && (count_consts != 0 || count_methods != 0) {
+                    w.write_str("\n");
+                }
+                for consts in [&required_consts, &provided_consts] {
+                    for c in consts {
+                        render_assoc_item(
+                            w,
+                            c,
+                            AssocItemLink::Anchor(None),
+                            ItemType::Trait,
+                            cx,
+                            RenderMode::Normal,
+                        );
+                        w.write_str(";\n");
+                    }
+                }
+                if !toggle && should_hide_fields(count_methods) {
+                    toggle = true;
+                    toggle_open(w, format_args!("{} methods", count_methods));
+                }
+                if count_consts != 0 && count_methods != 0 {
+                    w.write_str("\n");
+                }
+                for (pos, m) in required_methods.iter().enumerate() {
+                    render_assoc_item(
+                        w,
+                        m,
+                        AssocItemLink::Anchor(None),
+                        ItemType::Trait,
+                        cx,
+                        RenderMode::Normal,
+                    );
+                    w.write_str(";\n");
+
+                    if pos < required_methods.len() - 1 {
+                        w.write_str("");
+                    }
+                }
+                if !required_methods.is_empty() && !provided_methods.is_empty() {
+                    w.write_str("\n");
+                }
+                for (pos, m) in provided_methods.iter().enumerate() {
+                    render_assoc_item(
+                        w,
+                        m,
+                        AssocItemLink::Anchor(None),
+                        ItemType::Trait,
+                        cx,
+                        RenderMode::Normal,
+                    );
+                    match *m.kind {
+                        clean::MethodItem(ref inner, _)
+                            if !inner.generics.where_predicates.is_empty() =>
+                        {
+                            w.write_str(",\n    { ... }\n");
+                        }
+                        _ => {
+                            w.write_str(" { ... }\n");
+                        }
+                    }
+
+                    if pos < provided_methods.len() - 1 {
+                        w.write_str("");
+                    }
+                }
+                if toggle {
+                    toggle_close(w);
+                }
+                w.write_str("}");
+            }
+        });
+    });
+
+    // Trait documentation
+    document(w, cx, it, None, HeadingOffset::H2);
+
+    fn write_small_section_header(w: &mut Buffer, id: &str, title: &str, extra_content: &str) {
+        write!(
+            w,
+            "
    \
+                {1}\
+             
    {2}",
+            id, title, extra_content
+        )
+    }
+
+    fn trait_item(w: &mut Buffer, cx: &mut Context<'_>, m: &clean::Item, t: &clean::Item) {
+        let name = m.name.unwrap();
+        info!("Documenting {} on {:?}", name, t.name);
+        let item_type = m.type_();
+        let id = cx.derive_id(format!("{}.{}", item_type, name));
+        let mut content = Buffer::empty_from(w);
+        document(&mut content, cx, m, Some(t), HeadingOffset::H5);
+        let toggled = !content.is_empty();
+        if toggled {
+            write!(w, "
    ");
+        }
+        write!(w, "
    ", id);
+        write!(w, "
    ");
+
+        let has_stability = render_stability_since(w, m, t, cx.tcx());
+        if has_stability {
+            w.write_str(" · ");
+        }
+        write_srclink(cx, m, w);
+        write!(w, "
    ");
+        write!(w, "
    ");
+        render_assoc_item(
+            w,
+            m,
+            AssocItemLink::Anchor(Some(&id)),
+            ItemType::Impl,
+            cx,
+            RenderMode::Normal,
+        );
+        w.write_str("
    ");
+        w.write_str("
    ");
+        if toggled {
+            write!(w, "    ");
+            w.push_buffer(content);
+            write!(w, "
    ");
+        }
+    }
+
+    if !required_types.is_empty() {
+        write_small_section_header(
+            w,
+            "required-associated-types",
+            "Required Associated Types",
+            "
    ",
+        );
+        for t in required_types {
+            trait_item(w, cx, t, it);
+        }
+        w.write_str("
    ");
+    }
+    if !provided_types.is_empty() {
+        write_small_section_header(
+            w,
+            "provided-associated-types",
+            "Provided Associated Types",
+            "
    ",
+        );
+        for t in provided_types {
+            trait_item(w, cx, t, it);
+        }
+        w.write_str("
    ");
+    }
+
+    if !required_consts.is_empty() {
+        write_small_section_header(
+            w,
+            "required-associated-consts",
+            "Required Associated Constants",
+            "
    ",
+        );
+        for t in required_consts {
+            trait_item(w, cx, t, it);
+        }
+        w.write_str("
    ");
+    }
+    if !provided_consts.is_empty() {
+        write_small_section_header(
+            w,
+            "provided-associated-consts",
+            "Provided Associated Constants",
+            "
    ",
+        );
+        for t in provided_consts {
+            trait_item(w, cx, t, it);
+        }
+        w.write_str("
    ");
+    }
+
+    // Output the documentation for each function individually
+    if !required_methods.is_empty() || must_implement_one_of_functions.is_some() {
+        write_small_section_header(
+            w,
+            "required-methods",
+            "Required Methods",
+            "
    ",
+        );
+
+        if let Some(list) = must_implement_one_of_functions.as_deref() {
+            write!(
+                w,
+                "
    At least one of the `{}` methods is required.
    ",
+                list.iter().join("`, `")
+            );
+        }
+
+        for m in required_methods {
+            trait_item(w, cx, m, it);
+        }
+        w.write_str("
    ");
+    }
+    if !provided_methods.is_empty() {
+        write_small_section_header(
+            w,
+            "provided-methods",
+            "Provided Methods",
+            "
    ",
+        );
+        for m in provided_methods {
+            trait_item(w, cx, m, it);
+        }
+        w.write_str("
    ");
+    }
+
+    // If there are methods directly on this trait object, render them here.
+    render_assoc_items(w, cx, it, it.item_id.expect_def_id(), AssocItemRender::All);
+
+    let cloned_shared = Rc::clone(&cx.shared);
+    let cache = &cloned_shared.cache;
+    let mut extern_crates = FxHashSet::default();
+    if let Some(implementors) = cache.implementors.get(&it.item_id.expect_def_id()) {
+        // The DefId is for the first Type found with that name. The bool is
+        // if any Types with the same name but different DefId have been found.
+        let mut implementor_dups: FxHashMap = FxHashMap::default();
+        for implementor in implementors {
+            if let Some(did) = implementor.inner_impl().for_.without_borrowed_ref().def_id(cache) &&
+                !did.is_local() {
+                extern_crates.insert(did.krate);
+            }
+            match implementor.inner_impl().for_.without_borrowed_ref() {
+                clean::Type::Path { ref path } if !path.is_assoc_ty() => {
+                    let did = path.def_id();
+                    let &mut (prev_did, ref mut has_duplicates) =
+                        implementor_dups.entry(path.last()).or_insert((did, false));
+                    if prev_did != did {
+                        *has_duplicates = true;
+                    }
+                }
+                _ => {}
+            }
+        }
+
+        let (local, foreign) =
+            implementors.iter().partition::, _>(|i| i.is_on_local_type(cx));
+
+        let (mut synthetic, mut concrete): (Vec<&&Impl>, Vec<&&Impl>) =
+            local.iter().partition(|i| i.inner_impl().kind.is_auto());
+
+        synthetic.sort_by(|a, b| compare_impl(a, b, cx));
+        concrete.sort_by(|a, b| compare_impl(a, b, cx));
+
+        if !foreign.is_empty() {
+            write_small_section_header(w, "foreign-impls", "Implementations on Foreign Types", "");
+
+            for implementor in foreign {
+                let provided_methods = implementor.inner_impl().provided_trait_methods(cx.tcx());
+                let assoc_link =
+                    AssocItemLink::GotoSource(implementor.impl_item.item_id, &provided_methods);
+                render_impl(
+                    w,
+                    cx,
+                    implementor,
+                    it,
+                    assoc_link,
+                    RenderMode::Normal,
+                    None,
+                    &[],
+                    ImplRenderingParameters {
+                        show_def_docs: false,
+                        show_default_items: false,
+                        show_non_assoc_items: true,
+                        toggle_open_by_default: false,
+                    },
+                );
+            }
+        }
+
+        write_small_section_header(
+            w,
+            "implementors",
+            "Implementors",
+            "
    ",
+        );
+        for implementor in concrete {
+            render_implementor(cx, implementor, it, w, &implementor_dups, &[]);
+        }
+        w.write_str("
    ");
+
+        if t.is_auto(cx.tcx()) {
+            write_small_section_header(
+                w,
+                "synthetic-implementors",
+                "Auto implementors",
+                "
    ",
+            );
+            for implementor in synthetic {
+                render_implementor(
+                    cx,
+                    implementor,
+                    it,
+                    w,
+                    &implementor_dups,
+                    &collect_paths_for_type(implementor.inner_impl().for_.clone(), cache),
+                );
+            }
+            w.write_str("
    ");
+        }
+    } else {
+        // even without any implementations to write in, we still want the heading and list, so the
+        // implementors javascript file pulled in below has somewhere to write the impls into
+        write_small_section_header(
+            w,
+            "implementors",
+            "Implementors",
+            "
    ",
+        );
+
+        if t.is_auto(cx.tcx()) {
+            write_small_section_header(
+                w,
+                "synthetic-implementors",
+                "Auto implementors",
+                "
    ",
+            );
+        }
+    }
+
+    // Include implementors in crates that depend on the current crate.
+    //
+    // This is complicated by the way rustdoc is invoked, which is basically
+    // the same way rustc is invoked: it gets called, one at a time, for each
+    // crate. When building the rustdocs for the current crate, rustdoc can
+    // see crate metadata for its dependencies, but cannot see metadata for its
+    // dependents.
+    //
+    // To make this work, we generate a "hook" at this stage, and our
+    // dependents can "plug in" to it when they build. For simplicity's sake,
+    // it's [JSONP]: a JavaScript file with the data we need (and can parse),
+    // surrounded by a tiny wrapper that the Rust side ignores, but allows the
+    // JavaScript side to include without having to worry about Same Origin
+    // Policy. The code for *that* is in `write_shared.rs`.
+    //
+    // This is further complicated by `#[doc(inline)]`. We want all copies
+    // of an inlined trait to reference the same JS file, to address complex
+    // dependency graphs like this one (lower crates depend on higher crates):
+    //
+    // ```text
+    //  --------------------------------------------
+    //  |            crate A: trait Foo            |
+    //  --------------------------------------------
+    //      |                               |
+    //  --------------------------------    |
+    //  | crate B: impl A::Foo for Bar |    |
+    //  --------------------------------    |
+    //      |                               |
+    //  ---------------------------------------------
+    //  | crate C: #[doc(inline)] use A::Foo as Baz |
+    //  |          impl Baz for Quux                |
+    //  ---------------------------------------------
+    // ```
+    //
+    // Basically, we want `C::Baz` and `A::Foo` to show the same set of
+    // impls, which is easier if they both treat `/implementors/A/trait.Foo.js`
+    // as the Single Source of Truth.
+    //
+    // We also want the `impl Baz for Quux` to be written to
+    // `trait.Foo.js`. However, when we generate plain HTML for `C::Baz`,
+    // we're going to want to generate plain HTML for `impl Baz for Quux` too,
+    // because that'll load faster, and it's better for SEO. And we don't want
+    // the same impl to show up twice on the same page.
+    //
+    // To make this work, the implementors JS file has a structure kinda
+    // like this:
+    //
+    // ```js
+    // JSONP({
+    // "B": {"impl A::Foo for Bar"},
+    // "C": {"impl Baz for Quux"},
+    // });
+    // ```
+    //
+    // First of all, this means we can rebuild a crate, and it'll replace its own
+    // data if something changes. That is, `rustdoc` is idempotent. The other
+    // advantage is that we can list the crates that get included in the HTML,
+    // and ignore them when doing the JavaScript-based part of rendering.
+    // So C's HTML will have something like this:
+    //
+    // ```html
+    // 
+    // ```
+    //
+    // And, when the JS runs, anything in data-ignore-extern-crates is known
+    // to already be in the HTML, and will be ignored.
+    //
+    // [JSONP]: https://en.wikipedia.org/wiki/JSONP
+    let mut js_src_path: UrlPartsBuilder = std::iter::repeat("..")
+        .take(cx.current.len())
+        .chain(std::iter::once("implementors"))
+        .collect();
+    if let Some(did) = it.item_id.as_def_id() &&
+        let get_extern = { || cache.external_paths.get(&did).map(|s| s.0.clone()) } &&
+        let Some(fqp) = cache.exact_paths.get(&did).cloned().or_else(get_extern) {
+        js_src_path.extend(fqp[..fqp.len() - 1].iter().copied());
+        js_src_path.push_fmt(format_args!("{}.{}.js", it.type_(), fqp.last().unwrap()));
+    } else {
+        js_src_path.extend(cx.current.iter().copied());
+        js_src_path.push_fmt(format_args!("{}.{}.js", it.type_(), it.name.unwrap()));
+    }
+    let extern_crates = extern_crates
+        .into_iter()
+        .map(|cnum| cx.shared.tcx.crate_name(cnum).to_string())
+        .collect::>()
+        .join(",");
+    write!(
+        w,
+        "",
+        src = js_src_path.finish(),
+    );
+}
+
+fn item_trait_alias(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &clean::TraitAlias) {
+    wrap_into_docblock(w, |w| {
+        wrap_item(w, "trait-alias", |w| {
+            render_attributes_in_pre(w, it, "");
+            write!(
+                w,
+                "trait {}{}{} = {};",
+                it.name.unwrap(),
+                t.generics.print(cx),
+                print_where_clause(&t.generics, cx, 0, Ending::Newline),
+                bounds(&t.bounds, true, cx)
+            );
+        });
+    });
+
+    document(w, cx, it, None, HeadingOffset::H2);
+
+    // Render any items associated directly to this alias, as otherwise they
+    // won't be visible anywhere in the docs. It would be nice to also show
+    // associated items from the aliased type (see discussion in #32077), but
+    // we need #14072 to make sense of the generics.
+    render_assoc_items(w, cx, it, it.item_id.expect_def_id(), AssocItemRender::All)
+}
+
+fn item_opaque_ty(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &clean::OpaqueTy) {
+    wrap_into_docblock(w, |w| {
+        wrap_item(w, "opaque", |w| {
+            render_attributes_in_pre(w, it, "");
+            write!(
+                w,
+                "type {}{}{where_clause} = impl {bounds};",
+                it.name.unwrap(),
+                t.generics.print(cx),
+                where_clause = print_where_clause(&t.generics, cx, 0, Ending::Newline),
+                bounds = bounds(&t.bounds, false, cx),
+            );
+        });
+    });
+
+    document(w, cx, it, None, HeadingOffset::H2);
+
+    // Render any items associated directly to this alias, as otherwise they
+    // won't be visible anywhere in the docs. It would be nice to also show
+    // associated items from the aliased type (see discussion in #32077), but
+    // we need #14072 to make sense of the generics.
+    render_assoc_items(w, cx, it, it.item_id.expect_def_id(), AssocItemRender::All)
+}
+
+fn item_typedef(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &clean::Typedef) {
+    fn write_content(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean::Typedef) {
+        wrap_item(w, "typedef", |w| {
+            render_attributes_in_pre(w, it, "");
+            write!(w, "{}", it.visibility.print_with_space(it.item_id, cx));
+            write!(
+                w,
+                "type {}{}{where_clause} = {type_};",
+                it.name.unwrap(),
+                t.generics.print(cx),
+                where_clause = print_where_clause(&t.generics, cx, 0, Ending::Newline),
+                type_ = t.type_.print(cx),
+            );
+        });
+    }
+
+    wrap_into_docblock(w, |w| write_content(w, cx, it, t));
+
+    document(w, cx, it, None, HeadingOffset::H2);
+
+    let def_id = it.item_id.expect_def_id();
+    // Render any items associated directly to this alias, as otherwise they
+    // won't be visible anywhere in the docs. It would be nice to also show
+    // associated items from the aliased type (see discussion in #32077), but
+    // we need #14072 to make sense of the generics.
+    render_assoc_items(w, cx, it, def_id, AssocItemRender::All);
+    document_type_layout(w, cx, def_id);
+}
+
+fn item_union(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, s: &clean::Union) {
+    wrap_into_docblock(w, |w| {
+        wrap_item(w, "union", |w| {
+            render_attributes_in_pre(w, it, "");
+            render_union(w, it, Some(&s.generics), &s.fields, "", cx);
+        });
+    });
+
+    document(w, cx, it, None, HeadingOffset::H2);
+
+    let mut fields = s
+        .fields
+        .iter()
+        .filter_map(|f| match *f.kind {
+            clean::StructFieldItem(ref ty) => Some((f, ty)),
+            _ => None,
+        })
+        .peekable();
+    if fields.peek().is_some() {
+        write!(
+            w,
+            "
    \
+                Fields\
+            
    "
+        );
+        for (field, ty) in fields {
+            let name = field.name.expect("union field name");
+            let id = format!("{}.{}", ItemType::StructField, name);
+            write!(
+                w,
+                "\
+                     \
+                     {name}: {ty}\
+                 ",
+                id = id,
+                name = name,
+                shortty = ItemType::StructField,
+                ty = ty.print(cx),
+            );
+            if let Some(stability_class) = field.stability_class(cx.tcx()) {
+                write!(w, "", stab = stability_class);
+            }
+            document(w, cx, field, Some(it), HeadingOffset::H3);
+        }
+    }
+    let def_id = it.item_id.expect_def_id();
+    render_assoc_items(w, cx, it, def_id, AssocItemRender::All);
+    document_type_layout(w, cx, def_id);
+}
+
+fn print_tuple_struct_fields(w: &mut Buffer, cx: &Context<'_>, s: &[clean::Item]) {
+    for (i, ty) in s.iter().enumerate() {
+        if i > 0 {
+            w.write_str(", ");
+        }
+        match *ty.kind {
+            clean::StrippedItem(box clean::StructFieldItem(_)) => w.write_str("_"),
+            clean::StructFieldItem(ref ty) => write!(w, "{}", ty.print(cx)),
+            _ => unreachable!(),
+        }
+    }
+}
+
+fn item_enum(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, e: &clean::Enum) {
+    let count_variants = e.variants().count();
+    wrap_into_docblock(w, |w| {
+        wrap_item(w, "enum", |w| {
+            render_attributes_in_pre(w, it, "");
+            write!(
+                w,
+                "{}enum {}{}",
+                it.visibility.print_with_space(it.item_id, cx),
+                it.name.unwrap(),
+                e.generics.print(cx),
+            );
+            if !print_where_clause_and_check(w, &e.generics, cx) {
+                // If there wasn't a `where` clause, we add a whitespace.
+                w.write_str(" ");
+            }
+
+            let variants_stripped = e.has_stripped_entries();
+            if count_variants == 0 && !variants_stripped {
+                w.write_str("{}");
+            } else {
+                w.write_str("{\n");
+                let toggle = should_hide_fields(count_variants);
+                if toggle {
+                    toggle_open(w, format_args!("{} variants", count_variants));
+                }
+                for v in e.variants() {
+                    w.write_str("    ");
+                    let name = v.name.unwrap();
+                    match *v.kind {
+                        clean::VariantItem(ref var) => match var {
+                            clean::Variant::CLike => write!(w, "{}", name),
+                            clean::Variant::Tuple(ref s) => {
+                                write!(w, "{}(", name);
+                                print_tuple_struct_fields(w, cx, s);
+                                w.write_str(")");
+                            }
+                            clean::Variant::Struct(ref s) => {
+                                render_struct(
+                                    w,
+                                    v,
+                                    None,
+                                    s.struct_type,
+                                    &s.fields,
+                                    "    ",
+                                    false,
+                                    cx,
+                                );
+                            }
+                        },
+                        _ => unreachable!(),
+                    }
+                    w.write_str(",\n");
+                }
+
+                if variants_stripped {
+                    w.write_str("    // some variants omitted\n");
+                }
+                if toggle {
+                    toggle_close(w);
+                }
+                w.write_str("}");
+            }
+        });
+    });
+
+    document(w, cx, it, None, HeadingOffset::H2);
+
+    if count_variants != 0 {
+        write!(
+            w,
+            "
    \
+                Variants{}\
+            
    ",
+            document_non_exhaustive_header(it)
+        );
+        document_non_exhaustive(w, it);
+        for variant in e.variants() {
+            let id = cx.derive_id(format!("{}.{}", ItemType::Variant, variant.name.unwrap()));
+            write!(
+                w,
+                "
    \
+                    \
+                    {name}",
+                id = id,
+                name = variant.name.unwrap()
+            );
+            if let clean::VariantItem(clean::Variant::Tuple(ref s)) = *variant.kind {
+                w.write_str("(");
+                print_tuple_struct_fields(w, cx, s);
+                w.write_str(")");
+            }
+            w.write_str("");
+            render_stability_since(w, variant, it, cx.tcx());
+            w.write_str("
    ");
+
+            use crate::clean::Variant;
+
+            let heading_and_fields = match &*variant.kind {
+                clean::VariantItem(Variant::Struct(s)) => Some(("Fields", &s.fields)),
+                // Documentation on tuple variant fields is rare, so to reduce noise we only emit
+                // the section if at least one field is documented.
+                clean::VariantItem(Variant::Tuple(fields))
+                    if fields.iter().any(|f| f.doc_value().is_some()) =>
+                {
+                    Some(("Tuple Fields", fields))
+                }
+                _ => None,
+            };
+
+            if let Some((heading, fields)) = heading_and_fields {
+                let variant_id =
+                    cx.derive_id(format!("{}.{}.fields", ItemType::Variant, variant.name.unwrap()));
+                write!(w, "
    ", id = variant_id);
+                write!(w, "
    {heading}
    ", heading = heading);
+                document_non_exhaustive(w, variant);
+                for field in fields {
+                    match *field.kind {
+                        clean::StrippedItem(box clean::StructFieldItem(_)) => {}
+                        clean::StructFieldItem(ref ty) => {
+                            let id = cx.derive_id(format!(
+                                "variant.{}.field.{}",
+                                variant.name.unwrap(),
+                                field.name.unwrap()
+                            ));
+                            write!(
+                                w,
+                                "
    \
+                                 \
+                                     \
+                                     {f}: {t}\
+                                 ",
+                                id = id,
+                                f = field.name.unwrap(),
+                                t = ty.print(cx)
+                            );
+                            document(w, cx, field, Some(variant), HeadingOffset::H5);
+                            write!(w, "
    ");
+                        }
+                        _ => unreachable!(),
+                    }
+                }
+                w.write_str("
    ");
+            }
+
+            document(w, cx, variant, Some(it), HeadingOffset::H4);
+        }
+    }
+    let def_id = it.item_id.expect_def_id();
+    render_assoc_items(w, cx, it, def_id, AssocItemRender::All);
+    document_type_layout(w, cx, def_id);
+}
+
+fn item_macro(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &clean::Macro) {
+    wrap_into_docblock(w, |w| {
+        highlight::render_with_highlighting(
+            &t.source,
+            w,
+            Some("macro"),
+            None,
+            None,
+            it.span(cx.tcx()).inner().edition(),
+            None,
+            None,
+            None,
+        );
+    });
+    document(w, cx, it, None, HeadingOffset::H2)
+}
+
+fn item_proc_macro(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, m: &clean::ProcMacro) {
+    wrap_into_docblock(w, |w| {
+        let name = it.name.expect("proc-macros always have names");
+        match m.kind {
+            MacroKind::Bang => {
+                wrap_item(w, "macro", |w| {
+                    write!(w, "{}!() {{ /* proc-macro */ }}", name);
+                });
+            }
+            MacroKind::Attr => {
+                wrap_item(w, "attr", |w| {
+                    write!(w, "#[{}]", name);
+                });
+            }
+            MacroKind::Derive => {
+                wrap_item(w, "derive", |w| {
+                    write!(w, "#[derive({})]", name);
+                    if !m.helpers.is_empty() {
+                        w.push_str("\n{\n");
+                        w.push_str("    // Attributes available to this derive:\n");
+                        for attr in &m.helpers {
+                            writeln!(w, "    #[{}]", attr);
+                        }
+                        w.push_str("}\n");
+                    }
+                });
+            }
+        }
+    });
+    document(w, cx, it, None, HeadingOffset::H2)
+}
+
+fn item_primitive(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item) {
+    document(w, cx, it, None, HeadingOffset::H2);
+    render_assoc_items(w, cx, it, it.item_id.expect_def_id(), AssocItemRender::All)
+}
+
+fn item_constant(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, c: &clean::Constant) {
+    wrap_into_docblock(w, |w| {
+        wrap_item(w, "const", |w| {
+            render_attributes_in_code(w, it);
+
+            write!(
+                w,
+                "{vis}const {name}: {typ}",
+                vis = it.visibility.print_with_space(it.item_id, cx),
+                name = it.name.unwrap(),
+                typ = c.type_.print(cx),
+            );
+
+            // FIXME: The code below now prints
+            //            ` = _; // 100i32`
+            //        if the expression is
+            //            `50 + 50`
+            //        which looks just wrong.
+            //        Should we print
+            //            ` = 100i32;`
+            //        instead?
+
+            let value = c.value(cx.tcx());
+            let is_literal = c.is_literal(cx.tcx());
+            let expr = c.expr(cx.tcx());
+            if value.is_some() || is_literal {
+                write!(w, " = {expr};", expr = Escape(&expr));
+            } else {
+                w.write_str(";");
+            }
+
+            if !is_literal {
+                if let Some(value) = &value {
+                    let value_lowercase = value.to_lowercase();
+                    let expr_lowercase = expr.to_lowercase();
+
+                    if value_lowercase != expr_lowercase
+                        && value_lowercase.trim_end_matches("i32") != expr_lowercase
+                    {
+                        write!(w, " // {value}", value = Escape(value));
+                    }
+                }
+            }
+        });
+    });
+
+    document(w, cx, it, None, HeadingOffset::H2)
+}
+
+fn item_struct(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, s: &clean::Struct) {
+    wrap_into_docblock(w, |w| {
+        wrap_item(w, "struct", |w| {
+            render_attributes_in_code(w, it);
+            render_struct(w, it, Some(&s.generics), s.struct_type, &s.fields, "", true, cx);
+        });
+    });
+
+    document(w, cx, it, None, HeadingOffset::H2);
+
+    let mut fields = s
+        .fields
+        .iter()
+        .filter_map(|f| match *f.kind {
+            clean::StructFieldItem(ref ty) => Some((f, ty)),
+            _ => None,
+        })
+        .peekable();
+    if let CtorKind::Fictive | CtorKind::Fn = s.struct_type {
+        if fields.peek().is_some() {
+            write!(
+                w,
+                "
    \
+                     {}{}\
+                 
    ",
+                if let CtorKind::Fictive = s.struct_type { "Fields" } else { "Tuple Fields" },
+                document_non_exhaustive_header(it)
+            );
+            document_non_exhaustive(w, it);
+            for (index, (field, ty)) in fields.enumerate() {
+                let field_name =
+                    field.name.map_or_else(|| index.to_string(), |sym| sym.as_str().to_string());
+                let id = cx.derive_id(format!("{}.{}", ItemType::StructField, field_name));
+                write!(
+                    w,
+                    "\
+                         \
+                         {name}: {ty}\
+                     ",
+                    item_type = ItemType::StructField,
+                    id = id,
+                    name = field_name,
+                    ty = ty.print(cx)
+                );
+                document(w, cx, field, Some(it), HeadingOffset::H3);
+            }
+        }
+    }
+    let def_id = it.item_id.expect_def_id();
+    render_assoc_items(w, cx, it, def_id, AssocItemRender::All);
+    document_type_layout(w, cx, def_id);
+}
+
+fn item_static(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, s: &clean::Static) {
+    wrap_into_docblock(w, |w| {
+        wrap_item(w, "static", |w| {
+            render_attributes_in_code(w, it);
+            write!(
+                w,
+                "{vis}static {mutability}{name}: {typ}",
+                vis = it.visibility.print_with_space(it.item_id, cx),
+                mutability = s.mutability.print_with_space(),
+                name = it.name.unwrap(),
+                typ = s.type_.print(cx)
+            );
+        });
+    });
+    document(w, cx, it, None, HeadingOffset::H2)
+}
+
+fn item_foreign_type(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item) {
+    wrap_into_docblock(w, |w| {
+        wrap_item(w, "foreigntype", |w| {
+            w.write_str("extern {\n");
+            render_attributes_in_code(w, it);
+            write!(
+                w,
+                "    {}type {};\n}}",
+                it.visibility.print_with_space(it.item_id, cx),
+                it.name.unwrap(),
+            );
+        });
+    });
+
+    document(w, cx, it, None, HeadingOffset::H2);
+
+    render_assoc_items(w, cx, it, it.item_id.expect_def_id(), AssocItemRender::All)
+}
+
+fn item_keyword(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item) {
+    document(w, cx, it, None, HeadingOffset::H2)
+}
+
+/// Compare two strings treating multi-digit numbers as single units (i.e. natural sort order).
+pub(crate) fn compare_names(mut lhs: &str, mut rhs: &str) -> Ordering {
+    /// Takes a non-numeric and a numeric part from the given &str.
+    fn take_parts<'a>(s: &mut &'a str) -> (&'a str, &'a str) {
+        let i = s.find(|c: char| c.is_ascii_digit());
+        let (a, b) = s.split_at(i.unwrap_or(s.len()));
+        let i = b.find(|c: char| !c.is_ascii_digit());
+        let (b, c) = b.split_at(i.unwrap_or(b.len()));
+        *s = c;
+        (a, b)
+    }
+
+    while !lhs.is_empty() || !rhs.is_empty() {
+        let (la, lb) = take_parts(&mut lhs);
+        let (ra, rb) = take_parts(&mut rhs);
+        // First process the non-numeric part.
+        match la.cmp(ra) {
+            Ordering::Equal => (),
+            x => return x,
+        }
+        // Then process the numeric part, if both sides have one (and they fit in a u64).
+        if let (Ok(ln), Ok(rn)) = (lb.parse::(), rb.parse::()) {
+            match ln.cmp(&rn) {
+                Ordering::Equal => (),
+                x => return x,
+            }
+        }
+        // Then process the numeric part again, but this time as strings.
+        match lb.cmp(rb) {
+            Ordering::Equal => (),
+            x => return x,
+        }
+    }
+
+    Ordering::Equal
+}
+
+pub(super) fn full_path(cx: &Context<'_>, item: &clean::Item) -> String {
+    let mut s = join_with_double_colon(&cx.current);
+    s.push_str("::");
+    s.push_str(item.name.unwrap().as_str());
+    s
+}
+
+pub(super) fn item_path(ty: ItemType, name: &str) -> String {
+    match ty {
+        ItemType::Module => format!("{}index.html", ensure_trailing_slash(name)),
+        _ => format!("{}.{}.html", ty, name),
+    }
+}
+
+fn bounds(t_bounds: &[clean::GenericBound], trait_alias: bool, cx: &Context<'_>) -> String {
+    let mut bounds = String::new();
+    if !t_bounds.is_empty() {
+        if !trait_alias {
+            bounds.push_str(": ");
+        }
+        for (i, p) in t_bounds.iter().enumerate() {
+            if i > 0 {
+                bounds.push_str(" + ");
+            }
+            bounds.push_str(&p.print(cx).to_string());
+        }
+    }
+    bounds
+}
+
+fn wrap_into_docblock(w: &mut Buffer, f: F)
+where
+    F: FnOnce(&mut Buffer),
+{
+    w.write_str("
    ");
+    f(w);
+    w.write_str("
    ")
+}
+
+fn wrap_item(w: &mut Buffer, item_name: &str, f: F)
+where
+    F: FnOnce(&mut Buffer),
+{
+    w.write_fmt(format_args!("
    ", item_name));
+    f(w);
+    w.write_str("
    ");
+}
+
+fn render_stability_since(
+    w: &mut Buffer,
+    item: &clean::Item,
+    containing_item: &clean::Item,
+    tcx: TyCtxt<'_>,
+) -> bool {
+    render_stability_since_raw(
+        w,
+        item.stable_since(tcx),
+        item.const_stability(tcx),
+        containing_item.stable_since(tcx),
+        containing_item.const_stable_since(tcx),
+    )
+}
+
+fn compare_impl<'a, 'b>(lhs: &'a &&Impl, rhs: &'b &&Impl, cx: &Context<'_>) -> Ordering {
+    let lhss = format!("{}", lhs.inner_impl().print(false, cx));
+    let rhss = format!("{}", rhs.inner_impl().print(false, cx));
+
+    // lhs and rhs are formatted as HTML, which may be unnecessary
+    compare_names(&lhss, &rhss)
+}
+
+fn render_implementor(
+    cx: &mut Context<'_>,
+    implementor: &Impl,
+    trait_: &clean::Item,
+    w: &mut Buffer,
+    implementor_dups: &FxHashMap,
+    aliases: &[String],
+) {
+    // If there's already another implementor that has the same abridged name, use the
+    // full path, for example in `std::iter::ExactSizeIterator`
+    let use_absolute = match implementor.inner_impl().for_ {
+        clean::Type::Path { ref path, .. }
+        | clean::BorrowedRef { type_: box clean::Type::Path { ref path, .. }, .. }
+            if !path.is_assoc_ty() =>
+        {
+            implementor_dups[&path.last()].1
+        }
+        _ => false,
+    };
+    render_impl(
+        w,
+        cx,
+        implementor,
+        trait_,
+        AssocItemLink::Anchor(None),
+        RenderMode::Normal,
+        Some(use_absolute),
+        aliases,
+        ImplRenderingParameters {
+            show_def_docs: false,
+            show_default_items: false,
+            show_non_assoc_items: false,
+            toggle_open_by_default: false,
+        },
+    );
+}
+
+fn render_union(
+    w: &mut Buffer,
+    it: &clean::Item,
+    g: Option<&clean::Generics>,
+    fields: &[clean::Item],
+    tab: &str,
+    cx: &Context<'_>,
+) {
+    write!(w, "{}union {}", it.visibility.print_with_space(it.item_id, cx), it.name.unwrap(),);
+
+    let where_displayed = g
+        .map(|g| {
+            write!(w, "{}", g.print(cx));
+            print_where_clause_and_check(w, g, cx)
+        })
+        .unwrap_or(false);
+
+    // If there wasn't a `where` clause, we add a whitespace.
+    if !where_displayed {
+        w.write_str(" ");
+    }
+
+    write!(w, "{{\n{}", tab);
+    let count_fields =
+        fields.iter().filter(|f| matches!(*f.kind, clean::StructFieldItem(..))).count();
+    let toggle = should_hide_fields(count_fields);
+    if toggle {
+        toggle_open(w, format_args!("{} fields", count_fields));
+    }
+
+    for field in fields {
+        if let clean::StructFieldItem(ref ty) = *field.kind {
+            write!(
+                w,
+                "    {}{}: {},\n{}",
+                field.visibility.print_with_space(field.item_id, cx),
+                field.name.unwrap(),
+                ty.print(cx),
+                tab
+            );
+        }
+    }
+
+    if it.has_stripped_entries().unwrap() {
+        write!(w, "    /* private fields */\n{}", tab);
+    }
+    if toggle {
+        toggle_close(w);
+    }
+    w.write_str("}");
+}
+
+fn render_struct(
+    w: &mut Buffer,
+    it: &clean::Item,
+    g: Option<&clean::Generics>,
+    ty: CtorKind,
+    fields: &[clean::Item],
+    tab: &str,
+    structhead: bool,
+    cx: &Context<'_>,
+) {
+    write!(
+        w,
+        "{}{}{}",
+        it.visibility.print_with_space(it.item_id, cx),
+        if structhead { "struct " } else { "" },
+        it.name.unwrap()
+    );
+    if let Some(g) = g {
+        write!(w, "{}", g.print(cx))
+    }
+    match ty {
+        CtorKind::Fictive => {
+            let where_diplayed = g.map(|g| print_where_clause_and_check(w, g, cx)).unwrap_or(false);
+
+            // If there wasn't a `where` clause, we add a whitespace.
+            if !where_diplayed {
+                w.write_str(" {");
+            } else {
+                w.write_str("{");
+            }
+            let count_fields =
+                fields.iter().filter(|f| matches!(*f.kind, clean::StructFieldItem(..))).count();
+            let has_visible_fields = count_fields > 0;
+            let toggle = should_hide_fields(count_fields);
+            if toggle {
+                toggle_open(w, format_args!("{} fields", count_fields));
+            }
+            for field in fields {
+                if let clean::StructFieldItem(ref ty) = *field.kind {
+                    write!(
+                        w,
+                        "\n{}    {}{}: {},",
+                        tab,
+                        field.visibility.print_with_space(field.item_id, cx),
+                        field.name.unwrap(),
+                        ty.print(cx),
+                    );
+                }
+            }
+
+            if has_visible_fields {
+                if it.has_stripped_entries().unwrap() {
+                    write!(w, "\n{}    /* private fields */", tab);
+                }
+                write!(w, "\n{}", tab);
+            } else if it.has_stripped_entries().unwrap() {
+                write!(w, " /* private fields */ ");
+            }
+            if toggle {
+                toggle_close(w);
+            }
+            w.write_str("}");
+        }
+        CtorKind::Fn => {
+            w.write_str("(");
+            for (i, field) in fields.iter().enumerate() {
+                if i > 0 {
+                    w.write_str(", ");
+                }
+                match *field.kind {
+                    clean::StrippedItem(box clean::StructFieldItem(..)) => write!(w, "_"),
+                    clean::StructFieldItem(ref ty) => {
+                        write!(
+                            w,
+                            "{}{}",
+                            field.visibility.print_with_space(field.item_id, cx),
+                            ty.print(cx),
+                        )
+                    }
+                    _ => unreachable!(),
+                }
+            }
+            w.write_str(")");
+            if let Some(g) = g {
+                write!(w, "{}", print_where_clause(g, cx, 0, Ending::NoNewline));
+            }
+            // We only want a ";" when we are displaying a tuple struct, not a variant tuple struct.
+            if structhead {
+                w.write_str(";");
+            }
+        }
+        CtorKind::Const => {
+            // Needed for PhantomData.
+            if let Some(g) = g {
+                write!(w, "{}", print_where_clause(g, cx, 0, Ending::NoNewline));
+            }
+            w.write_str(";");
+        }
+    }
+}
+
+fn document_non_exhaustive_header(item: &clean::Item) -> &str {
+    if item.is_non_exhaustive() { " (Non-exhaustive)" } else { "" }
+}
+
+fn document_non_exhaustive(w: &mut Buffer, item: &clean::Item) {
+    if item.is_non_exhaustive() {
+        write!(
+            w,
+            "
    \
+                 {}\
+                 
    ",
+            {
+                if item.is_struct() {
+                    "This struct is marked as non-exhaustive"
+                } else if item.is_enum() {
+                    "This enum is marked as non-exhaustive"
+                } else if item.is_variant() {
+                    "This variant is marked as non-exhaustive"
+                } else {
+                    "This type is marked as non-exhaustive"
+                }
+            }
+        );
+
+        if item.is_struct() {
+            w.write_str(
+                "Non-exhaustive structs could have additional fields added in future. \
+                 Therefore, non-exhaustive structs cannot be constructed in external crates \
+                 using the traditional Struct { .. } syntax; cannot be \
+                 matched against without a wildcard ..; and \
+                 struct update syntax will not work.",
+            );
+        } else if item.is_enum() {
+            w.write_str(
+                "Non-exhaustive enums could have additional variants added in future. \
+                 Therefore, when matching against variants of non-exhaustive enums, an \
+                 extra wildcard arm must be added to account for any future variants.",
+            );
+        } else if item.is_variant() {
+            w.write_str(
+                "Non-exhaustive enum variants could have additional fields added in future. \
+                 Therefore, non-exhaustive enum variants cannot be constructed in external \
+                 crates and cannot be matched against.",
+            );
+        } else {
+            w.write_str(
+                "This type will require a wildcard arm in any match statements or constructors.",
+            );
+        }
+
+        w.write_str("
    ");
+    }
+}
+
+fn document_type_layout(w: &mut Buffer, cx: &Context<'_>, ty_def_id: DefId) {
+    fn write_size_of_layout(w: &mut Buffer, layout: Layout<'_>, tag_size: u64) {
+        if layout.abi().is_unsized() {
+            write!(w, "(unsized)");
+        } else {
+            let bytes = layout.size().bytes() - tag_size;
+            write!(w, "{size} byte{pl}", size = bytes, pl = if bytes == 1 { "" } else { "s" },);
+        }
+    }
+
+    if !cx.shared.show_type_layout {
+        return;
+    }
+
+    writeln!(
+        w,
+        "
     \
+        Layout
    "
+    );
+    writeln!(w, "
    ");
+
+    let tcx = cx.tcx();
+    let param_env = tcx.param_env(ty_def_id);
+    let ty = tcx.type_of(ty_def_id);
+    match tcx.layout_of(param_env.and(ty)) {
+        Ok(ty_layout) => {
+            writeln!(
+                w,
+                "
    Note: Most layout information is \
+                 completely unstable and may even differ between compilations. \
+                 The only exception is types with certain repr(...) attributes. \
+                 Please see the Rust Reference’s \
+                 “Type Layout” \
+                 chapter for details on type layout guarantees.
    "
+            );
+            w.write_str("
    Size: ");
+            write_size_of_layout(w, ty_layout.layout, 0);
+            writeln!(w, "
    ");
+            if let Variants::Multiple { variants, tag, tag_encoding, .. } =
+                &ty_layout.layout.variants()
+            {
+                if !variants.is_empty() {
+                    w.write_str(
+                        "
    Size for each variant:
    \
+                            
      ",
+                    );
+
+                    let Adt(adt, _) = ty_layout.ty.kind() else {
+                        span_bug!(tcx.def_span(ty_def_id), "not an adt")
+                    };
+
+                    let tag_size = if let TagEncoding::Niche { .. } = tag_encoding {
+                        0
+                    } else if let Primitive::Int(i, _) = tag.primitive() {
+                        i.size().bytes()
+                    } else {
+                        span_bug!(tcx.def_span(ty_def_id), "tag is neither niche nor int")
+                    };
+
+                    for (index, layout) in variants.iter_enumerated() {
+                        let name = adt.variant(index).name;
+                        write!(w, "
    • {name}: ", name = name);
+                        write_size_of_layout(w, *layout, tag_size);
+                        writeln!(w, "
      • ");
+                    }
+                    w.write_str("
    ");
+                }
+            }
+        }
+        // This kind of layout error can occur with valid code, e.g. if you try to
+        // get the layout of a generic type such as `Vec`.
+        Err(LayoutError::Unknown(_)) => {
+            writeln!(
+                w,
+                "
    Note: Unable to compute type layout, \
+                 possibly due to this type having generic parameters. \
+                 Layout can only be computed for concrete, fully-instantiated types.
    "
+            );
+        }
+        // This kind of error probably can't happen with valid code, but we don't
+        // want to panic and prevent the docs from building, so we just let the
+        // user know that we couldn't compute the layout.
+        Err(LayoutError::SizeOverflow(_)) => {
+            writeln!(
+                w,
+                "
    Note: Encountered an error during type layout; \
+                 the type was too big.
    "
+            );
+        }
+        Err(LayoutError::NormalizationFailure(_, _)) => {
+            writeln!(
+                w,
+                "
    Note: Encountered an error during type layout; \
+                the type failed to be normalized.
    "
+            )
+        }
+    }
+
+    writeln!(w, "
    ");
+}
+
+fn pluralize(count: usize) -> &'static str {
+    if count > 1 { "s" } else { "" }
+}
diff --git a/src/librustdoc/html/render/search_index.rs b/src/librustdoc/html/render/search_index.rs
new file mode 100644
index 000000000..d672f0bb5
--- /dev/null
+++ b/src/librustdoc/html/render/search_index.rs
@@ -0,0 +1,589 @@
+use std::collections::hash_map::Entry;
+use std::collections::BTreeMap;
+
+use rustc_data_structures::fx::FxHashMap;
+use rustc_middle::ty::TyCtxt;
+use rustc_span::def_id::LOCAL_CRATE;
+use rustc_span::symbol::Symbol;
+use serde::ser::{Serialize, SerializeStruct, Serializer};
+
+use crate::clean;
+use crate::clean::types::{
+    FnRetTy, Function, GenericBound, Generics, ItemId, Type, WherePredicate,
+};
+use crate::formats::cache::{Cache, OrphanImplItem};
+use crate::formats::item_type::ItemType;
+use crate::html::format::join_with_double_colon;
+use crate::html::markdown::short_markdown_summary;
+use crate::html::render::{IndexItem, IndexItemFunctionType, RenderType, RenderTypeId};
+
+/// Builds the search index from the collected metadata
+pub(crate) fn build_index<'tcx>(
+    krate: &clean::Crate,
+    cache: &mut Cache,
+    tcx: TyCtxt<'tcx>,
+) -> String {
+    let mut itemid_to_pathid = FxHashMap::default();
+    let mut crate_paths = vec![];
+
+    // Attach all orphan items to the type's definition if the type
+    // has since been learned.
+    for &OrphanImplItem { parent, ref item, ref impl_generics } in &cache.orphan_impl_items {
+        if let Some(&(ref fqp, _)) = cache.paths.get(&parent) {
+            let desc = item
+                .doc_value()
+                .map_or_else(String::new, |s| short_markdown_summary(&s, &item.link_names(cache)));
+            cache.search_index.push(IndexItem {
+                ty: item.type_(),
+                name: item.name.unwrap().to_string(),
+                path: join_with_double_colon(&fqp[..fqp.len() - 1]),
+                desc,
+                parent: Some(parent),
+                parent_idx: None,
+                search_type: get_function_type_for_search(item, tcx, impl_generics.as_ref(), cache),
+                aliases: item.attrs.get_doc_aliases(),
+            });
+        }
+    }
+
+    let crate_doc = krate
+        .module
+        .doc_value()
+        .map_or_else(String::new, |s| short_markdown_summary(&s, &krate.module.link_names(cache)));
+
+    // Aliases added through `#[doc(alias = "...")]`. Since a few items can have the same alias,
+    // we need the alias element to have an array of items.
+    let mut aliases: BTreeMap> = BTreeMap::new();
+
+    // Sort search index items. This improves the compressibility of the search index.
+    cache.search_index.sort_unstable_by(|k1, k2| {
+        // `sort_unstable_by_key` produces lifetime errors
+        let k1 = (&k1.path, &k1.name, &k1.ty, &k1.parent);
+        let k2 = (&k2.path, &k2.name, &k2.ty, &k2.parent);
+        std::cmp::Ord::cmp(&k1, &k2)
+    });
+
+    // Set up alias indexes.
+    for (i, item) in cache.search_index.iter().enumerate() {
+        for alias in &item.aliases[..] {
+            aliases.entry(alias.as_str().to_lowercase()).or_default().push(i);
+        }
+    }
+
+    // Reduce `DefId` in paths into smaller sequential numbers,
+    // and prune the paths that do not appear in the index.
+    let mut lastpath = "";
+    let mut lastpathid = 0usize;
+
+    // First, on function signatures
+    let mut search_index = std::mem::replace(&mut cache.search_index, Vec::new());
+    for item in search_index.iter_mut() {
+        fn convert_render_type(
+            ty: &mut RenderType,
+            cache: &mut Cache,
+            itemid_to_pathid: &mut FxHashMap,
+            lastpathid: &mut usize,
+            crate_paths: &mut Vec<(ItemType, Symbol)>,
+        ) {
+            if let Some(generics) = &mut ty.generics {
+                for item in generics {
+                    convert_render_type(item, cache, itemid_to_pathid, lastpathid, crate_paths);
+                }
+            }
+            let Cache { ref paths, ref external_paths, .. } = *cache;
+            let Some(id) = ty.id.clone() else {
+                assert!(ty.generics.is_some());
+                return;
+            };
+            let (itemid, path, item_type) = match id {
+                RenderTypeId::DefId(defid) => {
+                    if let Some(&(ref fqp, item_type)) =
+                        paths.get(&defid).or_else(|| external_paths.get(&defid))
+                    {
+                        (ItemId::DefId(defid), *fqp.last().unwrap(), item_type)
+                    } else {
+                        ty.id = None;
+                        return;
+                    }
+                }
+                RenderTypeId::Primitive(primitive) => (
+                    ItemId::Primitive(primitive, LOCAL_CRATE),
+                    primitive.as_sym(),
+                    ItemType::Primitive,
+                ),
+                RenderTypeId::Index(_) => return,
+            };
+            match itemid_to_pathid.entry(itemid) {
+                Entry::Occupied(entry) => ty.id = Some(RenderTypeId::Index(*entry.get())),
+                Entry::Vacant(entry) => {
+                    let pathid = *lastpathid;
+                    entry.insert(pathid);
+                    *lastpathid += 1;
+                    crate_paths.push((item_type, path));
+                    ty.id = Some(RenderTypeId::Index(pathid));
+                }
+            }
+        }
+        if let Some(search_type) = &mut item.search_type {
+            for item in &mut search_type.inputs {
+                convert_render_type(
+                    item,
+                    cache,
+                    &mut itemid_to_pathid,
+                    &mut lastpathid,
+                    &mut crate_paths,
+                );
+            }
+            for item in &mut search_type.output {
+                convert_render_type(
+                    item,
+                    cache,
+                    &mut itemid_to_pathid,
+                    &mut lastpathid,
+                    &mut crate_paths,
+                );
+            }
+        }
+    }
+
+    let Cache { ref paths, .. } = *cache;
+
+    // Then, on parent modules
+    let crate_items: Vec<&IndexItem> = search_index
+        .iter_mut()
+        .map(|item| {
+            item.parent_idx =
+                item.parent.and_then(|defid| match itemid_to_pathid.entry(ItemId::DefId(defid)) {
+                    Entry::Occupied(entry) => Some(*entry.get()),
+                    Entry::Vacant(entry) => {
+                        let pathid = lastpathid;
+                        entry.insert(pathid);
+                        lastpathid += 1;
+
+                        if let Some(&(ref fqp, short)) = paths.get(&defid) {
+                            crate_paths.push((short, *fqp.last().unwrap()));
+                            Some(pathid)
+                        } else {
+                            None
+                        }
+                    }
+                });
+
+            // Omit the parent path if it is same to that of the prior item.
+            if lastpath == &item.path {
+                item.path.clear();
+            } else {
+                lastpath = &item.path;
+            }
+
+            &*item
+        })
+        .collect();
+
+    struct CrateData<'a> {
+        doc: String,
+        items: Vec<&'a IndexItem>,
+        paths: Vec<(ItemType, Symbol)>,
+        // The String is alias name and the vec is the list of the elements with this alias.
+        //
+        // To be noted: the `usize` elements are indexes to `items`.
+        aliases: &'a BTreeMap>,
+    }
+
+    impl<'a> Serialize for CrateData<'a> {
+        fn serialize(&self, serializer: S) -> Result
+        where
+            S: Serializer,
+        {
+            let has_aliases = !self.aliases.is_empty();
+            let mut crate_data =
+                serializer.serialize_struct("CrateData", if has_aliases { 9 } else { 8 })?;
+            crate_data.serialize_field("doc", &self.doc)?;
+            crate_data.serialize_field(
+                "t",
+                &self.items.iter().map(|item| &item.ty).collect::>(),
+            )?;
+            crate_data.serialize_field(
+                "n",
+                &self.items.iter().map(|item| &item.name).collect::>(),
+            )?;
+            crate_data.serialize_field(
+                "q",
+                &self.items.iter().map(|item| &item.path).collect::>(),
+            )?;
+            crate_data.serialize_field(
+                "d",
+                &self.items.iter().map(|item| &item.desc).collect::>(),
+            )?;
+            crate_data.serialize_field(
+                "i",
+                &self
+                    .items
+                    .iter()
+                    .map(|item| {
+                        assert_eq!(
+                            item.parent.is_some(),
+                            item.parent_idx.is_some(),
+                            "`{}` is missing idx",
+                            item.name
+                        );
+                        // 0 is a sentinel, everything else is one-indexed
+                        item.parent_idx.map(|x| x + 1).unwrap_or(0)
+                    })
+                    .collect::>(),
+            )?;
+            crate_data.serialize_field(
+                "f",
+                &self
+                    .items
+                    .iter()
+                    .map(|item| {
+                        // Fake option to get `0` out as a sentinel instead of `null`.
+                        // We want to use `0` because it's three less bytes.
+                        enum FunctionOption<'a> {
+                            Function(&'a IndexItemFunctionType),
+                            None,
+                        }
+                        impl<'a> Serialize for FunctionOption<'a> {
+                            fn serialize(&self, serializer: S) -> Result
+                            where
+                                S: Serializer,
+                            {
+                                match self {
+                                    FunctionOption::None => 0.serialize(serializer),
+                                    FunctionOption::Function(ty) => ty.serialize(serializer),
+                                }
+                            }
+                        }
+                        match &item.search_type {
+                            Some(ty) => FunctionOption::Function(ty),
+                            None => FunctionOption::None,
+                        }
+                    })
+                    .collect::>(),
+            )?;
+            crate_data.serialize_field(
+                "p",
+                &self.paths.iter().map(|(it, s)| (it, s.to_string())).collect::>(),
+            )?;
+            if has_aliases {
+                crate_data.serialize_field("a", &self.aliases)?;
+            }
+            crate_data.end()
+        }
+    }
+
+    // Collect the index into a string
+    format!(
+        r#""{}":{}"#,
+        krate.name(tcx),
+        serde_json::to_string(&CrateData {
+            doc: crate_doc,
+            items: crate_items,
+            paths: crate_paths,
+            aliases: &aliases,
+        })
+        .expect("failed serde conversion")
+        // All these `replace` calls are because we have to go through JS string for JSON content.
+        .replace('\\', r"\\")
+        .replace('\'', r"\'")
+        // We need to escape double quotes for the JSON.
+        .replace("\\\"", "\\\\\"")
+    )
+}
+
+pub(crate) fn get_function_type_for_search<'tcx>(
+    item: &clean::Item,
+    tcx: TyCtxt<'tcx>,
+    impl_generics: Option<&(clean::Type, clean::Generics)>,
+    cache: &Cache,
+) -> Option {
+    let (mut inputs, mut output) = match *item.kind {
+        clean::FunctionItem(ref f) => get_fn_inputs_and_outputs(f, tcx, impl_generics, cache),
+        clean::MethodItem(ref m, _) => get_fn_inputs_and_outputs(m, tcx, impl_generics, cache),
+        clean::TyMethodItem(ref m) => get_fn_inputs_and_outputs(m, tcx, impl_generics, cache),
+        _ => return None,
+    };
+
+    inputs.retain(|a| a.id.is_some() || a.generics.is_some());
+    output.retain(|a| a.id.is_some() || a.generics.is_some());
+
+    Some(IndexItemFunctionType { inputs, output })
+}
+
+fn get_index_type(clean_type: &clean::Type, generics: Vec) -> RenderType {
+    RenderType {
+        id: get_index_type_id(clean_type),
+        generics: if generics.is_empty() { None } else { Some(generics) },
+    }
+}
+
+fn get_index_type_id(clean_type: &clean::Type) -> Option {
+    match *clean_type {
+        clean::Type::Path { ref path, .. } => Some(RenderTypeId::DefId(path.def_id())),
+        clean::DynTrait(ref bounds, _) => {
+            let path = &bounds[0].trait_;
+            Some(RenderTypeId::DefId(path.def_id()))
+        }
+        clean::Primitive(p) => Some(RenderTypeId::Primitive(p)),
+        clean::BorrowedRef { ref type_, .. } | clean::RawPointer(_, ref type_) => {
+            get_index_type_id(type_)
+        }
+        clean::BareFunction(_)
+        | clean::Generic(_)
+        | clean::ImplTrait(_)
+        | clean::Tuple(_)
+        | clean::Slice(_)
+        | clean::Array(_, _)
+        | clean::QPath { .. }
+        | clean::Infer => None,
+    }
+}
+
+/// The point of this function is to replace bounds with types.
+///
+/// i.e. `[T, U]` when you have the following bounds: `T: Display, U: Option` will return
+/// `[Display, Option]`. If a type parameter has no trait bound, it is discarded.
+///
+/// Important note: It goes through generics recursively. So if you have
+/// `T: Option>`, it'll go into `Option` and then into `Result`.
+#[instrument(level = "trace", skip(tcx, res, cache))]
+fn add_generics_and_bounds_as_types<'tcx, 'a>(
+    self_: Option<&'a Type>,
+    generics: &Generics,
+    arg: &'a Type,
+    tcx: TyCtxt<'tcx>,
+    recurse: usize,
+    res: &mut Vec,
+    cache: &Cache,
+) {
+    fn insert_ty(res: &mut Vec, ty: Type, mut generics: Vec) {
+        // generics and impl trait are both identified by their generics,
+        // rather than a type name itself
+        let anonymous = ty.is_full_generic() || ty.is_impl_trait();
+        let generics_empty = generics.is_empty();
+
+        if anonymous {
+            if generics_empty {
+                // This is a type parameter with no trait bounds (for example: `T` in
+                // `fn f(p: T)`, so not useful for the rustdoc search because we would end up
+                // with an empty type with an empty name. Let's just discard it.
+                return;
+            } else if generics.len() == 1 {
+                // In this case, no need to go through an intermediate state if the type parameter
+                // contains only one trait bound.
+                //
+                // For example:
+                //
+                // `fn foo(r: Option) {}`
+                //
+                // In this case, it would contain:
+                //
+                // ```
+                // [{
+                //     name: "option",
+                //     generics: [{
+                //         name: "",
+                //         generics: [
+                //             name: "Display",
+                //             generics: []
+                //         }]
+                //     }]
+                // }]
+                // ```
+                //
+                // After removing the intermediate (unnecessary) type parameter, it'll become:
+                //
+                // ```
+                // [{
+                //     name: "option",
+                //     generics: [{
+                //         name: "Display",
+                //         generics: []
+                //     }]
+                // }]
+                // ```
+                //
+                // To be noted that it can work if there is ONLY ONE trait bound, otherwise we still
+                // need to keep it as is!
+                res.push(generics.pop().unwrap());
+                return;
+            }
+        }
+        let index_ty = get_index_type(&ty, generics);
+        if index_ty.id.is_none() && generics_empty {
+            return;
+        }
+        res.push(index_ty);
+    }
+
+    if recurse >= 10 {
+        // FIXME: remove this whole recurse thing when the recursion bug is fixed
+        // See #59502 for the original issue.
+        return;
+    }
+
+    // First, check if it's "Self".
+    let arg = if let Some(self_) = self_ {
+        match &*arg {
+            Type::BorrowedRef { type_, .. } if type_.is_self_type() => self_,
+            type_ if type_.is_self_type() => self_,
+            arg => arg,
+        }
+    } else {
+        arg
+    };
+
+    // If this argument is a type parameter and not a trait bound or a type, we need to look
+    // for its bounds.
+    if let Type::Generic(arg_s) = *arg {
+        // First we check if the bounds are in a `where` predicate...
+        if let Some(where_pred) = generics.where_predicates.iter().find(|g| match g {
+            WherePredicate::BoundPredicate { ty, .. } => ty.def_id(cache) == arg.def_id(cache),
+            _ => false,
+        }) {
+            let mut ty_generics = Vec::new();
+            let bounds = where_pred.get_bounds().unwrap_or_else(|| &[]);
+            for bound in bounds.iter() {
+                if let GenericBound::TraitBound(poly_trait, _) = bound {
+                    for param_def in poly_trait.generic_params.iter() {
+                        match ¶m_def.kind {
+                            clean::GenericParamDefKind::Type { default: Some(ty), .. } => {
+                                add_generics_and_bounds_as_types(
+                                    self_,
+                                    generics,
+                                    ty,
+                                    tcx,
+                                    recurse + 1,
+                                    &mut ty_generics,
+                                    cache,
+                                )
+                            }
+                            _ => {}
+                        }
+                    }
+                }
+            }
+            insert_ty(res, arg.clone(), ty_generics);
+        }
+        // Otherwise we check if the trait bounds are "inlined" like `T: Option`...
+        if let Some(bound) = generics.params.iter().find(|g| g.is_type() && g.name == arg_s) {
+            let mut ty_generics = Vec::new();
+            for bound in bound.get_bounds().unwrap_or(&[]) {
+                if let Some(path) = bound.get_trait_path() {
+                    let ty = Type::Path { path };
+                    add_generics_and_bounds_as_types(
+                        self_,
+                        generics,
+                        &ty,
+                        tcx,
+                        recurse + 1,
+                        &mut ty_generics,
+                        cache,
+                    );
+                }
+            }
+            insert_ty(res, arg.clone(), ty_generics);
+        }
+    } else if let Type::ImplTrait(ref bounds) = *arg {
+        let mut ty_generics = Vec::new();
+        for bound in bounds {
+            if let Some(path) = bound.get_trait_path() {
+                let ty = Type::Path { path };
+                add_generics_and_bounds_as_types(
+                    self_,
+                    generics,
+                    &ty,
+                    tcx,
+                    recurse + 1,
+                    &mut ty_generics,
+                    cache,
+                );
+            }
+        }
+        insert_ty(res, arg.clone(), ty_generics);
+    } else {
+        // This is not a type parameter. So for example if we have `T, U: Option`, and we're
+        // looking at `Option`, we enter this "else" condition, otherwise if it's `T`, we don't.
+        //
+        // So in here, we can add it directly and look for its own type parameters (so for `Option`,
+        // we will look for them but not for `T`).
+        let mut ty_generics = Vec::new();
+        if let Some(arg_generics) = arg.generics() {
+            for gen in arg_generics.iter() {
+                add_generics_and_bounds_as_types(
+                    self_,
+                    generics,
+                    gen,
+                    tcx,
+                    recurse + 1,
+                    &mut ty_generics,
+                    cache,
+                );
+            }
+        }
+        insert_ty(res, arg.clone(), ty_generics);
+    }
+}
+
+/// Return the full list of types when bounds have been resolved.
+///
+/// i.e. `fn foo>(x: u32, y: B)` will return
+/// `[u32, Display, Option]`.
+fn get_fn_inputs_and_outputs<'tcx>(
+    func: &Function,
+    tcx: TyCtxt<'tcx>,
+    impl_generics: Option<&(clean::Type, clean::Generics)>,
+    cache: &Cache,
+) -> (Vec, Vec) {
+    let decl = &func.decl;
+
+    let combined_generics;
+    let (self_, generics) = if let Some(&(ref impl_self, ref impl_generics)) = impl_generics {
+        match (impl_generics.is_empty(), func.generics.is_empty()) {
+            (true, _) => (Some(impl_self), &func.generics),
+            (_, true) => (Some(impl_self), impl_generics),
+            (false, false) => {
+                let mut params = func.generics.params.clone();
+                params.extend(impl_generics.params.clone());
+                let mut where_predicates = func.generics.where_predicates.clone();
+                where_predicates.extend(impl_generics.where_predicates.clone());
+                combined_generics = clean::Generics { params, where_predicates };
+                (Some(impl_self), &combined_generics)
+            }
+        }
+    } else {
+        (None, &func.generics)
+    };
+
+    let mut all_types = Vec::new();
+    for arg in decl.inputs.values.iter() {
+        let mut args = Vec::new();
+        add_generics_and_bounds_as_types(self_, generics, &arg.type_, tcx, 0, &mut args, cache);
+        if !args.is_empty() {
+            all_types.extend(args);
+        } else {
+            all_types.push(get_index_type(&arg.type_, vec![]));
+        }
+    }
+
+    let mut ret_types = Vec::new();
+    match decl.output {
+        FnRetTy::Return(ref return_type) => {
+            add_generics_and_bounds_as_types(
+                self_,
+                generics,
+                return_type,
+                tcx,
+                0,
+                &mut ret_types,
+                cache,
+            );
+            if ret_types.is_empty() {
+                ret_types.push(get_index_type(return_type, vec![]));
+            }
+        }
+        _ => {}
+    };
+    (all_types, ret_types)
+}
diff --git a/src/librustdoc/html/render/span_map.rs b/src/librustdoc/html/render/span_map.rs
new file mode 100644
index 000000000..34d590fb2
--- /dev/null
+++ b/src/librustdoc/html/render/span_map.rs
@@ -0,0 +1,203 @@
+use crate::clean::{self, PrimitiveType};
+use crate::html::sources;
+
+use rustc_data_structures::fx::FxHashMap;
+use rustc_hir::def::{DefKind, Res};
+use rustc_hir::def_id::DefId;
+use rustc_hir::intravisit::{self, Visitor};
+use rustc_hir::{ExprKind, HirId, Mod, Node};
+use rustc_middle::hir::nested_filter;
+use rustc_middle::ty::TyCtxt;
+use rustc_span::hygiene::MacroKind;
+use rustc_span::{BytePos, ExpnKind, Span};
+
+use std::path::{Path, PathBuf};
+
+/// This enum allows us to store two different kinds of information:
+///
+/// In case the `span` definition comes from the same crate, we can simply get the `span` and use
+/// it as is.
+///
+/// Otherwise, we store the definition `DefId` and will generate a link to the documentation page
+/// instead of the source code directly.
+#[derive(Debug)]
+pub(crate) enum LinkFromSrc {
+    Local(clean::Span),
+    External(DefId),
+    Primitive(PrimitiveType),
+}
+
+/// This function will do at most two things:
+///
+/// 1. Generate a `span` correspondance map which links an item `span` to its definition `span`.
+/// 2. Collect the source code files.
+///
+/// It returns the `krate`, the source code files and the `span` correspondance map.
+///
+/// Note about the `span` correspondance map: the keys are actually `(lo, hi)` of `span`s. We don't
+/// need the `span` context later on, only their position, so instead of keep a whole `Span`, we
+/// only keep the `lo` and `hi`.
+pub(crate) fn collect_spans_and_sources(
+    tcx: TyCtxt<'_>,
+    krate: &clean::Crate,
+    src_root: &Path,
+    include_sources: bool,
+    generate_link_to_definition: bool,
+) -> (FxHashMap, FxHashMap) {
+    let mut visitor = SpanMapVisitor { tcx, matches: FxHashMap::default() };
+
+    if include_sources {
+        if generate_link_to_definition {
+            tcx.hir().walk_toplevel_module(&mut visitor);
+        }
+        let sources = sources::collect_local_sources(tcx, src_root, krate);
+        (sources, visitor.matches)
+    } else {
+        (Default::default(), Default::default())
+    }
+}
+
+struct SpanMapVisitor<'tcx> {
+    pub(crate) tcx: TyCtxt<'tcx>,
+    pub(crate) matches: FxHashMap,
+}
+
+impl<'tcx> SpanMapVisitor<'tcx> {
+    /// This function is where we handle `hir::Path` elements and add them into the "span map".
+    fn handle_path(&mut self, path: &rustc_hir::Path<'_>) {
+        let info = match path.res {
+            // FIXME: For now, we handle `DefKind` if it's not a `DefKind::TyParam`.
+            // Would be nice to support them too alongside the other `DefKind`
+            // (such as primitive types!).
+            Res::Def(kind, def_id) if kind != DefKind::TyParam => Some(def_id),
+            Res::Local(_) => None,
+            Res::PrimTy(p) => {
+                // FIXME: Doesn't handle "path-like" primitives like arrays or tuples.
+                self.matches.insert(path.span, LinkFromSrc::Primitive(PrimitiveType::from(p)));
+                return;
+            }
+            Res::Err => return,
+            _ => return,
+        };
+        if let Some(span) = self.tcx.hir().res_span(path.res) {
+            self.matches.insert(path.span, LinkFromSrc::Local(clean::Span::new(span)));
+        } else if let Some(def_id) = info {
+            self.matches.insert(path.span, LinkFromSrc::External(def_id));
+        }
+    }
+
+    /// Adds the macro call into the span map. Returns `true` if the `span` was inside a macro
+    /// expansion, whether or not it was added to the span map.
+    ///
+    /// The idea for the macro support is to check if the current `Span` comes from expansion. If
+    /// so, we loop until we find the macro definition by using `outer_expn_data` in a loop.
+    /// Finally, we get the information about the macro itself (`span` if "local", `DefId`
+    /// otherwise) and store it inside the span map.
+    fn handle_macro(&mut self, span: Span) -> bool {
+        if !span.from_expansion() {
+            return false;
+        }
+        // So if the `span` comes from a macro expansion, we need to get the original
+        // macro's `DefId`.
+        let mut data = span.ctxt().outer_expn_data();
+        let mut call_site = data.call_site;
+        // Macros can expand to code containing macros, which will in turn be expanded, etc.
+        // So the idea here is to "go up" until we're back to code that was generated from
+        // macro expansion so that we can get the `DefId` of the original macro that was at the
+        // origin of this expansion.
+        while call_site.from_expansion() {
+            data = call_site.ctxt().outer_expn_data();
+            call_site = data.call_site;
+        }
+
+        let macro_name = match data.kind {
+            ExpnKind::Macro(MacroKind::Bang, macro_name) => macro_name,
+            // Even though we don't handle this kind of macro, this `data` still comes from
+            // expansion so we return `true` so we don't go any deeper in this code.
+            _ => return true,
+        };
+        let link_from_src = match data.macro_def_id {
+            Some(macro_def_id) if macro_def_id.is_local() => {
+                LinkFromSrc::Local(clean::Span::new(data.def_site))
+            }
+            Some(macro_def_id) => LinkFromSrc::External(macro_def_id),
+            None => return true,
+        };
+        let new_span = data.call_site;
+        let macro_name = macro_name.as_str();
+        // The "call_site" includes the whole macro with its "arguments". We only want
+        // the macro name.
+        let new_span = new_span.with_hi(new_span.lo() + BytePos(macro_name.len() as u32));
+        self.matches.insert(new_span, link_from_src);
+        true
+    }
+}
+
+impl<'tcx> Visitor<'tcx> for SpanMapVisitor<'tcx> {
+    type NestedFilter = nested_filter::All;
+
+    fn nested_visit_map(&mut self) -> Self::Map {
+        self.tcx.hir()
+    }
+
+    fn visit_path(&mut self, path: &'tcx rustc_hir::Path<'tcx>, _id: HirId) {
+        if self.handle_macro(path.span) {
+            return;
+        }
+        self.handle_path(path);
+        intravisit::walk_path(self, path);
+    }
+
+    fn visit_mod(&mut self, m: &'tcx Mod<'tcx>, span: Span, id: HirId) {
+        // To make the difference between "mod foo {}" and "mod foo;". In case we "import" another
+        // file, we want to link to it. Otherwise no need to create a link.
+        if !span.overlaps(m.spans.inner_span) {
+            // Now that we confirmed it's a file import, we want to get the span for the module
+            // name only and not all the "mod foo;".
+            if let Some(Node::Item(item)) = self.tcx.hir().find(id) {
+                self.matches.insert(
+                    item.ident.span,
+                    LinkFromSrc::Local(clean::Span::new(m.spans.inner_span)),
+                );
+            }
+        }
+        intravisit::walk_mod(self, m, id);
+    }
+
+    fn visit_expr(&mut self, expr: &'tcx rustc_hir::Expr<'tcx>) {
+        if let ExprKind::MethodCall(segment, ..) = expr.kind {
+            if let Some(hir_id) = segment.hir_id {
+                let hir = self.tcx.hir();
+                let body_id = hir.enclosing_body_owner(hir_id);
+                // FIXME: this is showing error messages for parts of the code that are not
+                // compiled (because of cfg)!
+                //
+                // See discussion in https://github.com/rust-lang/rust/issues/69426#issuecomment-1019412352
+                let typeck_results = self.tcx.typeck_body(
+                    hir.maybe_body_owned_by(body_id).expect("a body which isn't a body"),
+                );
+                if let Some(def_id) = typeck_results.type_dependent_def_id(expr.hir_id) {
+                    self.matches.insert(
+                        segment.ident.span,
+                        match hir.span_if_local(def_id) {
+                            Some(span) => LinkFromSrc::Local(clean::Span::new(span)),
+                            None => LinkFromSrc::External(def_id),
+                        },
+                    );
+                }
+            }
+        } else if self.handle_macro(expr.span) {
+            // We don't want to go deeper into the macro.
+            return;
+        }
+        intravisit::walk_expr(self, expr);
+    }
+
+    fn visit_use(&mut self, path: &'tcx rustc_hir::Path<'tcx>, id: HirId) {
+        if self.handle_macro(path.span) {
+            return;
+        }
+        self.handle_path(path);
+        intravisit::walk_use(self, path, id);
+    }
+}
diff --git a/src/librustdoc/html/render/tests.rs b/src/librustdoc/html/render/tests.rs
new file mode 100644
index 000000000..3175fbe56
--- /dev/null
+++ b/src/librustdoc/html/render/tests.rs
@@ -0,0 +1,54 @@
+use std::cmp::Ordering;
+
+use super::print_item::compare_names;
+use super::{AllTypes, Buffer};
+
+#[test]
+fn test_compare_names() {
+    for &(a, b) in &[
+        ("hello", "world"),
+        ("", "world"),
+        ("123", "hello"),
+        ("123", ""),
+        ("123test", "123"),
+        ("hello", ""),
+        ("hello", "hello"),
+        ("hello123", "hello123"),
+        ("hello123", "hello12"),
+        ("hello12", "hello123"),
+        ("hello01abc", "hello01xyz"),
+        ("hello0abc", "hello0"),
+        ("hello0", "hello0abc"),
+        ("01", "1"),
+    ] {
+        assert_eq!(compare_names(a, b), a.cmp(b), "{:?} - {:?}", a, b);
+    }
+    assert_eq!(compare_names("u8", "u16"), Ordering::Less);
+    assert_eq!(compare_names("u32", "u16"), Ordering::Greater);
+    assert_eq!(compare_names("u8_to_f64", "u16_to_f64"), Ordering::Less);
+    assert_eq!(compare_names("u32_to_f64", "u16_to_f64"), Ordering::Greater);
+    assert_eq!(compare_names("u16_to_f64", "u16_to_f64"), Ordering::Equal);
+    assert_eq!(compare_names("u16_to_f32", "u16_to_f64"), Ordering::Less);
+}
+
+#[test]
+fn test_name_sorting() {
+    let names = [
+        "Apple", "Banana", "Fruit", "Fruit0", "Fruit00", "Fruit01", "Fruit1", "Fruit02", "Fruit2",
+        "Fruit20", "Fruit30x", "Fruit100", "Pear",
+    ];
+    let mut sorted = names.to_owned();
+    sorted.sort_by(|&l, r| compare_names(l, r));
+    assert_eq!(names, sorted);
+}
+
+#[test]
+fn test_all_types_prints_header_once() {
+    // Regression test for #82477
+    let all_types = AllTypes::new();
+
+    let mut buffer = Buffer::new();
+    all_types.print(&mut buffer);
+
+    assert_eq!(1, buffer.into_inner().matches("List of all items").count());
+}
diff --git a/src/librustdoc/html/render/write_shared.rs b/src/librustdoc/html/render/write_shared.rs
new file mode 100644
index 000000000..6fb41ff32
--- /dev/null
+++ b/src/librustdoc/html/render/write_shared.rs
@@ -0,0 +1,600 @@
+use std::ffi::OsStr;
+use std::fmt::Write;
+use std::fs::{self, File};
+use std::io::prelude::*;
+use std::io::{self, BufReader};
+use std::path::{Component, Path, PathBuf};
+use std::rc::Rc;
+use std::sync::LazyLock as Lazy;
+
+use itertools::Itertools;
+use rustc_data_structures::flock;
+use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use serde::Serialize;
+
+use super::{collect_paths_for_type, ensure_trailing_slash, Context, BASIC_KEYWORDS};
+use crate::clean::Crate;
+use crate::config::{EmitType, RenderOptions};
+use crate::docfs::PathError;
+use crate::error::Error;
+use crate::html::{layout, static_files};
+use crate::{try_err, try_none};
+
+static FILES_UNVERSIONED: Lazy> = Lazy::new(|| {
+    map! {
+        "FiraSans-Regular.woff2" => static_files::fira_sans::REGULAR,
+        "FiraSans-Medium.woff2" => static_files::fira_sans::MEDIUM,
+        "FiraSans-LICENSE.txt" => static_files::fira_sans::LICENSE,
+        "SourceSerif4-Regular.ttf.woff2" => static_files::source_serif_4::REGULAR,
+        "SourceSerif4-Bold.ttf.woff2" => static_files::source_serif_4::BOLD,
+        "SourceSerif4-It.ttf.woff2" => static_files::source_serif_4::ITALIC,
+        "SourceSerif4-LICENSE.md" => static_files::source_serif_4::LICENSE,
+        "SourceCodePro-Regular.ttf.woff2" => static_files::source_code_pro::REGULAR,
+        "SourceCodePro-Semibold.ttf.woff2" => static_files::source_code_pro::SEMIBOLD,
+        "SourceCodePro-It.ttf.woff2" => static_files::source_code_pro::ITALIC,
+        "SourceCodePro-LICENSE.txt" => static_files::source_code_pro::LICENSE,
+        "NanumBarunGothic.ttf.woff2" => static_files::nanum_barun_gothic::REGULAR,
+        "NanumBarunGothic-LICENSE.txt" => static_files::nanum_barun_gothic::LICENSE,
+        "LICENSE-MIT.txt" => static_files::LICENSE_MIT,
+        "LICENSE-APACHE.txt" => static_files::LICENSE_APACHE,
+        "COPYRIGHT.txt" => static_files::COPYRIGHT,
+    }
+});
+
+enum SharedResource<'a> {
+    /// This file will never change, no matter what toolchain is used to build it.
+    ///
+    /// It does not have a resource suffix.
+    Unversioned { name: &'static str },
+    /// This file may change depending on the toolchain.
+    ///
+    /// It has a resource suffix.
+    ToolchainSpecific { basename: &'static str },
+    /// This file may change for any crate within a build, or based on the CLI arguments.
+    ///
+    /// This differs from normal invocation-specific files because it has a resource suffix.
+    InvocationSpecific { basename: &'a str },
+}
+
+impl SharedResource<'_> {
+    fn extension(&self) -> Option<&OsStr> {
+        use SharedResource::*;
+        match self {
+            Unversioned { name }
+            | ToolchainSpecific { basename: name }
+            | InvocationSpecific { basename: name } => Path::new(name).extension(),
+        }
+    }
+
+    fn path(&self, cx: &Context<'_>) -> PathBuf {
+        match self {
+            SharedResource::Unversioned { name } => cx.dst.join(name),
+            SharedResource::ToolchainSpecific { basename } => cx.suffix_path(basename),
+            SharedResource::InvocationSpecific { basename } => cx.suffix_path(basename),
+        }
+    }
+
+    fn should_emit(&self, emit: &[EmitType]) -> bool {
+        if emit.is_empty() {
+            return true;
+        }
+        let kind = match self {
+            SharedResource::Unversioned { .. } => EmitType::Unversioned,
+            SharedResource::ToolchainSpecific { .. } => EmitType::Toolchain,
+            SharedResource::InvocationSpecific { .. } => EmitType::InvocationSpecific,
+        };
+        emit.contains(&kind)
+    }
+}
+
+impl Context<'_> {
+    fn suffix_path(&self, filename: &str) -> PathBuf {
+        // We use splitn vs Path::extension here because we might get a filename
+        // like `style.min.css` and we want to process that into
+        // `style-suffix.min.css`.  Path::extension would just return `css`
+        // which would result in `style.min-suffix.css` which isn't what we
+        // want.
+        let (base, ext) = filename.split_once('.').unwrap();
+        let filename = format!("{}{}.{}", base, self.shared.resource_suffix, ext);
+        self.dst.join(&filename)
+    }
+
+    fn write_shared(
+        &self,
+        resource: SharedResource<'_>,
+        contents: impl 'static + Send + AsRef<[u8]>,
+        emit: &[EmitType],
+    ) -> Result<(), Error> {
+        if resource.should_emit(emit) {
+            self.shared.fs.write(resource.path(self), contents)
+        } else {
+            Ok(())
+        }
+    }
+
+    fn write_minify(
+        &self,
+        resource: SharedResource<'_>,
+        contents: impl 'static + Send + AsRef + AsRef<[u8]>,
+        minify: bool,
+        emit: &[EmitType],
+    ) -> Result<(), Error> {
+        if minify {
+            let contents = contents.as_ref();
+            let contents = if resource.extension() == Some(OsStr::new("css")) {
+                minifier::css::minify(contents)
+                    .map_err(|e| {
+                        Error::new(format!("failed to minify CSS file: {}", e), resource.path(self))
+                    })?
+                    .to_string()
+            } else {
+                minifier::js::minify(contents).to_string()
+            };
+            self.write_shared(resource, contents, emit)
+        } else {
+            self.write_shared(resource, contents, emit)
+        }
+    }
+}
+
+pub(super) fn write_shared(
+    cx: &mut Context<'_>,
+    krate: &Crate,
+    search_index: String,
+    options: &RenderOptions,
+) -> Result<(), Error> {
+    // Write out the shared files. Note that these are shared among all rustdoc
+    // docs placed in the output directory, so this needs to be a synchronized
+    // operation with respect to all other rustdocs running around.
+    let lock_file = cx.dst.join(".lock");
+    let _lock = try_err!(flock::Lock::new(&lock_file, true, true, true), &lock_file);
+
+    // Minified resources are usually toolchain resources. If they're not, they should use `cx.write_minify` directly.
+    fn write_minify(
+        basename: &'static str,
+        contents: impl 'static + Send + AsRef + AsRef<[u8]>,
+        cx: &Context<'_>,
+        options: &RenderOptions,
+    ) -> Result<(), Error> {
+        cx.write_minify(
+            SharedResource::ToolchainSpecific { basename },
+            contents,
+            options.enable_minification,
+            &options.emit,
+        )
+    }
+
+    // Toolchain resources should never be dynamic.
+    let write_toolchain = |p: &'static _, c: &'static _| {
+        cx.write_shared(SharedResource::ToolchainSpecific { basename: p }, c, &options.emit)
+    };
+
+    // Crate resources should always be dynamic.
+    let write_crate = |p: &_, make_content: &dyn Fn() -> Result, Error>| {
+        let content = make_content()?;
+        cx.write_shared(SharedResource::InvocationSpecific { basename: p }, content, &options.emit)
+    };
+
+    // Given "foo.svg", return e.g. "url(\"foo1.58.0.svg\")"
+    fn ver_url(cx: &Context<'_>, basename: &'static str) -> String {
+        format!(
+            "url(\"{}\")",
+            SharedResource::ToolchainSpecific { basename }
+                .path(cx)
+                .file_name()
+                .unwrap()
+                .to_str()
+                .unwrap()
+        )
+    }
+
+    // We use the AUTOREPLACE mechanism to inject into our static JS and CSS certain
+    // values that are only known at doc build time. Since this mechanism is somewhat
+    // surprising when reading the code, please limit it to rustdoc.css.
+    write_minify(
+        "rustdoc.css",
+        static_files::RUSTDOC_CSS
+            .replace(
+                "/* AUTOREPLACE: */url(\"toggle-minus.svg\")",
+                &ver_url(cx, "toggle-minus.svg"),
+            )
+            .replace("/* AUTOREPLACE: */url(\"toggle-plus.svg\")", &ver_url(cx, "toggle-plus.svg"))
+            .replace("/* AUTOREPLACE: */url(\"down-arrow.svg\")", &ver_url(cx, "down-arrow.svg")),
+        cx,
+        options,
+    )?;
+
+    // Add all the static files. These may already exist, but we just
+    // overwrite them anyway to make sure that they're fresh and up-to-date.
+    write_minify("settings.css", static_files::SETTINGS_CSS, cx, options)?;
+    write_minify("noscript.css", static_files::NOSCRIPT_CSS, cx, options)?;
+
+    // To avoid "light.css" to be overwritten, we'll first run over the received themes and only
+    // then we'll run over the "official" styles.
+    let mut themes: FxHashSet = FxHashSet::default();
+
+    for entry in &cx.shared.style_files {
+        let theme = entry.basename()?;
+        let extension =
+            try_none!(try_none!(entry.path.extension(), &entry.path).to_str(), &entry.path);
+
+        // Handle the official themes
+        match theme.as_str() {
+            "light" => write_minify("light.css", static_files::themes::LIGHT, cx, options)?,
+            "dark" => write_minify("dark.css", static_files::themes::DARK, cx, options)?,
+            "ayu" => write_minify("ayu.css", static_files::themes::AYU, cx, options)?,
+            _ => {
+                // Handle added third-party themes
+                let filename = format!("{}.{}", theme, extension);
+                write_crate(&filename, &|| Ok(try_err!(fs::read(&entry.path), &entry.path)))?;
+            }
+        };
+
+        themes.insert(theme.to_owned());
+    }
+
+    if (*cx.shared).layout.logo.is_empty() {
+        write_toolchain("rust-logo.svg", static_files::RUST_LOGO_SVG)?;
+    }
+    if (*cx.shared).layout.favicon.is_empty() {
+        write_toolchain("favicon.svg", static_files::RUST_FAVICON_SVG)?;
+        write_toolchain("favicon-16x16.png", static_files::RUST_FAVICON_PNG_16)?;
+        write_toolchain("favicon-32x32.png", static_files::RUST_FAVICON_PNG_32)?;
+    }
+    write_toolchain("wheel.svg", static_files::WHEEL_SVG)?;
+    write_toolchain("clipboard.svg", static_files::CLIPBOARD_SVG)?;
+    write_toolchain("down-arrow.svg", static_files::DOWN_ARROW_SVG)?;
+    write_toolchain("toggle-minus.svg", static_files::TOGGLE_MINUS_PNG)?;
+    write_toolchain("toggle-plus.svg", static_files::TOGGLE_PLUS_PNG)?;
+
+    let mut themes: Vec<&String> = themes.iter().collect();
+    themes.sort();
+
+    write_minify("main.js", static_files::MAIN_JS, cx, options)?;
+    write_minify("search.js", static_files::SEARCH_JS, cx, options)?;
+    write_minify("settings.js", static_files::SETTINGS_JS, cx, options)?;
+
+    if cx.include_sources {
+        write_minify("source-script.js", static_files::sidebar::SOURCE_SCRIPT, cx, options)?;
+    }
+
+    write_minify("storage.js", static_files::STORAGE_JS, cx, options)?;
+
+    if cx.shared.layout.scrape_examples_extension {
+        cx.write_minify(
+            SharedResource::InvocationSpecific { basename: "scrape-examples.js" },
+            static_files::SCRAPE_EXAMPLES_JS,
+            options.enable_minification,
+            &options.emit,
+        )?;
+    }
+
+    if let Some(ref css) = cx.shared.layout.css_file_extension {
+        let buffer = try_err!(fs::read_to_string(css), css);
+        // This varies based on the invocation, so it can't go through the write_minify wrapper.
+        cx.write_minify(
+            SharedResource::InvocationSpecific { basename: "theme.css" },
+            buffer,
+            options.enable_minification,
+            &options.emit,
+        )?;
+    }
+    write_minify("normalize.css", static_files::NORMALIZE_CSS, cx, options)?;
+    for (name, contents) in &*FILES_UNVERSIONED {
+        cx.write_shared(SharedResource::Unversioned { name }, contents, &options.emit)?;
+    }
+
+    fn collect(path: &Path, krate: &str, key: &str) -> io::Result<(Vec, Vec)> {
+        let mut ret = Vec::new();
+        let mut krates = Vec::new();
+
+        if path.exists() {
+            let prefix = format!(r#"{}["{}"]"#, key, krate);
+            for line in BufReader::new(File::open(path)?).lines() {
+                let line = line?;
+                if !line.starts_with(key) {
+                    continue;
+                }
+                if line.starts_with(&prefix) {
+                    continue;
+                }
+                ret.push(line.to_string());
+                krates.push(
+                    line[key.len() + 2..]
+                        .split('"')
+                        .next()
+                        .map(|s| s.to_owned())
+                        .unwrap_or_else(String::new),
+                );
+            }
+        }
+        Ok((ret, krates))
+    }
+
+    fn collect_json(path: &Path, krate: &str) -> io::Result<(Vec, Vec)> {
+        let mut ret = Vec::new();
+        let mut krates = Vec::new();
+
+        if path.exists() {
+            let prefix = format!("\"{}\"", krate);
+            for line in BufReader::new(File::open(path)?).lines() {
+                let line = line?;
+                if !line.starts_with('"') {
+                    continue;
+                }
+                if line.starts_with(&prefix) {
+                    continue;
+                }
+                if line.ends_with(",\\") {
+                    ret.push(line[..line.len() - 2].to_string());
+                } else {
+                    // Ends with "\\" (it's the case for the last added crate line)
+                    ret.push(line[..line.len() - 1].to_string());
+                }
+                krates.push(
+                    line.split('"')
+                        .find(|s| !s.is_empty())
+                        .map(|s| s.to_owned())
+                        .unwrap_or_else(String::new),
+                );
+            }
+        }
+        Ok((ret, krates))
+    }
+
+    use std::ffi::OsString;
+
+    #[derive(Debug)]
+    struct Hierarchy {
+        elem: OsString,
+        children: FxHashMap,
+        elems: FxHashSet,
+    }
+
+    impl Hierarchy {
+        fn new(elem: OsString) -> Hierarchy {
+            Hierarchy { elem, children: FxHashMap::default(), elems: FxHashSet::default() }
+        }
+
+        fn to_json_string(&self) -> String {
+            let mut subs: Vec<&Hierarchy> = self.children.values().collect();
+            subs.sort_unstable_by(|a, b| a.elem.cmp(&b.elem));
+            let mut files = self
+                .elems
+                .iter()
+                .map(|s| format!("\"{}\"", s.to_str().expect("invalid osstring conversion")))
+                .collect::>();
+            files.sort_unstable();
+            let subs = subs.iter().map(|s| s.to_json_string()).collect::>().join(",");
+            let dirs = if subs.is_empty() && files.is_empty() {
+                String::new()
+            } else {
+                format!(",[{}]", subs)
+            };
+            let files = files.join(",");
+            let files = if files.is_empty() { String::new() } else { format!(",[{}]", files) };
+            format!(
+                "[\"{name}\"{dirs}{files}]",
+                name = self.elem.to_str().expect("invalid osstring conversion"),
+                dirs = dirs,
+                files = files
+            )
+        }
+    }
+
+    if cx.include_sources {
+        let mut hierarchy = Hierarchy::new(OsString::new());
+        for source in cx
+            .shared
+            .local_sources
+            .iter()
+            .filter_map(|p| p.0.strip_prefix(&cx.shared.src_root).ok())
+        {
+            let mut h = &mut hierarchy;
+            let mut elems = source
+                .components()
+                .filter_map(|s| match s {
+                    Component::Normal(s) => Some(s.to_owned()),
+                    _ => None,
+                })
+                .peekable();
+            loop {
+                let cur_elem = elems.next().expect("empty file path");
+                if elems.peek().is_none() {
+                    h.elems.insert(cur_elem);
+                    break;
+                } else {
+                    let e = cur_elem.clone();
+                    h = h.children.entry(cur_elem.clone()).or_insert_with(|| Hierarchy::new(e));
+                }
+            }
+        }
+
+        let dst = cx.dst.join(&format!("source-files{}.js", cx.shared.resource_suffix));
+        let make_sources = || {
+            let (mut all_sources, _krates) =
+                try_err!(collect_json(&dst, krate.name(cx.tcx()).as_str()), &dst);
+            all_sources.push(format!(
+                r#""{}":{}"#,
+                &krate.name(cx.tcx()),
+                hierarchy
+                    .to_json_string()
+                    // All these `replace` calls are because we have to go through JS string for JSON content.
+                    .replace('\\', r"\\")
+                    .replace('\'', r"\'")
+                    // We need to escape double quotes for the JSON.
+                    .replace("\\\"", "\\\\\"")
+            ));
+            all_sources.sort();
+            let mut v = String::from("var sourcesIndex = JSON.parse('{\\\n");
+            v.push_str(&all_sources.join(",\\\n"));
+            v.push_str("\\\n}');\ncreateSourceSidebar();\n");
+            Ok(v.into_bytes())
+        };
+        write_crate("source-files.js", &make_sources)?;
+    }
+
+    // Update the search index and crate list.
+    let dst = cx.dst.join(&format!("search-index{}.js", cx.shared.resource_suffix));
+    let (mut all_indexes, mut krates) =
+        try_err!(collect_json(&dst, krate.name(cx.tcx()).as_str()), &dst);
+    all_indexes.push(search_index);
+    krates.push(krate.name(cx.tcx()).to_string());
+    krates.sort();
+
+    // Sort the indexes by crate so the file will be generated identically even
+    // with rustdoc running in parallel.
+    all_indexes.sort();
+    write_crate("search-index.js", &|| {
+        let mut v = String::from("var searchIndex = JSON.parse('{\\\n");
+        v.push_str(&all_indexes.join(",\\\n"));
+        v.push_str(
+            r#"\
+}');
+if (typeof window !== 'undefined' && window.initSearch) {window.initSearch(searchIndex)};
+if (typeof exports !== 'undefined') {exports.searchIndex = searchIndex};
+"#,
+        );
+        Ok(v.into_bytes())
+    })?;
+
+    write_crate("crates.js", &|| {
+        let krates = krates.iter().map(|k| format!("\"{}\"", k)).join(",");
+        Ok(format!("window.ALL_CRATES = [{}];", krates).into_bytes())
+    })?;
+
+    if options.enable_index_page {
+        if let Some(index_page) = options.index_page.clone() {
+            let mut md_opts = options.clone();
+            md_opts.output = cx.dst.clone();
+            md_opts.external_html = (*cx.shared).layout.external_html.clone();
+
+            crate::markdown::render(&index_page, md_opts, cx.shared.edition())
+                .map_err(|e| Error::new(e, &index_page))?;
+        } else {
+            let shared = Rc::clone(&cx.shared);
+            let dst = cx.dst.join("index.html");
+            let page = layout::Page {
+                title: "Index of crates",
+                css_class: "mod",
+                root_path: "./",
+                static_root_path: shared.static_root_path.as_deref(),
+                description: "List of crates",
+                keywords: BASIC_KEYWORDS,
+                resource_suffix: &shared.resource_suffix,
+            };
+
+            let content = format!(
+                "
    \
+                     List of all crates\
+                
      {}
    ",
+                krates
+                    .iter()
+                    .map(|s| {
+                        format!(
+                            "
  • {}
    • ",
+                            ensure_trailing_slash(s),
+                            s
+                        )
+                    })
+                    .collect::()
+            );
+            let v = layout::render(&shared.layout, &page, "", content, &shared.style_files);
+            shared.fs.write(dst, v)?;
+        }
+    }
+
+    // Update the list of all implementors for traits
+    let dst = cx.dst.join("implementors");
+    let cache = cx.cache();
+    for (&did, imps) in &cache.implementors {
+        // Private modules can leak through to this phase of rustdoc, which
+        // could contain implementations for otherwise private types. In some
+        // rare cases we could find an implementation for an item which wasn't
+        // indexed, so we just skip this step in that case.
+        //
+        // FIXME: this is a vague explanation for why this can't be a `get`, in
+        //        theory it should be...
+        let (remote_path, remote_item_type) = match cache.exact_paths.get(&did) {
+            Some(p) => match cache.paths.get(&did).or_else(|| cache.external_paths.get(&did)) {
+                Some((_, t)) => (p, t),
+                None => continue,
+            },
+            None => match cache.external_paths.get(&did) {
+                Some((p, t)) => (p, t),
+                None => continue,
+            },
+        };
+
+        #[derive(Serialize)]
+        struct Implementor {
+            text: String,
+            synthetic: bool,
+            types: Vec,
+        }
+
+        let implementors = imps
+            .iter()
+            .filter_map(|imp| {
+                // If the trait and implementation are in the same crate, then
+                // there's no need to emit information about it (there's inlining
+                // going on). If they're in different crates then the crate defining
+                // the trait will be interested in our implementation.
+                //
+                // If the implementation is from another crate then that crate
+                // should add it.
+                if imp.impl_item.item_id.krate() == did.krate || !imp.impl_item.item_id.is_local() {
+                    None
+                } else {
+                    Some(Implementor {
+                        text: imp.inner_impl().print(false, cx).to_string(),
+                        synthetic: imp.inner_impl().kind.is_auto(),
+                        types: collect_paths_for_type(imp.inner_impl().for_.clone(), cache),
+                    })
+                }
+            })
+            .collect::>();
+
+        // Only create a js file if we have impls to add to it. If the trait is
+        // documented locally though we always create the file to avoid dead
+        // links.
+        if implementors.is_empty() && !cache.paths.contains_key(&did) {
+            continue;
+        }
+
+        let implementors = format!(
+            r#"implementors["{}"] = {};"#,
+            krate.name(cx.tcx()),
+            serde_json::to_string(&implementors).unwrap()
+        );
+
+        let mut mydst = dst.clone();
+        for part in &remote_path[..remote_path.len() - 1] {
+            mydst.push(part.to_string());
+        }
+        cx.shared.ensure_dir(&mydst)?;
+        mydst.push(&format!("{}.{}.js", remote_item_type, remote_path[remote_path.len() - 1]));
+
+        let (mut all_implementors, _) =
+            try_err!(collect(&mydst, krate.name(cx.tcx()).as_str(), "implementors"), &mydst);
+        all_implementors.push(implementors);
+        // Sort the implementors by crate so the file will be generated
+        // identically even with rustdoc running in parallel.
+        all_implementors.sort();
+
+        let mut v = String::from("(function() {var implementors = {};\n");
+        for implementor in &all_implementors {
+            writeln!(v, "{}", *implementor).unwrap();
+        }
+        v.push_str(
+            "if (window.register_implementors) {\
+                 window.register_implementors(implementors);\
+             } else {\
+                 window.pending_implementors = implementors;\
+             }",
+        );
+        v.push_str("})()");
+        cx.shared.fs.write(mydst, v)?;
+    }
+    Ok(())
+}
diff --git a/src/librustdoc/html/sources.rs b/src/librustdoc/html/sources.rs
new file mode 100644
index 000000000..d0fd637ba
--- /dev/null
+++ b/src/librustdoc/html/sources.rs
@@ -0,0 +1,303 @@
+use crate::clean;
+use crate::docfs::PathError;
+use crate::error::Error;
+use crate::html::format::Buffer;
+use crate::html::highlight;
+use crate::html::layout;
+use crate::html::render::{Context, BASIC_KEYWORDS};
+use crate::visit::DocVisitor;
+
+use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_hir::def_id::LOCAL_CRATE;
+use rustc_middle::ty::TyCtxt;
+use rustc_session::Session;
+use rustc_span::edition::Edition;
+use rustc_span::source_map::FileName;
+
+use std::ffi::OsStr;
+use std::fs;
+use std::path::{Component, Path, PathBuf};
+use std::rc::Rc;
+
+pub(crate) fn render(cx: &mut Context<'_>, krate: &clean::Crate) -> Result<(), Error> {
+    info!("emitting source files");
+
+    let dst = cx.dst.join("src").join(krate.name(cx.tcx()).as_str());
+    cx.shared.ensure_dir(&dst)?;
+
+    let mut collector = SourceCollector { dst, cx, emitted_local_sources: FxHashSet::default() };
+    collector.visit_crate(krate);
+    Ok(())
+}
+
+pub(crate) fn collect_local_sources<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    src_root: &Path,
+    krate: &clean::Crate,
+) -> FxHashMap {
+    let mut lsc = LocalSourcesCollector { tcx, local_sources: FxHashMap::default(), src_root };
+    lsc.visit_crate(krate);
+    lsc.local_sources
+}
+
+struct LocalSourcesCollector<'a, 'tcx> {
+    tcx: TyCtxt<'tcx>,
+    local_sources: FxHashMap,
+    src_root: &'a Path,
+}
+
+fn is_real_and_local(span: clean::Span, sess: &Session) -> bool {
+    span.cnum(sess) == LOCAL_CRATE && span.filename(sess).is_real()
+}
+
+impl LocalSourcesCollector<'_, '_> {
+    fn add_local_source(&mut self, item: &clean::Item) {
+        let sess = self.tcx.sess;
+        let span = item.span(self.tcx);
+        // skip all synthetic "files"
+        if !is_real_and_local(span, sess) {
+            return;
+        }
+        let filename = span.filename(sess);
+        let p = if let FileName::Real(file) = filename {
+            match file.into_local_path() {
+                Some(p) => p,
+                None => return,
+            }
+        } else {
+            return;
+        };
+        if self.local_sources.contains_key(&*p) {
+            // We've already emitted this source
+            return;
+        }
+
+        let mut href = String::new();
+        clean_path(self.src_root, &p, false, |component| {
+            href.push_str(&component.to_string_lossy());
+            href.push('/');
+        });
+
+        let mut src_fname = p.file_name().expect("source has no filename").to_os_string();
+        src_fname.push(".html");
+        href.push_str(&src_fname.to_string_lossy());
+        self.local_sources.insert(p, href);
+    }
+}
+
+impl DocVisitor for LocalSourcesCollector<'_, '_> {
+    fn visit_item(&mut self, item: &clean::Item) {
+        self.add_local_source(item);
+
+        self.visit_item_recur(item)
+    }
+}
+
+/// Helper struct to render all source code to HTML pages
+struct SourceCollector<'a, 'tcx> {
+    cx: &'a mut Context<'tcx>,
+
+    /// Root destination to place all HTML output into
+    dst: PathBuf,
+    emitted_local_sources: FxHashSet,
+}
+
+impl DocVisitor for SourceCollector<'_, '_> {
+    fn visit_item(&mut self, item: &clean::Item) {
+        if !self.cx.include_sources {
+            return;
+        }
+
+        let tcx = self.cx.tcx();
+        let span = item.span(tcx);
+        let sess = tcx.sess;
+
+        // If we're not rendering sources, there's nothing to do.
+        // If we're including source files, and we haven't seen this file yet,
+        // then we need to render it out to the filesystem.
+        if is_real_and_local(span, sess) {
+            let filename = span.filename(sess);
+            let span = span.inner();
+            let pos = sess.source_map().lookup_source_file(span.lo());
+            let file_span = span.with_lo(pos.start_pos).with_hi(pos.end_pos);
+            // If it turns out that we couldn't read this file, then we probably
+            // can't read any of the files (generating html output from json or
+            // something like that), so just don't include sources for the
+            // entire crate. The other option is maintaining this mapping on a
+            // per-file basis, but that's probably not worth it...
+            self.cx.include_sources = match self.emit_source(&filename, file_span) {
+                Ok(()) => true,
+                Err(e) => {
+                    self.cx.shared.tcx.sess.span_err(
+                        span,
+                        &format!(
+                            "failed to render source code for `{}`: {}",
+                            filename.prefer_local(),
+                            e,
+                        ),
+                    );
+                    false
+                }
+            };
+        }
+
+        self.visit_item_recur(item)
+    }
+}
+
+impl SourceCollector<'_, '_> {
+    /// Renders the given filename into its corresponding HTML source file.
+    fn emit_source(
+        &mut self,
+        filename: &FileName,
+        file_span: rustc_span::Span,
+    ) -> Result<(), Error> {
+        let p = match *filename {
+            FileName::Real(ref file) => {
+                if let Some(local_path) = file.local_path() {
+                    local_path.to_path_buf()
+                } else {
+                    unreachable!("only the current crate should have sources emitted");
+                }
+            }
+            _ => return Ok(()),
+        };
+        if self.emitted_local_sources.contains(&*p) {
+            // We've already emitted this source
+            return Ok(());
+        }
+
+        let contents = match fs::read_to_string(&p) {
+            Ok(contents) => contents,
+            Err(e) => {
+                return Err(Error::new(e, &p));
+            }
+        };
+
+        // Remove the utf-8 BOM if any
+        let contents = contents.strip_prefix('\u{feff}').unwrap_or(&contents);
+
+        let shared = Rc::clone(&self.cx.shared);
+        // Create the intermediate directories
+        let mut cur = self.dst.clone();
+        let mut root_path = String::from("../../");
+        clean_path(&shared.src_root, &p, false, |component| {
+            cur.push(component);
+            root_path.push_str("../");
+        });
+
+        shared.ensure_dir(&cur)?;
+
+        let src_fname = p.file_name().expect("source has no filename").to_os_string();
+        let mut fname = src_fname.clone();
+        fname.push(".html");
+        cur.push(&fname);
+
+        let title = format!("{} - source", src_fname.to_string_lossy());
+        let desc = format!("Source of the Rust file `{}`.", filename.prefer_remapped());
+        let page = layout::Page {
+            title: &title,
+            css_class: "source",
+            root_path: &root_path,
+            static_root_path: shared.static_root_path.as_deref(),
+            description: &desc,
+            keywords: BASIC_KEYWORDS,
+            resource_suffix: &shared.resource_suffix,
+        };
+        let v = layout::render(
+            &shared.layout,
+            &page,
+            "",
+            |buf: &mut _| {
+                let cx = &mut self.cx;
+                print_src(
+                    buf,
+                    contents,
+                    cx.shared.edition(),
+                    file_span,
+                    cx,
+                    &root_path,
+                    None,
+                    SourceContext::Standalone,
+                )
+            },
+            &shared.style_files,
+        );
+        shared.fs.write(cur, v)?;
+        self.emitted_local_sources.insert(p);
+        Ok(())
+    }
+}
+
+/// Takes a path to a source file and cleans the path to it. This canonicalizes
+/// things like ".." to components which preserve the "top down" hierarchy of a
+/// static HTML tree. Each component in the cleaned path will be passed as an
+/// argument to `f`. The very last component of the path (ie the file name) will
+/// be passed to `f` if `keep_filename` is true, and ignored otherwise.
+pub(crate) fn clean_path(src_root: &Path, p: &Path, keep_filename: bool, mut f: F)
+where
+    F: FnMut(&OsStr),
+{
+    // make it relative, if possible
+    let p = p.strip_prefix(src_root).unwrap_or(p);
+
+    let mut iter = p.components().peekable();
+
+    while let Some(c) = iter.next() {
+        if !keep_filename && iter.peek().is_none() {
+            break;
+        }
+
+        match c {
+            Component::ParentDir => f("up".as_ref()),
+            Component::Normal(c) => f(c),
+            _ => continue,
+        }
+    }
+}
+
+pub(crate) enum SourceContext {
+    Standalone,
+    Embedded { offset: usize },
+}
+
+/// Wrapper struct to render the source code of a file. This will do things like
+/// adding line numbers to the left-hand side.
+pub(crate) fn print_src(
+    buf: &mut Buffer,
+    s: &str,
+    edition: Edition,
+    file_span: rustc_span::Span,
+    context: &Context<'_>,
+    root_path: &str,
+    decoration_info: Option,
+    source_context: SourceContext,
+) {
+    let lines = s.lines().count();
+    let mut line_numbers = Buffer::empty_from(buf);
+    line_numbers.write_str("
    ");
+    match source_context {
+        SourceContext::Standalone => {
+            for line in 1..=lines {
+                writeln!(line_numbers, "{0}", line)
+            }
+        }
+        SourceContext::Embedded { offset } => {
+            for line in 1..=lines {
+                writeln!(line_numbers, "{0}", line + offset)
+            }
+        }
+    }
+    line_numbers.write_str("
    ");
+    highlight::render_with_highlighting(
+        s,
+        buf,
+        None,
+        None,
+        None,
+        edition,
+        Some(line_numbers),
+        Some(highlight::HrefContext { context, file_span, root_path }),
+        decoration_info,
+    );
+}
diff --git a/src/librustdoc/html/static/.eslintrc.js b/src/librustdoc/html/static/.eslintrc.js
new file mode 100644
index 000000000..fcd925bb3
--- /dev/null
+++ b/src/librustdoc/html/static/.eslintrc.js
@@ -0,0 +1,96 @@
+module.exports = {
+    "env": {
+        "browser": true,
+        "es6": true
+    },
+    "extends": "eslint:recommended",
+    "parserOptions": {
+        "ecmaVersion": 2015,
+        "sourceType": "module"
+    },
+    "rules": {
+        "linebreak-style": [
+            "error",
+            "unix"
+        ],
+        "semi": [
+            "error",
+            "always"
+        ],
+        "quotes": [
+            "error",
+            "double"
+        ],
+        "linebreak-style": [
+            "error",
+            "unix"
+        ],
+        "no-trailing-spaces": "error",
+        "no-var": ["error"],
+        "prefer-const": ["error"],
+        "prefer-arrow-callback": ["error"],
+        "brace-style": [
+            "error",
+            "1tbs",
+            { "allowSingleLine": false }
+        ],
+        "keyword-spacing": [
+            "error",
+            { "before": true, "after": true }
+        ],
+        "arrow-spacing": [
+            "error",
+            { "before": true, "after": true }
+        ],
+        "key-spacing": [
+            "error",
+            { "beforeColon": false, "afterColon": true, "mode": "strict" }
+        ],
+        "func-call-spacing": ["error", "never"],
+        "space-infix-ops": "error",
+        "space-before-function-paren": ["error", "never"],
+        "space-before-blocks": "error",
+        "comma-dangle": ["error", "always-multiline"],
+        "comma-style": ["error", "last"],
+        "max-len": ["error", { "code": 100, "tabWidth": 4 }],
+        "eol-last": ["error", "always"],
+        "arrow-parens": ["error", "as-needed"],
+        "no-unused-vars": [
+            "error",
+            {
+                "argsIgnorePattern": "^_",
+                "varsIgnorePattern": "^_"
+            }
+        ],
+        "eqeqeq": "error",
+        "no-const-assign": "error",
+        "no-debugger": "error",
+        "no-dupe-args": "error",
+        "no-dupe-else-if": "error",
+        "no-dupe-keys": "error",
+        "no-duplicate-case": "error",
+        "no-ex-assign": "error",
+        "no-fallthrough": "error",
+        "no-invalid-regexp": "error",
+        "no-import-assign": "error",
+        "no-self-compare": "error",
+        "no-template-curly-in-string": "error",
+        "block-scoped-var": "error",
+        "guard-for-in": "error",
+        "no-alert": "error",
+        "no-confusing-arrow": "error",
+        "no-div-regex": "error",
+        "no-floating-decimal": "error",
+        "no-implicit-globals": "error",
+        "no-implied-eval": "error",
+        "no-label-var": "error",
+        "no-lonely-if": "error",
+        "no-mixed-operators": "error",
+        "no-multi-assign": "error",
+        "no-return-assign": "error",
+        "no-script-url": "error",
+        "no-sequences": "error",
+        "no-throw-literal": "error",
+        "no-div-regex": "error",
+    }
+};
diff --git a/src/librustdoc/html/static/COPYRIGHT.txt b/src/librustdoc/html/static/COPYRIGHT.txt
new file mode 100644
index 000000000..34e48134c
--- /dev/null
+++ b/src/librustdoc/html/static/COPYRIGHT.txt
@@ -0,0 +1,46 @@
+These documentation pages include resources by third parties. This copyright
+file applies only to those resources. The following third party resources are
+included, and carry their own copyright notices and license terms:
+
+* Fira Sans (FiraSans-Regular.woff2, FiraSans-Medium.woff2):
+
+    Copyright (c) 2014, Mozilla Foundation https://mozilla.org/
+    with Reserved Font Name Fira Sans.
+
+    Copyright (c) 2014, Telefonica S.A.
+
+    Licensed under the SIL Open Font License, Version 1.1.
+    See FiraSans-LICENSE.txt.
+
+* rustdoc.css, main.js, and playpen.js:
+
+    Copyright 2015 The Rust Developers.
+    Licensed under the Apache License, Version 2.0 (see LICENSE-APACHE.txt) or
+    the MIT license (LICENSE-MIT.txt) at your option.
+
+* normalize.css:
+
+    Copyright (c) Nicolas Gallagher and Jonathan Neal.
+    Licensed under the MIT license (see LICENSE-MIT.txt).
+
+* Source Code Pro (SourceCodePro-Regular.ttf.woff2,
+    SourceCodePro-Semibold.ttf.woff2, SourceCodePro-It.ttf.woff2):
+
+    Copyright 2010, 2012 Adobe Systems Incorporated (http://www.adobe.com/),
+    with Reserved Font Name 'Source'. All Rights Reserved. Source is a trademark
+    of Adobe Systems Incorporated in the United States and/or other countries.
+
+    Licensed under the SIL Open Font License, Version 1.1.
+    See SourceCodePro-LICENSE.txt.
+
+* Source Serif 4 (SourceSerif4-Regular.ttf.woff2, SourceSerif4-Bold.ttf.woff2,
+    SourceSerif4-It.ttf.woff2):
+
+    Copyright 2014-2021 Adobe (http://www.adobe.com/), with Reserved Font Name
+    'Source'. All Rights Reserved. Source is a trademark of Adobe in the United
+    States and/or other countries.
+
+    Licensed under the SIL Open Font License, Version 1.1.
+    See SourceSerif4-LICENSE.md.
+
+This copyright file is intended to be distributed with rustdoc output.
diff --git a/src/librustdoc/html/static/LICENSE-APACHE.txt b/src/librustdoc/html/static/LICENSE-APACHE.txt
new file mode 100644
index 000000000..16fe87b06
--- /dev/null
+++ b/src/librustdoc/html/static/LICENSE-APACHE.txt
@@ -0,0 +1,201 @@
+                              Apache License
+                        Version 2.0, January 2004
+                     http://www.apache.org/licenses/
+
+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+1. Definitions.
+
+   "License" shall mean the terms and conditions for use, reproduction,
+   and distribution as defined by Sections 1 through 9 of this document.
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+   "Licensor" shall mean the copyright owner or entity authorized by
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+   "Legal Entity" shall mean the union of the acting entity and all
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+   direction or management of such entity, whether by contract or
+   otherwise, or (ii) ownership of fifty percent (50%) or more of the
+   outstanding shares, or (iii) beneficial ownership of such entity.
+
+   "You" (or "Your") shall mean an individual or Legal Entity
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+
+   "Work" shall mean the work of authorship, whether in Source or
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+   "Derivative Works" shall mean any work, whether in Source or Object
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+   editorial revisions, annotations, elaborations, or other modifications
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+   "Contribution" shall mean any work of authorship, including
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+   You may add Your own copyright statement to Your modifications and
+   may provide additional or different license terms and conditions
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+   the conditions stated in this License.
+
+5. Submission of Contributions. Unless You explicitly state otherwise,
+   any Contribution intentionally submitted for inclusion in the Work
+   by You to the Licensor shall be under the terms and conditions of
+   this License, without any additional terms or conditions.
+   Notwithstanding the above, nothing herein shall supersede or modify
+   the terms of any separate license agreement you may have executed
+   with Licensor regarding such Contributions.
+
+6. Trademarks. This License does not grant permission to use the trade
+   names, trademarks, service marks, or product names of the Licensor,
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+   origin of the Work and reproducing the content of the NOTICE file.
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+7. Disclaimer of Warranty. Unless required by applicable law or
+   agreed to in writing, Licensor provides the Work (and each
+   Contributor provides its Contributions) on an "AS IS" BASIS,
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+8. Limitation of Liability. In no event and under no legal theory,
+   whether in tort (including negligence), contract, or otherwise,
+   unless required by applicable law (such as deliberate and grossly
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+END OF TERMS AND CONDITIONS
+
+APPENDIX: How to apply the Apache License to your work.
+
+   To apply the Apache License to your work, attach the following
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+you may not use this file except in compliance with the License.
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+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
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diff --git a/src/librustdoc/html/static/LICENSE-MIT.txt b/src/librustdoc/html/static/LICENSE-MIT.txt
new file mode 100644
index 000000000..31aa79387
--- /dev/null
+++ b/src/librustdoc/html/static/LICENSE-MIT.txt
@@ -0,0 +1,23 @@
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
diff --git a/src/librustdoc/html/static/css/normalize.css b/src/librustdoc/html/static/css/normalize.css
new file mode 100644
index 000000000..fdb8a8c65
--- /dev/null
+++ b/src/librustdoc/html/static/css/normalize.css
@@ -0,0 +1,2 @@
+/* ignore-tidy-linelength */
+/*! normalize.css v8.0.1 | MIT License | github.com/necolas/normalize.css */ html{line-height:1.15;-webkit-text-size-adjust:100%}body{margin:0}main{display:block}h1{font-size:2em;margin:0.67em 0}hr{box-sizing:content-box;height:0;overflow:visible}pre{font-family:monospace, monospace;font-size:1em}a{background-color:transparent}abbr[title]{border-bottom:none;text-decoration:underline;text-decoration:underline dotted}b,strong{font-weight:bolder}code,kbd,samp{font-family:monospace, monospace;font-size:1em}small{font-size:80%}sub,sup{font-size:75%;line-height:0;position:relative;vertical-align:baseline}sub{bottom:-0.25em}sup{top:-0.5em}img{border-style:none}button,input,optgroup,select,textarea{font-family:inherit;font-size:100%;line-height:1.15;margin:0}button,input{overflow:visible}button,select{text-transform:none}[type="button"],[type="reset"],[type="submit"],button{-webkit-appearance:button}[type="button"]::-moz-focus-inner,[type="reset"]::-moz-focus-inner,[type="submit"]::-moz-focus-inner,button::-moz-focus-inner{border-style:none;padding:0}[type="button"]:-moz-focusring,[type="reset"]:-moz-focusring,[type="submit"]:-moz-focusring,button:-moz-focusring{outline:1px dotted ButtonText}fieldset{padding:0.35em 0.75em 0.625em}legend{box-sizing:border-box;color:inherit;display:table;max-width:100%;padding:0;white-space:normal}progress{vertical-align:baseline}textarea{overflow:auto}[type="checkbox"],[type="radio"]{box-sizing:border-box;padding:0}[type="number"]::-webkit-inner-spin-button,[type="number"]::-webkit-outer-spin-button{height:auto}[type="search"]{-webkit-appearance:textfield;outline-offset:-2px}[type="search"]::-webkit-search-decoration{-webkit-appearance:none}::-webkit-file-upload-button{-webkit-appearance:button;font:inherit}details{display:block}summary{display:list-item}template{display:none}[hidden]{display:none}
diff --git a/src/librustdoc/html/static/css/noscript.css b/src/librustdoc/html/static/css/noscript.css
new file mode 100644
index 000000000..0a19a99ab
--- /dev/null
+++ b/src/librustdoc/html/static/css/noscript.css
@@ -0,0 +1,20 @@
+/*
+This whole CSS file is used only in case rustdoc is rendered with javascript disabled. Since a lot
+of content is hidden by default (depending on the settings too), we have to overwrite some of the
+rules.
+*/
+
+#main-content .attributes {
+	/* Since there is no toggle (the "[-]") when JS is disabled, no need for this margin either. */
+	margin-left: 0 !important;
+}
+
+#copy-path {
+	/* It requires JS to work so no need to display it in this case. */
+	display: none;
+}
+
+.sub {
+	/* The search bar and related controls don't work without JS */
+	display: none;
+}
diff --git a/src/librustdoc/html/static/css/rustdoc.css b/src/librustdoc/html/static/css/rustdoc.css
new file mode 100644
index 000000000..83fe14550
--- /dev/null
+++ b/src/librustdoc/html/static/css/rustdoc.css
@@ -0,0 +1,2335 @@
+/* See FiraSans-LICENSE.txt for the Fira Sans license. */
+@font-face {
+	font-family: 'Fira Sans';
+	font-style: normal;
+	font-weight: 400;
+	src: local('Fira Sans'),
+		url("FiraSans-Regular.woff2") format("woff2");
+	font-display: swap;
+}
+@font-face {
+	font-family: 'Fira Sans';
+	font-style: normal;
+	font-weight: 500;
+	src: local('Fira Sans Medium'),
+		url("FiraSans-Medium.woff2") format("woff2");
+	font-display: swap;
+}
+
+/* See SourceSerif4-LICENSE.md for the Source Serif 4 license. */
+@font-face {
+	font-family: 'Source Serif 4';
+	font-style: normal;
+	font-weight: 400;
+	src: local('Source Serif 4'),
+		url("SourceSerif4-Regular.ttf.woff2") format("woff2");
+	font-display: swap;
+}
+@font-face {
+	font-family: 'Source Serif 4';
+	font-style: italic;
+	font-weight: 400;
+	src: local('Source Serif 4 Italic'),
+		url("SourceSerif4-It.ttf.woff2") format("woff2");
+	font-display: swap;
+}
+@font-face {
+	font-family: 'Source Serif 4';
+	font-style: normal;
+	font-weight: 700;
+	src: local('Source Serif 4 Bold'),
+		url("SourceSerif4-Bold.ttf.woff2") format("woff2");
+	font-display: swap;
+}
+
+/* See SourceCodePro-LICENSE.txt for the Source Code Pro license. */
+@font-face {
+	font-family: 'Source Code Pro';
+	font-style: normal;
+	font-weight: 400;
+	/* Avoid using locally installed font because bad versions are in circulation:
+	 * see https://github.com/rust-lang/rust/issues/24355 */
+	src: url("SourceCodePro-Regular.ttf.woff2") format("woff2");
+	font-display: swap;
+}
+@font-face {
+	font-family: 'Source Code Pro';
+	font-style: italic;
+	font-weight: 400;
+	src: url("SourceCodePro-It.ttf.woff2") format("woff2");
+	font-display: swap;
+}
+@font-face {
+	font-family: 'Source Code Pro';
+	font-style: normal;
+	font-weight: 600;
+	src: url("SourceCodePro-Semibold.ttf.woff2") format("woff2");
+	font-display: swap;
+}
+
+/* Avoid using legacy CJK serif fonts in Windows like Batang. */
+@font-face {
+	font-family: 'NanumBarunGothic';
+	src: url("NanumBarunGothic.ttf.woff2") format("woff2");
+	font-display: swap;
+	unicode-range: U+AC00-D7AF, U+1100-11FF, U+3130-318F, U+A960-A97F, U+D7B0-D7FF;
+}
+
+* {
+	-webkit-box-sizing: border-box;
+	-moz-box-sizing: border-box;
+	box-sizing: border-box;
+}
+
+/* This part handles the "default" theme being used depending on the system one. */
+html {
+	content: "";
+}
+@media (prefers-color-scheme: light) {
+	html {
+		content: "light";
+	}
+}
+@media (prefers-color-scheme: dark) {
+	html {
+		content: "dark";
+	}
+}
+
+/* General structure and fonts */
+
+body {
+	/* Line spacing at least 1.5 per Web Content Accessibility Guidelines
+	   https://www.w3.org/WAI/WCAG21/Understanding/visual-presentation.html */
+	font: 1rem/1.5 "Source Serif 4", NanumBarunGothic, serif;
+	margin: 0;
+	position: relative;
+	/* We use overflow-wrap: break-word for Safari, which doesn't recognize
+	   `anywhere`: https://developer.mozilla.org/en-US/docs/Web/CSS/overflow-wrap */
+	overflow-wrap: break-word;
+	/* Then override it with `anywhere`, which is required to make non-Safari browsers break
+	   more aggressively when we want them to. */
+	overflow-wrap: anywhere;
+
+	-webkit-font-feature-settings: "kern", "liga";
+	-moz-font-feature-settings: "kern", "liga";
+	font-feature-settings: "kern", "liga";
+
+	background-color: var(--main-background-color);
+	color: var(--main-color);
+}
+
+h1 {
+	font-size: 1.5rem; /* 24px */
+}
+h2 {
+	font-size: 1.375rem; /* 22px */
+}
+h3 {
+	font-size: 1.25rem; /* 20px */
+}
+h1, h2, h3, h4, h5, h6 {
+	font-weight: 500;
+}
+h1, h2, h3, h4 {
+	margin: 20px 0 15px 0;
+	padding-bottom: 6px;
+}
+.docblock h3, .docblock h4, h5, h6 {
+	margin: 15px 0 5px 0;
+}
+h1.fqn {
+	margin: 0;
+	padding: 0;
+	border-bottom-color: var(--headings-border-bottom-color);
+}
+h2, h3, h4 {
+	border-bottom-color: var(--headings-border-bottom-color);
+}
+.main-heading {
+	display: flex;
+	flex-wrap: wrap;
+	justify-content: space-between;
+	padding-bottom: 6px;
+	margin-bottom: 15px;
+}
+.main-heading a:hover {
+	text-decoration: underline;
+}
+#toggle-all-docs {
+	text-decoration: none;
+}
+/* The only headings that get underlines are:
+	 Markdown-generated headings within the top-doc
+	 Rustdoc-generated h2 section headings (e.g. "Implementations", "Required Methods", etc)
+	Underlines elsewhere in the documentation break up visual flow and tend to invert
+	section hierarchies. */
+h2,
+.top-doc .docblock > h3,
+.top-doc .docblock > h4 {
+	border-bottom: 1px solid var(--headings-border-bottom-color);
+}
+h3.code-header {
+	font-size: 1.125rem; /* 18px */
+}
+h4.code-header {
+	font-size: 1rem;
+}
+.code-header {
+	font-weight: 600;
+	border-bottom-style: none;
+	margin: 0;
+	padding: 0;
+	margin-top: 0.6em;
+	margin-bottom: 0.4em;
+}
+.impl,
+.impl-items .method,
+.methods .method,
+.impl-items .type,
+.methods .type,
+.impl-items .associatedconstant,
+.methods .associatedconstant,
+.impl-items .associatedtype,
+.methods .associatedtype {
+	flex-basis: 100%;
+	font-weight: 600;
+	position: relative;
+}
+
+div.impl-items > div {
+	padding-left: 0;
+}
+
+h1, h2, h3, h4, h5, h6,
+.sidebar,
+.mobile-topbar,
+a.source,
+.search-input,
+.search-results .result-name,
+.content table td:first-child > a,
+.item-left > a,
+.out-of-band,
+span.since,
+#source-sidebar, #sidebar-toggle,
+details.rustdoc-toggle > summary::before,
+div.impl-items > div:not(.docblock):not(.item-info),
+.content ul.crate a.crate,
+a.srclink,
+#main-content > .since,
+#help-button > button,
+details.rustdoc-toggle.top-doc > summary,
+details.rustdoc-toggle.top-doc > summary::before,
+details.rustdoc-toggle.non-exhaustive > summary,
+details.rustdoc-toggle.non-exhaustive > summary::before,
+.scraped-example-title,
+.more-examples-toggle summary, .more-examples-toggle .hide-more,
+.example-links a,
+/* This selector is for the items listed in the "all items" page. */
+#main-content > ul.docblock > li > a {
+	font-family: "Fira Sans", Arial, NanumBarunGothic, sans-serif;
+}
+
+h1, h2, h3, h4,
+a#toggle-all-docs,
+a.anchor,
+.small-section-header a,
+#source-sidebar a,
+pre.rust a,
+.sidebar h2 a,
+.sidebar h3 a,
+.mobile-topbar h2 a,
+.in-band a,
+.search-results a,
+.module-item .stab,
+.import-item .stab,
+.result-name .primitive > i, .result-name .keyword > i,
+.content .method .where,
+.content .fn .where,
+.content .where.fmt-newline {
+	color: var(--main-color);
+}
+
+ol, ul {
+	padding-left: 24px;
+}
+ul ul, ol ul, ul ol, ol ol {
+	margin-bottom: .625em;
+}
+
+p {
+	/* Paragraph spacing at least 1.5 times line spacing per Web Content Accessibility Guidelines.
+	   Line-height is 1.5rem, so line spacing is .5rem; .75em is 1.5 times that.
+	   https://www.w3.org/WAI/WCAG21/Understanding/visual-presentation.html */
+	margin: 0 0 .75em 0;
+}
+
+summary {
+	outline: none;
+}
+
+/* Fix some style changes due to normalize.css 8 */
+
+td,
+th {
+	padding: 0;
+}
+
+table {
+	border-collapse: collapse;
+}
+
+button,
+input,
+optgroup,
+select,
+textarea {
+	color: inherit;
+	font: inherit;
+	margin: 0;
+}
+
+button {
+	/* Buttons on Safari have different default padding than other platforms. Make them the same. */
+	padding: 1px 6px;
+}
+
+/* end tweaks for normalize.css 8 */
+
+.rustdoc {
+	display: flex;
+	flex-direction: row;
+	flex-wrap: nowrap;
+}
+
+main {
+	position: relative;
+	flex-grow: 1;
+	padding: 10px 15px 40px 45px;
+	min-width: 0;
+}
+
+.source main {
+	padding: 15px;
+}
+
+.width-limiter {
+	max-width: 960px;
+	margin-right: auto;
+}
+
+.source .width-limiter {
+	max-width: unset;
+}
+
+details:not(.rustdoc-toggle) summary {
+	margin-bottom: .6em;
+}
+
+code, pre, a.test-arrow, .code-header {
+	font-family: "Source Code Pro", monospace;
+}
+.docblock code, .docblock-short code {
+	border-radius: 3px;
+	padding: 0 0.125em;
+}
+.docblock pre code, .docblock-short pre code {
+	padding: 0;
+}
+pre {
+	padding: 14px;
+}
+.docblock.item-decl {
+	margin-left: 0;
+}
+.item-decl pre {
+	overflow-x: auto;
+}
+
+.source .content pre {
+	padding: 20px;
+}
+
+img {
+	max-width: 100%;
+}
+
+li {
+	position: relative;
+}
+
+.source .content {
+	max-width: none;
+	overflow: visible;
+	margin-left: 0px;
+}
+
+nav.sub {
+	position: relative;
+	font-size: 1rem;
+}
+
+.sub-container {
+	display: flex;
+	flex-direction: row;
+	flex-wrap: nowrap;
+}
+
+.sub-logo-container {
+	display: none;
+	margin-right: 20px;
+}
+
+.source .sub-logo-container {
+	display: block;
+}
+
+.source .sub-logo-container > img {
+	height: 60px;
+	width: 60px;
+	object-fit: contain;
+}
+
+.sidebar, .mobile-topbar, .sidebar-menu-toggle {
+	background-color: var(--sidebar-background-color);
+}
+
+.sidebar {
+	font-size: 0.875rem;
+	width: 250px;
+	min-width: 200px;
+	overflow-y: scroll;
+	position: sticky;
+	height: 100vh;
+	top: 0;
+	left: 0;
+}
+
+.sidebar-elems,
+.sidebar > .location {
+	padding-left: 24px;
+}
+
+.sidebar .location {
+	overflow-wrap: anywhere;
+}
+
+.rustdoc.source .sidebar {
+	width: 50px;
+	min-width: 0px;
+	max-width: 300px;
+	flex-grow: 0;
+	flex-shrink: 0;
+	flex-basis: auto;
+	border-right: 1px solid;
+	overflow-x: hidden;
+	/* The sidebar is by default hidden  */
+	overflow-y: hidden;
+}
+
+.rustdoc.source .sidebar .sidebar-logo {
+	display: none;
+}
+
+.source .sidebar, #sidebar-toggle, #source-sidebar {
+	background-color: var(--sidebar-background-color);
+}
+
+#sidebar-toggle > button:hover, #sidebar-toggle > button:focus {
+	background-color: var(--sidebar-background-color-hover);
+}
+
+.source .sidebar > *:not(#sidebar-toggle) {
+	opacity: 0;
+	visibility: hidden;
+}
+
+.source-sidebar-expanded .source .sidebar {
+	overflow-y: auto;
+}
+
+.source-sidebar-expanded .source .sidebar > *:not(#sidebar-toggle) {
+	opacity: 1;
+	visibility: visible;
+}
+
+#all-types {
+	margin-top: 1em;
+}
+
+/* Improve the scrollbar display on firefox */
+* {
+	scrollbar-width: initial;
+	scrollbar-color: var(--scrollbar-color);
+}
+.sidebar {
+	scrollbar-width: thin;
+	scrollbar-color: var(--scrollbar-color);
+}
+
+/* Improve the scrollbar display on webkit-based browsers */
+::-webkit-scrollbar {
+	width: 12px;
+}
+.sidebar::-webkit-scrollbar {
+	width: 8px;
+}
+::-webkit-scrollbar-track {
+	-webkit-box-shadow: inset 0;
+	background-color: var(--scrollbar-track-background-color);
+}
+.sidebar::-webkit-scrollbar-track {
+	background-color: var(--scrollbar-track-background-color);
+}
+::-webkit-scrollbar-thumb, .sidebar::-webkit-scrollbar-thumb {
+	background-color: var(--scrollbar-thumb-background-color);
+}
+
+/* Everything else */
+
+.hidden {
+	display: none !important;
+}
+
+.sidebar .logo-container {
+	display: flex;
+	margin-top: 10px;
+	margin-bottom: 10px;
+	justify-content: center;
+}
+
+.version {
+	overflow-wrap: break-word;
+}
+
+.logo-container > img {
+	height: 100px;
+	width: 100px;
+}
+
+.location:empty {
+	border: none;
+}
+
+.location a:first-of-type {
+	font-weight: 500;
+}
+
+.block {
+	padding: 0;
+}
+.block ul, .block li {
+	padding: 0;
+	margin: 0;
+	list-style: none;
+}
+
+.block a,
+h2.location a {
+	display: block;
+	padding: 0.25rem;
+	margin-left: -0.25rem;
+
+	text-overflow: ellipsis;
+	overflow: hidden;
+}
+
+.sidebar h2 {
+	border-bottom: none;
+	font-weight: 500;
+	padding: 0;
+	margin: 0;
+	margin-top: 0.7rem;
+	margin-bottom: 0.7rem;
+}
+
+.sidebar h3 {
+	font-size: 1.125rem; /* 18px */
+	font-weight: 500;
+	padding: 0;
+	margin: 0;
+}
+
+.sidebar-elems .block {
+	margin-bottom: 2em;
+}
+
+.sidebar-elems .block li a {
+	white-space: nowrap;
+}
+
+.mobile-topbar {
+	display: none;
+}
+
+.source .content pre.rust {
+	white-space: pre;
+	overflow: auto;
+	padding-left: 0;
+}
+
+.rustdoc .example-wrap {
+	display: inline-flex;
+	margin-bottom: 10px;
+}
+
+.example-wrap {
+	position: relative;
+	width: 100%;
+}
+
+.example-wrap > pre.line-number {
+	overflow: initial;
+	border: 1px solid;
+	padding: 13px 8px;
+	text-align: right;
+	border-top-left-radius: 5px;
+	border-bottom-left-radius: 5px;
+}
+
+.example-wrap > pre.rust a:hover {
+	text-decoration: underline;
+}
+
+.line-numbers {
+	text-align: right;
+}
+.rustdoc:not(.source) .example-wrap > pre:not(.line-number) {
+	width: 100%;
+	overflow-x: auto;
+}
+
+.rustdoc:not(.source) .example-wrap > pre.line-numbers {
+	width: auto;
+	overflow-x: visible;
+}
+
+.rustdoc .example-wrap > pre {
+	margin: 0;
+}
+
+#search {
+	position: relative;
+}
+
+.search-loading {
+	text-align: center;
+}
+
+#results > table {
+	width: 100%;
+	table-layout: fixed;
+}
+
+.content > .example-wrap pre.line-numbers {
+	position: relative;
+	-webkit-user-select: none;
+	-moz-user-select: none;
+	-ms-user-select: none;
+	user-select: none;
+}
+.line-numbers span {
+	cursor: pointer;
+}
+
+.docblock-short {
+	overflow-wrap: break-word;
+	overflow-wrap: anywhere;
+}
+.docblock-short p {
+	display: inline;
+}
+
+.docblock-short p {
+	overflow: hidden;
+	text-overflow: ellipsis;
+	margin: 0;
+}
+/* Wrap non-pre code blocks (`text`) but not (```text```). */
+.docblock > :not(pre) > code,
+.docblock-short > :not(pre) > code {
+	white-space: pre-wrap;
+}
+
+.top-doc .docblock h2 { font-size: 1.375rem; }
+.top-doc .docblock h3 { font-size: 1.25rem; }
+.top-doc .docblock h4,
+.top-doc .docblock h5 {
+	font-size: 1.125rem;
+}
+.top-doc .docblock h6 {
+	font-size: 1rem;
+}
+
+.docblock h5 { font-size: 1rem; }
+.docblock h6 { font-size: 0.875rem; }
+.docblock h1, .docblock h2, .docblock h3, .docblock h4, .docblock h5, .docblock h6 {
+	border-bottom-color: var(--headings-border-bottom-color);
+}
+
+.docblock {
+	margin-left: 24px;
+	position: relative;
+}
+
+.docblock > :not(.information):not(.more-examples-toggle) {
+	max-width: 100%;
+	overflow-x: auto;
+}
+
+.content .out-of-band {
+	flex-grow: 0;
+	font-size: 1.125rem;
+	font-weight: normal;
+	float: right;
+}
+
+.method > .code-header, .trait-impl > .code-header {
+	max-width: calc(100% - 41px);
+	display: block;
+}
+
+.content .in-band {
+	flex-grow: 1;
+	margin: 0px;
+	padding: 0px;
+	overflow-wrap: break-word;
+	overflow-wrap: anywhere;
+}
+
+.in-band > code, .in-band > .code-header {
+	display: inline-block;
+}
+
+.docblock code, .docblock-short code,
+pre, .rustdoc.source .example-wrap {
+	background-color: var(--code-block-background-color);
+}
+
+#main-content {
+	position: relative;
+}
+#main-content > .since {
+	top: inherit;
+}
+
+.content table:not(.table-display) {
+	border-spacing: 0 5px;
+}
+.content td { vertical-align: top; }
+.content td:first-child { padding-right: 20px; }
+.content td p:first-child { margin-top: 0; }
+.content td h1, .content td h2 { margin-left: 0; font-size: 1.125rem; }
+.content tr:first-child td { border-top: 0; }
+
+.docblock table {
+	margin: .5em 0;
+	width: calc(100% - 2px);
+	overflow-x: auto;
+	display: block;
+}
+
+.docblock table td {
+	padding: .5em;
+	border: 1px dashed;
+}
+
+.docblock table th {
+	padding: .5em;
+	text-align: left;
+	border: 1px solid;
+}
+
+.fields + table {
+	margin-bottom: 1em;
+}
+
+.content .item-list {
+	list-style-type: none;
+	padding: 0;
+}
+
+.content .multi-column {
+	-moz-column-count: 5;
+	-moz-column-gap: 2.5em;
+	-webkit-column-count: 5;
+	-webkit-column-gap: 2.5em;
+	column-count: 5;
+	column-gap: 2.5em;
+}
+.content .multi-column li { width: 100%; display: inline-block; }
+
+.content > .methods > .method {
+	font-size: 1rem;
+	position: relative;
+}
+/* Shift "where ..." part of method or fn definition down a line */
+.content .method .where,
+.content .fn .where,
+.content .where.fmt-newline {
+	display: block;
+	font-size: 0.875rem;
+}
+
+.content .methods > div:not(.notable-traits):not(.method) {
+	margin-left: 40px;
+	margin-bottom: 15px;
+}
+
+.content .docblock > .impl-items {
+	margin-left: 20px;
+	margin-top: -34px;
+}
+.content .docblock >.impl-items .table-display {
+	margin: 0;
+}
+.content .docblock >.impl-items table td {
+	padding: 0;
+}
+.content .docblock > .impl-items .table-display, .impl-items table td {
+	border: none;
+}
+
+.item-info {
+	display: block;
+}
+
+.content .item-info code {
+	font-size: 0.875rem;
+}
+
+.content .item-info {
+	position: relative;
+	margin-left: 24px;
+}
+
+.sub-variant > div > .item-info {
+	margin-top: initial;
+}
+
+.content .impl-items .docblock, .content .impl-items .item-info {
+	margin-bottom: .6em;
+}
+
+.content .impl-items > .item-info {
+	margin-left: 40px;
+}
+
+.methods > .item-info, .content .impl-items > .item-info {
+	margin-top: -8px;
+}
+
+.impl-items {
+	flex-basis: 100%;
+}
+
+#main-content > .item-info {
+	margin-top: 0;
+	margin-left: 0;
+}
+
+nav.sub {
+	flex-grow: 1;
+	margin-bottom: 25px;
+}
+.source nav.sub {
+	margin-left: 32px;
+}
+nav.main {
+	padding: 20px 0;
+	text-align: center;
+}
+nav.main .current {
+	border-top: 1px solid;
+	border-bottom: 1px solid;
+}
+nav.main .separator {
+	border: 1px solid;
+	display: inline-block;
+	height: 23px;
+	margin: 0 20px;
+}
+nav.sum { text-align: right; }
+nav.sub form { display: inline; }
+
+a {
+	text-decoration: none;
+	background: transparent;
+}
+
+.small-section-header {
+	display: flex;
+	justify-content: space-between;
+	position: relative;
+}
+
+.small-section-header:hover > .anchor {
+	display: initial;
+}
+
+.in-band:hover > .anchor, .impl:hover > .anchor, .method.trait-impl:hover > .anchor,
+.type.trait-impl:hover > .anchor, .associatedconstant.trait-impl:hover > .anchor,
+.associatedtype.trait-impl:hover > .anchor {
+	display: inline-block;
+	position: absolute;
+}
+.anchor {
+	display: none;
+	position: absolute;
+	left: -0.5em;
+	background: none !important;
+}
+.anchor.field {
+	left: -5px;
+}
+.small-section-header > .anchor {
+	left: -15px;
+	padding-right: 8px;
+}
+h2.small-section-header > .anchor {
+	padding-right: 6px;
+}
+.anchor::before {
+	content: '§';
+}
+
+.docblock a:not(.srclink):not(.test-arrow):not(.scrape-help):hover,
+.docblock-short a:not(.srclink):not(.test-arrow):not(.scrape-help):hover, .item-info a {
+	text-decoration: underline;
+}
+
+.block a.current.crate { font-weight: 500; }
+
+/*  In most contexts we use `overflow-wrap: anywhere` to ensure that we can wrap
+	as much as needed on mobile (see
+	src/test/rustdoc-gui/type-declaration-overflow.goml for an example of why
+	this matters). The `anywhere` value means:
+
+	"Soft wrap opportunities introduced by the word break are considered when
+	 calculating min-content intrinsic sizes."
+
+	https://developer.mozilla.org/en-US/docs/Web/CSS/overflow-wrap#values
+
+	For table layouts, that becomes a problem: the browser tries to make each
+	column as narrow as possible, and `overflow-wrap: anywhere` means it can do
+	so by breaking words - even if some other column could be shrunk without
+	breaking words! This shows up, for instance, in the `Structs` / `Modules` /
+	`Functions` (etcetera) sections of a module page, and when a docblock
+	contains a table.
+
+	So, for table layouts, override the default with break-word, which does
+	_not_ affect min-content intrinsic sizes.
+*/
+table,
+.item-table {
+	overflow-wrap: break-word;
+}
+
+.item-table {
+	display: table;
+}
+.item-row {
+	display: table-row;
+}
+.item-left, .item-right {
+	display: table-cell;
+}
+.item-left {
+	padding-right: 1.25rem;
+}
+
+.search-container {
+	position: relative;
+	display: flex;
+	height: 34px;
+}
+.search-container > * {
+	height: 100%;
+}
+.search-results-title {
+	display: inline;
+}
+#search-settings {
+	font-size: 1.5rem;
+	font-weight: 500;
+	margin-bottom: 20px;
+}
+#crate-search {
+	min-width: 115px;
+	margin-top: 5px;
+	padding-left: 0.15em;
+	padding-right: 23px;
+	border: 1px solid;
+	border-radius: 4px;
+	outline: none;
+	cursor: pointer;
+	-moz-appearance: none;
+	-webkit-appearance: none;
+	/* Removes default arrow from firefox */
+	background-repeat: no-repeat;
+	background-color: transparent;
+	background-size: 20px;
+	background-position: calc(100% - 1px) 56%;
+	background-image: /* AUTOREPLACE: */url("down-arrow.svg");
+	max-width: 100%;
+	text-overflow: ellipsis;
+}
+.search-container {
+	margin-top: 4px;
+}
+.search-input {
+	/* Override Normalize.css: it has a rule that sets
+	   -webkit-appearance: textfield for search inputs. That
+	   causes rounded corners and no border on iOS Safari. */
+	-webkit-appearance: none;
+	/* Override Normalize.css: we have margins and do
+	 not want to overflow - the `moz` attribute is necessary
+	 until Firefox 29, too early to drop at this point */
+	-moz-box-sizing: border-box !important;
+	box-sizing: border-box !important;
+	outline: none;
+	border: 1px solid;
+	border-radius: 2px;
+	padding: 8px;
+	font-size: 1rem;
+	width: 100%;
+}
+
+.search-results {
+	display: none;
+	padding-bottom: 2em;
+}
+
+.search-results.active {
+	display: block;
+	/* prevent overhanging tabs from moving the first result */
+	clear: both;
+}
+
+.search-results .desc > span {
+	white-space: nowrap;
+	text-overflow: ellipsis;
+	overflow: hidden;
+	display: block;
+}
+
+.search-results > a {
+	display: block;
+	width: 100%;
+	/* A little margin ensures the browser's outlining of focused links has room to display. */
+	margin-left: 2px;
+	margin-right: 2px;
+	border-bottom: 1px solid #aaa3;
+}
+
+.search-results > a > div {
+	display: flex;
+	flex-flow: row wrap;
+}
+
+.search-results .result-name, .search-results div.desc, .search-results .result-description {
+	width: 50%;
+}
+.search-results .result-name {
+	padding-right: 1em;
+}
+
+.search-results .result-name > span {
+	display: inline-block;
+	margin: 0;
+	font-weight: normal;
+}
+
+.popover {
+	font-size: 1rem;
+	position: absolute;
+	right: 0;
+	z-index: 2;
+	display: block;
+	margin-top: 7px;
+	border-radius: 3px;
+	border: 1px solid;
+	font-size: 1rem;
+}
+
+/* This rule is to draw the little arrow connecting the settings menu to the gear icon. */
+.popover::before {
+	content: '';
+	position: absolute;
+	right: 11px;
+	border: solid;
+	border-width: 1px 1px 0 0;
+	display: inline-block;
+	padding: 4px;
+	transform: rotate(-45deg);
+	top: -5px;
+}
+
+.popover, .popover::before {
+	background-color: var(--main-background-color);
+	color: var(--main-color);
+}
+
+#help-button .popover {
+	max-width: 600px;
+}
+
+#help-button .popover::before {
+	right: 48px;
+}
+
+#help-button dt {
+	float: left;
+	clear: left;
+	display: block;
+	margin-right: 0.5rem;
+}
+#help-button span.top, #help-button span.bottom {
+	text-align: center;
+	display: block;
+	font-size: 1.125rem;
+}
+#help-button span.top {
+	text-align: center;
+	display: block;
+	margin: 10px 0;
+	border-bottom: 1px solid;
+	padding-bottom: 4px;
+	margin-bottom: 6px;
+}
+#help-button span.bottom {
+	clear: both;
+	border-top: 1px solid;
+}
+.side-by-side {
+	text-align: initial;
+}
+.side-by-side > div {
+	width: 50%;
+	float: left;
+	padding: 0 20px 20px 17px;
+}
+
+.item-info .stab {
+	width: fit-content;
+	/* This min-height is needed to unify the height of the stab elements because some of them
+	   have emojis.
+	*/
+	min-height: 36px;
+	display: flex;
+	align-items: center;
+	white-space: pre-wrap;
+}
+.stab {
+	padding: 3px;
+	margin-bottom: 5px;
+	font-size: 0.875rem;
+	font-weight: normal;
+}
+.stab p {
+	display: inline;
+	margin: 0;
+}
+
+.stab .emoji {
+	font-size: 1.25rem;
+}
+
+/* Black one-pixel outline around emoji shapes */
+.emoji {
+	text-shadow:
+		1px 0 0 black,
+		-1px 0 0 black,
+		0  1px 0 black,
+		0 -1px 0 black;
+}
+
+.module-item .stab,
+.import-item .stab {
+	border-radius: 3px;
+	display: inline-block;
+	font-size: 0.875rem;
+	line-height: 1.2;
+	margin-bottom: 0;
+	margin-left: 0.3125em;
+	padding: 2px;
+	vertical-align: text-bottom;
+}
+
+.module-item.unstable,
+.import-item.unstable {
+	opacity: 0.65;
+}
+
+.since {
+	font-weight: normal;
+	font-size: initial;
+}
+
+.rightside {
+	padding-left: 12px;
+	padding-right: 2px;
+	position: initial;
+}
+
+.impl-items .srclink, .impl .srclink, .methods .srclink {
+	/* Override header settings otherwise it's too bold */
+	font-weight: normal;
+	font-size: 1rem;
+}
+
+.rightside {
+	float: right;
+}
+
+.variants_table {
+	width: 100%;
+}
+
+.variants_table tbody tr td:first-child {
+	width: 1%; /* make the variant name as small as possible */
+}
+
+td.summary-column {
+	width: 100%;
+}
+
+.summary {
+	padding-right: 0px;
+}
+
+pre.rust .question-mark {
+	font-weight: bold;
+}
+
+a.test-arrow {
+	display: inline-block;
+	visibility: hidden;
+	position: absolute;
+	padding: 5px 10px 5px 10px;
+	border-radius: 5px;
+	font-size: 1.375rem;
+	top: 5px;
+	right: 5px;
+	z-index: 1;
+}
+.example-wrap:hover .test-arrow {
+	visibility: visible;
+}
+a.test-arrow:hover{
+	text-decoration: none;
+}
+
+.code-attribute {
+	font-weight: 300;
+}
+
+.item-spacer {
+	width: 100%;
+	height: 12px;
+}
+
+.out-of-band > span.since {
+	position: initial;
+	font-size: 1.25rem;
+}
+
+h3.variant {
+	font-weight: 600;
+	font-size: 1.125rem;
+	margin-bottom: 10px;
+	border-bottom: none;
+}
+
+.sub-variant h4 {
+	font-size: 1rem;
+	font-weight: 400;
+	border-bottom: none;
+	margin-top: 0;
+	margin-bottom: 0;
+}
+
+.sub-variant {
+	margin-left: 24px;
+	margin-bottom: 40px;
+}
+
+.sub-variant > .sub-variant-field {
+	margin-left: 24px;
+}
+
+.toggle-label {
+	display: inline-block;
+	margin-left: 4px;
+	margin-top: 3px;
+}
+
+:target > code, :target > .code-header {
+	opacity: 1;
+}
+
+:target {
+	padding-right: 3px;
+}
+
+.information {
+	position: absolute;
+	left: -25px;
+	margin-top: 7px;
+	z-index: 1;
+}
+
+.tooltip {
+	position: relative;
+	display: inline-block;
+	cursor: pointer;
+}
+
+.tooltip::after {
+	display: none;
+	text-align: center;
+	padding: 5px 3px 3px 3px;
+	border-radius: 6px;
+	margin-left: 5px;
+	font-size: 1rem;
+}
+
+.tooltip.ignore::after {
+	content: "This example is not tested";
+}
+.tooltip.compile_fail::after {
+	content: "This example deliberately fails to compile";
+}
+.tooltip.should_panic::after {
+	content: "This example panics";
+}
+.tooltip.edition::after {
+	content: "This code runs with edition " attr(data-edition);
+}
+
+.tooltip::before {
+	content: " ";
+	position: absolute;
+	top: 50%;
+	left: 16px;
+	margin-top: -5px;
+	border-width: 5px;
+	border-style: solid;
+	display: none;
+}
+
+.tooltip:hover::before, .tooltip:hover::after {
+	display: inline;
+}
+
+.tooltip.compile_fail, .tooltip.should_panic, .tooltip.ignore {
+	font-weight: bold;
+	font-size: 1.25rem;
+}
+
+.notable-traits-tooltip {
+	display: inline-block;
+	cursor: pointer;
+}
+
+.notable-traits:hover .notable-traits-tooltiptext,
+.notable-traits .notable-traits-tooltiptext.force-tooltip {
+	display: inline-block;
+}
+
+.notable-traits .notable-traits-tooltiptext {
+	display: none;
+	padding: 5px 3px 3px 3px;
+	border-radius: 6px;
+	margin-left: 5px;
+	z-index: 10;
+	font-size: 1rem;
+	cursor: default;
+	position: absolute;
+	border: 1px solid;
+}
+
+.notable-traits-tooltip::after {
+	/* The margin on the tooltip does not capture hover events,
+	   this extends the area of hover enough so that mouse hover is not
+	   lost when moving the mouse to the tooltip */
+	content: "\00a0\00a0\00a0";
+}
+
+.notable-traits .notable, .notable-traits .docblock {
+	margin: 0;
+}
+
+.notable-traits .notable {
+	margin: 0;
+	margin-bottom: 13px;
+	font-size: 1.1875rem;
+	font-weight: 600;
+	display: block;
+}
+
+.notable-traits .docblock code.content{
+	margin: 0;
+	padding: 0;
+	font-size: 1.25rem;
+}
+
+/* Example code has the "Run" button that needs to be positioned relative to the pre */
+pre.rust.rust-example-rendered {
+	position: relative;
+}
+
+pre.rust {
+	tab-size: 4;
+	-moz-tab-size: 4;
+}
+
+.search-failed {
+	text-align: center;
+	margin-top: 20px;
+	display: none;
+}
+
+.search-failed.active {
+	display: block;
+}
+
+.search-failed > ul {
+	text-align: left;
+	max-width: 570px;
+	margin-left: auto;
+	margin-right: auto;
+}
+
+#titles {
+	height: 35px;
+}
+
+#titles > button {
+	float: left;
+	width: 33.3%;
+	text-align: center;
+	font-size: 1.125rem;
+	cursor: pointer;
+	border: 0;
+	border-top: 2px solid;
+}
+
+#titles > button:first-child:last-child {
+	margin-right: 1px;
+	width: calc(100% - 1px);
+}
+
+#titles > button:not(:last-child) {
+	margin-right: 1px;
+	width: calc(33.3% - 1px);
+}
+
+#titles > button > div.count {
+	display: inline-block;
+	font-size: 1rem;
+}
+
+.notable-traits {
+	cursor: pointer;
+	z-index: 2;
+	margin-left: 5px;
+}
+
+#sidebar-toggle {
+	position: sticky;
+	top: 0;
+	left: 0;
+	font-weight: bold;
+	font-size: 1.25rem;
+	border-bottom: 1px solid;
+	display: flex;
+	height: 40px;
+	justify-content: center;
+	align-items: center;
+	z-index: 10;
+}
+#source-sidebar {
+	width: 100%;
+	z-index: 1;
+	overflow: auto;
+}
+#source-sidebar > .title {
+	font-size: 1.5rem;
+	text-align: center;
+	border-bottom: 1px solid;
+	margin-bottom: 6px;
+}
+#sidebar-toggle > button {
+	background: none;
+	color: inherit;
+	cursor: pointer;
+	text-align: center;
+	border: none;
+	outline: none;
+	position: absolute;
+	top: 0;
+	bottom: 0;
+	left: 0;
+	right: 0;
+	/* work around button layout strangeness: https://stackoverflow.com/q/7271561 */
+	width: 100%;
+	/* iOS button gradient: https://stackoverflow.com/q/5438567 */
+	-webkit-appearance: none;
+	opacity: 1;
+}
+#settings-menu, #help-button {
+	margin-left: 4px;
+	outline: none;
+}
+
+#copy-path {
+	height: 34px;
+}
+#settings-menu > a, #help-button > button, #copy-path {
+	padding: 5px;
+	width: 33px;
+	border: 1px solid;
+	border-radius: 2px;
+	cursor: pointer;
+}
+#settings-menu {
+	padding: 0;
+}
+#settings-menu > a, #help-button > button {
+	padding: 5px;
+	height: 100%;
+	display: block;
+}
+
+@keyframes rotating {
+	from {
+		transform: rotate(0deg);
+	}
+	to {
+		transform: rotate(360deg);
+	}
+}
+#settings-menu.rotate > a img {
+	animation: rotating 2s linear infinite;
+}
+
+.setting-line .radio-line input:checked {
+	box-shadow: inset 0 0 0 3px var(--main-background-color);
+	background-color: var(--settings-input-color);
+}
+.setting-line .radio-line input:focus {
+	box-shadow: 0 0 1px 1px var(--settings-input-color);
+}
+/* In here we combine both `:focus` and `:checked` properties. */
+.setting-line .radio-line input:checked:focus {
+	box-shadow: inset 0 0 0 3px var(--main-background-color),
+		0 0 2px 2px var(--settings-input-color);
+}
+.setting-line .radio-line input:hover {
+	border-color: var(--settings-input-color) !important;
+}
+input:checked + .slider {
+	background-color: var(--settings-input-color);
+}
+
+#help-button > button {
+	text-align: center;
+	/* Rare exception to specifying font sizes in rem. Since this is acting
+	   as an icon, it's okay to specify their sizes in pixels. */
+	font-size: 20px;
+	padding-top: 2px;
+}
+
+#copy-path {
+	background: initial;
+	margin-left: 10px;
+	padding: 0;
+	padding-left: 2px;
+	border: 0;
+}
+
+#theme-choices {
+	display: none;
+	position: absolute;
+	left: 0;
+	top: 28px;
+	border: 1px solid;
+	border-radius: 3px;
+	z-index: 1;
+	cursor: pointer;
+}
+
+#theme-choices > button {
+	border: none;
+	width: 100%;
+	padding: 4px 8px;
+	text-align: center;
+	background: rgba(0,0,0,0);
+	overflow-wrap: normal;
+}
+
+#theme-choices > button:not(:first-child) {
+	border-top: 1px solid;
+}
+
+kbd {
+	display: inline-block;
+	padding: 3px 5px;
+	font: 15px monospace;
+	line-height: 10px;
+	vertical-align: middle;
+	border: solid 1px;
+	border-radius: 3px;
+	cursor: default;
+}
+
+.hidden-by-impl-hider,
+.hidden-by-usual-hider {
+	/* important because of conflicting rule for small screens */
+	display: none !important;
+}
+
+#implementations-list > h3 > span.in-band {
+	width: 100%;
+}
+
+.table-display {
+	width: 100%;
+	border: 0;
+	border-collapse: collapse;
+	border-spacing: 0;
+	font-size: 1rem;
+}
+
+.table-display tr td:first-child {
+	padding-right: 0;
+}
+
+.table-display tr td:last-child {
+	float: right;
+}
+.table-display .out-of-band {
+	position: relative;
+	font-size: 1.125rem;
+	display: block;
+}
+
+.table-display td:hover .anchor {
+	display: block;
+	top: 2px;
+	left: -5px;
+}
+
+#main-content > ul {
+	padding-left: 10px;
+}
+#main-content > ul > li {
+	list-style: none;
+}
+
+.non-exhaustive {
+	margin-bottom: 1em;
+}
+
+details.dir-entry {
+	padding-left: 4px;
+}
+
+details.dir-entry > summary {
+	margin: 0 0 0 13px;
+	list-style-position: outside;
+	cursor: pointer;
+}
+
+details.dir-entry div.folders, details.dir-entry div.files {
+	padding-left: 23px;
+}
+
+details.dir-entry a {
+	display: block;
+}
+
+/* The hideme class is used on summary tags that contain a span with
+	placeholder text shown only when the toggle is closed. For instance,
+	"Expand description" or "Show methods". */
+details.rustdoc-toggle > summary.hideme {
+	cursor: pointer;
+}
+
+details.rustdoc-toggle > summary {
+	list-style: none;
+}
+details.rustdoc-toggle > summary::-webkit-details-marker,
+details.rustdoc-toggle > summary::marker {
+	display: none;
+}
+
+details.rustdoc-toggle > summary.hideme > span {
+	margin-left: 9px;
+}
+
+details.rustdoc-toggle > summary::before {
+	content: "";
+	cursor: pointer;
+	width: 16px;
+	height: 16px;
+	background-repeat: no-repeat;
+	background-position: top left;
+	display: inline-block;
+	vertical-align: middle;
+	opacity: .5;
+}
+
+/* Screen readers see the text version at the end the line.
+	Visual readers see the icon at the start of the line, but small and transparent. */
+details.rustdoc-toggle > summary::after {
+	content: "Expand";
+	overflow: hidden;
+	width: 0;
+	height: 0;
+	position: absolute;
+}
+
+details.rustdoc-toggle > summary.hideme::after {
+	/* "hideme" toggles already have a description when they're contracted */
+	content: "";
+}
+
+details.rustdoc-toggle > summary:focus::before,
+details.rustdoc-toggle > summary:hover::before {
+	opacity: 1;
+}
+
+details.rustdoc-toggle.top-doc > summary,
+details.rustdoc-toggle.top-doc > summary::before,
+details.rustdoc-toggle.non-exhaustive > summary,
+details.rustdoc-toggle.non-exhaustive > summary::before {
+	font-size: 1rem;
+}
+
+details.non-exhaustive {
+	margin-bottom: 8px;
+}
+
+details.rustdoc-toggle > summary.hideme::before {
+	position: relative;
+}
+
+details.rustdoc-toggle > summary:not(.hideme)::before {
+	position: absolute;
+	left: -24px;
+	top: 4px;
+}
+
+.impl-items > details.rustdoc-toggle > summary:not(.hideme)::before {
+	position: absolute;
+	left: -24px;
+}
+
+/* When a "hideme" summary is open and the "Expand description" or "Show
+	methods" text is hidden, we want the [-] toggle that remains to not
+	affect the layout of the items to its right. To do that, we use
+	absolute positioning. Note that we also set position: relative
+	on the parent 
     to make this work properly. */
+details.rustdoc-toggle[open] > summary.hideme {
+	position: absolute;
+}
+
+details.rustdoc-toggle {
+	position: relative;
+}
+
+details.rustdoc-toggle[open] > summary.hideme > span {
+	display: none;
+}
+
+details.rustdoc-toggle[open] > summary::before,
+details.rustdoc-toggle[open] > summary.hideme::before {
+	background-image: /* AUTOREPLACE: */url("toggle-minus.svg");
+}
+
+details.rustdoc-toggle > summary::before {
+	background-image: /* AUTOREPLACE: */url("toggle-plus.svg");
+}
+
+details.rustdoc-toggle[open] > summary::before,
+details.rustdoc-toggle[open] > summary.hideme::before {
+	width: 16px;
+	height: 16px;
+	background-repeat: no-repeat;
+	background-position: top left;
+	display: inline-block;
+	content: "";
+}
+
+details.rustdoc-toggle[open] > summary::after,
+details.rustdoc-toggle[open] > summary.hideme::after {
+	content: "Collapse";
+}
+
+/* This is needed in docblocks to have the "▶" element to be on the same line. */
+.docblock summary > * {
+	display: inline-block;
+}
+
+/* Media Queries */
+
+/*
+WARNING: RUSTDOC_MOBILE_BREAKPOINT MEDIA QUERY;
+If you update this line, then you also need to update the line with the same warning
+in storage.js plus the media query with (max-width: 700px)
+*/
+@media (min-width: 701px) {
+	/* In case there is no documentation before a code block, we need to add some margin at the top
+	to prevent an overlay between the "collapse toggle" and the information tooltip.
+	However, it's not needed with smaller screen width because the doc/code block is always put
+	"one line" below. */
+	.docblock > .information:first-child > .tooltip {
+		margin-top: 16px;
+	}
+
+	/* When we expand the sidebar on the source code page, we hide the logo on the left of the
+	search bar to have more space. */
+	.source-sidebar-expanded .source .sidebar + main .width-limiter .sub-logo-container.rust-logo {
+		display: none;
+	}
+
+	.source-sidebar-expanded .source .sidebar {
+		width: 300px;
+	}
+}
+
+/*
+WARNING: RUSTDOC_MOBILE_BREAKPOINT MEDIA QUERY
+If you update this line, then you also need to update the line with the same warning
+in storage.js plus the media query with (min-width: 701px)
+*/
+@media (max-width: 700px) {
+	/* When linking to an item with an `id` (for instance, by clicking a link in the sidebar,
+	   or visiting a URL with a fragment like `#method.new`, we don't want the item to be obscured
+	   by the topbar. Anything with an `id` gets scroll-margin-top equal to .mobile-topbar's size.
+	*/
+	*[id] {
+		scroll-margin-top: 45px;
+	}
+
+	.rustdoc {
+		padding-top: 0px;
+		/* Sidebar should overlay main content, rather than pushing main content to the right.
+		   Turn off `display: flex` on the body element. */
+		display: block;
+	}
+
+	main {
+		padding-left: 15px;
+		padding-top: 0px;
+	}
+
+	.rustdoc,
+	.main-heading {
+		flex-direction: column;
+	}
+
+	.content .out-of-band {
+		text-align: left;
+		margin-left: initial;
+		padding: initial;
+	}
+
+	.content .out-of-band .since::before {
+		content: "Since ";
+	}
+
+	#copy-path {
+		display: none;
+	}
+
+	/* Hide the logo and item name from the sidebar. Those are displayed
+	   in the mobile-topbar instead. */
+	.sidebar .sidebar-logo,
+	.sidebar .location {
+		display: none;
+	}
+
+	.sidebar-elems {
+		margin-top: 1em;
+	}
+
+	.sidebar {
+		position: fixed;
+		top: 45px;
+		/* Hide the sidebar offscreen while not in use. Doing this instead of display: none means
+		   the sidebar stays visible for screen readers, which is useful for navigation. */
+		left: -1000px;
+		margin-left: 0;
+		margin: 0;
+		padding: 0;
+		z-index: 11;
+		/* Reduce height slightly to account for mobile topbar. */
+		height: calc(100vh - 45px);
+	}
+
+	/* The source view uses a different design for the sidebar toggle, and doesn't have a topbar,
+	   so don't bump down the main content or the sidebar. */
+	.source main,
+	.rustdoc.source .sidebar {
+		top: 0;
+		padding: 0;
+		height: 100vh;
+		border: 0;
+	}
+
+	.sidebar.shown,
+	.source-sidebar-expanded .source .sidebar,
+	.sidebar:focus-within {
+		left: 0;
+	}
+
+	.rustdoc.source > .sidebar {
+		position: fixed;
+		margin: 0;
+		z-index: 11;
+		width: 0;
+	}
+
+	.mobile-topbar .location a {
+		padding: 0;
+		margin: 0;
+	}
+
+	.mobile-topbar .location {
+		border: none;
+		padding: 0;
+		margin: auto 0.5em auto auto;
+		text-overflow: ellipsis;
+		overflow: hidden;
+		white-space: nowrap;
+		/* Rare exception to specifying font sizes in rem. Since the topbar
+		   height is specified in pixels, this also has to be specified in
+		   pixels to avoid overflowing the topbar when the user sets a bigger
+		   font size. */
+		font-size: 24px;
+	}
+
+	.mobile-topbar .logo-container {
+		max-height: 45px;
+	}
+
+	.mobile-topbar .logo-container > img {
+		max-width: 35px;
+		max-height: 35px;
+		margin-left: 20px;
+		margin-top: 5px;
+		margin-bottom: 5px;
+	}
+
+	.mobile-topbar {
+		display: flex;
+		flex-direction: row;
+		position: sticky;
+		z-index: 10;
+		font-size: 2rem;
+		height: 45px;
+		width: 100%;
+		left: 0;
+		top: 0;
+	}
+
+	.source .mobile-topbar {
+		display: none;
+	}
+
+	.sidebar-menu-toggle {
+		width: 45px;
+		/* Rare exception to specifying font sizes in rem. Since this is acting
+		   as an icon, it's okay to specify its sizes in pixels. */
+		font-size: 32px;
+		border: none;
+	}
+
+	.sidebar-elems {
+		background-color: var(--sidebar-background-color);
+	}
+
+	.source nav:not(.sidebar).sub {
+		margin-left: 32px;
+	}
+
+	.content {
+		margin-left: 0px;
+	}
+
+	.source .content {
+		margin-top: 10px;
+	}
+
+	#search {
+		margin-left: 0;
+		padding: 0;
+	}
+
+	.anchor {
+		display: none !important;
+	}
+
+	.notable-traits {
+		position: absolute;
+		left: -22px;
+		top: 24px;
+	}
+
+	#titles > button > div.count {
+		float: left;
+		width: 100%;
+	}
+
+	#titles {
+		height: 50px;
+	}
+
+	/* Because of ios, we need to actually have a full height sidebar title so the
+	 * actual sidebar can show up. But then we need to make it transparent so we don't
+	 * hide content. The filler just allows to create the background for the sidebar
+	 * title. But because of the absolute position, I had to lower the z-index.
+	 */
+	#sidebar-filler {
+		position: fixed;
+		left: 45px;
+		width: calc(100% - 45px);
+		top: 0;
+		height: 45px;
+		z-index: -1;
+		border-bottom: 1px solid;
+	}
+
+	#main-content > details.rustdoc-toggle > summary::before,
+	#main-content > div > details.rustdoc-toggle > summary::before {
+		left: -11px;
+	}
+
+	#sidebar-toggle {
+		position: fixed;
+		left: 1px;
+		top: 100px;
+		width: 30px;
+		font-size: 1.5rem;
+		text-align: center;
+		padding: 0;
+		z-index: 10;
+		border-top-right-radius: 3px;
+		border-bottom-right-radius: 3px;
+		cursor: pointer;
+		font-weight: bold;
+		border: 1px solid;
+		border-left: 0;
+	}
+
+	.source-sidebar-expanded #sidebar-toggle {
+		left: unset;
+		top: unset;
+		width: unset;
+		border-top-right-radius: unset;
+		border-bottom-right-radius: unset;
+		position: sticky;
+		border: 0;
+		border-bottom: 1px solid;
+	}
+
+	#source-sidebar {
+		z-index: 11;
+	}
+
+	#main-content > .line-numbers {
+		margin-top: 0;
+	}
+
+	.notable-traits .notable-traits-tooltiptext {
+		left: 0;
+		top: 100%;
+	}
+
+	/* We don't display the help button on mobile devices. */
+	#help-button {
+		display: none;
+	}
+
+	/* Display an alternating layout on tablets and phones */
+	.item-table {
+		display: block;
+	}
+	.item-row {
+		display: flex;
+		flex-flow: column wrap;
+	}
+	.item-left, .item-right {
+		width: 100%;
+	}
+
+	/* Display an alternating layout on tablets and phones */
+	.search-results > a {
+		border-bottom: 1px solid #aaa9;
+		padding: 5px 0px;
+	}
+	.search-results .result-name, .search-results div.desc, .search-results .result-description {
+		width: 100%;
+	}
+	.search-results div.desc, .search-results .result-description, .item-right {
+		padding-left: 2em;
+	}
+
+	.source-sidebar-expanded .source .sidebar {
+		max-width: 100vw;
+		width: 100vw;
+	}
+
+	/* Position of the "[-]" element. */
+	details.rustdoc-toggle:not(.top-doc) > summary {
+		margin-left: 10px;
+	}
+	.impl-items > details.rustdoc-toggle > summary:not(.hideme)::before,
+	#main-content > details.rustdoc-toggle:not(.top-doc) > summary::before,
+	#main-content > div > details.rustdoc-toggle > summary::before {
+		left: -11px;
+	}
+}
+
+@media print {
+	nav.sidebar, nav.sub, .content .out-of-band, a.srclink, #copy-path,
+	details.rustdoc-toggle[open] > summary::before, details.rustdoc-toggle > summary::before,
+	details.rustdoc-toggle.top-doc > summary {
+		display: none;
+	}
+
+	.docblock {
+		margin-left: 0;
+	}
+
+	main {
+		padding: 10px;
+	}
+}
+
+@media (max-width: 464px) {
+	#titles, #titles > button {
+		height: 73px;
+	}
+
+	#main-content > table:not(.table-display) td {
+		word-break: break-word;
+		width: 50%;
+	}
+
+	#crate-search {
+		border-radius: 4px;
+	}
+
+	.docblock {
+		margin-left: 12px;
+	}
+
+	.docblock code {
+		overflow-wrap: break-word;
+		overflow-wrap: anywhere;
+	}
+
+	.sub-container {
+		flex-direction: column;
+	}
+
+	.sub-logo-container {
+		align-self: center;
+	}
+
+	.source .sub-logo-container > img {
+		height: 35px;
+		width: 35px;
+	}
+
+	#sidebar-toggle {
+		top: 10px;
+	}
+	.source-sidebar-expanded #sidebar-toggle {
+		top: unset;
+	}
+}
+
+.method-toggle summary,
+.implementors-toggle summary,
+.impl {
+	margin-bottom: 0.75em;
+}
+
+.method-toggle[open] {
+	margin-bottom: 2em;
+}
+
+.implementors-toggle[open]  {
+	margin-bottom: 2em;
+}
+
+#trait-implementations-list .method-toggle,
+#synthetic-implementations-list .method-toggle,
+#blanket-implementations-list .method-toggle {
+	margin-bottom: 1em;
+}
+
+/* Begin: styles for --scrape-examples feature */
+
+.scraped-example-list .scrape-help {
+	margin-left: 10px;
+	padding: 0 4px;
+	font-weight: normal;
+	font-size: 12px;
+	position: relative;
+	bottom: 1px;
+	background: transparent;
+	border-width: 1px;
+	border-style: solid;
+	border-radius: 50px;
+}
+
+.scraped-example .code-wrapper {
+	position: relative;
+	display: flex;
+	flex-direction: row;
+	flex-wrap: wrap;
+	width: 100%;
+}
+
+.scraped-example:not(.expanded) .code-wrapper {
+	max-height: 240px;
+}
+
+.scraped-example:not(.expanded) .code-wrapper pre {
+	overflow-y: hidden;
+	max-height: 240px;
+	padding-bottom: 0;
+}
+
+.scraped-example:not(.expanded) .code-wrapper pre.line-numbers {
+	overflow-x: hidden;
+}
+
+.scraped-example .code-wrapper .prev {
+	position: absolute;
+	top: 0.25em;
+	right: 2.25em;
+	z-index: 100;
+	cursor: pointer;
+}
+
+.scraped-example .code-wrapper .next {
+	position: absolute;
+	top: 0.25em;
+	right: 1.25em;
+	z-index: 100;
+	cursor: pointer;
+}
+
+.scraped-example .code-wrapper .expand {
+	position: absolute;
+	top: 0.25em;
+	right: 0.25em;
+	z-index: 100;
+	cursor: pointer;
+}
+
+.scraped-example:not(.expanded) .code-wrapper:before {
+	content: " ";
+	width: 100%;
+	height: 5px;
+	position: absolute;
+	z-index: 100;
+	top: 0;
+}
+
+.scraped-example:not(.expanded) .code-wrapper:after {
+	content: " ";
+	width: 100%;
+	height: 5px;
+	position: absolute;
+	z-index: 100;
+	bottom: 0;
+}
+
+.scraped-example .code-wrapper .line-numbers {
+	margin: 0;
+	padding: 14px 0;
+}
+
+.scraped-example .code-wrapper .line-numbers span {
+	padding: 0 14px;
+}
+
+.scraped-example .code-wrapper .example-wrap {
+	flex: 1;
+	overflow-x: auto;
+	overflow-y: hidden;
+	margin-bottom: 0;
+}
+
+.scraped-example:not(.expanded) .code-wrapper .example-wrap {
+	overflow-x: hidden;
+}
+
+.scraped-example .code-wrapper .example-wrap pre.rust {
+	overflow-x: inherit;
+	width: inherit;
+	overflow-y: hidden;
+}
+
+
+.more-examples-toggle {
+	max-width: calc(100% + 25px);
+	margin-top: 10px;
+	margin-left: -25px;
+}
+
+.more-examples-toggle .hide-more {
+	margin-left: 25px;
+	margin-bottom: 5px;
+	cursor: pointer;
+}
+
+.more-scraped-examples {
+	margin-left: 5px;
+	display: flex;
+	flex-direction: row;
+}
+
+.more-scraped-examples-inner {
+	/* 20px is width of toggle-line + toggle-line-inner */
+	width: calc(100% - 20px);
+}
+
+.toggle-line {
+	align-self: stretch;
+	margin-right: 10px;
+	margin-top: 5px;
+	padding: 0 4px;
+	cursor: pointer;
+}
+
+.toggle-line-inner {
+	min-width: 2px;
+	height: 100%;
+}
+
+.more-scraped-examples .scraped-example {
+	margin-bottom: 20px;
+}
+
+.more-scraped-examples .scraped-example:last-child {
+	margin-bottom: 0;
+}
+
+.example-links a {
+	margin-top: 20px;
+}
+
+.example-links ul {
+	margin-bottom: 0;
+}
+
+/* End: styles for --scrape-examples feature */
diff --git a/src/librustdoc/html/static/css/settings.css b/src/librustdoc/html/static/css/settings.css
new file mode 100644
index 000000000..e82ec0426
--- /dev/null
+++ b/src/librustdoc/html/static/css/settings.css
@@ -0,0 +1,90 @@
+.setting-line {
+	margin: 0.6em 0 0.6em 0.3em;
+	position: relative;
+}
+
+.setting-line .choices {
+	display: flex;
+	flex-wrap: wrap;
+}
+
+.setting-line .radio-line input {
+	margin-right: 0.3em;
+	height: 1.2rem;
+	width: 1.2rem;
+	border: 1px solid;
+	outline: none;
+	-webkit-appearance: none;
+	cursor: pointer;
+	border-radius: 50%;
+}
+.setting-line .radio-line input + span {
+	padding-bottom: 1px;
+}
+
+.radio-line .setting-name {
+	width: 100%;
+}
+
+.radio-line .choice {
+	margin-top: 0.1em;
+	margin-bottom: 0.1em;
+	min-width: 3.8em;
+	padding: 0.3em;
+	display: flex;
+	align-items: center;
+	cursor: pointer;
+}
+.radio-line .choice + .choice {
+	margin-left: 0.5em;
+}
+
+.toggle {
+	position: relative;
+	width: 100%;
+	margin-right: 20px;
+	display: flex;
+	align-items: center;
+	cursor: pointer;
+}
+
+.toggle input {
+	opacity: 0;
+	position: absolute;
+}
+
+.slider {
+	position: relative;
+	width: 45px;
+	min-width: 45px;
+	display: block;
+	height: 28px;
+	margin-right: 20px;
+	cursor: pointer;
+	background-color: #ccc;
+	transition: .3s;
+}
+
+.slider:before {
+	position: absolute;
+	content: "";
+	height: 19px;
+	width: 19px;
+	left: 4px;
+	bottom: 4px;
+	transition: .3s;
+}
+
+input:checked + .slider:before {
+	transform: translateX(19px);
+}
+
+.setting-line > .sub-settings {
+	padding-left: 42px;
+	width: 100%;
+	display: block;
+}
+
+#settings .setting-line {
+	margin: 1.2em 0.6em;
+}
diff --git a/src/librustdoc/html/static/css/themes/ayu.css b/src/librustdoc/html/static/css/themes/ayu.css
new file mode 100644
index 000000000..c42cac59b
--- /dev/null
+++ b/src/librustdoc/html/static/css/themes/ayu.css
@@ -0,0 +1,563 @@
+/*
+Based off of the Ayu theme
+Original by Dempfi (https://github.com/dempfi/ayu)
+*/
+
+:root {
+	--main-background-color: #0f1419;
+	--main-color: #c5c5c5;
+	--settings-input-color: #ffb454;
+	--sidebar-background-color: #14191f;
+	--sidebar-background-color-hover: rgba(70, 70, 70, 0.33);
+	--code-block-background-color: #191f26;
+	--scrollbar-track-background-color: transparent;
+	--scrollbar-thumb-background-color: #5c6773;
+	--scrollbar-color: #5c6773 #24292f;
+	--headings-border-bottom-color: #5c6773;
+}
+
+.slider {
+	background-color: #ccc;
+}
+.slider:before {
+	background-color: white;
+}
+input:focus + .slider {
+	box-shadow: 0 0 0 2px #0a84ff, 0 0 0 6px rgba(10, 132, 255, 0.3);
+}
+
+h1, h2, h3, h4 {
+	color: white;
+}
+h1.fqn  a {
+	color: #fff;
+}
+h4 {
+	border: none;
+}
+
+.in-band {
+	background-color: #0f1419;
+}
+
+.docblock code {
+	color: #ffb454;
+}
+.code-header {
+	color: #e6e1cf;
+}
+.docblock pre > code, pre > code {
+	color: #e6e1cf;
+}
+span code {
+	color: #e6e1cf;
+}
+.docblock a > code {
+	color: #39AFD7 !important;
+}
+pre, .rustdoc.source .example-wrap {
+	color: #e6e1cf;
+}
+
+.rust-logo {
+	filter: drop-shadow(1px 0 0px #fff)
+		drop-shadow(0 1px 0 #fff)
+		drop-shadow(-1px 0 0 #fff)
+		drop-shadow(0 -1px 0 #fff);
+}
+
+.sidebar .current,
+.sidebar a:hover {
+	background-color: transparent;
+	color: #ffb44c;
+}
+
+.sidebar-elems .location {
+	color: #ff7733;
+}
+
+.line-numbers span { color: #5c6773; }
+.line-numbers .line-highlighted {
+	color: #708090;
+	background-color: rgba(255, 236, 164, 0.06);
+	padding-right: 4px;
+	border-right: 1px solid #ffb44c;
+}
+
+.docblock table td, .docblock table th {
+	border-color: #5c6773;
+}
+
+.search-results a:hover {
+	background-color: #777;
+}
+
+.search-results a:focus {
+	color: #000 !important;
+	background-color: #c6afb3;
+}
+.search-results a {
+	color: #0096cf;
+}
+.search-results a div.desc {
+	color: #c5c5c5;
+}
+
+.content .item-info::before { color: #ccc; }
+
+.content span.foreigntype, .content a.foreigntype { color: #ffa0a5; }
+.content span.union, .content a.union { color: #ffa0a5; }
+.content span.constant, .content a.constant,
+.content span.static, .content a.static { color: #39AFD7; }
+.content span.primitive, .content a.primitive { color: #ffa0a5; }
+.content span.traitalias, .content a.traitalias { color: #39AFD7; }
+.content span.keyword, .content a.keyword { color: #39AFD7; }
+
+.content span.externcrate, .content span.mod, .content a.mod {
+	color: #39AFD7;
+}
+.content span.struct, .content a.struct {
+	color: #ffa0a5;
+}
+.content span.enum, .content a.enum {
+	color: #ffa0a5;
+}
+.content span.trait, .content a.trait {
+	color: #39AFD7;
+}
+.content span.type, .content a.type {
+	color: #39AFD7;
+}
+.content span.type,
+.content a.type,
+.block a.current.type { color: #39AFD7; }
+.content span.associatedtype,
+.content a.associatedtype,
+.block a.current.associatedtype { color: #39AFD7; }
+.content span.fn, .content a.fn, .content span.method,
+.content a.method, .content span.tymethod,
+.content a.tymethod, .content .fnname {
+	color: #fdd687;
+}
+.content span.attr, .content a.attr, .content span.derive,
+.content a.derive, .content span.macro, .content a.macro {
+	color: #a37acc;
+}
+
+.sidebar a { color: #53b1db; }
+.sidebar a.current.type { color: #53b1db; }
+.sidebar a.current.associatedtype { color: #53b1db; }
+
+pre.rust .comment { color: #788797; }
+pre.rust .doccomment { color: #a1ac88; }
+
+nav.main .current {
+	border-top-color: #5c6773;
+	border-bottom-color: #5c6773;
+}
+nav.main .separator {
+	border: 1px solid #5c6773;
+}
+a {
+	color: #39AFD7;
+}
+
+.sidebar h2 a,
+.sidebar h3 a {
+	color: white;
+}
+.search-results a {
+	color: #0096cf;
+}
+body.source .example-wrap pre.rust a {
+	background: #333;
+}
+
+details.rustdoc-toggle > summary.hideme > span,
+details.rustdoc-toggle > summary::before {
+	color: #999;
+}
+
+details.rustdoc-toggle > summary::before {
+	filter: invert(100%);
+}
+
+#crate-search, .search-input {
+	background-color: #141920;
+	border-color: #424c57;
+}
+
+#crate-search {
+	/* Without the `!important`, the border-color is ignored for ``...
+	   It cannot be in the group above because `.search-input` has a different border color on
+	   hover. */
+	border-color: #f0f0f0 !important;
+}
+
+.search-input {
+	border-color: #e0e0e0;
+}
+
+.search-input:focus {
+	border-color: #008dfd;
+}
+
+.stab.empty-impl { background: #FFF5D6; border-color: #FFC600; color: #2f2f2f; }
+.stab.unstable { background: #FFF5D6; border-color: #FFC600; color: #2f2f2f; }
+.stab.deprecated { background: #ffc4c4; border-color: #db7b7b; color: #2f2f2f; }
+.stab.must_implement { background: #F3DFFF; border-color: #b07bdb; color: #2f2f2f; }
+.stab.portability { background: #F3DFFF; border-color: #b07bdb; color: #2f2f2f; }
+.stab.portability > code { background: none; }
+
+.rightside,
+.out-of-band {
+	color: grey;
+}
+
+.line-numbers :target { background-color: transparent; }
+
+/* Code highlighting */
+pre.rust .kw { color: #ab8ac1; }
+pre.rust .kw-2, pre.rust .prelude-ty { color: #769acb; }
+pre.rust .number, pre.rust .string { color: #83a300; }
+pre.rust .self, pre.rust .bool-val, pre.rust .prelude-val,
+pre.rust .attribute, pre.rust .attribute .ident { color: #ee6868; }
+pre.rust .macro, pre.rust .macro-nonterminal { color: #3E999F; }
+pre.rust .lifetime { color: #d97f26; }
+pre.rust .question-mark {
+	color: #ff9011;
+}
+
+.example-wrap > pre.line-number {
+	border-color: #4a4949;
+}
+
+a.test-arrow {
+	color: #dedede;
+	background-color: rgba(78, 139, 202, 0.2);
+}
+
+a.test-arrow:hover{
+	background-color: #4e8bca;
+}
+
+.toggle-label,
+.code-attribute {
+	color: #999;
+}
+
+:target {
+	background-color: #494a3d;
+	border-right: 3px solid #bb7410;
+}
+
+pre.compile_fail {
+	border-left: 2px solid rgba(255,0,0,.8);
+}
+
+pre.compile_fail:hover, .information:hover + pre.compile_fail {
+	border-left: 2px solid #f00;
+}
+
+pre.should_panic {
+	border-left: 2px solid rgba(255,0,0,.8);
+}
+
+pre.should_panic:hover, .information:hover + pre.should_panic {
+	border-left: 2px solid #f00;
+}
+
+pre.ignore {
+	border-left: 2px solid rgba(255,142,0,.6);
+}
+
+pre.ignore:hover, .information:hover + pre.ignore {
+	border-left: 2px solid #ff9200;
+}
+
+.tooltip.compile_fail {
+	color: rgba(255,0,0,.8);
+}
+
+.information > .compile_fail:hover {
+	color: #f00;
+}
+
+.tooltip.should_panic {
+	color: rgba(255,0,0,.8);
+}
+
+.information > .should_panic:hover {
+	color: #f00;
+}
+
+.tooltip.ignore {
+	color: rgba(255,142,0,.6);
+}
+
+.information > .ignore:hover {
+	color: #ff9200;
+}
+
+.search-failed a {
+	color: #0089ff;
+}
+
+.tooltip::after {
+	background-color: #000;
+	color: #fff;
+	border-color: #000;
+}
+
+.tooltip::before {
+	border-color: transparent black transparent transparent;
+}
+
+.notable-traits-tooltiptext {
+	background-color: #111;
+	border-color: #777;
+}
+
+.notable-traits-tooltiptext .notable {
+	border-bottom-color: #d2d2d2;
+}
+
+#titles > button:not(.selected) {
+	background-color: #252525;
+	border-top-color: #252525;
+}
+
+#titles > button:hover, #titles > button.selected {
+	border-top-color: #0089ff;
+	background-color: #353535;
+}
+
+#titles > button > div.count {
+	color: #888;
+}
+
+@media (max-width: 700px) {
+	.sidebar-elems {
+		border-right-color: #000;
+	}
+}
+
+kbd {
+	color: #000;
+	background-color: #fafbfc;
+	border-color: #d1d5da;
+	border-bottom-color: #c6cbd1;
+	box-shadow: inset 0 -1px 0 #c6cbd1;
+}
+
+#settings-menu > a, #help-button > button {
+	border-color: #e0e0e0;
+	background: #f0f0f0;
+	color: #000;
+}
+
+#settings-menu > a:hover, #settings-menu > a:focus,
+#help-button > button:hover, #help-button > button:focus {
+	border-color: #ffb900;
+}
+
+.popover, .popover::before,
+#help-button span.top, #help-button span.bottom {
+	border-color: #d2d2d2;
+}
+
+#copy-path {
+	color: #999;
+}
+#copy-path > img {
+	filter: invert(50%);
+}
+#copy-path:hover > img {
+	filter: invert(65%);
+}
+
+#theme-choices {
+	border-color: #e0e0e0;
+	background-color: #353535;
+}
+
+#theme-choices > button:not(:first-child) {
+	border-top-color: #e0e0e0;
+}
+
+#theme-choices > button:hover, #theme-choices > button:focus {
+	background-color: #4e4e4e;
+}
+
+.search-results .result-name span.alias {
+	color: #fff;
+}
+.search-results .result-name span.grey {
+	color: #ccc;
+}
+
+#source-sidebar > .title {
+	border-bottom-color: #ccc;
+}
+#source-sidebar div.files > a:hover, details.dir-entry summary:hover,
+#source-sidebar div.files > a:focus, details.dir-entry summary:focus {
+	background-color: #444;
+}
+#source-sidebar div.files > a.selected {
+	background-color: #333;
+}
+
+.scraped-example-list .scrape-help {
+	border-color: #aaa;
+	color: #eee;
+}
+.scraped-example-list .scrape-help:hover {
+	border-color: white;
+	color: white;
+}
+.more-examples-toggle summary, .more-examples-toggle .hide-more {
+	color: #999;
+}
+.scraped-example .example-wrap .rust span.highlight {
+	background: rgb(91, 59, 1);
+}
+.scraped-example .example-wrap .rust span.highlight.focus {
+	background: rgb(124, 75, 15);
+}
+.scraped-example:not(.expanded) .code-wrapper:before {
+	background: linear-gradient(to bottom, rgba(53, 53, 53, 1), rgba(53, 53, 53, 0));
+}
+.scraped-example:not(.expanded) .code-wrapper:after {
+	background: linear-gradient(to top, rgba(53, 53, 53, 1), rgba(53, 53, 53, 0));
+}
+.toggle-line-inner {
+	background: #999;
+}
+.toggle-line:hover .toggle-line-inner {
+	background: #c5c5c5;
+}
diff --git a/src/librustdoc/html/static/css/themes/light.css b/src/librustdoc/html/static/css/themes/light.css
new file mode 100644
index 000000000..b751acff1
--- /dev/null
+++ b/src/librustdoc/html/static/css/themes/light.css
@@ -0,0 +1,395 @@
+:root {
+	--main-background-color: white;
+	--main-color: black;
+	--settings-input-color: #2196f3;
+	--sidebar-background-color: #F5F5F5;
+	--sidebar-background-color-hover: #E0E0E0;
+	--code-block-background-color: #F5F5F5;
+	--scrollbar-track-background-color: #dcdcdc;
+	--scrollbar-thumb-background-color: rgba(36, 37, 39, 0.6);
+	--scrollbar-color: rgba(36, 37, 39, 0.6) #d9d9d9;
+	--headings-border-bottom-color: #ddd;
+}
+
+.slider {
+	background-color: #ccc;
+}
+.slider:before {
+	background-color: white;
+}
+input:focus + .slider {
+	box-shadow: 0 0 0 2px #0a84ff, 0 0 0 6px rgba(10, 132, 255, 0.3);
+}
+
+.in-band {
+	background-color: white;
+}
+
+.rust-logo {
+	/* This rule exists to force other themes to explicitly style the logo.
+	 * Rustdoc has a custom linter for this purpose.
+	 */
+}
+
+.sidebar .current,
+.sidebar a:hover {
+	background-color: #fff;
+}
+
+.line-numbers span { color: #c67e2d; }
+.line-numbers .line-highlighted {
+	background-color: #FDFFD3 !important;
+}
+
+.docblock table td, .docblock table th {
+	border-color: #ddd;
+}
+
+.search-results a:hover {
+	background-color: #ddd;
+}
+
+.search-results a:focus {
+	color: #000 !important;
+	background-color: #ccc;
+}
+.search-results a:focus span { color: #000 !important; }
+a.result-trait:focus { background-color: #c7b6ff; }
+a.result-traitalias:focus { background-color: #c7b6ff; }
+a.result-mod:focus,
+a.result-externcrate:focus { background-color: #afc6e4; }
+a.result-enum:focus { background-color: #e7b1a0; }
+a.result-struct:focus { background-color: #e7b1a0; }
+a.result-union:focus { background-color: #e7b1a0; }
+a.result-fn:focus,
+a.result-method:focus,
+a.result-tymethod:focus { background-color: #c6afb3; }
+a.result-type:focus { background-color: #e7b1a0; }
+a.result-associatedtype:focus { background-color: #afc6e4; }
+a.result-foreigntype:focus { background-color: #e7b1a0; }
+a.result-attr:focus,
+a.result-derive:focus,
+a.result-macro:focus { background-color: #8ce488; }
+a.result-constant:focus,
+a.result-static:focus { background-color: #afc6e4; }
+a.result-primitive:focus { background-color: #e7b1a0; }
+a.result-keyword:focus { background-color: #afc6e4; }
+
+.content .item-info::before { color: #ccc; }
+
+.content span.enum, .content a.enum, .block a.current.enum { color: #AD378A; }
+.content span.struct, .content a.struct, .block a.current.struct { color: #AD378A; }
+.content span.type, .content a.type, .block a.current.type { color:  #AD378A; }
+.content span.foreigntype, .content a.foreigntype, .block a.current.foreigntype { color: #3873AD; }
+.content span.associatedtype,
+.content a.associatedtype,
+.block a.current.associatedtype { color: #3873AD; }
+.content span.attr, .content a.attr, .block a.current.attr,
+.content span.derive, .content a.derive, .block a.current.derive,
+.content span.macro, .content a.macro, .block a.current.macro { color: #068000; }
+.content span.union, .content a.union, .block a.current.union { color: #AD378A; }
+.content span.constant, .content a.constant, .block a.current.constant,
+.content span.static, .content a.static, .block a.current.static { color: #3873AD; }
+.content span.primitive, .content a.primitive, .block a.current.primitive { color: #AD378A; }
+.content span.externcrate,
+.content span.mod, .content a.mod, .block a.current.mod { color: #3873AD; }
+.content span.trait, .content a.trait, .block a.current.trait { color: #6E4FC9; }
+.content span.traitalias, .content a.traitalias, .block a.current.traitalias { color: #5137AD; }
+.content span.fn, .content a.fn, .block a.current.fn,
+.content span.method, .content a.method, .block a.current.method,
+.content span.tymethod, .content a.tymethod, .block a.current.tymethod,
+.content .fnname { color: #AD7C37; }
+.content span.keyword, .content a.keyword, .block a.current.keyword { color: #3873AD; }
+
+.sidebar a { color: #356da4; }
+.sidebar a.current.enum { color: #a63283; }
+.sidebar a.current.struct { color: #a63283; }
+.sidebar a.current.type { color: #a63283; }
+.sidebar a.current.associatedtype { color: #356da4; }
+.sidebar a.current.foreigntype { color: #356da4; }
+.sidebar a.current.attr,
+.sidebar a.current.derive,
+.sidebar a.current.macro { color: #067901; }
+.sidebar a.current.union { color: #a63283; }
+.sidebar a.current.constant
+.sidebar a.current.static { color: #356da4; }
+.sidebar a.current.primitive { color: #a63283; }
+.sidebar a.current.externcrate
+.sidebar a.current.mod { color: #356da4; }
+.sidebar a.current.trait { color: #6849c3; }
+.sidebar a.current.traitalias { color: #4b349e; }
+.sidebar a.current.fn,
+.sidebar a.current.method,
+.sidebar a.current.tymethod { color: #a67736; }
+.sidebar a.current.keyword { color: #356da4; }
+
+nav.main .current {
+	border-top-color: #000;
+	border-bottom-color: #000;
+}
+nav.main .separator {
+	border: 1px solid #000;
+}
+
+a {
+	color: #3873AD;
+}
+
+body.source .example-wrap pre.rust a {
+	background: #eee;
+}
+
+details.rustdoc-toggle > summary.hideme > span,
+details.rustdoc-toggle > summary::before {
+	color: #999;
+}
+
+#crate-search, .search-input {
+	background-color: white;
+	border-color: #e0e0e0;
+}
+
+#crate-search {
+	/* Without the `!important`, the border-color is ignored for `";
+            for (const c of crates_list) {
+                crates += ``;
+            }
+            crates += "";
+        }
+
+        let typeFilter = "";
+        if (results.query.typeFilter !== NO_TYPE_FILTER) {
+            typeFilter = " (type: " + escape(itemTypes[results.query.typeFilter]) + ")";
+        }
+
+        let output = "
    " +
+            `
    Results for ${escape(results.query.userQuery)}` +
+            `${typeFilter}
    ${crates}
    `;
+        if (results.query.error !== null) {
+            output += `
    Query parser error: "${results.query.error}".
    `;
+            output += "
    " +
+                makeTabHeader(0, "In Names", ret_others[1]) +
+                "
    ";
+            currentTab = 0;
+        } else if (results.query.foundElems <= 1 && results.query.returned.length === 0) {
+            output += "
    " +
+                makeTabHeader(0, "In Names", ret_others[1]) +
+                makeTabHeader(1, "In Parameters", ret_in_args[1]) +
+                makeTabHeader(2, "In Return Types", ret_returned[1]) +
+                "
    ";
+        } else {
+            const signatureTabTitle =
+                results.query.elems.length === 0 ? "In Function Return Types" :
+                results.query.returned.length === 0 ? "In Function Parameters" :
+                "In Function Signatures";
+            output += "
    " +
+                makeTabHeader(0, signatureTabTitle, ret_others[1]) +
+                "
    ";
+            currentTab = 0;
+        }
+
+        const resultsElem = document.createElement("div");
+        resultsElem.id = "results";
+        resultsElem.appendChild(ret_others[0]);
+        resultsElem.appendChild(ret_in_args[0]);
+        resultsElem.appendChild(ret_returned[0]);
+
+        search.innerHTML = output;
+        const crateSearch = document.getElementById("crate-search");
+        if (crateSearch) {
+            crateSearch.addEventListener("input", updateCrate);
+        }
+        search.appendChild(resultsElem);
+        // Reset focused elements.
+        searchState.showResults(search);
+        const elems = document.getElementById("titles").childNodes;
+        searchState.focusedByTab = [];
+        let i = 0;
+        for (const elem of elems) {
+            const j = i;
+            elem.onclick = () => printTab(j);
+            searchState.focusedByTab.push(null);
+            i += 1;
+        }
+        printTab(currentTab);
+    }
+
+    /**
+     * Perform a search based on the current state of the search input element
+     * and display the results.
+     * @param {Event}   [e]       - The event that triggered this search, if any
+     * @param {boolean} [forced]
+     */
+    function search(e, forced) {
+        const params = searchState.getQueryStringParams();
+        const query = parseQuery(searchState.input.value.trim());
+
+        if (e) {
+            e.preventDefault();
+        }
+
+        if (!forced && query.userQuery === currentResults) {
+            if (query.userQuery.length > 0) {
+                putBackSearch();
+            }
+            return;
+        }
+
+        let filterCrates = getFilterCrates();
+
+        // In case we have no information about the saved crate and there is a URL query parameter,
+        // we override it with the URL query parameter.
+        if (filterCrates === null && params["filter-crate"] !== undefined) {
+            filterCrates = params["filter-crate"];
+        }
+
+        // Update document title to maintain a meaningful browser history
+        searchState.title = "Results for " + query.original + " - Rust";
+
+        // Because searching is incremental by character, only the most
+        // recent search query is added to the browser history.
+        if (browserSupportsHistoryApi()) {
+            const newURL = buildUrl(query.original, filterCrates);
+
+            if (!history.state && !params.search) {
+                history.pushState(null, "", newURL);
+            } else {
+                history.replaceState(null, "", newURL);
+            }
+        }
+
+        showResults(
+            execQuery(query, searchWords, filterCrates, window.currentCrate),
+            params.go_to_first,
+            filterCrates);
+    }
+
+    /**
+     * Convert a list of RawFunctionType / ID to object-based FunctionType.
+     *
+     * Crates often have lots of functions in them, and it's common to have a large number of
+     * functions that operate on a small set of data types, so the search index compresses them
+     * by encoding function parameter and return types as indexes into an array of names.
+     *
+     * Even when a general-purpose compression algorithm is used, this is still a win. I checked.
+     * https://github.com/rust-lang/rust/pull/98475#issue-1284395985
+     *
+     * The format for individual function types is encoded in
+     * librustdoc/html/render/mod.rs: impl Serialize for RenderType
+     *
+     * @param {null|Array} types
+     * @param {Array<{name: string, ty: number}>} lowercasePaths
+     *
+     * @return {Array}
+     */
+    function buildItemSearchTypeAll(types, lowercasePaths) {
+        const PATH_INDEX_DATA = 0;
+        const GENERICS_DATA = 1;
+        return types.map(type => {
+            let pathIndex, generics;
+            if (typeof type === "number") {
+                pathIndex = type;
+                generics = [];
+            } else {
+                pathIndex = type[PATH_INDEX_DATA];
+                generics = buildItemSearchTypeAll(type[GENERICS_DATA], lowercasePaths);
+            }
+            return {
+                // `0` is used as a sentinel because it's fewer bytes than `null`
+                name: pathIndex === 0 ? null : lowercasePaths[pathIndex - 1].name,
+                ty: pathIndex === 0 ? null : lowercasePaths[pathIndex - 1].ty,
+                generics: generics,
+            };
+        });
+    }
+
+    /**
+     * Convert from RawFunctionSearchType to FunctionSearchType.
+     *
+     * Crates often have lots of functions in them, and function signatures are sometimes complex,
+     * so rustdoc uses a pretty tight encoding for them. This function converts it to a simpler,
+     * object-based encoding so that the actual search code is more readable and easier to debug.
+     *
+     * The raw function search type format is generated using serde in
+     * librustdoc/html/render/mod.rs: impl Serialize for IndexItemFunctionType
+     *
+     * @param {RawFunctionSearchType} functionSearchType
+     * @param {Array<{name: string, ty: number}>} lowercasePaths
+     *
+     * @return {null|FunctionSearchType}
+     */
+    function buildFunctionSearchType(functionSearchType, lowercasePaths) {
+        const INPUTS_DATA = 0;
+        const OUTPUT_DATA = 1;
+        // `0` is used as a sentinel because it's fewer bytes than `null`
+        if (functionSearchType === 0) {
+            return null;
+        }
+        let inputs, output;
+        if (typeof functionSearchType[INPUTS_DATA] === "number") {
+            const pathIndex = functionSearchType[INPUTS_DATA];
+            inputs = [{
+                name: pathIndex === 0 ? null : lowercasePaths[pathIndex - 1].name,
+                ty: pathIndex === 0 ? null : lowercasePaths[pathIndex - 1].ty,
+                generics: [],
+            }];
+        } else {
+            inputs = buildItemSearchTypeAll(functionSearchType[INPUTS_DATA], lowercasePaths);
+        }
+        if (functionSearchType.length > 1) {
+            if (typeof functionSearchType[OUTPUT_DATA] === "number") {
+                const pathIndex = functionSearchType[OUTPUT_DATA];
+                output = [{
+                    name: pathIndex === 0 ? null : lowercasePaths[pathIndex - 1].name,
+                    ty: pathIndex === 0 ? null : lowercasePaths[pathIndex - 1].ty,
+                    generics: [],
+                }];
+            } else {
+                output = buildItemSearchTypeAll(functionSearchType[OUTPUT_DATA], lowercasePaths);
+            }
+        } else {
+            output = [];
+        }
+        return {
+            inputs, output,
+        };
+    }
+
+    function buildIndex(rawSearchIndex) {
+        searchIndex = [];
+        /**
+         * @type {Array}
+         */
+        const searchWords = [];
+        let i, word;
+        let currentIndex = 0;
+        let id = 0;
+
+        for (const crate in rawSearchIndex) {
+            if (!hasOwnPropertyRustdoc(rawSearchIndex, crate)) {
+                continue;
+            }
+
+            let crateSize = 0;
+
+            /**
+             * The raw search data for a given crate. `n`, `t`, `d`, and `q`, `i`, and `f`
+             * are arrays with the same length. n[i] contains the name of an item.
+             * t[i] contains the type of that item (as a small integer that represents an
+             * offset in `itemTypes`). d[i] contains the description of that item.
+             *
+             * q[i] contains the full path of the item, or an empty string indicating
+             * "same as q[i-1]".
+             *
+             * i[i] contains an item's parent, usually a module. For compactness,
+             * it is a set of indexes into the `p` array.
+             *
+             * f[i] contains function signatures, or `0` if the item isn't a function.
+             * Functions are themselves encoded as arrays. The first item is a list of
+             * types representing the function's inputs, and the second list item is a list
+             * of types representing the function's output. Tuples are flattened.
+             * Types are also represented as arrays; the first item is an index into the `p`
+             * array, while the second is a list of types representing any generic parameters.
+             *
+             * `a` defines aliases with an Array of pairs: [name, offset], where `offset`
+             * points into the n/t/d/q/i/f arrays.
+             *
+             * `doc` contains the description of the crate.
+             *
+             * `p` is a list of path/type pairs. It is used for parents and function parameters.
+             *
+             * @type {{
+             *   doc: string,
+             *   a: Object,
+             *   n: Array,
+             *   t: Array,
+             *   d: Array,
+             *   q: Array,
+             *   i: Array,
+             *   f: Array,
+             *   p: Array,
+             * }}
+             */
+            const crateCorpus = rawSearchIndex[crate];
+
+            searchWords.push(crate);
+            // This object should have exactly the same set of fields as the "row"
+            // object defined below. Your JavaScript runtime will thank you.
+            // https://mathiasbynens.be/notes/shapes-ics
+            const crateRow = {
+                crate: crate,
+                ty: 1, // == ExternCrate
+                name: crate,
+                path: "",
+                desc: crateCorpus.doc,
+                parent: undefined,
+                type: null,
+                id: id,
+                normalizedName: crate.indexOf("_") === -1 ? crate : crate.replace(/_/g, ""),
+            };
+            id += 1;
+            searchIndex.push(crateRow);
+            currentIndex += 1;
+
+            // an array of (Number) item types
+            const itemTypes = crateCorpus.t;
+            // an array of (String) item names
+            const itemNames = crateCorpus.n;
+            // an array of (String) full paths (or empty string for previous path)
+            const itemPaths = crateCorpus.q;
+            // an array of (String) descriptions
+            const itemDescs = crateCorpus.d;
+            // an array of (Number) the parent path index + 1 to `paths`, or 0 if none
+            const itemParentIdxs = crateCorpus.i;
+            // an array of (Object | null) the type of the function, if any
+            const itemFunctionSearchTypes = crateCorpus.f;
+            // an array of [(Number) item type,
+            //              (String) name]
+            const paths = crateCorpus.p;
+            // an array of [(String) alias name
+            //             [Number] index to items]
+            const aliases = crateCorpus.a;
+
+            // an array of [{name: String, ty: Number}]
+            const lowercasePaths = [];
+
+            // convert `rawPaths` entries into object form
+            // generate normalizedPaths for function search mode
+            let len = paths.length;
+            for (i = 0; i < len; ++i) {
+                lowercasePaths.push({ty: paths[i][0], name: paths[i][1].toLowerCase()});
+                paths[i] = {ty: paths[i][0], name: paths[i][1]};
+            }
+
+            // convert `item*` into an object form, and construct word indices.
+            //
+            // before any analysis is performed lets gather the search terms to
+            // search against apart from the rest of the data.  This is a quick
+            // operation that is cached for the life of the page state so that
+            // all other search operations have access to this cached data for
+            // faster analysis operations
+            len = itemTypes.length;
+            let lastPath = "";
+            for (i = 0; i < len; ++i) {
+                // This object should have exactly the same set of fields as the "crateRow"
+                // object defined above.
+                if (typeof itemNames[i] === "string") {
+                    word = itemNames[i].toLowerCase();
+                    searchWords.push(word);
+                } else {
+                    word = "";
+                    searchWords.push("");
+                }
+                const row = {
+                    crate: crate,
+                    ty: itemTypes[i],
+                    name: itemNames[i],
+                    path: itemPaths[i] ? itemPaths[i] : lastPath,
+                    desc: itemDescs[i],
+                    parent: itemParentIdxs[i] > 0 ? paths[itemParentIdxs[i] - 1] : undefined,
+                    type: buildFunctionSearchType(itemFunctionSearchTypes[i], lowercasePaths),
+                    id: id,
+                    normalizedName: word.indexOf("_") === -1 ? word : word.replace(/_/g, ""),
+                };
+                id += 1;
+                searchIndex.push(row);
+                lastPath = row.path;
+                crateSize += 1;
+            }
+
+            if (aliases) {
+                ALIASES[crate] = Object.create(null);
+                for (const alias_name in aliases) {
+                    if (!hasOwnPropertyRustdoc(aliases, alias_name)) {
+                        continue;
+                    }
+
+                    if (!hasOwnPropertyRustdoc(ALIASES[crate], alias_name)) {
+                        ALIASES[crate][alias_name] = [];
+                    }
+                    for (const local_alias of aliases[alias_name]) {
+                        ALIASES[crate][alias_name].push(local_alias + currentIndex);
+                    }
+                }
+            }
+            currentIndex += crateSize;
+        }
+        return searchWords;
+    }
+
+    /**
+     * Callback for when the search form is submitted.
+     * @param {Event} [e] - The event that triggered this call, if any
+     */
+    function onSearchSubmit(e) {
+        e.preventDefault();
+        searchState.clearInputTimeout();
+        search();
+    }
+
+    function putBackSearch() {
+        const search_input = searchState.input;
+        if (!searchState.input) {
+            return;
+        }
+        if (search_input.value !== "" && !searchState.isDisplayed()) {
+            searchState.showResults();
+            if (browserSupportsHistoryApi()) {
+                history.replaceState(null, "",
+                    buildUrl(search_input.value, getFilterCrates()));
+            }
+            document.title = searchState.title;
+        }
+    }
+
+    function registerSearchEvents() {
+        const params = searchState.getQueryStringParams();
+
+        // Populate search bar with query string search term when provided,
+        // but only if the input bar is empty. This avoid the obnoxious issue
+        // where you start trying to do a search, and the index loads, and
+        // suddenly your search is gone!
+        if (searchState.input.value === "") {
+            searchState.input.value = params.search || "";
+        }
+
+        const searchAfter500ms = () => {
+            searchState.clearInputTimeout();
+            if (searchState.input.value.length === 0) {
+                if (browserSupportsHistoryApi()) {
+                    history.replaceState(null, window.currentCrate + " - Rust",
+                        getNakedUrl() + window.location.hash);
+                }
+                searchState.hideResults();
+            } else {
+                searchState.timeout = setTimeout(search, 500);
+            }
+        };
+        searchState.input.onkeyup = searchAfter500ms;
+        searchState.input.oninput = searchAfter500ms;
+        document.getElementsByClassName("search-form")[0].onsubmit = onSearchSubmit;
+        searchState.input.onchange = e => {
+            if (e.target !== document.activeElement) {
+                // To prevent doing anything when it's from a blur event.
+                return;
+            }
+            // Do NOT e.preventDefault() here. It will prevent pasting.
+            searchState.clearInputTimeout();
+            // zero-timeout necessary here because at the time of event handler execution the
+            // pasted content is not in the input field yet. Shouldn’t make any difference for
+            // change, though.
+            setTimeout(search, 0);
+        };
+        searchState.input.onpaste = searchState.input.onchange;
+
+        searchState.outputElement().addEventListener("keydown", e => {
+            // We only handle unmodified keystrokes here. We don't want to interfere with,
+            // for instance, alt-left and alt-right for history navigation.
+            if (e.altKey || e.ctrlKey || e.shiftKey || e.metaKey) {
+                return;
+            }
+            // up and down arrow select next/previous search result, or the
+            // search box if we're already at the top.
+            if (e.which === 38) { // up
+                const previous = document.activeElement.previousElementSibling;
+                if (previous) {
+                    previous.focus();
+                } else {
+                    searchState.focus();
+                }
+                e.preventDefault();
+            } else if (e.which === 40) { // down
+                const next = document.activeElement.nextElementSibling;
+                if (next) {
+                    next.focus();
+                }
+                const rect = document.activeElement.getBoundingClientRect();
+                if (window.innerHeight - rect.bottom < rect.height) {
+                    window.scrollBy(0, rect.height);
+                }
+                e.preventDefault();
+            } else if (e.which === 37) { // left
+                nextTab(-1);
+                e.preventDefault();
+            } else if (e.which === 39) { // right
+                nextTab(1);
+                e.preventDefault();
+            }
+        });
+
+        searchState.input.addEventListener("keydown", e => {
+            if (e.which === 40) { // down
+                focusSearchResult();
+                e.preventDefault();
+            }
+        });
+
+        searchState.input.addEventListener("focus", () => {
+            putBackSearch();
+        });
+
+        searchState.input.addEventListener("blur", () => {
+            searchState.input.placeholder = searchState.input.origPlaceholder;
+        });
+
+        // Push and pop states are used to add search results to the browser
+        // history.
+        if (browserSupportsHistoryApi()) {
+            // Store the previous  so we can revert back to it later.
+            const previousTitle = document.title;
+
+            window.addEventListener("popstate", e => {
+                const params = searchState.getQueryStringParams();
+                // Revert to the previous title manually since the History
+                // API ignores the title parameter.
+                document.title = previousTitle;
+                // When browsing forward to search results the previous
+                // search will be repeated, so the currentResults are
+                // cleared to ensure the search is successful.
+                currentResults = null;
+                // Synchronize search bar with query string state and
+                // perform the search. This will empty the bar if there's
+                // nothing there, which lets you really go back to a
+                // previous state with nothing in the bar.
+                if (params.search && params.search.length > 0) {
+                    searchState.input.value = params.search;
+                    // Some browsers fire "onpopstate" for every page load
+                    // (Chrome), while others fire the event only when actually
+                    // popping a state (Firefox), which is why search() is
+                    // called both here and at the end of the startSearch()
+                    // function.
+                    search(e);
+                } else {
+                    searchState.input.value = "";
+                    // When browsing back from search results the main page
+                    // visibility must be reset.
+                    searchState.hideResults();
+                }
+            });
+        }
+
+        // This is required in firefox to avoid this problem: Navigating to a search result
+        // with the keyboard, hitting enter, and then hitting back would take you back to
+        // the doc page, rather than the search that should overlay it.
+        // This was an interaction between the back-forward cache and our handlers
+        // that try to sync state between the URL and the search input. To work around it,
+        // do a small amount of re-init on page show.
+        window.onpageshow = () => {
+            const qSearch = searchState.getQueryStringParams().search;
+            if (searchState.input.value === "" && qSearch) {
+                searchState.input.value = qSearch;
+            }
+            search();
+        };
+    }
+
+    function updateCrate(ev) {
+        if (ev.target.value === "All crates") {
+            // If we don't remove it from the URL, it'll be picked up again by the search.
+            const params = searchState.getQueryStringParams();
+            const query = searchState.input.value.trim();
+            if (!history.state && !params.search) {
+                history.pushState(null, "", buildUrl(query, null));
+            } else {
+                history.replaceState(null, "", buildUrl(query, null));
+            }
+        }
+        // In case you "cut" the entry from the search input, then change the crate filter
+        // before paste back the previous search, you get the old search results without
+        // the filter. To prevent this, we need to remove the previous results.
+        currentResults = null;
+        search(undefined, true);
+    }
+
+    /**
+     *  @type {Array<string>}
+     */
+    const searchWords = buildIndex(rawSearchIndex);
+    if (typeof window !== "undefined") {
+        registerSearchEvents();
+        // If there's a search term in the URL, execute the search now.
+        if (window.searchState.getQueryStringParams().search) {
+            search();
+        }
+    }
+
+    if (typeof exports !== "undefined") {
+        exports.initSearch = initSearch;
+        exports.execQuery = execQuery;
+        exports.parseQuery = parseQuery;
+    }
+    return searchWords;
+}
+
+if (typeof window !== "undefined") {
+    window.initSearch = initSearch;
+    if (window.searchIndex !== undefined) {
+        initSearch(window.searchIndex);
+    }
+} else {
+    // Running in Node, not a browser. Run initSearch just to produce the
+    // exports.
+    initSearch({});
+}
+
+
+})();
diff --git a/src/librustdoc/html/static/js/settings.js b/src/librustdoc/html/static/js/settings.js
new file mode 100644
index 000000000..797b931af
--- /dev/null
+++ b/src/librustdoc/html/static/js/settings.js
@@ -0,0 +1,272 @@
+// Local js definitions:
+/* global getSettingValue, getVirtualKey, updateLocalStorage, updateSystemTheme */
+/* global addClass, removeClass, onEach, onEachLazy, blurHandler, elemIsInParent */
+/* global MAIN_ID, getVar, getSettingsButton */
+
+"use strict";
+
+(function() {
+    const isSettingsPage = window.location.pathname.endsWith("/settings.html");
+
+    function changeSetting(settingName, value) {
+        updateLocalStorage(settingName, value);
+
+        switch (settingName) {
+            case "theme":
+            case "preferred-dark-theme":
+            case "preferred-light-theme":
+            case "use-system-theme":
+                updateSystemTheme();
+                updateLightAndDark();
+                break;
+        }
+    }
+
+    function handleKey(ev) {
+        // Don't interfere with browser shortcuts
+        if (ev.ctrlKey || ev.altKey || ev.metaKey) {
+            return;
+        }
+        switch (getVirtualKey(ev)) {
+            case "Enter":
+            case "Return":
+            case "Space":
+                ev.target.checked = !ev.target.checked;
+                ev.preventDefault();
+                break;
+        }
+    }
+
+    function showLightAndDark() {
+        addClass(document.getElementById("theme").parentElement, "hidden");
+        removeClass(document.getElementById("preferred-light-theme").parentElement, "hidden");
+        removeClass(document.getElementById("preferred-dark-theme").parentElement, "hidden");
+    }
+
+    function hideLightAndDark() {
+        addClass(document.getElementById("preferred-light-theme").parentElement, "hidden");
+        addClass(document.getElementById("preferred-dark-theme").parentElement, "hidden");
+        removeClass(document.getElementById("theme").parentElement, "hidden");
+    }
+
+    function updateLightAndDark() {
+        if (getSettingValue("use-system-theme") !== "false") {
+            showLightAndDark();
+        } else {
+            hideLightAndDark();
+        }
+    }
+
+    function setEvents(settingsElement) {
+        updateLightAndDark();
+        onEachLazy(settingsElement.getElementsByClassName("slider"), elem => {
+            const toggle = elem.previousElementSibling;
+            const settingId = toggle.id;
+            const settingValue = getSettingValue(settingId);
+            if (settingValue !== null) {
+                toggle.checked = settingValue === "true";
+            }
+            toggle.onchange = function() {
+                changeSetting(this.id, this.checked);
+            };
+            toggle.onkeyup = handleKey;
+            toggle.onkeyrelease = handleKey;
+        });
+        onEachLazy(settingsElement.getElementsByClassName("select-wrapper"), elem => {
+            const select = elem.getElementsByTagName("select")[0];
+            const settingId = select.id;
+            const settingValue = getSettingValue(settingId);
+            if (settingValue !== null) {
+                select.value = settingValue;
+            }
+            select.onchange = function() {
+                changeSetting(this.id, this.value);
+            };
+        });
+        onEachLazy(settingsElement.querySelectorAll("input[type=\"radio\"]"), elem => {
+            const settingId = elem.name;
+            const settingValue = getSettingValue(settingId);
+            if (settingValue !== null && settingValue !== "null") {
+                elem.checked = settingValue === elem.value;
+            }
+            elem.addEventListener("change", ev => {
+                changeSetting(ev.target.name, ev.target.value);
+            });
+        });
+    }
+
+    /**
+     * This function builds the sections inside the "settings page". It takes a `settings` list
+     * as argument which describes each setting and how to render it. It returns a string
+     * representing the raw HTML.
+     *
+     * @param {Array<Object>} settings
+     *
+     * @return {string}
+     */
+    function buildSettingsPageSections(settings) {
+        let output = "";
+
+        for (const setting of settings) {
+            output += "<div class=\"setting-line\">";
+            const js_data_name = setting["js_name"];
+            const setting_name = setting["name"];
+
+            if (setting["options"] !== undefined) {
+                // This is a select setting.
+                output += `<div class="radio-line" id="${js_data_name}">\
+                        <span class="setting-name">${setting_name}</span>\
+                        <div class="choices">`;
+                onEach(setting["options"], option => {
+                    const checked = option === setting["default"] ? " checked" : "";
+
+                    output += `<label for="${js_data_name}-${option}" class="choice">\
+                           <input type="radio" name="${js_data_name}" \
+                                id="${js_data_name}-${option}" value="${option}"${checked}>\
+                           <span>${option}</span>\
+                         </label>`;
+                });
+                output += "</div></div>";
+            } else {
+                // This is a toggle.
+                const checked = setting["default"] === true ? " checked" : "";
+                output += `<label class="toggle">\
+                        <input type="checkbox" id="${js_data_name}"${checked}>\
+                        <span class="slider"></span>\
+                        <span class="label">${setting_name}</span>\
+                    </label>`;
+            }
+            output += "</div>";
+        }
+        return output;
+    }
+
+    /**
+     * This function builds the "settings page" and returns the generated HTML element.
+     *
+     * @return {HTMLElement}
+     */
+    function buildSettingsPage() {
+        const themes = getVar("themes").split(",");
+        const settings = [
+            {
+                "name": "Use system theme",
+                "js_name": "use-system-theme",
+                "default": true,
+            },
+            {
+                "name": "Theme",
+                "js_name": "theme",
+                "default": "light",
+                "options": themes,
+            },
+            {
+                "name": "Preferred light theme",
+                "js_name": "preferred-light-theme",
+                "default": "light",
+                "options": themes,
+            },
+            {
+                "name": "Preferred dark theme",
+                "js_name": "preferred-dark-theme",
+                "default": "dark",
+                "options": themes,
+            },
+            {
+                "name": "Auto-hide item contents for large items",
+                "js_name": "auto-hide-large-items",
+                "default": true,
+            },
+            {
+                "name": "Auto-hide item methods' documentation",
+                "js_name": "auto-hide-method-docs",
+                "default": false,
+            },
+            {
+                "name": "Auto-hide trait implementation documentation",
+                "js_name": "auto-hide-trait-implementations",
+                "default": false,
+            },
+            {
+                "name": "Directly go to item in search if there is only one result",
+                "js_name": "go-to-only-result",
+                "default": false,
+            },
+            {
+                "name": "Show line numbers on code examples",
+                "js_name": "line-numbers",
+                "default": false,
+            },
+            {
+                "name": "Disable keyboard shortcuts",
+                "js_name": "disable-shortcuts",
+                "default": false,
+            },
+        ];
+
+        // Then we build the DOM.
+        const elementKind = isSettingsPage ? "section" : "div";
+        const innerHTML = `<div class="settings">${buildSettingsPageSections(settings)}</div>`;
+        const el = document.createElement(elementKind);
+        el.id = "settings";
+        el.className = "popover";
+        el.innerHTML = innerHTML;
+
+        if (isSettingsPage) {
+            document.getElementById(MAIN_ID).appendChild(el);
+        } else {
+            el.setAttribute("tabindex", "-1");
+            getSettingsButton().appendChild(el);
+        }
+        return el;
+    }
+
+    const settingsMenu = buildSettingsPage();
+
+    function displaySettings() {
+        settingsMenu.style.display = "";
+    }
+
+    function settingsBlurHandler(event) {
+        blurHandler(event, getSettingsButton(), window.hidePopoverMenus);
+    }
+
+    if (isSettingsPage) {
+        // We replace the existing "onclick" callback to do nothing if clicked.
+        getSettingsButton().onclick = function(event) {
+            event.preventDefault();
+        };
+    } else {
+        // We replace the existing "onclick" callback.
+        const settingsButton = getSettingsButton();
+        const settingsMenu = document.getElementById("settings");
+        settingsButton.onclick = function(event) {
+            if (elemIsInParent(event.target, settingsMenu)) {
+                return;
+            }
+            event.preventDefault();
+            const shouldDisplaySettings = settingsMenu.style.display === "none";
+
+            window.hidePopoverMenus();
+            if (shouldDisplaySettings) {
+                displaySettings();
+            }
+        };
+        settingsButton.onblur = settingsBlurHandler;
+        settingsButton.querySelector("a").onblur = settingsBlurHandler;
+        onEachLazy(settingsMenu.querySelectorAll("input"), el => {
+            el.onblur = settingsBlurHandler;
+        });
+        settingsMenu.onblur = settingsBlurHandler;
+    }
+
+    // We now wait a bit for the web browser to end re-computing the DOM...
+    setTimeout(() => {
+        setEvents(settingsMenu);
+        // The setting menu is already displayed if we're on the settings page.
+        if (!isSettingsPage) {
+            displaySettings();
+        }
+        removeClass(getSettingsButton(), "rotate");
+    }, 0);
+})();
diff --git a/src/librustdoc/html/static/js/source-script.js b/src/librustdoc/html/static/js/source-script.js
new file mode 100644
index 000000000..c45d61429
--- /dev/null
+++ b/src/librustdoc/html/static/js/source-script.js
@@ -0,0 +1,241 @@
+// From rust:
+/* global sourcesIndex */
+
+// Local js definitions:
+/* global addClass, getCurrentValue, onEachLazy, removeClass, browserSupportsHistoryApi */
+/* global updateLocalStorage */
+
+"use strict";
+
+(function() {
+
+const rootPath = document.getElementById("rustdoc-vars").attributes["data-root-path"].value;
+let oldScrollPosition = 0;
+
+const NAME_OFFSET = 0;
+const DIRS_OFFSET = 1;
+const FILES_OFFSET = 2;
+
+function closeSidebarIfMobile() {
+    if (window.innerWidth < window.RUSTDOC_MOBILE_BREAKPOINT) {
+        updateLocalStorage("source-sidebar-show", "false");
+    }
+}
+
+function createDirEntry(elem, parent, fullPath, hasFoundFile) {
+    const dirEntry = document.createElement("details");
+    const summary = document.createElement("summary");
+
+    dirEntry.className = "dir-entry";
+
+    fullPath += elem[NAME_OFFSET] + "/";
+
+    summary.innerText = elem[NAME_OFFSET];
+    dirEntry.appendChild(summary);
+
+    const folders = document.createElement("div");
+    folders.className = "folders";
+    if (elem[DIRS_OFFSET]) {
+        for (const dir of elem[DIRS_OFFSET]) {
+            if (createDirEntry(dir, folders, fullPath, false)) {
+                dirEntry.open = true;
+                hasFoundFile = true;
+            }
+        }
+    }
+    dirEntry.appendChild(folders);
+
+    const files = document.createElement("div");
+    files.className = "files";
+    if (elem[FILES_OFFSET]) {
+        for (const file_text of elem[FILES_OFFSET]) {
+            const file = document.createElement("a");
+            file.innerText = file_text;
+            file.href = rootPath + "src/" + fullPath + file_text + ".html";
+            file.addEventListener("click", closeSidebarIfMobile);
+            const w = window.location.href.split("#")[0];
+            if (!hasFoundFile && w === file.href) {
+                file.className = "selected";
+                dirEntry.open = true;
+                hasFoundFile = true;
+            }
+            files.appendChild(file);
+        }
+    }
+    dirEntry.appendChild(files);
+    parent.appendChild(dirEntry);
+    return hasFoundFile;
+}
+
+function toggleSidebar() {
+    const child = this.parentNode.children[0];
+    if (child.innerText === ">") {
+        if (window.innerWidth < window.RUSTDOC_MOBILE_BREAKPOINT) {
+            // This is to keep the scroll position on mobile.
+            oldScrollPosition = window.scrollY;
+            document.body.style.position = "fixed";
+            document.body.style.top = `-${oldScrollPosition}px`;
+        }
+        addClass(document.documentElement, "source-sidebar-expanded");
+        child.innerText = "<";
+        updateLocalStorage("source-sidebar-show", "true");
+    } else {
+        if (window.innerWidth < window.RUSTDOC_MOBILE_BREAKPOINT) {
+            // This is to keep the scroll position on mobile.
+            document.body.style.position = "";
+            document.body.style.top = "";
+            // The scroll position is lost when resetting the style, hence why we store it in
+            // `oldScroll`.
+            window.scrollTo(0, oldScrollPosition);
+        }
+        removeClass(document.documentElement, "source-sidebar-expanded");
+        child.innerText = ">";
+        updateLocalStorage("source-sidebar-show", "false");
+    }
+}
+
+function createSidebarToggle() {
+    const sidebarToggle = document.createElement("div");
+    sidebarToggle.id = "sidebar-toggle";
+
+    const inner = document.createElement("button");
+
+    if (getCurrentValue("source-sidebar-show") === "true") {
+        inner.innerText = "<";
+    } else {
+        inner.innerText = ">";
+    }
+    inner.onclick = toggleSidebar;
+
+    sidebarToggle.appendChild(inner);
+    return sidebarToggle;
+}
+
+// This function is called from "source-files.js", generated in `html/render/mod.rs`.
+// eslint-disable-next-line no-unused-vars
+function createSourceSidebar() {
+    const container = document.querySelector("nav.sidebar");
+
+    const sidebarToggle = createSidebarToggle();
+    container.insertBefore(sidebarToggle, container.firstChild);
+
+    const sidebar = document.createElement("div");
+    sidebar.id = "source-sidebar";
+
+    let hasFoundFile = false;
+
+    const title = document.createElement("div");
+    title.className = "title";
+    title.innerText = "Files";
+    sidebar.appendChild(title);
+    Object.keys(sourcesIndex).forEach(key => {
+        sourcesIndex[key][NAME_OFFSET] = key;
+        hasFoundFile = createDirEntry(sourcesIndex[key], sidebar, "",
+            hasFoundFile);
+    });
+
+    container.appendChild(sidebar);
+    // Focus on the current file in the source files sidebar.
+    const selected_elem = sidebar.getElementsByClassName("selected")[0];
+    if (typeof selected_elem !== "undefined") {
+        selected_elem.focus();
+    }
+}
+
+const lineNumbersRegex = /^#?(\d+)(?:-(\d+))?$/;
+
+function highlightSourceLines(match) {
+    if (typeof match === "undefined") {
+        match = window.location.hash.match(lineNumbersRegex);
+    }
+    if (!match) {
+        return;
+    }
+    let from = parseInt(match[1], 10);
+    let to = from;
+    if (typeof match[2] !== "undefined") {
+        to = parseInt(match[2], 10);
+    }
+    if (to < from) {
+        const tmp = to;
+        to = from;
+        from = tmp;
+    }
+    let elem = document.getElementById(from);
+    if (!elem) {
+        return;
+    }
+    const x = document.getElementById(from);
+    if (x) {
+        x.scrollIntoView();
+    }
+    onEachLazy(document.getElementsByClassName("line-numbers"), e => {
+        onEachLazy(e.getElementsByTagName("span"), i_e => {
+            removeClass(i_e, "line-highlighted");
+        });
+    });
+    for (let i = from; i <= to; ++i) {
+        elem = document.getElementById(i);
+        if (!elem) {
+            break;
+        }
+        addClass(elem, "line-highlighted");
+    }
+}
+
+const handleSourceHighlight = (function() {
+    let prev_line_id = 0;
+
+    const set_fragment = name => {
+        const x = window.scrollX,
+            y = window.scrollY;
+        if (browserSupportsHistoryApi()) {
+            history.replaceState(null, null, "#" + name);
+            highlightSourceLines();
+        } else {
+            location.replace("#" + name);
+        }
+        // Prevent jumps when selecting one or many lines
+        window.scrollTo(x, y);
+    };
+
+    return ev => {
+        let cur_line_id = parseInt(ev.target.id, 10);
+        // It can happen when clicking not on a line number span.
+        if (isNaN(cur_line_id)) {
+            return;
+        }
+        ev.preventDefault();
+
+        if (ev.shiftKey && prev_line_id) {
+            // Swap selection if needed
+            if (prev_line_id > cur_line_id) {
+                const tmp = prev_line_id;
+                prev_line_id = cur_line_id;
+                cur_line_id = tmp;
+            }
+
+            set_fragment(prev_line_id + "-" + cur_line_id);
+        } else {
+            prev_line_id = cur_line_id;
+
+            set_fragment(cur_line_id);
+        }
+    };
+}());
+
+window.addEventListener("hashchange", () => {
+    const match = window.location.hash.match(lineNumbersRegex);
+    if (match) {
+        return highlightSourceLines(match);
+    }
+});
+
+onEachLazy(document.getElementsByClassName("line-numbers"), el => {
+    el.addEventListener("click", handleSourceHighlight);
+});
+
+highlightSourceLines();
+
+window.createSourceSidebar = createSourceSidebar;
+})();
diff --git a/src/librustdoc/html/static/js/storage.js b/src/librustdoc/html/static/js/storage.js
new file mode 100644
index 000000000..0c5389d45
--- /dev/null
+++ b/src/librustdoc/html/static/js/storage.js
@@ -0,0 +1,268 @@
+// storage.js is loaded in the `<head>` of all rustdoc pages and doesn't
+// use `async` or `defer`. That means it blocks further parsing and rendering
+// of the page: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script.
+// This makes it the correct place to act on settings that affect the display of
+// the page, so we don't see major layout changes during the load of the page.
+"use strict";
+
+const darkThemes = ["dark", "ayu"];
+window.currentTheme = document.getElementById("themeStyle");
+window.mainTheme = document.getElementById("mainThemeStyle");
+
+// WARNING: RUSTDOC_MOBILE_BREAKPOINT MEDIA QUERY
+// If you update this line, then you also need to update the two media queries with the same
+// warning in rustdoc.css
+window.RUSTDOC_MOBILE_BREAKPOINT = 701;
+
+const settingsDataset = (function() {
+    const settingsElement = document.getElementById("default-settings");
+    if (settingsElement === null) {
+        return null;
+    }
+    const dataset = settingsElement.dataset;
+    if (dataset === undefined) {
+        return null;
+    }
+    return dataset;
+})();
+
+function getSettingValue(settingName) {
+    const current = getCurrentValue(settingName);
+    if (current !== null) {
+        return current;
+    }
+    if (settingsDataset !== null) {
+        // See the comment for `default_settings.into_iter()` etc. in
+        // `Options::from_matches` in `librustdoc/config.rs`.
+        const def = settingsDataset[settingName.replace(/-/g,"_")];
+        if (def !== undefined) {
+            return def;
+        }
+    }
+    return null;
+}
+
+const localStoredTheme = getSettingValue("theme");
+
+const savedHref = [];
+
+// eslint-disable-next-line no-unused-vars
+function hasClass(elem, className) {
+    return elem && elem.classList && elem.classList.contains(className);
+}
+
+// eslint-disable-next-line no-unused-vars
+function addClass(elem, className) {
+    if (!elem || !elem.classList) {
+        return;
+    }
+    elem.classList.add(className);
+}
+
+// eslint-disable-next-line no-unused-vars
+function removeClass(elem, className) {
+    if (!elem || !elem.classList) {
+        return;
+    }
+    elem.classList.remove(className);
+}
+
+/**
+ * Run a callback for every element of an Array.
+ * @param {Array<?>}    arr        - The array to iterate over
+ * @param {function(?)} func       - The callback
+ * @param {boolean}     [reversed] - Whether to iterate in reverse
+ */
+function onEach(arr, func, reversed) {
+    if (arr && arr.length > 0 && func) {
+        if (reversed) {
+            const length = arr.length;
+            for (let i = length - 1; i >= 0; --i) {
+                if (func(arr[i])) {
+                    return true;
+                }
+            }
+        } else {
+            for (const elem of arr) {
+                if (func(elem)) {
+                    return true;
+                }
+            }
+        }
+    }
+    return false;
+}
+
+/**
+ * Turn an HTMLCollection or a NodeList into an Array, then run a callback
+ * for every element. This is useful because iterating over an HTMLCollection
+ * or a "live" NodeList while modifying it can be very slow.
+ * https://developer.mozilla.org/en-US/docs/Web/API/HTMLCollection
+ * https://developer.mozilla.org/en-US/docs/Web/API/NodeList
+ * @param {NodeList<?>|HTMLCollection<?>} lazyArray  - An array to iterate over
+ * @param {function(?)}                   func       - The callback
+ * @param {boolean}                       [reversed] - Whether to iterate in reverse
+ */
+function onEachLazy(lazyArray, func, reversed) {
+    return onEach(
+        Array.prototype.slice.call(lazyArray),
+        func,
+        reversed);
+}
+
+function updateLocalStorage(name, value) {
+    try {
+        window.localStorage.setItem("rustdoc-" + name, value);
+    } catch (e) {
+        // localStorage is not accessible, do nothing
+    }
+}
+
+function getCurrentValue(name) {
+    try {
+        return window.localStorage.getItem("rustdoc-" + name);
+    } catch (e) {
+        return null;
+    }
+}
+
+function switchTheme(styleElem, mainStyleElem, newTheme, saveTheme) {
+    const newHref = mainStyleElem.href.replace(
+        /\/rustdoc([^/]*)\.css/, "/" + newTheme + "$1" + ".css");
+
+    // If this new value comes from a system setting or from the previously
+    // saved theme, no need to save it.
+    if (saveTheme) {
+        updateLocalStorage("theme", newTheme);
+    }
+
+    if (styleElem.href === newHref) {
+        return;
+    }
+
+    let found = false;
+    if (savedHref.length === 0) {
+        onEachLazy(document.getElementsByTagName("link"), el => {
+            savedHref.push(el.href);
+        });
+    }
+    onEach(savedHref, el => {
+        if (el === newHref) {
+            found = true;
+            return true;
+        }
+    });
+    if (found) {
+        styleElem.href = newHref;
+    }
+}
+
+// This function is called from "main.js".
+// eslint-disable-next-line no-unused-vars
+function useSystemTheme(value) {
+    if (value === undefined) {
+        value = true;
+    }
+
+    updateLocalStorage("use-system-theme", value);
+
+    // update the toggle if we're on the settings page
+    const toggle = document.getElementById("use-system-theme");
+    if (toggle && toggle instanceof HTMLInputElement) {
+        toggle.checked = value;
+    }
+}
+
+const updateSystemTheme = (function() {
+    if (!window.matchMedia) {
+        // fallback to the CSS computed value
+        return () => {
+            const cssTheme = getComputedStyle(document.documentElement)
+                .getPropertyValue("content");
+
+            switchTheme(
+                window.currentTheme,
+                window.mainTheme,
+                JSON.parse(cssTheme) || "light",
+                true
+            );
+        };
+    }
+
+    // only listen to (prefers-color-scheme: dark) because light is the default
+    const mql = window.matchMedia("(prefers-color-scheme: dark)");
+
+    function handlePreferenceChange(mql) {
+        const use = theme => {
+            switchTheme(window.currentTheme, window.mainTheme, theme, true);
+        };
+        // maybe the user has disabled the setting in the meantime!
+        if (getSettingValue("use-system-theme") !== "false") {
+            const lightTheme = getSettingValue("preferred-light-theme") || "light";
+            const darkTheme = getSettingValue("preferred-dark-theme") || "dark";
+
+            if (mql.matches) {
+                use(darkTheme);
+            } else {
+                // prefers a light theme, or has no preference
+                use(lightTheme);
+            }
+            // note: we save the theme so that it doesn't suddenly change when
+            // the user disables "use-system-theme" and reloads the page or
+            // navigates to another page
+        } else {
+            use(getSettingValue("theme"));
+        }
+    }
+
+    mql.addListener(handlePreferenceChange);
+
+    return () => {
+        handlePreferenceChange(mql);
+    };
+})();
+
+function switchToSavedTheme() {
+    switchTheme(
+        window.currentTheme,
+        window.mainTheme,
+        getSettingValue("theme") || "light",
+        false
+    );
+}
+
+if (getSettingValue("use-system-theme") !== "false" && window.matchMedia) {
+    // update the preferred dark theme if the user is already using a dark theme
+    // See https://github.com/rust-lang/rust/pull/77809#issuecomment-707875732
+    if (getSettingValue("use-system-theme") === null
+        && getSettingValue("preferred-dark-theme") === null
+        && darkThemes.indexOf(localStoredTheme) >= 0) {
+        updateLocalStorage("preferred-dark-theme", localStoredTheme);
+    }
+
+    // call the function to initialize the theme at least once!
+    updateSystemTheme();
+} else {
+    switchToSavedTheme();
+}
+
+if (getSettingValue("source-sidebar-show") === "true") {
+    // At this point in page load, `document.body` is not available yet.
+    // Set a class on the `<html>` element instead.
+    addClass(document.documentElement, "source-sidebar-expanded");
+}
+
+// If we navigate away (for example to a settings page), and then use the back or
+// forward button to get back to a page, the theme may have changed in the meantime.
+// But scripts may not be re-loaded in such a case due to the bfcache
+// (https://web.dev/bfcache/). The "pageshow" event triggers on such navigations.
+// Use that opportunity to update the theme.
+// We use a setTimeout with a 0 timeout here to put the change on the event queue.
+// For some reason, if we try to change the theme while the `pageshow` event is
+// running, it sometimes fails to take effect. The problem manifests on Chrome,
+// specifically when talking to a remote website with no caching.
+window.addEventListener("pageshow", ev => {
+    if (ev.persisted) {
+        setTimeout(switchToSavedTheme, 0);
+    }
+});
diff --git a/src/librustdoc/html/static/scrape-examples-help.md b/src/librustdoc/html/static/scrape-examples-help.md
new file mode 100644
index 000000000..035b2e18b
--- /dev/null
+++ b/src/librustdoc/html/static/scrape-examples-help.md
@@ -0,0 +1,34 @@
+Rustdoc will automatically scrape examples of documented items from the `examples/` directory of a project. These examples will be included within the generated documentation for that item. For example, if your library contains a public function:
+
+```rust
+// src/lib.rs
+pub fn a_func() {}
+```
+
+And you have an example calling this function:
+
+```rust
+// examples/ex.rs
+fn main() {
+  a_crate::a_func();
+}
+```
+
+Then this code snippet will be included in the documentation for `a_func`.
+
+## How to read scraped examples
+
+Scraped examples are shown as blocks of code from a given file. The relevant item will be highlighted. If the file is larger than a couple lines, only a small window will be shown which you can expand by clicking ↕ in the top-right. If a file contains multiple instances of an item, you can use the ≺ and ≻ buttons to toggle through each instance.
+
+If there is more than one file that contains examples, then you should click "More examples" to see these examples.
+
+
+## How Rustdoc scrapes examples
+
+When you run `cargo doc`, Rustdoc will analyze all the crates that match Cargo's `--examples` filter for instances of items that occur in the crates being documented. Then Rustdoc will include the source code of these instances in the generated documentation.
+
+Rustdoc has a few techniques to ensure this doesn't overwhelm documentation readers, and that it doesn't blow up the page size:
+
+1. For a given item, a maximum of 5 examples are included in the page. The remaining examples are just links to source code.
+2. Only one example is shown by default, and the remaining examples are hidden behind a toggle.
+3. For a given file that contains examples, only the item containing the examples will be included in the generated documentation.
diff --git a/src/librustdoc/html/static_files.rs b/src/librustdoc/html/static_files.rs
new file mode 100644
index 000000000..75f2b7e35
--- /dev/null
+++ b/src/librustdoc/html/static_files.rs
@@ -0,0 +1,168 @@
+//! Static files bundled with documentation output.
+//!
+//! All the static files are included here for centralized access in case anything other than the
+//! HTML rendering code (say, the theme checker) needs to access one of these files.
+//!
+//! Note about types: CSS and JavaScript files are included as `&'static str` to allow for the
+//! minifier to run on them. All other files are included as `&'static [u8]` so they can be
+//! directly written to a `Write` handle.
+
+/// The file contents of the main `rustdoc.css` file, responsible for the core layout of the page.
+pub(crate) static RUSTDOC_CSS: &str = include_str!("static/css/rustdoc.css");
+
+/// The file contents of `settings.css`, responsible for the items on the settings page.
+pub(crate) static SETTINGS_CSS: &str = include_str!("static/css/settings.css");
+
+/// The file contents of the `noscript.css` file, used in case JS isn't supported or is disabled.
+pub(crate) static NOSCRIPT_CSS: &str = include_str!("static/css/noscript.css");
+
+/// The file contents of `normalize.css`, included to even out standard elements between browser
+/// implementations.
+pub(crate) static NORMALIZE_CSS: &str = include_str!("static/css/normalize.css");
+
+/// The file contents of `main.js`, which contains the core JavaScript used on documentation pages,
+/// including search behavior and docblock folding, among others.
+pub(crate) static MAIN_JS: &str = include_str!("static/js/main.js");
+
+/// The file contents of `search.js`, which contains the search behavior.
+pub(crate) static SEARCH_JS: &str = include_str!("static/js/search.js");
+
+/// The file contents of `settings.js`, which contains the JavaScript used to handle the settings
+/// page.
+pub(crate) static SETTINGS_JS: &str = include_str!("static/js/settings.js");
+
+/// The file contents of `storage.js`, which contains functionality related to browser Local
+/// Storage, used to store documentation settings.
+pub(crate) static STORAGE_JS: &str = include_str!("static/js/storage.js");
+
+/// The file contents of `scraped-examples.js`, which contains functionality related to the
+/// --scrape-examples flag that inserts automatically-found examples of usages of items.
+pub(crate) static SCRAPE_EXAMPLES_JS: &str = include_str!("static/js/scrape-examples.js");
+
+pub(crate) static SCRAPE_EXAMPLES_HELP_MD: &str = include_str!("static/scrape-examples-help.md");
+
+/// The file contents of `wheel.svg`, the icon used for the settings button.
+pub(crate) static WHEEL_SVG: &[u8] = include_bytes!("static/images/wheel.svg");
+
+/// The file contents of `clipboard.svg`, the icon used for the "copy path" button.
+pub(crate) static CLIPBOARD_SVG: &[u8] = include_bytes!("static/images/clipboard.svg");
+
+/// The file contents of `down-arrow.svg`, the icon used for the crate choice combobox.
+pub(crate) static DOWN_ARROW_SVG: &[u8] = include_bytes!("static/images/down-arrow.svg");
+
+/// The file contents of `toggle-minus.svg`, the icon used for opened toggles.
+pub(crate) static TOGGLE_MINUS_PNG: &[u8] = include_bytes!("static/images/toggle-minus.svg");
+
+/// The file contents of `toggle-plus.svg`, the icon used for closed toggles.
+pub(crate) static TOGGLE_PLUS_PNG: &[u8] = include_bytes!("static/images/toggle-plus.svg");
+
+/// The contents of `COPYRIGHT.txt`, the license listing for files distributed with documentation
+/// output.
+pub(crate) static COPYRIGHT: &[u8] = include_bytes!("static/COPYRIGHT.txt");
+
+/// The contents of `LICENSE-APACHE.txt`, the text of the Apache License, version 2.0.
+pub(crate) static LICENSE_APACHE: &[u8] = include_bytes!("static/LICENSE-APACHE.txt");
+
+/// The contents of `LICENSE-MIT.txt`, the text of the MIT License.
+pub(crate) static LICENSE_MIT: &[u8] = include_bytes!("static/LICENSE-MIT.txt");
+
+/// The contents of `rust-logo.svg`, the default icon of the documentation.
+pub(crate) static RUST_LOGO_SVG: &[u8] = include_bytes!("static/images/rust-logo.svg");
+
+/// The default documentation favicons (SVG and PNG fallbacks)
+pub(crate) static RUST_FAVICON_SVG: &[u8] = include_bytes!("static/images/favicon.svg");
+pub(crate) static RUST_FAVICON_PNG_16: &[u8] = include_bytes!("static/images/favicon-16x16.png");
+pub(crate) static RUST_FAVICON_PNG_32: &[u8] = include_bytes!("static/images/favicon-32x32.png");
+
+/// The built-in themes given to every documentation site.
+pub(crate) mod themes {
+    /// The "light" theme, selected by default when no setting is available. Used as the basis for
+    /// the `--check-theme` functionality.
+    pub(crate) static LIGHT: &str = include_str!("static/css/themes/light.css");
+
+    /// The "dark" theme.
+    pub(crate) static DARK: &str = include_str!("static/css/themes/dark.css");
+
+    /// The "ayu" theme.
+    pub(crate) static AYU: &str = include_str!("static/css/themes/ayu.css");
+}
+
+/// Files related to the Fira Sans font.
+pub(crate) mod fira_sans {
+    /// The file `FiraSans-Regular.woff2`, the Regular variant of the Fira Sans font in woff2.
+    pub(crate) static REGULAR: &[u8] = include_bytes!("static/fonts/FiraSans-Regular.woff2");
+
+    /// The file `FiraSans-Medium.woff2`, the Medium variant of the Fira Sans font in woff2.
+    pub(crate) static MEDIUM: &[u8] = include_bytes!("static/fonts/FiraSans-Medium.woff2");
+
+    /// The file `FiraSans-LICENSE.txt`, the license text for the Fira Sans font.
+    pub(crate) static LICENSE: &[u8] = include_bytes!("static/fonts/FiraSans-LICENSE.txt");
+}
+
+/// Files related to the Source Serif 4 font.
+pub(crate) mod source_serif_4 {
+    /// The file `SourceSerif4-Regular.ttf.woff2`, the Regular variant of the Source Serif 4 font in
+    /// woff2.
+    pub(crate) static REGULAR: &[u8] =
+        include_bytes!("static/fonts/SourceSerif4-Regular.ttf.woff2");
+
+    /// The file `SourceSerif4-Bold.ttf.woff2`, the Bold variant of the Source Serif 4 font in
+    /// woff2.
+    pub(crate) static BOLD: &[u8] = include_bytes!("static/fonts/SourceSerif4-Bold.ttf.woff2");
+
+    /// The file `SourceSerif4-It.ttf.woff2`, the Italic variant of the Source Serif 4 font in
+    /// woff2.
+    pub(crate) static ITALIC: &[u8] = include_bytes!("static/fonts/SourceSerif4-It.ttf.woff2");
+
+    /// The file `SourceSerif4-LICENSE.txt`, the license text for the Source Serif 4 font.
+    pub(crate) static LICENSE: &[u8] = include_bytes!("static/fonts/SourceSerif4-LICENSE.md");
+}
+
+/// Files related to the Source Code Pro font.
+pub(crate) mod source_code_pro {
+    /// The file `SourceCodePro-Regular.ttf.woff2`, the Regular variant of the Source Code Pro font
+    /// in woff2.
+    pub(crate) static REGULAR: &[u8] =
+        include_bytes!("static/fonts/SourceCodePro-Regular.ttf.woff2");
+
+    /// The file `SourceCodePro-Semibold.ttf.woff2`, the Semibold variant of the Source Code Pro
+    /// font in woff2.
+    pub(crate) static SEMIBOLD: &[u8] =
+        include_bytes!("static/fonts/SourceCodePro-Semibold.ttf.woff2");
+
+    /// The file `SourceCodePro-It.ttf.woff2`, the Italic variant of the Source Code Pro font in
+    /// woff2.
+    pub(crate) static ITALIC: &[u8] = include_bytes!("static/fonts/SourceCodePro-It.ttf.woff2");
+
+    /// The file `SourceCodePro-LICENSE.txt`, the license text of the Source Code Pro font.
+    pub(crate) static LICENSE: &[u8] = include_bytes!("static/fonts/SourceCodePro-LICENSE.txt");
+}
+
+/// Files related to the Nanum Barun Gothic font.
+///
+/// These files are used to avoid some legacy CJK serif fonts in Windows.
+///
+/// Note that the Noto Sans KR font, which was used previously but was not very readable on Windows,
+/// has been replaced by the Nanum Barun Gothic font. This is due to Windows' implementation of font
+/// rendering that distorts OpenType fonts too much.
+///
+/// The font files were generated with these commands:
+///
+/// ```sh
+/// pyftsubset NanumBarunGothic.ttf \
+/// --unicodes=U+AC00-D7AF,U+1100-11FF,U+3130-318F,U+A960-A97F,U+D7B0-D7FF \
+/// --output-file=NanumBarunGothic.ttf.woff2 --flavor=woff2
+/// ```
+pub(crate) mod nanum_barun_gothic {
+    /// The file `NanumBarunGothic.ttf.woff2`, the Regular variant of the Nanum Barun Gothic font.
+    pub(crate) static REGULAR: &[u8] = include_bytes!("static/fonts/NanumBarunGothic.ttf.woff2");
+
+    /// The file `NanumBarunGothic-LICENSE.txt`, the license text of the Nanum Barun Gothic font.
+    pub(crate) static LICENSE: &[u8] = include_bytes!("static/fonts/NanumBarunGothic-LICENSE.txt");
+}
+
+/// Files related to the sidebar in rustdoc sources.
+pub(crate) mod sidebar {
+    /// File script to handle sidebar.
+    pub(crate) static SOURCE_SCRIPT: &str = include_str!("static/js/source-script.js");
+}
diff --git a/src/librustdoc/html/templates/STYLE.md b/src/librustdoc/html/templates/STYLE.md
new file mode 100644
index 000000000..fff65e3b5
--- /dev/null
+++ b/src/librustdoc/html/templates/STYLE.md
@@ -0,0 +1,37 @@
+# Style for Templates
+
+This directory has templates in the [Tera templating language](teradoc), which is very
+similar to [Jinja2](jinjadoc) and [Django](djangodoc) templates, and also to [Askama](askamadoc).
+
+[teradoc]: https://tera.netlify.app/docs/#templates
+[jinjadoc]: https://jinja.palletsprojects.com/en/3.0.x/templates/
+[djangodoc]: https://docs.djangoproject.com/en/3.2/topics/templates/
+[askamadoc]: https://docs.rs/askama/0.10.5/askama/
+
+We want our rendered output to have as little unnecessary whitespace as
+possible, so that pages load quickly. To achieve that we use Tera's
+[whitespace control] features. At the end of most lines, we put an empty comment
+tag with the whitespace control characters: `{#- -#}`. This causes all
+whitespace between the end of the line and the beginning of the next, including
+indentation, to be omitted on render. Sometimes we want to preserve a single
+space. In those cases we put the space at the end of the line, followed by
+`{# -#}`, which is a directive to remove following whitespace but not preceding.
+We also use the whitespace control characters in most instances of tags with
+control flow, for example `{%- if foo -%}`.
+
+[whitespace control]: https://tera.netlify.app/docs/#whitespace-control
+
+We want our templates to be readable, so we use indentation and newlines
+liberally. We indent by four spaces after opening an HTML tag _or_ a Tera
+tag. In most cases an HTML tag should be followed by a newline, but if the
+tag has simple contents and fits with its close tag on a single line, the
+contents don't necessarily need a new line.
+
+Tera templates support quite sophisticated control flow. To keep our templates
+simple and understandable, we use only a subset: `if` and `for`. In particular
+we avoid [assignments in the template logic](assignments) and [Tera
+macros](macros). This also may make things easier if we switch to a different
+Jinja-style template system, like Askama, in the future.
+
+[assignments]: https://tera.netlify.app/docs/#assignments
+[macros]: https://tera.netlify.app/docs/#macros
diff --git a/src/librustdoc/html/templates/page.html b/src/librustdoc/html/templates/page.html
new file mode 100644
index 000000000..8e25f6764
--- /dev/null
+++ b/src/librustdoc/html/templates/page.html
@@ -0,0 +1,148 @@
+<!DOCTYPE html> {#- -#}
+<html lang="en"> {#- -#}
+<head> {#- -#}
+    <meta charset="utf-8"> {#- -#}
+    <meta name="viewport" content="width=device-width, initial-scale=1.0"> {#- -#}
+    <meta name="generator" content="rustdoc"> {#- -#}
+    <meta name="description" content="{{page.description}}"> {#- -#}
+    <meta name="keywords" content="{{page.keywords}}"> {#- -#}
+    <title>{{page.title}} {#- -#}
+     {#- -#}
+     {#- -#}
+     {#- -#}
+     {#- -#}
+     {#- -#}
+     {#- -#}
+     {#- -#}
+     {#- -#}
+    {%- for theme in themes -%}
+        
+    {%- endfor -%}
+     {#- -#}
+     {#- -#}
+    {%- if page.css_class.contains("crate") -%}
+     {#- -#}
+    {%- else if page.css_class == "source" -%}
+     {#- -#}
+     {#- -#}
+    {%- else if !page.css_class.contains("mod") -%}
+     {#- -#}
+    {%- endif -%}
+     {#- -#}
+    {%- if layout.scrape_examples_extension -%}
+     {#- -#}
+    {%- endif -%}
+     {#- -#}
+    {%- if layout.css_file_extension.is_some() -%}
+         {#- -#}
+    {%- endif -%}
+    {%- if !layout.favicon.is_empty() -%}
+         {#- -#}
+    {%- else -%}
+         {#- -#}
+         {#- -#}
+         {#- -#}
+    {%- endif -%}
+    {{- layout.external_html.in_header|safe -}}
+ {#- -#}
+ {#- -#}
+     {#- -#}
+    {{- layout.external_html.before_content|safe -}}
+     {#- -#}
+     {#- -#}
+    
     {#- -#}
+        
     {#- -#}
+            
     {#- -#}
+                 {#- -#}
+                    {%- if !layout.logo.is_empty()  %}
+                        logo {#- -#}
+                    {%- else -%}
+                         {#- -#}
+                    {%- endif -%}
+                 {#- -#}
+                 {#- -#}
+            
     {#- -#}
+            
    {{- content|safe -}}
     {#- -#}
+        
     {#- -#}
+    
     {#- -#}
+    {{- layout.external_html.after_content|safe -}}
+    
     {#- -#}
+    
     {#- -#}
+ {#- -#}
+ {#- -#}
diff --git a/src/librustdoc/html/templates/print_item.html b/src/librustdoc/html/templates/print_item.html
new file mode 100644
index 000000000..c755157d2
--- /dev/null
+++ b/src/librustdoc/html/templates/print_item.html
@@ -0,0 +1,30 @@
+
     {#- -#}
+    
     {#- -#}
+         {#- -#}
+            {{-typ-}}
+            {#- The breadcrumbs of the item path, like std::string -#}
+            {%- for component in path_components -%}
+            {{component.name}}::
+            {%- endfor -%}
+            {{name}} {#- -#}
+             {#- -#}
+         {#- -#}
+    
     {#- -#}
+     {#- -#}
+        {% if !stability_since_raw.is_empty() %}
+        {{- stability_since_raw|safe }} · {# -#}
+        {% endif %}
+        {%- match src_href -%}
+            {%- when Some with (href) -%}
+                source · {# -#}
+            {%- else -%}
+        {%- endmatch -%}
+         {#- -#}
+            [−] {#- -#}
+         {#- -#}
+     {#- -#}
+
     {#- -#}
diff --git a/src/librustdoc/html/tests.rs b/src/librustdoc/html/tests.rs
new file mode 100644
index 000000000..437d3995e
--- /dev/null
+++ b/src/librustdoc/html/tests.rs
@@ -0,0 +1,50 @@
+use crate::html::format::href_relative_parts;
+use rustc_span::{sym, Symbol};
+
+fn assert_relative_path(expected: &[Symbol], relative_to_fqp: &[Symbol], fqp: &[Symbol]) {
+    // No `create_default_session_globals_then` call is needed here because all
+    // the symbols used are static, and no `Symbol::intern` calls occur.
+    assert_eq!(expected, href_relative_parts(&fqp, &relative_to_fqp).collect::>());
+}
+
+#[test]
+fn href_relative_parts_basic() {
+    let relative_to_fqp = &[sym::std, sym::vec];
+    let fqp = &[sym::std, sym::iter];
+    assert_relative_path(&[sym::dotdot, sym::iter], relative_to_fqp, fqp);
+}
+
+#[test]
+fn href_relative_parts_parent_module() {
+    let relative_to_fqp = &[sym::std, sym::vec];
+    let fqp = &[sym::std];
+    assert_relative_path(&[sym::dotdot], relative_to_fqp, fqp);
+}
+
+#[test]
+fn href_relative_parts_different_crate() {
+    let relative_to_fqp = &[sym::std, sym::vec];
+    let fqp = &[sym::core, sym::iter];
+    assert_relative_path(&[sym::dotdot, sym::dotdot, sym::core, sym::iter], relative_to_fqp, fqp);
+}
+
+#[test]
+fn href_relative_parts_same_module() {
+    let relative_to_fqp = &[sym::std, sym::vec];
+    let fqp = &[sym::std, sym::vec];
+    assert_relative_path(&[], relative_to_fqp, fqp);
+}
+
+#[test]
+fn href_relative_parts_child_module() {
+    let relative_to_fqp = &[sym::std];
+    let fqp = &[sym::std, sym::vec];
+    assert_relative_path(&[sym::vec], relative_to_fqp, fqp);
+}
+
+#[test]
+fn href_relative_parts_root() {
+    let relative_to_fqp = &[];
+    let fqp = &[sym::std];
+    assert_relative_path(&[sym::std], relative_to_fqp, fqp);
+}
diff --git a/src/librustdoc/html/toc.rs b/src/librustdoc/html/toc.rs
new file mode 100644
index 000000000..a12c2a6a1
--- /dev/null
+++ b/src/librustdoc/html/toc.rs
@@ -0,0 +1,191 @@
+//! Table-of-contents creation.
+
+/// A (recursive) table of contents
+#[derive(Debug, PartialEq)]
+pub(crate) struct Toc {
+    /// The levels are strictly decreasing, i.e.
+    ///
+    /// `entries[0].level >= entries[1].level >= ...`
+    ///
+    /// Normally they are equal, but can differ in cases like A and B,
+    /// both of which end up in the same `Toc` as they have the same
+    /// parent (Main).
+    ///
+    /// ```text
+    /// # Main
+    /// ### A
+    /// ## B
+    /// ```
+    entries: Vec,
+}
+
+impl Toc {
+    fn count_entries_with_level(&self, level: u32) -> usize {
+        self.entries.iter().filter(|e| e.level == level).count()
+    }
+}
+
+#[derive(Debug, PartialEq)]
+pub(crate) struct TocEntry {
+    level: u32,
+    sec_number: String,
+    name: String,
+    id: String,
+    children: Toc,
+}
+
+/// Progressive construction of a table of contents.
+#[derive(PartialEq)]
+pub(crate) struct TocBuilder {
+    top_level: Toc,
+    /// The current hierarchy of parent headings, the levels are
+    /// strictly increasing (i.e., `chain[0].level < chain[1].level <
+    /// ...`) with each entry being the most recent occurrence of a
+    /// heading with that level (it doesn't include the most recent
+    /// occurrences of every level, just, if it *is* in `chain` then
+    /// it is the most recent one).
+    ///
+    /// We also have `chain[0].level <= top_level.entries[last]`.
+    chain: Vec,
+}
+
+impl TocBuilder {
+    pub(crate) fn new() -> TocBuilder {
+        TocBuilder { top_level: Toc { entries: Vec::new() }, chain: Vec::new() }
+    }
+
+    /// Converts into a true `Toc` struct.
+    pub(crate) fn into_toc(mut self) -> Toc {
+        // we know all levels are >= 1.
+        self.fold_until(0);
+        self.top_level
+    }
+
+    /// Collapse the chain until the first heading more important than
+    /// `level` (i.e., lower level)
+    ///
+    /// Example:
+    ///
+    /// ```text
+    /// ## A
+    /// # B
+    /// # C
+    /// ## D
+    /// ## E
+    /// ### F
+    /// #### G
+    /// ### H
+    /// ```
+    ///
+    /// If we are considering H (i.e., level 3), then A and B are in
+    /// self.top_level, D is in C.children, and C, E, F, G are in
+    /// self.chain.
+    ///
+    /// When we attempt to push H, we realize that first G is not the
+    /// parent (level is too high) so it is popped from chain and put
+    /// into F.children, then F isn't the parent (level is equal, aka
+    /// sibling), so it's also popped and put into E.children.
+    ///
+    /// This leaves us looking at E, which does have a smaller level,
+    /// and, by construction, it's the most recent thing with smaller
+    /// level, i.e., it's the immediate parent of H.
+    fn fold_until(&mut self, level: u32) {
+        let mut this = None;
+        loop {
+            match self.chain.pop() {
+                Some(mut next) => {
+                    next.children.entries.extend(this);
+                    if next.level < level {
+                        // this is the parent we want, so return it to
+                        // its rightful place.
+                        self.chain.push(next);
+                        return;
+                    } else {
+                        this = Some(next);
+                    }
+                }
+                None => {
+                    self.top_level.entries.extend(this);
+                    return;
+                }
+            }
+        }
+    }
+
+    /// Push a level `level` heading into the appropriate place in the
+    /// hierarchy, returning a string containing the section number in
+    /// `..` format.
+    pub(crate) fn push(&mut self, level: u32, name: String, id: String) -> &str {
+        assert!(level >= 1);
+
+        // collapse all previous sections into their parents until we
+        // get to relevant heading (i.e., the first one with a smaller
+        // level than us)
+        self.fold_until(level);
+
+        let mut sec_number;
+        {
+            let (toc_level, toc) = match self.chain.last() {
+                None => {
+                    sec_number = String::new();
+                    (0, &self.top_level)
+                }
+                Some(entry) => {
+                    sec_number = entry.sec_number.clone();
+                    sec_number.push('.');
+                    (entry.level, &entry.children)
+                }
+            };
+            // fill in any missing zeros, e.g., for
+            // # Foo (1)
+            // ### Bar (1.0.1)
+            for _ in toc_level..level - 1 {
+                sec_number.push_str("0.");
+            }
+            let number = toc.count_entries_with_level(level);
+            sec_number.push_str(&(number + 1).to_string())
+        }
+
+        self.chain.push(TocEntry {
+            level,
+            name,
+            sec_number,
+            id,
+            children: Toc { entries: Vec::new() },
+        });
+
+        // get the thing we just pushed, so we can borrow the string
+        // out of it with the right lifetime
+        let just_inserted = self.chain.last_mut().unwrap();
+        &just_inserted.sec_number
+    }
+}
+
+impl Toc {
+    fn print_inner(&self, v: &mut String) {
+        use std::fmt::Write as _;
+
+        v.push_str("
      ");
+        for entry in &self.entries {
+            // recursively format this table of contents
+            let _ = write!(
+                v,
+                "\n
    • {num} {name}",
+                id = entry.id,
+                num = entry.sec_number,
+                name = entry.name
+            );
+            entry.children.print_inner(&mut *v);
+            v.push_str("
      • ");
+        }
+        v.push_str("
    ");
+    }
+    pub(crate) fn print(&self) -> String {
+        let mut v = String::new();
+        self.print_inner(&mut v);
+        v
+    }
+}
+
+#[cfg(test)]
+mod tests;
diff --git a/src/librustdoc/html/toc/tests.rs b/src/librustdoc/html/toc/tests.rs
new file mode 100644
index 000000000..014f34686
--- /dev/null
+++ b/src/librustdoc/html/toc/tests.rs
@@ -0,0 +1,79 @@
+use super::{Toc, TocBuilder, TocEntry};
+
+#[test]
+fn builder_smoke() {
+    let mut builder = TocBuilder::new();
+
+    // this is purposely not using a fancy macro like below so
+    // that we're sure that this is doing the correct thing, and
+    // there's been no macro mistake.
+    macro_rules! push {
+        ($level: expr, $name: expr) => {
+            assert_eq!(builder.push($level, $name.to_string(), "".to_string()), $name);
+        };
+    }
+    push!(2, "0.1");
+    push!(1, "1");
+    {
+        push!(2, "1.1");
+        {
+            push!(3, "1.1.1");
+            push!(3, "1.1.2");
+        }
+        push!(2, "1.2");
+        {
+            push!(3, "1.2.1");
+            push!(3, "1.2.2");
+        }
+    }
+    push!(1, "2");
+    push!(1, "3");
+    {
+        push!(4, "3.0.0.1");
+        {
+            push!(6, "3.0.0.1.0.1");
+        }
+        push!(4, "3.0.0.2");
+        push!(2, "3.1");
+        {
+            push!(4, "3.1.0.1");
+        }
+    }
+
+    macro_rules! toc {
+        ($(($level: expr, $name: expr, $(($sub: tt))* )),*) => {
+            Toc {
+                entries: vec![
+                    $(
+                        TocEntry {
+                            level: $level,
+                            name: $name.to_string(),
+                            sec_number: $name.to_string(),
+                            id: "".to_string(),
+                            children: toc!($($sub),*)
+                        }
+                        ),*
+                    ]
+            }
+        }
+    }
+    let expected = toc!(
+        (2, "0.1",),
+        (
+            1,
+            "1",
+            ((2, "1.1", ((3, "1.1.1",))((3, "1.1.2",))))((
+                2,
+                "1.2",
+                ((3, "1.2.1",))((3, "1.2.2",))
+            ))
+        ),
+        (1, "2",),
+        (
+            1,
+            "3",
+            ((4, "3.0.0.1", ((6, "3.0.0.1.0.1",))))((4, "3.0.0.2",))((2, "3.1", ((4, "3.1.0.1",))))
+        )
+    );
+    assert_eq!(expected, builder.into_toc());
+}
diff --git a/src/librustdoc/html/url_parts_builder.rs b/src/librustdoc/html/url_parts_builder.rs
new file mode 100644
index 000000000..1e6af6af6
--- /dev/null
+++ b/src/librustdoc/html/url_parts_builder.rs
@@ -0,0 +1,180 @@
+use std::fmt::{self, Write};
+
+use rustc_span::Symbol;
+
+/// A builder that allows efficiently and easily constructing the part of a URL
+/// after the domain: `nightly/core/str/struct.Bytes.html`.
+///
+/// This type is a wrapper around the final `String` buffer,
+/// but its API is like that of a `Vec` of URL components.
+#[derive(Debug)]
+pub(crate) struct UrlPartsBuilder {
+    buf: String,
+}
+
+impl UrlPartsBuilder {
+    /// Create an empty buffer.
+    #[allow(dead_code)]
+    pub(crate) fn new() -> Self {
+        Self { buf: String::new() }
+    }
+
+    /// Create an empty buffer with capacity for the specified number of bytes.
+    fn with_capacity_bytes(count: usize) -> Self {
+        Self { buf: String::with_capacity(count) }
+    }
+
+    /// Create a buffer with one URL component.
+    ///
+    /// # Examples
+    ///
+    /// Basic usage:
+    ///
+    /// ```ignore (private-type)
+    /// let builder = UrlPartsBuilder::singleton("core");
+    /// assert_eq!(builder.finish(), "core");
+    /// ```
+    ///
+    /// Adding more components afterward.
+    ///
+    /// ```ignore (private-type)
+    /// let mut builder = UrlPartsBuilder::singleton("core");
+    /// builder.push("str");
+    /// builder.push_front("nightly");
+    /// assert_eq!(builder.finish(), "nightly/core/str");
+    /// ```
+    pub(crate) fn singleton(part: &str) -> Self {
+        Self { buf: part.to_owned() }
+    }
+
+    /// Push a component onto the buffer.
+    ///
+    /// # Examples
+    ///
+    /// Basic usage:
+    ///
+    /// ```ignore (private-type)
+    /// let mut builder = UrlPartsBuilder::new();
+    /// builder.push("core");
+    /// builder.push("str");
+    /// builder.push("struct.Bytes.html");
+    /// assert_eq!(builder.finish(), "core/str/struct.Bytes.html");
+    /// ```
+    pub(crate) fn push(&mut self, part: &str) {
+        if !self.buf.is_empty() {
+            self.buf.push('/');
+        }
+        self.buf.push_str(part);
+    }
+
+    /// Push a component onto the buffer, using [`format!`]'s formatting syntax.
+    ///
+    /// # Examples
+    ///
+    /// Basic usage (equivalent to the example for [`UrlPartsBuilder::push`]):
+    ///
+    /// ```ignore (private-type)
+    /// let mut builder = UrlPartsBuilder::new();
+    /// builder.push("core");
+    /// builder.push("str");
+    /// builder.push_fmt(format_args!("{}.{}.html", "struct", "Bytes"));
+    /// assert_eq!(builder.finish(), "core/str/struct.Bytes.html");
+    /// ```
+    pub(crate) fn push_fmt(&mut self, args: fmt::Arguments<'_>) {
+        if !self.buf.is_empty() {
+            self.buf.push('/');
+        }
+        self.buf.write_fmt(args).unwrap()
+    }
+
+    /// Push a component onto the front of the buffer.
+    ///
+    /// # Examples
+    ///
+    /// Basic usage:
+    ///
+    /// ```ignore (private-type)
+    /// let mut builder = UrlPartsBuilder::new();
+    /// builder.push("core");
+    /// builder.push("str");
+    /// builder.push_front("nightly");
+    /// builder.push("struct.Bytes.html");
+    /// assert_eq!(builder.finish(), "nightly/core/str/struct.Bytes.html");
+    /// ```
+    pub(crate) fn push_front(&mut self, part: &str) {
+        let is_empty = self.buf.is_empty();
+        self.buf.reserve(part.len() + if !is_empty { 1 } else { 0 });
+        self.buf.insert_str(0, part);
+        if !is_empty {
+            self.buf.insert(part.len(), '/');
+        }
+    }
+
+    /// Get the final `String` buffer.
+    pub(crate) fn finish(self) -> String {
+        self.buf
+    }
+}
+
+/// This is just a guess at the average length of a URL part,
+/// used for [`String::with_capacity`] calls in the [`FromIterator`]
+/// and [`Extend`] impls, and for [estimating item path lengths].
+///
+/// The value `8` was chosen for two main reasons:
+///
+/// * It seems like a good guess for the average part length.
+/// * jemalloc's size classes are all multiples of eight,
+///   which means that the amount of memory it allocates will often match
+///   the amount requested, avoiding wasted bytes.
+///
+/// [estimating item path lengths]: estimate_item_path_byte_length
+const AVG_PART_LENGTH: usize = 8;
+
+/// Estimate the number of bytes in an item's path, based on how many segments it has.
+///
+/// **Note:** This is only to be used with, e.g., [`String::with_capacity()`];
+/// the return value is just a rough estimate.
+pub(crate) const fn estimate_item_path_byte_length(segment_count: usize) -> usize {
+    AVG_PART_LENGTH * segment_count
+}
+
+impl<'a> FromIterator<&'a str> for UrlPartsBuilder {
+    fn from_iter>(iter: T) -> Self {
+        let iter = iter.into_iter();
+        let mut builder = Self::with_capacity_bytes(AVG_PART_LENGTH * iter.size_hint().0);
+        iter.for_each(|part| builder.push(part));
+        builder
+    }
+}
+
+impl<'a> Extend<&'a str> for UrlPartsBuilder {
+    fn extend>(&mut self, iter: T) {
+        let iter = iter.into_iter();
+        self.buf.reserve(AVG_PART_LENGTH * iter.size_hint().0);
+        iter.for_each(|part| self.push(part));
+    }
+}
+
+impl FromIterator for UrlPartsBuilder {
+    fn from_iter>(iter: T) -> Self {
+        // This code has to be duplicated from the `&str` impl because of
+        // `Symbol::as_str`'s lifetimes.
+        let iter = iter.into_iter();
+        let mut builder = Self::with_capacity_bytes(AVG_PART_LENGTH * iter.size_hint().0);
+        iter.for_each(|part| builder.push(part.as_str()));
+        builder
+    }
+}
+
+impl Extend for UrlPartsBuilder {
+    fn extend>(&mut self, iter: T) {
+        // This code has to be duplicated from the `&str` impl because of
+        // `Symbol::as_str`'s lifetimes.
+        let iter = iter.into_iter();
+        self.buf.reserve(AVG_PART_LENGTH * iter.size_hint().0);
+        iter.for_each(|part| self.push(part.as_str()));
+    }
+}
+
+#[cfg(test)]
+mod tests;
diff --git a/src/librustdoc/html/url_parts_builder/tests.rs b/src/librustdoc/html/url_parts_builder/tests.rs
new file mode 100644
index 000000000..636e1ab55
--- /dev/null
+++ b/src/librustdoc/html/url_parts_builder/tests.rs
@@ -0,0 +1,64 @@
+use super::*;
+
+fn t(builder: UrlPartsBuilder, expect: &str) {
+    assert_eq!(builder.finish(), expect);
+}
+
+#[test]
+fn empty() {
+    t(UrlPartsBuilder::new(), "");
+}
+
+#[test]
+fn singleton() {
+    t(UrlPartsBuilder::singleton("index.html"), "index.html");
+}
+
+#[test]
+fn push_several() {
+    let mut builder = UrlPartsBuilder::new();
+    builder.push("core");
+    builder.push("str");
+    builder.push("struct.Bytes.html");
+    t(builder, "core/str/struct.Bytes.html");
+}
+
+#[test]
+fn push_front_empty() {
+    let mut builder = UrlPartsBuilder::new();
+    builder.push_front("page.html");
+    t(builder, "page.html");
+}
+
+#[test]
+fn push_front_non_empty() {
+    let mut builder = UrlPartsBuilder::new();
+    builder.push("core");
+    builder.push("str");
+    builder.push("struct.Bytes.html");
+    builder.push_front("nightly");
+    t(builder, "nightly/core/str/struct.Bytes.html");
+}
+
+#[test]
+fn push_fmt() {
+    let mut builder = UrlPartsBuilder::new();
+    builder.push_fmt(format_args!("{}", "core"));
+    builder.push("str");
+    builder.push_front("nightly");
+    builder.push_fmt(format_args!("{}.{}.html", "struct", "Bytes"));
+    t(builder, "nightly/core/str/struct.Bytes.html");
+}
+
+#[test]
+fn collect() {
+    t(["core", "str"].into_iter().collect(), "core/str");
+    t(["core", "str", "struct.Bytes.html"].into_iter().collect(), "core/str/struct.Bytes.html");
+}
+
+#[test]
+fn extend() {
+    let mut builder = UrlPartsBuilder::singleton("core");
+    builder.extend(["str", "struct.Bytes.html"]);
+    t(builder, "core/str/struct.Bytes.html");
+}
diff --git a/src/librustdoc/json/conversions.rs b/src/librustdoc/json/conversions.rs
new file mode 100644
index 000000000..716a4c9ea
--- /dev/null
+++ b/src/librustdoc/json/conversions.rs
@@ -0,0 +1,798 @@
+//! These from impls are used to create the JSON types which get serialized. They're very close to
+//! the `clean` types but with some fields removed or stringified to simplify the output and not
+//! expose unstable compiler internals.
+
+#![allow(rustc::default_hash_types)]
+
+use std::convert::From;
+use std::fmt;
+
+use rustc_ast::ast;
+use rustc_hir::{def::CtorKind, def_id::DefId};
+use rustc_middle::ty::{self, TyCtxt};
+use rustc_span::{Pos, Symbol};
+use rustc_target::spec::abi::Abi as RustcAbi;
+
+use rustdoc_json_types::*;
+
+use crate::clean::utils::print_const_expr;
+use crate::clean::{self, ItemId};
+use crate::formats::item_type::ItemType;
+use crate::json::JsonRenderer;
+
+impl JsonRenderer<'_> {
+    pub(super) fn convert_item(&self, item: clean::Item) -> Option {
+        let deprecation = item.deprecation(self.tcx);
+        let links = self
+            .cache
+            .intra_doc_links
+            .get(&item.item_id)
+            .into_iter()
+            .flatten()
+            .map(|clean::ItemLink { link, did, .. }| {
+                (link.clone(), from_item_id((*did).into(), self.tcx))
+            })
+            .collect();
+        let docs = item.attrs.collapsed_doc_value();
+        let attrs = item
+            .attrs
+            .other_attrs
+            .iter()
+            .map(rustc_ast_pretty::pprust::attribute_to_string)
+            .collect();
+        let span = item.span(self.tcx);
+        let clean::Item { name, attrs: _, kind: _, visibility, item_id, cfg: _ } = item;
+        let inner = match *item.kind {
+            clean::KeywordItem => return None,
+            clean::StrippedItem(ref inner) => {
+                match &**inner {
+                    // We document non-empty stripped modules as with `Module::is_stripped` set to
+                    // `true`, to prevent contained items from being orphaned for downstream users,
+                    // as JSON does no inlining.
+                    clean::ModuleItem(m) if !m.items.is_empty() => from_clean_item(item, self.tcx),
+                    _ => return None,
+                }
+            }
+            _ => from_clean_item(item, self.tcx),
+        };
+        Some(Item {
+            id: from_item_id_with_name(item_id, self.tcx, name),
+            crate_id: item_id.krate().as_u32(),
+            name: name.map(|sym| sym.to_string()),
+            span: self.convert_span(span),
+            visibility: self.convert_visibility(visibility),
+            docs,
+            attrs,
+            deprecation: deprecation.map(from_deprecation),
+            inner,
+            links,
+        })
+    }
+
+    fn convert_span(&self, span: clean::Span) -> Option {
+        match span.filename(self.sess()) {
+            rustc_span::FileName::Real(name) => {
+                if let Some(local_path) = name.into_local_path() {
+                    let hi = span.hi(self.sess());
+                    let lo = span.lo(self.sess());
+                    Some(Span {
+                        filename: local_path,
+                        begin: (lo.line, lo.col.to_usize()),
+                        end: (hi.line, hi.col.to_usize()),
+                    })
+                } else {
+                    None
+                }
+            }
+            _ => None,
+        }
+    }
+
+    fn convert_visibility(&self, v: clean::Visibility) -> Visibility {
+        use clean::Visibility::*;
+        match v {
+            Public => Visibility::Public,
+            Inherited => Visibility::Default,
+            Restricted(did) if did.is_crate_root() => Visibility::Crate,
+            Restricted(did) => Visibility::Restricted {
+                parent: from_item_id(did.into(), self.tcx),
+                path: self.tcx.def_path(did).to_string_no_crate_verbose(),
+            },
+        }
+    }
+}
+
+pub(crate) trait FromWithTcx {
+    fn from_tcx(f: T, tcx: TyCtxt<'_>) -> Self;
+}
+
+pub(crate) trait IntoWithTcx {
+    fn into_tcx(self, tcx: TyCtxt<'_>) -> T;
+}
+
+impl IntoWithTcx for T
+where
+    U: FromWithTcx,
+{
+    fn into_tcx(self, tcx: TyCtxt<'_>) -> U {
+        U::from_tcx(self, tcx)
+    }
+}
+
+pub(crate) fn from_deprecation(deprecation: rustc_attr::Deprecation) -> Deprecation {
+    #[rustfmt::skip]
+    let rustc_attr::Deprecation { since, note, is_since_rustc_version: _, suggestion: _ } = deprecation;
+    Deprecation { since: since.map(|s| s.to_string()), note: note.map(|s| s.to_string()) }
+}
+
+impl FromWithTcx for GenericArgs {
+    fn from_tcx(args: clean::GenericArgs, tcx: TyCtxt<'_>) -> Self {
+        use clean::GenericArgs::*;
+        match args {
+            AngleBracketed { args, bindings } => GenericArgs::AngleBracketed {
+                args: args.into_vec().into_iter().map(|a| a.into_tcx(tcx)).collect(),
+                bindings: bindings.into_iter().map(|a| a.into_tcx(tcx)).collect(),
+            },
+            Parenthesized { inputs, output } => GenericArgs::Parenthesized {
+                inputs: inputs.into_vec().into_iter().map(|a| a.into_tcx(tcx)).collect(),
+                output: output.map(|a| (*a).into_tcx(tcx)),
+            },
+        }
+    }
+}
+
+impl FromWithTcx for GenericArg {
+    fn from_tcx(arg: clean::GenericArg, tcx: TyCtxt<'_>) -> Self {
+        use clean::GenericArg::*;
+        match arg {
+            Lifetime(l) => GenericArg::Lifetime(l.0.to_string()),
+            Type(t) => GenericArg::Type(t.into_tcx(tcx)),
+            Const(box c) => GenericArg::Const(c.into_tcx(tcx)),
+            Infer => GenericArg::Infer,
+        }
+    }
+}
+
+impl FromWithTcx for Constant {
+    fn from_tcx(constant: clean::Constant, tcx: TyCtxt<'_>) -> Self {
+        let expr = constant.expr(tcx);
+        let value = constant.value(tcx);
+        let is_literal = constant.is_literal(tcx);
+        Constant { type_: constant.type_.into_tcx(tcx), expr, value, is_literal }
+    }
+}
+
+impl FromWithTcx for TypeBinding {
+    fn from_tcx(binding: clean::TypeBinding, tcx: TyCtxt<'_>) -> Self {
+        TypeBinding {
+            name: binding.assoc.name.to_string(),
+            args: binding.assoc.args.into_tcx(tcx),
+            binding: binding.kind.into_tcx(tcx),
+        }
+    }
+}
+
+impl FromWithTcx for TypeBindingKind {
+    fn from_tcx(kind: clean::TypeBindingKind, tcx: TyCtxt<'_>) -> Self {
+        use clean::TypeBindingKind::*;
+        match kind {
+            Equality { term } => TypeBindingKind::Equality(term.into_tcx(tcx)),
+            Constraint { bounds } => {
+                TypeBindingKind::Constraint(bounds.into_iter().map(|a| a.into_tcx(tcx)).collect())
+            }
+        }
+    }
+}
+
+/// It generates an ID as follows:
+///
+/// `CRATE_ID:ITEM_ID[:NAME_ID]` (if there is no name, NAME_ID is not generated).
+pub(crate) fn from_item_id(item_id: ItemId, tcx: TyCtxt<'_>) -> Id {
+    from_item_id_with_name(item_id, tcx, None)
+}
+
+// FIXME: this function (and appending the name at the end of the ID) should be removed when
+// reexports are not inlined anymore for json format. It should be done in #93518.
+pub(crate) fn from_item_id_with_name(item_id: ItemId, tcx: TyCtxt<'_>, name: Option) -> Id {
+    struct DisplayDefId<'a>(DefId, TyCtxt<'a>, Option);
+
+    impl<'a> fmt::Display for DisplayDefId<'a> {
+        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+            let name = match self.2 {
+                Some(name) => format!(":{}", name.as_u32()),
+                None => self
+                    .1
+                    .opt_item_name(self.0)
+                    .map(|n| format!(":{}", n.as_u32()))
+                    .unwrap_or_default(),
+            };
+            write!(f, "{}:{}{}", self.0.krate.as_u32(), u32::from(self.0.index), name)
+        }
+    }
+
+    match item_id {
+        ItemId::DefId(did) => Id(format!("{}", DisplayDefId(did, tcx, name))),
+        ItemId::Blanket { for_, impl_id } => {
+            Id(format!("b:{}-{}", DisplayDefId(impl_id, tcx, None), DisplayDefId(for_, tcx, name)))
+        }
+        ItemId::Auto { for_, trait_ } => {
+            Id(format!("a:{}-{}", DisplayDefId(trait_, tcx, None), DisplayDefId(for_, tcx, name)))
+        }
+        ItemId::Primitive(ty, krate) => Id(format!("p:{}:{}", krate.as_u32(), ty.as_sym())),
+    }
+}
+
+fn from_clean_item(item: clean::Item, tcx: TyCtxt<'_>) -> ItemEnum {
+    use clean::ItemKind::*;
+    let name = item.name;
+    let is_crate = item.is_crate();
+    let header = item.fn_header(tcx);
+
+    match *item.kind {
+        ModuleItem(m) => {
+            ItemEnum::Module(Module { is_crate, items: ids(m.items, tcx), is_stripped: false })
+        }
+        ImportItem(i) => ItemEnum::Import(i.into_tcx(tcx)),
+        StructItem(s) => ItemEnum::Struct(s.into_tcx(tcx)),
+        UnionItem(u) => ItemEnum::Union(u.into_tcx(tcx)),
+        StructFieldItem(f) => ItemEnum::StructField(f.into_tcx(tcx)),
+        EnumItem(e) => ItemEnum::Enum(e.into_tcx(tcx)),
+        VariantItem(v) => ItemEnum::Variant(v.into_tcx(tcx)),
+        FunctionItem(f) => ItemEnum::Function(from_function(f, header.unwrap(), tcx)),
+        ForeignFunctionItem(f) => ItemEnum::Function(from_function(f, header.unwrap(), tcx)),
+        TraitItem(t) => ItemEnum::Trait(t.into_tcx(tcx)),
+        TraitAliasItem(t) => ItemEnum::TraitAlias(t.into_tcx(tcx)),
+        MethodItem(m, _) => ItemEnum::Method(from_function_method(m, true, header.unwrap(), tcx)),
+        TyMethodItem(m) => ItemEnum::Method(from_function_method(m, false, header.unwrap(), tcx)),
+        ImplItem(i) => ItemEnum::Impl(i.into_tcx(tcx)),
+        StaticItem(s) => ItemEnum::Static(s.into_tcx(tcx)),
+        ForeignStaticItem(s) => ItemEnum::Static(s.into_tcx(tcx)),
+        ForeignTypeItem => ItemEnum::ForeignType,
+        TypedefItem(t) => ItemEnum::Typedef(t.into_tcx(tcx)),
+        OpaqueTyItem(t) => ItemEnum::OpaqueTy(t.into_tcx(tcx)),
+        ConstantItem(c) => ItemEnum::Constant(c.into_tcx(tcx)),
+        MacroItem(m) => ItemEnum::Macro(m.source),
+        ProcMacroItem(m) => ItemEnum::ProcMacro(m.into_tcx(tcx)),
+        PrimitiveItem(p) => ItemEnum::PrimitiveType(p.as_sym().to_string()),
+        TyAssocConstItem(ty) => ItemEnum::AssocConst { type_: ty.into_tcx(tcx), default: None },
+        AssocConstItem(ty, default) => {
+            ItemEnum::AssocConst { type_: ty.into_tcx(tcx), default: Some(default.expr(tcx)) }
+        }
+        TyAssocTypeItem(g, b) => ItemEnum::AssocType {
+            generics: (*g).into_tcx(tcx),
+            bounds: b.into_iter().map(|x| x.into_tcx(tcx)).collect(),
+            default: None,
+        },
+        AssocTypeItem(t, b) => ItemEnum::AssocType {
+            generics: t.generics.into_tcx(tcx),
+            bounds: b.into_iter().map(|x| x.into_tcx(tcx)).collect(),
+            default: Some(t.item_type.unwrap_or(t.type_).into_tcx(tcx)),
+        },
+        // `convert_item` early returns `None` for stripped items and keywords.
+        KeywordItem => unreachable!(),
+        StrippedItem(inner) => {
+            match *inner {
+                ModuleItem(m) => ItemEnum::Module(Module {
+                    is_crate,
+                    items: ids(m.items, tcx),
+                    is_stripped: true,
+                }),
+                // `convert_item` early returns `None` for stripped items we're not including
+                _ => unreachable!(),
+            }
+        }
+        ExternCrateItem { ref src } => ItemEnum::ExternCrate {
+            name: name.as_ref().unwrap().to_string(),
+            rename: src.map(|x| x.to_string()),
+        },
+    }
+}
+
+impl FromWithTcx for Struct {
+    fn from_tcx(struct_: clean::Struct, tcx: TyCtxt<'_>) -> Self {
+        let fields_stripped = struct_.has_stripped_entries();
+        let clean::Struct { struct_type, generics, fields } = struct_;
+        Struct {
+            struct_type: from_ctor_kind(struct_type),
+            generics: generics.into_tcx(tcx),
+            fields_stripped,
+            fields: ids(fields, tcx),
+            impls: Vec::new(), // Added in JsonRenderer::item
+        }
+    }
+}
+
+impl FromWithTcx for Union {
+    fn from_tcx(union_: clean::Union, tcx: TyCtxt<'_>) -> Self {
+        let fields_stripped = union_.has_stripped_entries();
+        let clean::Union { generics, fields } = union_;
+        Union {
+            generics: generics.into_tcx(tcx),
+            fields_stripped,
+            fields: ids(fields, tcx),
+            impls: Vec::new(), // Added in JsonRenderer::item
+        }
+    }
+}
+
+pub(crate) fn from_ctor_kind(struct_type: CtorKind) -> StructType {
+    match struct_type {
+        CtorKind::Fictive => StructType::Plain,
+        CtorKind::Fn => StructType::Tuple,
+        CtorKind::Const => StructType::Unit,
+    }
+}
+
+pub(crate) fn from_fn_header(header: &rustc_hir::FnHeader) -> Header {
+    Header {
+        async_: header.is_async(),
+        const_: header.is_const(),
+        unsafe_: header.is_unsafe(),
+        abi: convert_abi(header.abi),
+    }
+}
+
+fn convert_abi(a: RustcAbi) -> Abi {
+    match a {
+        RustcAbi::Rust => Abi::Rust,
+        RustcAbi::C { unwind } => Abi::C { unwind },
+        RustcAbi::Cdecl { unwind } => Abi::Cdecl { unwind },
+        RustcAbi::Stdcall { unwind } => Abi::Stdcall { unwind },
+        RustcAbi::Fastcall { unwind } => Abi::Fastcall { unwind },
+        RustcAbi::Aapcs { unwind } => Abi::Aapcs { unwind },
+        RustcAbi::Win64 { unwind } => Abi::Win64 { unwind },
+        RustcAbi::SysV64 { unwind } => Abi::SysV64 { unwind },
+        RustcAbi::System { unwind } => Abi::System { unwind },
+        _ => Abi::Other(a.to_string()),
+    }
+}
+
+impl FromWithTcx for Generics {
+    fn from_tcx(generics: clean::Generics, tcx: TyCtxt<'_>) -> Self {
+        Generics {
+            params: generics.params.into_iter().map(|x| x.into_tcx(tcx)).collect(),
+            where_predicates: generics
+                .where_predicates
+                .into_iter()
+                .map(|x| x.into_tcx(tcx))
+                .collect(),
+        }
+    }
+}
+
+impl FromWithTcx for GenericParamDef {
+    fn from_tcx(generic_param: clean::GenericParamDef, tcx: TyCtxt<'_>) -> Self {
+        GenericParamDef {
+            name: generic_param.name.to_string(),
+            kind: generic_param.kind.into_tcx(tcx),
+        }
+    }
+}
+
+impl FromWithTcx for GenericParamDefKind {
+    fn from_tcx(kind: clean::GenericParamDefKind, tcx: TyCtxt<'_>) -> Self {
+        use clean::GenericParamDefKind::*;
+        match kind {
+            Lifetime { outlives } => GenericParamDefKind::Lifetime {
+                outlives: outlives.into_iter().map(|lt| lt.0.to_string()).collect(),
+            },
+            Type { did: _, bounds, default, synthetic } => GenericParamDefKind::Type {
+                bounds: bounds.into_iter().map(|x| x.into_tcx(tcx)).collect(),
+                default: default.map(|x| (*x).into_tcx(tcx)),
+                synthetic,
+            },
+            Const { did: _, ty, default } => GenericParamDefKind::Const {
+                type_: (*ty).into_tcx(tcx),
+                default: default.map(|x| *x),
+            },
+        }
+    }
+}
+
+impl FromWithTcx for WherePredicate {
+    fn from_tcx(predicate: clean::WherePredicate, tcx: TyCtxt<'_>) -> Self {
+        use clean::WherePredicate::*;
+        match predicate {
+            BoundPredicate { ty, bounds, bound_params } => WherePredicate::BoundPredicate {
+                type_: ty.into_tcx(tcx),
+                bounds: bounds.into_iter().map(|x| x.into_tcx(tcx)).collect(),
+                generic_params: bound_params
+                    .into_iter()
+                    .map(|x| GenericParamDef {
+                        name: x.0.to_string(),
+                        kind: GenericParamDefKind::Lifetime { outlives: vec![] },
+                    })
+                    .collect(),
+            },
+            RegionPredicate { lifetime, bounds } => WherePredicate::RegionPredicate {
+                lifetime: lifetime.0.to_string(),
+                bounds: bounds.into_iter().map(|x| x.into_tcx(tcx)).collect(),
+            },
+            EqPredicate { lhs, rhs } => {
+                WherePredicate::EqPredicate { lhs: lhs.into_tcx(tcx), rhs: rhs.into_tcx(tcx) }
+            }
+        }
+    }
+}
+
+impl FromWithTcx for GenericBound {
+    fn from_tcx(bound: clean::GenericBound, tcx: TyCtxt<'_>) -> Self {
+        use clean::GenericBound::*;
+        match bound {
+            TraitBound(clean::PolyTrait { trait_, generic_params }, modifier) => {
+                // FIXME: should `trait_` be a clean::Path equivalent in JSON?
+                let trait_ = clean::Type::Path { path: trait_ }.into_tcx(tcx);
+                GenericBound::TraitBound {
+                    trait_,
+                    generic_params: generic_params.into_iter().map(|x| x.into_tcx(tcx)).collect(),
+                    modifier: from_trait_bound_modifier(modifier),
+                }
+            }
+            Outlives(lifetime) => GenericBound::Outlives(lifetime.0.to_string()),
+        }
+    }
+}
+
+pub(crate) fn from_trait_bound_modifier(
+    modifier: rustc_hir::TraitBoundModifier,
+) -> TraitBoundModifier {
+    use rustc_hir::TraitBoundModifier::*;
+    match modifier {
+        None => TraitBoundModifier::None,
+        Maybe => TraitBoundModifier::Maybe,
+        MaybeConst => TraitBoundModifier::MaybeConst,
+    }
+}
+
+impl FromWithTcx for Type {
+    fn from_tcx(ty: clean::Type, tcx: TyCtxt<'_>) -> Self {
+        use clean::Type::{
+            Array, BareFunction, BorrowedRef, DynTrait, Generic, ImplTrait, Infer, Primitive,
+            QPath, RawPointer, Slice, Tuple,
+        };
+
+        match ty {
+            clean::Type::Path { path } => Type::ResolvedPath {
+                name: path.whole_name(),
+                id: from_item_id(path.def_id().into(), tcx),
+                args: path.segments.last().map(|args| Box::new(args.clone().args.into_tcx(tcx))),
+                param_names: Vec::new(),
+            },
+            DynTrait(mut bounds, lt) => {
+                let first_trait = bounds.remove(0).trait_;
+
+                Type::ResolvedPath {
+                    name: first_trait.whole_name(),
+                    id: from_item_id(first_trait.def_id().into(), tcx),
+                    args: first_trait
+                        .segments
+                        .last()
+                        .map(|args| Box::new(args.clone().args.into_tcx(tcx))),
+                    param_names: bounds
+                        .into_iter()
+                        .map(|t| {
+                            clean::GenericBound::TraitBound(t, rustc_hir::TraitBoundModifier::None)
+                        })
+                        .chain(lt.map(clean::GenericBound::Outlives))
+                        .map(|bound| bound.into_tcx(tcx))
+                        .collect(),
+                }
+            }
+            Generic(s) => Type::Generic(s.to_string()),
+            Primitive(p) => Type::Primitive(p.as_sym().to_string()),
+            BareFunction(f) => Type::FunctionPointer(Box::new((*f).into_tcx(tcx))),
+            Tuple(t) => Type::Tuple(t.into_iter().map(|x| x.into_tcx(tcx)).collect()),
+            Slice(t) => Type::Slice(Box::new((*t).into_tcx(tcx))),
+            Array(t, s) => Type::Array { type_: Box::new((*t).into_tcx(tcx)), len: s },
+            ImplTrait(g) => Type::ImplTrait(g.into_iter().map(|x| x.into_tcx(tcx)).collect()),
+            Infer => Type::Infer,
+            RawPointer(mutability, type_) => Type::RawPointer {
+                mutable: mutability == ast::Mutability::Mut,
+                type_: Box::new((*type_).into_tcx(tcx)),
+            },
+            BorrowedRef { lifetime, mutability, type_ } => Type::BorrowedRef {
+                lifetime: lifetime.map(|l| l.0.to_string()),
+                mutable: mutability == ast::Mutability::Mut,
+                type_: Box::new((*type_).into_tcx(tcx)),
+            },
+            QPath { assoc, self_type, trait_, .. } => {
+                // FIXME: should `trait_` be a clean::Path equivalent in JSON?
+                let trait_ = clean::Type::Path { path: trait_ }.into_tcx(tcx);
+                Type::QualifiedPath {
+                    name: assoc.name.to_string(),
+                    args: Box::new(assoc.args.clone().into_tcx(tcx)),
+                    self_type: Box::new((*self_type).into_tcx(tcx)),
+                    trait_: Box::new(trait_),
+                }
+            }
+        }
+    }
+}
+
+impl FromWithTcx for Term {
+    fn from_tcx(term: clean::Term, tcx: TyCtxt<'_>) -> Term {
+        match term {
+            clean::Term::Type(ty) => Term::Type(FromWithTcx::from_tcx(ty, tcx)),
+            clean::Term::Constant(c) => Term::Constant(FromWithTcx::from_tcx(c, tcx)),
+        }
+    }
+}
+
+impl FromWithTcx for FunctionPointer {
+    fn from_tcx(bare_decl: clean::BareFunctionDecl, tcx: TyCtxt<'_>) -> Self {
+        let clean::BareFunctionDecl { unsafety, generic_params, decl, abi } = bare_decl;
+        FunctionPointer {
+            header: Header {
+                unsafe_: matches!(unsafety, rustc_hir::Unsafety::Unsafe),
+                const_: false,
+                async_: false,
+                abi: convert_abi(abi),
+            },
+            generic_params: generic_params.into_iter().map(|x| x.into_tcx(tcx)).collect(),
+            decl: decl.into_tcx(tcx),
+        }
+    }
+}
+
+impl FromWithTcx for FnDecl {
+    fn from_tcx(decl: clean::FnDecl, tcx: TyCtxt<'_>) -> Self {
+        let clean::FnDecl { inputs, output, c_variadic } = decl;
+        FnDecl {
+            inputs: inputs
+                .values
+                .into_iter()
+                .map(|arg| (arg.name.to_string(), arg.type_.into_tcx(tcx)))
+                .collect(),
+            output: match output {
+                clean::FnRetTy::Return(t) => Some(t.into_tcx(tcx)),
+                clean::FnRetTy::DefaultReturn => None,
+            },
+            c_variadic,
+        }
+    }
+}
+
+impl FromWithTcx for Trait {
+    fn from_tcx(trait_: clean::Trait, tcx: TyCtxt<'_>) -> Self {
+        let is_auto = trait_.is_auto(tcx);
+        let is_unsafe = trait_.unsafety(tcx) == rustc_hir::Unsafety::Unsafe;
+        let clean::Trait { items, generics, bounds, .. } = trait_;
+        Trait {
+            is_auto,
+            is_unsafe,
+            items: ids(items, tcx),
+            generics: generics.into_tcx(tcx),
+            bounds: bounds.into_iter().map(|x| x.into_tcx(tcx)).collect(),
+            implementations: Vec::new(), // Added in JsonRenderer::item
+        }
+    }
+}
+
+impl FromWithTcx> for Impl {
+    fn from_tcx(impl_: Box, tcx: TyCtxt<'_>) -> Self {
+        let provided_trait_methods = impl_.provided_trait_methods(tcx);
+        let clean::Impl { unsafety, generics, trait_, for_, items, polarity, kind } = *impl_;
+        // FIXME: should `trait_` be a clean::Path equivalent in JSON?
+        let trait_ = trait_.map(|path| clean::Type::Path { path }.into_tcx(tcx));
+        // FIXME: use something like ImplKind in JSON?
+        let (synthetic, blanket_impl) = match kind {
+            clean::ImplKind::Normal | clean::ImplKind::FakeVaradic => (false, None),
+            clean::ImplKind::Auto => (true, None),
+            clean::ImplKind::Blanket(ty) => (false, Some(*ty)),
+        };
+        let negative_polarity = match polarity {
+            ty::ImplPolarity::Positive | ty::ImplPolarity::Reservation => false,
+            ty::ImplPolarity::Negative => true,
+        };
+        Impl {
+            is_unsafe: unsafety == rustc_hir::Unsafety::Unsafe,
+            generics: generics.into_tcx(tcx),
+            provided_trait_methods: provided_trait_methods
+                .into_iter()
+                .map(|x| x.to_string())
+                .collect(),
+            trait_,
+            for_: for_.into_tcx(tcx),
+            items: ids(items, tcx),
+            negative: negative_polarity,
+            synthetic,
+            blanket_impl: blanket_impl.map(|x| x.into_tcx(tcx)),
+        }
+    }
+}
+
+pub(crate) fn from_function(
+    function: Box,
+    header: rustc_hir::FnHeader,
+    tcx: TyCtxt<'_>,
+) -> Function {
+    let clean::Function { decl, generics } = *function;
+    Function {
+        decl: decl.into_tcx(tcx),
+        generics: generics.into_tcx(tcx),
+        header: from_fn_header(&header),
+    }
+}
+
+pub(crate) fn from_function_method(
+    function: Box,
+    has_body: bool,
+    header: rustc_hir::FnHeader,
+    tcx: TyCtxt<'_>,
+) -> Method {
+    let clean::Function { decl, generics } = *function;
+    Method {
+        decl: decl.into_tcx(tcx),
+        generics: generics.into_tcx(tcx),
+        header: from_fn_header(&header),
+        has_body,
+    }
+}
+
+impl FromWithTcx for Enum {
+    fn from_tcx(enum_: clean::Enum, tcx: TyCtxt<'_>) -> Self {
+        let variants_stripped = enum_.has_stripped_entries();
+        let clean::Enum { variants, generics } = enum_;
+        Enum {
+            generics: generics.into_tcx(tcx),
+            variants_stripped,
+            variants: ids(variants, tcx),
+            impls: Vec::new(), // Added in JsonRenderer::item
+        }
+    }
+}
+
+impl FromWithTcx for Struct {
+    fn from_tcx(struct_: clean::VariantStruct, tcx: TyCtxt<'_>) -> Self {
+        let fields_stripped = struct_.has_stripped_entries();
+        let clean::VariantStruct { struct_type, fields } = struct_;
+        Struct {
+            struct_type: from_ctor_kind(struct_type),
+            generics: Generics { params: vec![], where_predicates: vec![] },
+            fields_stripped,
+            fields: ids(fields, tcx),
+            impls: Vec::new(),
+        }
+    }
+}
+
+impl FromWithTcx for Variant {
+    fn from_tcx(variant: clean::Variant, tcx: TyCtxt<'_>) -> Self {
+        use clean::Variant::*;
+        match variant {
+            CLike => Variant::Plain,
+            Tuple(fields) => Variant::Tuple(
+                fields
+                    .into_iter()
+                    .map(|f| {
+                        if let clean::StructFieldItem(ty) = *f.kind {
+                            ty.into_tcx(tcx)
+                        } else {
+                            unreachable!()
+                        }
+                    })
+                    .collect(),
+            ),
+            Struct(s) => Variant::Struct(ids(s.fields, tcx)),
+        }
+    }
+}
+
+impl FromWithTcx for Import {
+    fn from_tcx(import: clean::Import, tcx: TyCtxt<'_>) -> Self {
+        use clean::ImportKind::*;
+        match import.kind {
+            Simple(s) => Import {
+                source: import.source.path.whole_name(),
+                name: s.to_string(),
+                id: import.source.did.map(ItemId::from).map(|i| from_item_id(i, tcx)),
+                glob: false,
+            },
+            Glob => Import {
+                source: import.source.path.whole_name(),
+                name: import
+                    .source
+                    .path
+                    .last_opt()
+                    .unwrap_or_else(|| Symbol::intern("*"))
+                    .to_string(),
+                id: import.source.did.map(ItemId::from).map(|i| from_item_id(i, tcx)),
+                glob: true,
+            },
+        }
+    }
+}
+
+impl FromWithTcx for ProcMacro {
+    fn from_tcx(mac: clean::ProcMacro, _tcx: TyCtxt<'_>) -> Self {
+        ProcMacro {
+            kind: from_macro_kind(mac.kind),
+            helpers: mac.helpers.iter().map(|x| x.to_string()).collect(),
+        }
+    }
+}
+
+pub(crate) fn from_macro_kind(kind: rustc_span::hygiene::MacroKind) -> MacroKind {
+    use rustc_span::hygiene::MacroKind::*;
+    match kind {
+        Bang => MacroKind::Bang,
+        Attr => MacroKind::Attr,
+        Derive => MacroKind::Derive,
+    }
+}
+
+impl FromWithTcx> for Typedef {
+    fn from_tcx(typedef: Box, tcx: TyCtxt<'_>) -> Self {
+        let clean::Typedef { type_, generics, item_type: _ } = *typedef;
+        Typedef { type_: type_.into_tcx(tcx), generics: generics.into_tcx(tcx) }
+    }
+}
+
+impl FromWithTcx for OpaqueTy {
+    fn from_tcx(opaque: clean::OpaqueTy, tcx: TyCtxt<'_>) -> Self {
+        OpaqueTy {
+            bounds: opaque.bounds.into_iter().map(|x| x.into_tcx(tcx)).collect(),
+            generics: opaque.generics.into_tcx(tcx),
+        }
+    }
+}
+
+impl FromWithTcx for Static {
+    fn from_tcx(stat: clean::Static, tcx: TyCtxt<'_>) -> Self {
+        Static {
+            type_: stat.type_.into_tcx(tcx),
+            mutable: stat.mutability == ast::Mutability::Mut,
+            expr: stat.expr.map(|e| print_const_expr(tcx, e)).unwrap_or_default(),
+        }
+    }
+}
+
+impl FromWithTcx for TraitAlias {
+    fn from_tcx(alias: clean::TraitAlias, tcx: TyCtxt<'_>) -> Self {
+        TraitAlias {
+            generics: alias.generics.into_tcx(tcx),
+            params: alias.bounds.into_iter().map(|x| x.into_tcx(tcx)).collect(),
+        }
+    }
+}
+
+impl FromWithTcx for ItemKind {
+    fn from_tcx(kind: ItemType, _tcx: TyCtxt<'_>) -> Self {
+        use ItemType::*;
+        match kind {
+            Module => ItemKind::Module,
+            ExternCrate => ItemKind::ExternCrate,
+            Import => ItemKind::Import,
+            Struct => ItemKind::Struct,
+            Union => ItemKind::Union,
+            Enum => ItemKind::Enum,
+            Function => ItemKind::Function,
+            Typedef => ItemKind::Typedef,
+            OpaqueTy => ItemKind::OpaqueTy,
+            Static => ItemKind::Static,
+            Constant => ItemKind::Constant,
+            Trait => ItemKind::Trait,
+            Impl => ItemKind::Impl,
+            TyMethod | Method => ItemKind::Method,
+            StructField => ItemKind::StructField,
+            Variant => ItemKind::Variant,
+            Macro => ItemKind::Macro,
+            Primitive => ItemKind::Primitive,
+            AssocConst => ItemKind::AssocConst,
+            AssocType => ItemKind::AssocType,
+            ForeignType => ItemKind::ForeignType,
+            Keyword => ItemKind::Keyword,
+            TraitAlias => ItemKind::TraitAlias,
+            ProcAttribute => ItemKind::ProcAttribute,
+            ProcDerive => ItemKind::ProcDerive,
+        }
+    }
+}
+
+fn ids(items: impl IntoIterator, tcx: TyCtxt<'_>) -> Vec {
+    items
+        .into_iter()
+        .filter(|x| !x.is_stripped() && !x.is_keyword())
+        .map(|i| from_item_id_with_name(i.item_id, tcx, i.name))
+        .collect()
+}
diff --git a/src/librustdoc/json/mod.rs b/src/librustdoc/json/mod.rs
new file mode 100644
index 000000000..6364d00d0
--- /dev/null
+++ b/src/librustdoc/json/mod.rs
@@ -0,0 +1,327 @@
+//! Rustdoc's JSON backend
+//!
+//! This module contains the logic for rendering a crate as JSON rather than the normal static HTML
+//! output. See [the RFC](https://github.com/rust-lang/rfcs/pull/2963) and the [`types`] module
+//! docs for usage and details.
+
+mod conversions;
+
+use std::cell::RefCell;
+use std::fs::{create_dir_all, File};
+use std::io::{BufWriter, Write};
+use std::path::PathBuf;
+use std::rc::Rc;
+
+use rustc_data_structures::fx::FxHashMap;
+use rustc_hir::def_id::DefId;
+use rustc_middle::ty::TyCtxt;
+use rustc_session::Session;
+use rustc_span::def_id::LOCAL_CRATE;
+
+use rustdoc_json_types as types;
+
+use crate::clean::types::{ExternalCrate, ExternalLocation};
+use crate::clean::ItemKind;
+use crate::config::RenderOptions;
+use crate::docfs::PathError;
+use crate::error::Error;
+use crate::formats::cache::Cache;
+use crate::formats::FormatRenderer;
+use crate::json::conversions::{from_item_id, from_item_id_with_name, IntoWithTcx};
+use crate::{clean, try_err};
+
+#[derive(Clone)]
+pub(crate) struct JsonRenderer<'tcx> {
+    tcx: TyCtxt<'tcx>,
+    /// A mapping of IDs that contains all local items for this crate which gets output as a top
+    /// level field of the JSON blob.
+    index: Rc>>,
+    /// The directory where the blob will be written to.
+    out_path: PathBuf,
+    cache: Rc,
+}
+
+impl<'tcx> JsonRenderer<'tcx> {
+    fn sess(&self) -> &'tcx Session {
+        self.tcx.sess
+    }
+
+    fn get_trait_implementors(&mut self, id: DefId) -> Vec {
+        Rc::clone(&self.cache)
+            .implementors
+            .get(&id)
+            .map(|implementors| {
+                implementors
+                    .iter()
+                    .map(|i| {
+                        let item = &i.impl_item;
+                        self.item(item.clone()).unwrap();
+                        from_item_id_with_name(item.item_id, self.tcx, item.name)
+                    })
+                    .collect()
+            })
+            .unwrap_or_default()
+    }
+
+    fn get_impls(&mut self, id: DefId) -> Vec {
+        Rc::clone(&self.cache)
+            .impls
+            .get(&id)
+            .map(|impls| {
+                impls
+                    .iter()
+                    .filter_map(|i| {
+                        let item = &i.impl_item;
+
+                        // HACK(hkmatsumoto): For impls of primitive types, we index them
+                        // regardless of whether they're local. This is because users can
+                        // document primitive items in an arbitrary crate by using
+                        // `doc(primitive)`.
+                        let mut is_primitive_impl = false;
+                        if let clean::types::ItemKind::ImplItem(ref impl_) = *item.kind {
+                            if impl_.trait_.is_none() {
+                                if let clean::types::Type::Primitive(_) = impl_.for_ {
+                                    is_primitive_impl = true;
+                                }
+                            }
+                        }
+
+                        if item.item_id.is_local() || is_primitive_impl {
+                            self.item(item.clone()).unwrap();
+                            Some(from_item_id_with_name(item.item_id, self.tcx, item.name))
+                        } else {
+                            None
+                        }
+                    })
+                    .collect()
+            })
+            .unwrap_or_default()
+    }
+
+    fn get_trait_items(&mut self) -> Vec<(types::Id, types::Item)> {
+        Rc::clone(&self.cache)
+            .traits
+            .iter()
+            .filter_map(|(&id, trait_item)| {
+                // only need to synthesize items for external traits
+                if !id.is_local() {
+                    let trait_item = &trait_item.trait_;
+                    trait_item.items.clone().into_iter().for_each(|i| self.item(i).unwrap());
+                    let item_id = from_item_id(id.into(), self.tcx);
+                    Some((
+                        item_id.clone(),
+                        types::Item {
+                            id: item_id,
+                            crate_id: id.krate.as_u32(),
+                            name: self
+                                .cache
+                                .paths
+                                .get(&id)
+                                .unwrap_or_else(|| {
+                                    self.cache
+                                        .external_paths
+                                        .get(&id)
+                                        .expect("Trait should either be in local or external paths")
+                                })
+                                .0
+                                .last()
+                                .map(|s| s.to_string()),
+                            visibility: types::Visibility::Public,
+                            inner: types::ItemEnum::Trait(trait_item.clone().into_tcx(self.tcx)),
+                            span: None,
+                            docs: Default::default(),
+                            links: Default::default(),
+                            attrs: Default::default(),
+                            deprecation: Default::default(),
+                        },
+                    ))
+                } else {
+                    None
+                }
+            })
+            .collect()
+    }
+}
+
+impl<'tcx> FormatRenderer<'tcx> for JsonRenderer<'tcx> {
+    fn descr() -> &'static str {
+        "json"
+    }
+
+    const RUN_ON_MODULE: bool = false;
+
+    fn init(
+        krate: clean::Crate,
+        options: RenderOptions,
+        cache: Cache,
+        tcx: TyCtxt<'tcx>,
+    ) -> Result<(Self, clean::Crate), Error> {
+        debug!("Initializing json renderer");
+        Ok((
+            JsonRenderer {
+                tcx,
+                index: Rc::new(RefCell::new(FxHashMap::default())),
+                out_path: options.output,
+                cache: Rc::new(cache),
+            },
+            krate,
+        ))
+    }
+
+    fn make_child_renderer(&self) -> Self {
+        self.clone()
+    }
+
+    /// Inserts an item into the index. This should be used rather than directly calling insert on
+    /// the hashmap because certain items (traits and types) need to have their mappings for trait
+    /// implementations filled out before they're inserted.
+    fn item(&mut self, item: clean::Item) -> Result<(), Error> {
+        trace!("rendering {} {:?}", item.type_(), item.name);
+
+        // Flatten items that recursively store other items. We include orphaned items from
+        // stripped modules and etc that are otherwise reachable.
+        if let ItemKind::StrippedItem(inner) = &*item.kind {
+            inner.inner_items().for_each(|i| self.item(i.clone()).unwrap());
+        }
+
+        // Flatten items that recursively store other items
+        item.kind.inner_items().for_each(|i| self.item(i.clone()).unwrap());
+
+        let name = item.name;
+        let item_id = item.item_id;
+        if let Some(mut new_item) = self.convert_item(item) {
+            let can_be_ignored = match new_item.inner {
+                types::ItemEnum::Trait(ref mut t) => {
+                    t.implementations = self.get_trait_implementors(item_id.expect_def_id());
+                    false
+                }
+                types::ItemEnum::Struct(ref mut s) => {
+                    s.impls = self.get_impls(item_id.expect_def_id());
+                    false
+                }
+                types::ItemEnum::Enum(ref mut e) => {
+                    e.impls = self.get_impls(item_id.expect_def_id());
+                    false
+                }
+                types::ItemEnum::Union(ref mut u) => {
+                    u.impls = self.get_impls(item_id.expect_def_id());
+                    false
+                }
+
+                types::ItemEnum::Method(_)
+                | types::ItemEnum::AssocConst { .. }
+                | types::ItemEnum::AssocType { .. }
+                | types::ItemEnum::PrimitiveType(_) => true,
+                types::ItemEnum::Module(_)
+                | types::ItemEnum::ExternCrate { .. }
+                | types::ItemEnum::Import(_)
+                | types::ItemEnum::StructField(_)
+                | types::ItemEnum::Variant(_)
+                | types::ItemEnum::Function(_)
+                | types::ItemEnum::TraitAlias(_)
+                | types::ItemEnum::Impl(_)
+                | types::ItemEnum::Typedef(_)
+                | types::ItemEnum::OpaqueTy(_)
+                | types::ItemEnum::Constant(_)
+                | types::ItemEnum::Static(_)
+                | types::ItemEnum::ForeignType
+                | types::ItemEnum::Macro(_)
+                | types::ItemEnum::ProcMacro(_) => false,
+            };
+            let removed = self
+                .index
+                .borrow_mut()
+                .insert(from_item_id_with_name(item_id, self.tcx, name), new_item.clone());
+
+            // FIXME(adotinthevoid): Currently, the index is duplicated. This is a sanity check
+            // to make sure the items are unique. The main place this happens is when an item, is
+            // reexported in more than one place. See `rustdoc-json/reexport/in_root_and_mod`
+            if let Some(old_item) = removed {
+                // In case of generic implementations (like `impl Trait for T {}`), all the
+                // inner items will be duplicated so we can ignore if they are slightly different.
+                if !can_be_ignored {
+                    assert_eq!(old_item, new_item);
+                }
+            }
+        }
+
+        Ok(())
+    }
+
+    fn mod_item_in(&mut self, _item: &clean::Item) -> Result<(), Error> {
+        unreachable!("RUN_ON_MODULE = false should never call mod_item_in")
+    }
+
+    fn after_krate(&mut self) -> Result<(), Error> {
+        debug!("Done with crate");
+
+        for primitive in Rc::clone(&self.cache).primitive_locations.values() {
+            self.get_impls(*primitive);
+        }
+
+        let e = ExternalCrate { crate_num: LOCAL_CRATE };
+
+        let mut index = (*self.index).clone().into_inner();
+        index.extend(self.get_trait_items());
+        // This needs to be the default HashMap for compatibility with the public interface for
+        // rustdoc-json-types
+        #[allow(rustc::default_hash_types)]
+        let output = types::Crate {
+            root: types::Id(format!("0:0:{}", e.name(self.tcx).as_u32())),
+            crate_version: self.cache.crate_version.clone(),
+            includes_private: self.cache.document_private,
+            index: index.into_iter().collect(),
+            paths: self
+                .cache
+                .paths
+                .clone()
+                .into_iter()
+                .chain(self.cache.external_paths.clone().into_iter())
+                .map(|(k, (path, kind))| {
+                    (
+                        from_item_id(k.into(), self.tcx),
+                        types::ItemSummary {
+                            crate_id: k.krate.as_u32(),
+                            path: path.iter().map(|s| s.to_string()).collect(),
+                            kind: kind.into_tcx(self.tcx),
+                        },
+                    )
+                })
+                .collect(),
+            external_crates: self
+                .cache
+                .extern_locations
+                .iter()
+                .map(|(crate_num, external_location)| {
+                    let e = ExternalCrate { crate_num: *crate_num };
+                    (
+                        crate_num.as_u32(),
+                        types::ExternalCrate {
+                            name: e.name(self.tcx).to_string(),
+                            html_root_url: match external_location {
+                                ExternalLocation::Remote(s) => Some(s.clone()),
+                                _ => None,
+                            },
+                        },
+                    )
+                })
+                .collect(),
+            format_version: types::FORMAT_VERSION,
+        };
+        let out_dir = self.out_path.clone();
+        try_err!(create_dir_all(&out_dir), out_dir);
+
+        let mut p = out_dir;
+        p.push(output.index.get(&output.root).unwrap().name.clone().unwrap());
+        p.set_extension("json");
+        let mut file = BufWriter::new(try_err!(File::create(&p), p));
+        serde_json::ser::to_writer(&mut file, &output).unwrap();
+        try_err!(file.flush(), p);
+
+        Ok(())
+    }
+
+    fn cache(&self) -> &Cache {
+        &self.cache
+    }
+}
diff --git a/src/librustdoc/lib.rs b/src/librustdoc/lib.rs
new file mode 100644
index 000000000..92380d124
--- /dev/null
+++ b/src/librustdoc/lib.rs
@@ -0,0 +1,868 @@
+#![doc(
+    html_root_url = "https://doc.rust-lang.org/nightly/",
+    html_playground_url = "https://play.rust-lang.org/"
+)]
+#![feature(rustc_private)]
+#![feature(array_methods)]
+#![feature(assert_matches)]
+#![feature(box_patterns)]
+#![feature(control_flow_enum)]
+#![feature(drain_filter)]
+#![feature(let_chains)]
+#![feature(let_else)]
+#![feature(test)]
+#![feature(never_type)]
+#![feature(once_cell)]
+#![feature(type_ascription)]
+#![feature(iter_intersperse)]
+#![feature(type_alias_impl_trait)]
+#![feature(generic_associated_types)]
+#![recursion_limit = "256"]
+#![warn(rustc::internal)]
+#![allow(clippy::collapsible_if, clippy::collapsible_else_if)]
+#![allow(rustc::potential_query_instability)]
+
+#[macro_use]
+extern crate tracing;
+
+// N.B. these need `extern crate` even in 2018 edition
+// because they're loaded implicitly from the sysroot.
+// The reason they're loaded from the sysroot is because
+// the rustdoc artifacts aren't stored in rustc's cargo target directory.
+// So if `rustc` was specified in Cargo.toml, this would spuriously rebuild crates.
+//
+// Dependencies listed in Cargo.toml do not need `extern crate`.
+
+extern crate rustc_ast;
+extern crate rustc_ast_pretty;
+extern crate rustc_attr;
+extern crate rustc_const_eval;
+extern crate rustc_data_structures;
+extern crate rustc_driver;
+extern crate rustc_errors;
+extern crate rustc_expand;
+extern crate rustc_feature;
+extern crate rustc_hir;
+extern crate rustc_hir_pretty;
+extern crate rustc_index;
+extern crate rustc_infer;
+extern crate rustc_interface;
+extern crate rustc_lexer;
+extern crate rustc_lint;
+extern crate rustc_lint_defs;
+extern crate rustc_macros;
+extern crate rustc_metadata;
+extern crate rustc_middle;
+extern crate rustc_parse;
+extern crate rustc_passes;
+extern crate rustc_resolve;
+extern crate rustc_serialize;
+extern crate rustc_session;
+extern crate rustc_span;
+extern crate rustc_target;
+extern crate rustc_trait_selection;
+extern crate rustc_typeck;
+extern crate test;
+
+// See docs in https://github.com/rust-lang/rust/blob/master/compiler/rustc/src/main.rs
+// about jemalloc.
+#[cfg(feature = "jemalloc")]
+extern crate jemalloc_sys;
+
+use std::default::Default;
+use std::env::{self, VarError};
+use std::io;
+use std::process;
+
+use rustc_driver::abort_on_err;
+use rustc_errors::ErrorGuaranteed;
+use rustc_interface::interface;
+use rustc_middle::ty::TyCtxt;
+use rustc_session::config::{make_crate_type_option, ErrorOutputType, RustcOptGroup};
+use rustc_session::getopts;
+use rustc_session::{early_error, early_warn};
+
+use crate::clean::utils::DOC_RUST_LANG_ORG_CHANNEL;
+use crate::passes::collect_intra_doc_links;
+
+/// A macro to create a FxHashMap.
+///
+/// Example:
+///
+/// ```ignore(cannot-test-this-because-non-exported-macro)
+/// let letters = map!{"a" => "b", "c" => "d"};
+/// ```
+///
+/// Trailing commas are allowed.
+/// Commas between elements are required (even if the expression is a block).
+macro_rules! map {
+    ($( $key: expr => $val: expr ),* $(,)*) => {{
+        let mut map = ::rustc_data_structures::fx::FxHashMap::default();
+        $( map.insert($key, $val); )*
+        map
+    }}
+}
+
+mod clean;
+mod config;
+mod core;
+mod docfs;
+mod doctest;
+mod error;
+mod externalfiles;
+mod fold;
+mod formats;
+// used by the error-index generator, so it needs to be public
+pub mod html;
+mod json;
+pub(crate) mod lint;
+mod markdown;
+mod passes;
+mod scrape_examples;
+mod theme;
+mod visit;
+mod visit_ast;
+mod visit_lib;
+
+pub fn main() {
+    // See docs in https://github.com/rust-lang/rust/blob/master/compiler/rustc/src/main.rs
+    // about jemalloc.
+    #[cfg(feature = "jemalloc")]
+    {
+        use std::os::raw::{c_int, c_void};
+
+        #[used]
+        static _F1: unsafe extern "C" fn(usize, usize) -> *mut c_void = jemalloc_sys::calloc;
+        #[used]
+        static _F2: unsafe extern "C" fn(*mut *mut c_void, usize, usize) -> c_int =
+            jemalloc_sys::posix_memalign;
+        #[used]
+        static _F3: unsafe extern "C" fn(usize, usize) -> *mut c_void = jemalloc_sys::aligned_alloc;
+        #[used]
+        static _F4: unsafe extern "C" fn(usize) -> *mut c_void = jemalloc_sys::malloc;
+        #[used]
+        static _F5: unsafe extern "C" fn(*mut c_void, usize) -> *mut c_void = jemalloc_sys::realloc;
+        #[used]
+        static _F6: unsafe extern "C" fn(*mut c_void) = jemalloc_sys::free;
+
+        #[cfg(target_os = "macos")]
+        {
+            extern "C" {
+                fn _rjem_je_zone_register();
+            }
+
+            #[used]
+            static _F7: unsafe extern "C" fn() = _rjem_je_zone_register;
+        }
+    }
+
+    rustc_driver::set_sigpipe_handler();
+    rustc_driver::install_ice_hook();
+
+    // When using CI artifacts (with `download_stage1 = true`), tracing is unconditionally built
+    // with `--features=static_max_level_info`, which disables almost all rustdoc logging. To avoid
+    // this, compile our own version of `tracing` that logs all levels.
+    // NOTE: this compiles both versions of tracing unconditionally, because
+    // - The compile time hit is not that bad, especially compared to rustdoc's incremental times, and
+    // - Otherwise, there's no warning that logging is being ignored when `download_stage1 = true`.
+    // NOTE: The reason this doesn't show double logging when `download_stage1 = false` and
+    // `debug_logging = true` is because all rustc logging goes to its version of tracing (the one
+    // in the sysroot), and all of rustdoc's logging goes to its version (the one in Cargo.toml).
+    init_logging();
+    rustc_driver::init_env_logger("RUSTDOC_LOG");
+
+    let exit_code = rustc_driver::catch_with_exit_code(|| match get_args() {
+        Some(args) => main_args(&args),
+        _ => Err(ErrorGuaranteed::unchecked_claim_error_was_emitted()),
+    });
+    process::exit(exit_code);
+}
+
+fn init_logging() {
+    let color_logs = match std::env::var("RUSTDOC_LOG_COLOR").as_deref() {
+        Ok("always") => true,
+        Ok("never") => false,
+        Ok("auto") | Err(VarError::NotPresent) => atty::is(atty::Stream::Stdout),
+        Ok(value) => early_error(
+            ErrorOutputType::default(),
+            &format!("invalid log color value '{}': expected one of always, never, or auto", value),
+        ),
+        Err(VarError::NotUnicode(value)) => early_error(
+            ErrorOutputType::default(),
+            &format!(
+                "invalid log color value '{}': expected one of always, never, or auto",
+                value.to_string_lossy()
+            ),
+        ),
+    };
+    let filter = tracing_subscriber::EnvFilter::from_env("RUSTDOC_LOG");
+    let layer = tracing_tree::HierarchicalLayer::default()
+        .with_writer(io::stderr)
+        .with_indent_lines(true)
+        .with_ansi(color_logs)
+        .with_targets(true)
+        .with_wraparound(10)
+        .with_verbose_exit(true)
+        .with_verbose_entry(true)
+        .with_indent_amount(2);
+    #[cfg(parallel_compiler)]
+    let layer = layer.with_thread_ids(true).with_thread_names(true);
+
+    use tracing_subscriber::layer::SubscriberExt;
+    let subscriber = tracing_subscriber::Registry::default().with(filter).with(layer);
+    tracing::subscriber::set_global_default(subscriber).unwrap();
+}
+
+fn get_args() -> Option> {
+    env::args_os()
+        .enumerate()
+        .map(|(i, arg)| {
+            arg.into_string()
+                .map_err(|arg| {
+                    early_warn(
+                        ErrorOutputType::default(),
+                        &format!("Argument {} is not valid Unicode: {:?}", i, arg),
+                    );
+                })
+                .ok()
+        })
+        .collect()
+}
+
+fn opts() -> Vec {
+    let stable: fn(_, fn(&mut getopts::Options) -> &mut _) -> _ = RustcOptGroup::stable;
+    let unstable: fn(_, fn(&mut getopts::Options) -> &mut _) -> _ = RustcOptGroup::unstable;
+    vec![
+        stable("h", |o| o.optflagmulti("h", "help", "show this help message")),
+        stable("V", |o| o.optflagmulti("V", "version", "print rustdoc's version")),
+        stable("v", |o| o.optflagmulti("v", "verbose", "use verbose output")),
+        stable("w", |o| o.optopt("w", "output-format", "the output type to write", "[html]")),
+        stable("output", |o| {
+            o.optopt(
+                "",
+                "output",
+                "Which directory to place the output. \
+                 This option is deprecated, use --out-dir instead.",
+                "PATH",
+            )
+        }),
+        stable("o", |o| o.optopt("o", "out-dir", "which directory to place the output", "PATH")),
+        stable("crate-name", |o| {
+            o.optopt("", "crate-name", "specify the name of this crate", "NAME")
+        }),
+        make_crate_type_option(),
+        stable("L", |o| {
+            o.optmulti("L", "library-path", "directory to add to crate search path", "DIR")
+        }),
+        stable("cfg", |o| o.optmulti("", "cfg", "pass a --cfg to rustc", "")),
+        unstable("check-cfg", |o| o.optmulti("", "check-cfg", "pass a --check-cfg to rustc", "")),
+        stable("extern", |o| o.optmulti("", "extern", "pass an --extern to rustc", "NAME[=PATH]")),
+        unstable("extern-html-root-url", |o| {
+            o.optmulti(
+                "",
+                "extern-html-root-url",
+                "base URL to use for dependencies; for example, \
+                 \"std=/doc\" links std::vec::Vec to /doc/std/vec/struct.Vec.html",
+                "NAME=URL",
+            )
+        }),
+        unstable("extern-html-root-takes-precedence", |o| {
+            o.optflagmulti(
+                "",
+                "extern-html-root-takes-precedence",
+                "give precedence to `--extern-html-root-url`, not `html_root_url`",
+            )
+        }),
+        stable("C", |o| {
+            o.optmulti("C", "codegen", "pass a codegen option to rustc", "OPT[=VALUE]")
+        }),
+        stable("document-private-items", |o| {
+            o.optflagmulti("", "document-private-items", "document private items")
+        }),
+        unstable("document-hidden-items", |o| {
+            o.optflagmulti("", "document-hidden-items", "document items that have doc(hidden)")
+        }),
+        stable("test", |o| o.optflagmulti("", "test", "run code examples as tests")),
+        stable("test-args", |o| {
+            o.optmulti("", "test-args", "arguments to pass to the test runner", "ARGS")
+        }),
+        unstable("test-run-directory", |o| {
+            o.optopt(
+                "",
+                "test-run-directory",
+                "The working directory in which to run tests",
+                "PATH",
+            )
+        }),
+        stable("target", |o| o.optopt("", "target", "target triple to document", "TRIPLE")),
+        stable("markdown-css", |o| {
+            o.optmulti(
+                "",
+                "markdown-css",
+                "CSS files to include via  in a rendered Markdown file",
+                "FILES",
+            )
+        }),
+        stable("html-in-header", |o| {
+            o.optmulti(
+                "",
+                "html-in-header",
+                "files to include inline in the  section of a rendered Markdown file \
+                 or generated documentation",
+                "FILES",
+            )
+        }),
+        stable("html-before-content", |o| {
+            o.optmulti(
+                "",
+                "html-before-content",
+                "files to include inline between  and the content of a rendered \
+                 Markdown file or generated documentation",
+                "FILES",
+            )
+        }),
+        stable("html-after-content", |o| {
+            o.optmulti(
+                "",
+                "html-after-content",
+                "files to include inline between the content and  of a rendered \
+                 Markdown file or generated documentation",
+                "FILES",
+            )
+        }),
+        unstable("markdown-before-content", |o| {
+            o.optmulti(
+                "",
+                "markdown-before-content",
+                "files to include inline between  and the content of a rendered \
+                 Markdown file or generated documentation",
+                "FILES",
+            )
+        }),
+        unstable("markdown-after-content", |o| {
+            o.optmulti(
+                "",
+                "markdown-after-content",
+                "files to include inline between the content and  of a rendered \
+                 Markdown file or generated documentation",
+                "FILES",
+            )
+        }),
+        stable("markdown-playground-url", |o| {
+            o.optopt("", "markdown-playground-url", "URL to send code snippets to", "URL")
+        }),
+        stable("markdown-no-toc", |o| {
+            o.optflagmulti("", "markdown-no-toc", "don't include table of contents")
+        }),
+        stable("e", |o| {
+            o.optopt(
+                "e",
+                "extend-css",
+                "To add some CSS rules with a given file to generate doc with your \
+                 own theme. However, your theme might break if the rustdoc's generated HTML \
+                 changes, so be careful!",
+                "PATH",
+            )
+        }),
+        unstable("Z", |o| {
+            o.optmulti("Z", "", "unstable / perma-unstable options (only on nightly build)", "FLAG")
+        }),
+        stable("sysroot", |o| o.optopt("", "sysroot", "Override the system root", "PATH")),
+        unstable("playground-url", |o| {
+            o.optopt(
+                "",
+                "playground-url",
+                "URL to send code snippets to, may be reset by --markdown-playground-url \
+                 or `#![doc(html_playground_url=...)]`",
+                "URL",
+            )
+        }),
+        unstable("display-doctest-warnings", |o| {
+            o.optflagmulti(
+                "",
+                "display-doctest-warnings",
+                "show warnings that originate in doctests",
+            )
+        }),
+        stable("crate-version", |o| {
+            o.optopt("", "crate-version", "crate version to print into documentation", "VERSION")
+        }),
+        unstable("sort-modules-by-appearance", |o| {
+            o.optflagmulti(
+                "",
+                "sort-modules-by-appearance",
+                "sort modules by where they appear in the program, rather than alphabetically",
+            )
+        }),
+        stable("default-theme", |o| {
+            o.optopt(
+                "",
+                "default-theme",
+                "Set the default theme. THEME should be the theme name, generally lowercase. \
+                 If an unknown default theme is specified, the builtin default is used. \
+                 The set of themes, and the rustdoc built-in default, are not stable.",
+                "THEME",
+            )
+        }),
+        unstable("default-setting", |o| {
+            o.optmulti(
+                "",
+                "default-setting",
+                "Default value for a rustdoc setting (used when \"rustdoc-SETTING\" is absent \
+                 from web browser Local Storage). If VALUE is not supplied, \"true\" is used. \
+                 Supported SETTINGs and VALUEs are not documented and not stable.",
+                "SETTING[=VALUE]",
+            )
+        }),
+        stable("theme", |o| {
+            o.optmulti(
+                "",
+                "theme",
+                "additional themes which will be added to the generated docs",
+                "FILES",
+            )
+        }),
+        stable("check-theme", |o| {
+            o.optmulti("", "check-theme", "check if given theme is valid", "FILES")
+        }),
+        unstable("resource-suffix", |o| {
+            o.optopt(
+                "",
+                "resource-suffix",
+                "suffix to add to CSS and JavaScript files, e.g., \"light.css\" will become \
+                 \"light-suffix.css\"",
+                "PATH",
+            )
+        }),
+        stable("edition", |o| {
+            o.optopt(
+                "",
+                "edition",
+                "edition to use when compiling rust code (default: 2015)",
+                "EDITION",
+            )
+        }),
+        stable("color", |o| {
+            o.optopt(
+                "",
+                "color",
+                "Configure coloring of output:
+                                          auto   = colorize, if output goes to a tty (default);
+                                          always = always colorize output;
+                                          never  = never colorize output",
+                "auto|always|never",
+            )
+        }),
+        stable("error-format", |o| {
+            o.optopt(
+                "",
+                "error-format",
+                "How errors and other messages are produced",
+                "human|json|short",
+            )
+        }),
+        unstable("diagnostic-width", |o| {
+            o.optopt(
+                "",
+                "diagnostic-width",
+                "Provide width of the output for truncated error messages",
+                "WIDTH",
+            )
+        }),
+        stable("json", |o| {
+            o.optopt("", "json", "Configure the structure of JSON diagnostics", "CONFIG")
+        }),
+        unstable("disable-minification", |o| {
+            o.optflagmulti("", "disable-minification", "Disable minification applied on JS files")
+        }),
+        stable("allow", |o| o.optmulti("A", "allow", "Set lint allowed", "LINT")),
+        stable("warn", |o| o.optmulti("W", "warn", "Set lint warnings", "LINT")),
+        stable("force-warn", |o| o.optmulti("", "force-warn", "Set lint force-warn", "LINT")),
+        stable("deny", |o| o.optmulti("D", "deny", "Set lint denied", "LINT")),
+        stable("forbid", |o| o.optmulti("F", "forbid", "Set lint forbidden", "LINT")),
+        stable("cap-lints", |o| {
+            o.optmulti(
+                "",
+                "cap-lints",
+                "Set the most restrictive lint level. \
+                 More restrictive lints are capped at this \
+                 level. By default, it is at `forbid` level.",
+                "LEVEL",
+            )
+        }),
+        unstable("index-page", |o| {
+            o.optopt("", "index-page", "Markdown file to be used as index page", "PATH")
+        }),
+        unstable("enable-index-page", |o| {
+            o.optflagmulti("", "enable-index-page", "To enable generation of the index page")
+        }),
+        unstable("static-root-path", |o| {
+            o.optopt(
+                "",
+                "static-root-path",
+                "Path string to force loading static files from in output pages. \
+                 If not set, uses combinations of '../' to reach the documentation root.",
+                "PATH",
+            )
+        }),
+        unstable("disable-per-crate-search", |o| {
+            o.optflagmulti(
+                "",
+                "disable-per-crate-search",
+                "disables generating the crate selector on the search box",
+            )
+        }),
+        unstable("persist-doctests", |o| {
+            o.optopt(
+                "",
+                "persist-doctests",
+                "Directory to persist doctest executables into",
+                "PATH",
+            )
+        }),
+        unstable("show-coverage", |o| {
+            o.optflagmulti(
+                "",
+                "show-coverage",
+                "calculate percentage of public items with documentation",
+            )
+        }),
+        unstable("enable-per-target-ignores", |o| {
+            o.optflagmulti(
+                "",
+                "enable-per-target-ignores",
+                "parse ignore-foo for ignoring doctests on a per-target basis",
+            )
+        }),
+        unstable("runtool", |o| {
+            o.optopt(
+                "",
+                "runtool",
+                "",
+                "The tool to run tests with when building for a different target than host",
+            )
+        }),
+        unstable("runtool-arg", |o| {
+            o.optmulti(
+                "",
+                "runtool-arg",
+                "",
+                "One (of possibly many) arguments to pass to the runtool",
+            )
+        }),
+        unstable("test-builder", |o| {
+            o.optopt("", "test-builder", "The rustc-like binary to use as the test builder", "PATH")
+        }),
+        unstable("check", |o| o.optflagmulti("", "check", "Run rustdoc checks")),
+        unstable("generate-redirect-map", |o| {
+            o.optflagmulti(
+                "",
+                "generate-redirect-map",
+                "Generate JSON file at the top level instead of generating HTML redirection files",
+            )
+        }),
+        unstable("emit", |o| {
+            o.optmulti(
+                "",
+                "emit",
+                "Comma separated list of types of output for rustdoc to emit",
+                "[unversioned-shared-resources,toolchain-shared-resources,invocation-specific]",
+            )
+        }),
+        unstable("no-run", |o| {
+            o.optflagmulti("", "no-run", "Compile doctests without running them")
+        }),
+        unstable("show-type-layout", |o| {
+            o.optflagmulti("", "show-type-layout", "Include the memory layout of types in the docs")
+        }),
+        unstable("nocapture", |o| {
+            o.optflag("", "nocapture", "Don't capture stdout and stderr of tests")
+        }),
+        unstable("generate-link-to-definition", |o| {
+            o.optflag(
+                "",
+                "generate-link-to-definition",
+                "Make the identifiers in the HTML source code pages navigable",
+            )
+        }),
+        unstable("scrape-examples-output-path", |o| {
+            o.optopt(
+                "",
+                "scrape-examples-output-path",
+                "",
+                "collect function call information and output at the given path",
+            )
+        }),
+        unstable("scrape-examples-target-crate", |o| {
+            o.optmulti(
+                "",
+                "scrape-examples-target-crate",
+                "",
+                "collect function call information for functions from the target crate",
+            )
+        }),
+        unstable("scrape-tests", |o| {
+            o.optflag("", "scrape-tests", "Include test code when scraping examples")
+        }),
+        unstable("with-examples", |o| {
+            o.optmulti(
+                "",
+                "with-examples",
+                "",
+                "path to function call information (for displaying examples in the documentation)",
+            )
+        }),
+        // deprecated / removed options
+        stable("plugin-path", |o| {
+            o.optmulti(
+                "",
+                "plugin-path",
+                "removed, see issue #44136  \
+                for more information",
+                "DIR",
+            )
+        }),
+        stable("passes", |o| {
+            o.optmulti(
+                "",
+                "passes",
+                "removed, see issue #44136  \
+                for more information",
+                "PASSES",
+            )
+        }),
+        stable("plugins", |o| {
+            o.optmulti(
+                "",
+                "plugins",
+                "removed, see issue #44136  \
+                for more information",
+                "PLUGINS",
+            )
+        }),
+        stable("no-default", |o| {
+            o.optflagmulti(
+                "",
+                "no-defaults",
+                "removed, see issue #44136  \
+                for more information",
+            )
+        }),
+        stable("r", |o| {
+            o.optopt(
+                "r",
+                "input-format",
+                "removed, see issue #44136  \
+                for more information",
+                "[rust]",
+            )
+        }),
+    ]
+}
+
+fn usage(argv0: &str) {
+    let mut options = getopts::Options::new();
+    for option in opts() {
+        (option.apply)(&mut options);
+    }
+    println!("{}", options.usage(&format!("{} [options] ", argv0)));
+    println!("    @path               Read newline separated options from `path`\n");
+    println!(
+        "More information available at {}/rustdoc/what-is-rustdoc.html",
+        DOC_RUST_LANG_ORG_CHANNEL
+    );
+}
+
+/// A result type used by several functions under `main()`.
+type MainResult = Result<(), ErrorGuaranteed>;
+
+fn main_args(at_args: &[String]) -> MainResult {
+    let args = rustc_driver::args::arg_expand_all(at_args);
+
+    let mut options = getopts::Options::new();
+    for option in opts() {
+        (option.apply)(&mut options);
+    }
+    let matches = match options.parse(&args[1..]) {
+        Ok(m) => m,
+        Err(err) => {
+            early_error(ErrorOutputType::default(), &err.to_string());
+        }
+    };
+
+    // Note that we discard any distinction between different non-zero exit
+    // codes from `from_matches` here.
+    let options = match config::Options::from_matches(&matches, args) {
+        Ok(opts) => opts,
+        Err(code) => {
+            return if code == 0 {
+                Ok(())
+            } else {
+                Err(ErrorGuaranteed::unchecked_claim_error_was_emitted())
+            };
+        }
+    };
+    rustc_interface::util::run_in_thread_pool_with_globals(
+        options.edition,
+        1, // this runs single-threaded, even in a parallel compiler
+        move || main_options(options),
+    )
+}
+
+fn wrap_return(diag: &rustc_errors::Handler, res: Result<(), String>) -> MainResult {
+    match res {
+        Ok(()) => Ok(()),
+        Err(err) => {
+            let reported = diag.struct_err(&err).emit();
+            Err(reported)
+        }
+    }
+}
+
+fn run_renderer<'tcx, T: formats::FormatRenderer<'tcx>>(
+    krate: clean::Crate,
+    renderopts: config::RenderOptions,
+    cache: formats::cache::Cache,
+    tcx: TyCtxt<'tcx>,
+) -> MainResult {
+    match formats::run_format::(krate, renderopts, cache, tcx) {
+        Ok(_) => Ok(()),
+        Err(e) => {
+            let mut msg =
+                tcx.sess.struct_err(&format!("couldn't generate documentation: {}", e.error));
+            let file = e.file.display().to_string();
+            if !file.is_empty() {
+                msg.note(&format!("failed to create or modify \"{}\"", file));
+            }
+            Err(msg.emit())
+        }
+    }
+}
+
+fn main_options(options: config::Options) -> MainResult {
+    let diag = core::new_handler(
+        options.error_format,
+        None,
+        options.diagnostic_width,
+        &options.unstable_opts,
+    );
+
+    match (options.should_test, options.markdown_input()) {
+        (true, true) => return wrap_return(&diag, markdown::test(options)),
+        (true, false) => return doctest::run(options),
+        (false, true) => {
+            return wrap_return(
+                &diag,
+                markdown::render(&options.input, options.render_options, options.edition),
+            );
+        }
+        (false, false) => {}
+    }
+
+    // need to move these items separately because we lose them by the time the closure is called,
+    // but we can't create the Handler ahead of time because it's not Send
+    let show_coverage = options.show_coverage;
+    let run_check = options.run_check;
+
+    // First, parse the crate and extract all relevant information.
+    info!("starting to run rustc");
+
+    // Interpret the input file as a rust source file, passing it through the
+    // compiler all the way through the analysis passes. The rustdoc output is
+    // then generated from the cleaned AST of the crate. This runs all the
+    // plug/cleaning passes.
+    let crate_version = options.crate_version.clone();
+
+    let output_format = options.output_format;
+    // FIXME: fix this clone (especially render_options)
+    let externs = options.externs.clone();
+    let render_options = options.render_options.clone();
+    let scrape_examples_options = options.scrape_examples_options.clone();
+    let document_private = options.render_options.document_private;
+    let config = core::create_config(options);
+
+    interface::create_compiler_and_run(config, |compiler| {
+        let sess = compiler.session();
+
+        if sess.opts.describe_lints {
+            let mut lint_store = rustc_lint::new_lint_store(
+                sess.opts.unstable_opts.no_interleave_lints,
+                sess.enable_internal_lints(),
+            );
+            let registered_lints = if let Some(register_lints) = compiler.register_lints() {
+                register_lints(sess, &mut lint_store);
+                true
+            } else {
+                false
+            };
+            rustc_driver::describe_lints(sess, &lint_store, registered_lints);
+            return Ok(());
+        }
+
+        compiler.enter(|queries| {
+            // We need to hold on to the complete resolver, so we cause everything to be
+            // cloned for the analysis passes to use. Suboptimal, but necessary in the
+            // current architecture.
+            // FIXME(#83761): Resolver cloning can lead to inconsistencies between data in the
+            // two copies because one of the copies can be modified after `TyCtxt` construction.
+            let (resolver, resolver_caches) = {
+                let (krate, resolver, _) = &*abort_on_err(queries.expansion(), sess).peek();
+                let resolver_caches = resolver.borrow_mut().access(|resolver| {
+                    collect_intra_doc_links::early_resolve_intra_doc_links(
+                        resolver,
+                        sess,
+                        krate,
+                        externs,
+                        document_private,
+                    )
+                });
+                (resolver.clone(), resolver_caches)
+            };
+
+            if sess.diagnostic().has_errors_or_lint_errors().is_some() {
+                sess.fatal("Compilation failed, aborting rustdoc");
+            }
+
+            let mut global_ctxt = abort_on_err(queries.global_ctxt(), sess).peek_mut();
+
+            global_ctxt.enter(|tcx| {
+                let (krate, render_opts, mut cache) = sess.time("run_global_ctxt", || {
+                    core::run_global_ctxt(
+                        tcx,
+                        resolver,
+                        resolver_caches,
+                        show_coverage,
+                        render_options,
+                        output_format,
+                    )
+                });
+                info!("finished with rustc");
+
+                if let Some(options) = scrape_examples_options {
+                    return scrape_examples::run(krate, render_opts, cache, tcx, options);
+                }
+
+                cache.crate_version = crate_version;
+
+                if show_coverage {
+                    // if we ran coverage, bail early, we don't need to also generate docs at this point
+                    // (also we didn't load in any of the useful passes)
+                    return Ok(());
+                } else if run_check {
+                    // Since we're in "check" mode, no need to generate anything beyond this point.
+                    return Ok(());
+                }
+
+                info!("going to format");
+                match output_format {
+                    config::OutputFormat::Html => sess.time("render_html", || {
+                        run_renderer::>(krate, render_opts, cache, tcx)
+                    }),
+                    config::OutputFormat::Json => sess.time("render_json", || {
+                        run_renderer::>(krate, render_opts, cache, tcx)
+                    }),
+                }
+            })
+        })
+    })
+}
diff --git a/src/librustdoc/lint.rs b/src/librustdoc/lint.rs
new file mode 100644
index 000000000..240aec52c
--- /dev/null
+++ b/src/librustdoc/lint.rs
@@ -0,0 +1,202 @@
+use rustc_data_structures::fx::FxHashMap;
+use rustc_lint::LintStore;
+use rustc_lint_defs::{declare_tool_lint, Lint, LintId};
+use rustc_session::{lint, Session};
+
+use std::sync::LazyLock as Lazy;
+
+/// This function is used to setup the lint initialization. By default, in rustdoc, everything
+/// is "allowed". Depending if we run in test mode or not, we want some of them to be at their
+/// default level. For example, the "INVALID_CODEBLOCK_ATTRIBUTES" lint is activated in both
+/// modes.
+///
+/// A little detail easy to forget is that there is a way to set the lint level for all lints
+/// through the "WARNINGS" lint. To prevent this to happen, we set it back to its "normal" level
+/// inside this function.
+///
+/// It returns a tuple containing:
+///  * Vector of tuples of lints' name and their associated "max" level
+///  * HashMap of lint id with their associated "max" level
+pub(crate) fn init_lints(
+    mut allowed_lints: Vec,
+    lint_opts: Vec<(String, lint::Level)>,
+    filter_call: F,
+) -> (Vec<(String, lint::Level)>, FxHashMap)
+where
+    F: Fn(&lint::Lint) -> Option<(String, lint::Level)>,
+{
+    let warnings_lint_name = lint::builtin::WARNINGS.name;
+
+    allowed_lints.push(warnings_lint_name.to_owned());
+    allowed_lints.extend(lint_opts.iter().map(|(lint, _)| lint).cloned());
+
+    let lints = || {
+        lint::builtin::HardwiredLints::get_lints()
+            .into_iter()
+            .chain(rustc_lint::SoftLints::get_lints().into_iter())
+    };
+
+    let lint_opts = lints()
+        .filter_map(|lint| {
+            // Permit feature-gated lints to avoid feature errors when trying to
+            // allow all lints.
+            if lint.feature_gate.is_some() || allowed_lints.iter().any(|l| lint.name == l) {
+                None
+            } else {
+                filter_call(lint)
+            }
+        })
+        .chain(lint_opts.into_iter())
+        .collect::>();
+
+    let lint_caps = lints()
+        .filter_map(|lint| {
+            // We don't want to allow *all* lints so let's ignore
+            // those ones.
+            if allowed_lints.iter().any(|l| lint.name == l) {
+                None
+            } else {
+                Some((lint::LintId::of(lint), lint::Allow))
+            }
+        })
+        .collect();
+    (lint_opts, lint_caps)
+}
+
+macro_rules! declare_rustdoc_lint {
+    ($(#[$attr:meta])* $name: ident, $level: ident, $descr: literal $(,)?) => {
+        declare_tool_lint! {
+            $(#[$attr])* pub rustdoc::$name, $level, $descr
+        }
+    }
+}
+
+declare_rustdoc_lint! {
+    /// The `broken_intra_doc_links` lint detects failures in resolving
+    /// intra-doc link targets. This is a `rustdoc` only lint, see the
+    /// documentation in the [rustdoc book].
+    ///
+    /// [rustdoc book]: ../../../rustdoc/lints.html#broken_intra_doc_links
+    BROKEN_INTRA_DOC_LINKS,
+    Warn,
+    "failures in resolving intra-doc link targets"
+}
+
+declare_rustdoc_lint! {
+    /// This is a subset of `broken_intra_doc_links` that warns when linking from
+    /// a public item to a private one. This is a `rustdoc` only lint, see the
+    /// documentation in the [rustdoc book].
+    ///
+    /// [rustdoc book]: ../../../rustdoc/lints.html#private_intra_doc_links
+    PRIVATE_INTRA_DOC_LINKS,
+    Warn,
+    "linking from a public item to a private one"
+}
+
+declare_rustdoc_lint! {
+    /// The `invalid_codeblock_attributes` lint detects code block attributes
+    /// in documentation examples that have potentially mis-typed values. This
+    /// is a `rustdoc` only lint, see the documentation in the [rustdoc book].
+    ///
+    /// [rustdoc book]: ../../../rustdoc/lints.html#invalid_codeblock_attributes
+    INVALID_CODEBLOCK_ATTRIBUTES,
+    Warn,
+    "codeblock attribute looks a lot like a known one"
+}
+
+declare_rustdoc_lint! {
+    /// The `missing_crate_level_docs` lint detects if documentation is
+    /// missing at the crate root. This is a `rustdoc` only lint, see the
+    /// documentation in the [rustdoc book].
+    ///
+    /// [rustdoc book]: ../../../rustdoc/lints.html#missing_crate_level_docs
+    MISSING_CRATE_LEVEL_DOCS,
+    Allow,
+    "detects crates with no crate-level documentation"
+}
+
+declare_rustdoc_lint! {
+    /// The `missing_doc_code_examples` lint detects publicly-exported items
+    /// without code samples in their documentation. This is a `rustdoc` only
+    /// lint, see the documentation in the [rustdoc book].
+    ///
+    /// [rustdoc book]: ../../../rustdoc/lints.html#missing_doc_code_examples
+    MISSING_DOC_CODE_EXAMPLES,
+    Allow,
+    "detects publicly-exported items without code samples in their documentation"
+}
+
+declare_rustdoc_lint! {
+    /// The `private_doc_tests` lint detects code samples in docs of private
+    /// items not documented by `rustdoc`. This is a `rustdoc` only lint, see
+    /// the documentation in the [rustdoc book].
+    ///
+    /// [rustdoc book]: ../../../rustdoc/lints.html#private_doc_tests
+    PRIVATE_DOC_TESTS,
+    Allow,
+    "detects code samples in docs of private items not documented by rustdoc"
+}
+
+declare_rustdoc_lint! {
+    /// The `invalid_html_tags` lint detects invalid HTML tags. This is a
+    /// `rustdoc` only lint, see the documentation in the [rustdoc book].
+    ///
+    /// [rustdoc book]: ../../../rustdoc/lints.html#invalid_html_tags
+    INVALID_HTML_TAGS,
+    Allow,
+    "detects invalid HTML tags in doc comments"
+}
+
+declare_rustdoc_lint! {
+    /// The `bare_urls` lint detects when a URL is not a hyperlink.
+    /// This is a `rustdoc` only lint, see the documentation in the [rustdoc book].
+    ///
+    /// [rustdoc book]: ../../../rustdoc/lints.html#bare_urls
+    BARE_URLS,
+    Warn,
+    "detects URLs that are not hyperlinks"
+}
+
+declare_rustdoc_lint! {
+   /// The `invalid_rust_codeblocks` lint detects Rust code blocks in
+   /// documentation examples that are invalid (e.g. empty, not parsable as
+   /// Rust code). This is a `rustdoc` only lint, see the documentation in the
+   /// [rustdoc book].
+   ///
+   /// [rustdoc book]: ../../../rustdoc/lints.html#invalid_rust_codeblocks
+   INVALID_RUST_CODEBLOCKS,
+   Warn,
+   "codeblock could not be parsed as valid Rust or is empty"
+}
+
+pub(crate) static RUSTDOC_LINTS: Lazy> = Lazy::new(|| {
+    vec![
+        BROKEN_INTRA_DOC_LINKS,
+        PRIVATE_INTRA_DOC_LINKS,
+        MISSING_DOC_CODE_EXAMPLES,
+        PRIVATE_DOC_TESTS,
+        INVALID_CODEBLOCK_ATTRIBUTES,
+        INVALID_RUST_CODEBLOCKS,
+        INVALID_HTML_TAGS,
+        BARE_URLS,
+        MISSING_CRATE_LEVEL_DOCS,
+    ]
+});
+
+pub(crate) fn register_lints(_sess: &Session, lint_store: &mut LintStore) {
+    lint_store.register_lints(&**RUSTDOC_LINTS);
+    lint_store.register_group(
+        true,
+        "rustdoc::all",
+        Some("rustdoc"),
+        RUSTDOC_LINTS.iter().map(|&lint| LintId::of(lint)).collect(),
+    );
+    for lint in &*RUSTDOC_LINTS {
+        let name = lint.name_lower();
+        lint_store.register_renamed(&name.replace("rustdoc::", ""), &name);
+    }
+    lint_store
+        .register_renamed("intra_doc_link_resolution_failure", "rustdoc::broken_intra_doc_links");
+    lint_store.register_renamed("non_autolinks", "rustdoc::bare_urls");
+    lint_store.register_renamed("rustdoc::non_autolinks", "rustdoc::bare_urls");
+}
diff --git a/src/librustdoc/markdown.rs b/src/librustdoc/markdown.rs
new file mode 100644
index 000000000..0b557ef24
--- /dev/null
+++ b/src/librustdoc/markdown.rs
@@ -0,0 +1,151 @@
+use std::fmt::Write as _;
+use std::fs::{create_dir_all, read_to_string, File};
+use std::io::prelude::*;
+use std::path::Path;
+
+use rustc_span::edition::Edition;
+use rustc_span::source_map::DUMMY_SP;
+use rustc_span::Symbol;
+
+use crate::config::{Options, RenderOptions};
+use crate::doctest::{Collector, GlobalTestOptions};
+use crate::html::escape::Escape;
+use crate::html::markdown;
+use crate::html::markdown::{
+    find_testable_code, ErrorCodes, HeadingOffset, IdMap, Markdown, MarkdownWithToc,
+};
+
+/// Separate any lines at the start of the file that begin with `# ` or `%`.
+fn extract_leading_metadata(s: &str) -> (Vec<&str>, &str) {
+    let mut metadata = Vec::new();
+    let mut count = 0;
+
+    for line in s.lines() {
+        if line.starts_with("# ") || line.starts_with('%') {
+            // trim the whitespace after the symbol
+            metadata.push(line[1..].trim_start());
+            count += line.len() + 1;
+        } else {
+            return (metadata, &s[count..]);
+        }
+    }
+
+    // if we're here, then all lines were metadata `# ` or `%` lines.
+    (metadata, "")
+}
+
+/// Render `input` (e.g., "foo.md") into an HTML file in `output`
+/// (e.g., output = "bar" => "bar/foo.html").
+pub(crate) fn render>(
+    input: P,
+    options: RenderOptions,
+    edition: Edition,
+) -> Result<(), String> {
+    if let Err(e) = create_dir_all(&options.output) {
+        return Err(format!("{}: {}", options.output.display(), e));
+    }
+
+    let input = input.as_ref();
+    let mut output = options.output;
+    output.push(input.file_name().unwrap());
+    output.set_extension("html");
+
+    let mut css = String::new();
+    for name in &options.markdown_css {
+        write!(css, r#""#)
+            .expect("Writing to a String can't fail");
+    }
+
+    let input_str = read_to_string(input).map_err(|err| format!("{}: {}", input.display(), err))?;
+    let playground_url = options.markdown_playground_url.or(options.playground_url);
+    let playground = playground_url.map(|url| markdown::Playground { crate_name: None, url });
+
+    let mut out = File::create(&output).map_err(|e| format!("{}: {}", output.display(), e))?;
+
+    let (metadata, text) = extract_leading_metadata(&input_str);
+    if metadata.is_empty() {
+        return Err("invalid markdown file: no initial lines starting with `# ` or `%`".to_owned());
+    }
+    let title = metadata[0];
+
+    let mut ids = IdMap::new();
+    let error_codes = ErrorCodes::from(options.unstable_features.is_nightly_build());
+    let text = if !options.markdown_no_toc {
+        MarkdownWithToc(text, &mut ids, error_codes, edition, &playground).into_string()
+    } else {
+        Markdown {
+            content: text,
+            links: &[],
+            ids: &mut ids,
+            error_codes,
+            edition,
+            playground: &playground,
+            heading_offset: HeadingOffset::H1,
+        }
+        .into_string()
+    };
+
+    let err = write!(
+        &mut out,
+        r#"
+
+
+    
+    
+    
+    {title}
+
+    {css}
+    {in_header}
+
+
+    
+
+    {before_content}
+    
    {title}
    
+    {text}
+    {after_content}
+
+"#,
+        title = Escape(title),
+        css = css,
+        in_header = options.external_html.in_header,
+        before_content = options.external_html.before_content,
+        text = text,
+        after_content = options.external_html.after_content,
+    );
+
+    match err {
+        Err(e) => Err(format!("cannot write to `{}`: {}", output.display(), e)),
+        Ok(_) => Ok(()),
+    }
+}
+
+/// Runs any tests/code examples in the markdown file `input`.
+pub(crate) fn test(options: Options) -> Result<(), String> {
+    let input_str = read_to_string(&options.input)
+        .map_err(|err| format!("{}: {}", options.input.display(), err))?;
+    let mut opts = GlobalTestOptions::default();
+    opts.no_crate_inject = true;
+    let mut collector = Collector::new(
+        Symbol::intern(&options.input.display().to_string()),
+        options.clone(),
+        true,
+        opts,
+        None,
+        Some(options.input),
+        options.enable_per_target_ignores,
+    );
+    collector.set_position(DUMMY_SP);
+    let codes = ErrorCodes::from(options.render_options.unstable_features.is_nightly_build());
+
+    find_testable_code(&input_str, &mut collector, codes, options.enable_per_target_ignores, None);
+
+    crate::doctest::run_tests(options.test_args, options.nocapture, collector.tests);
+    Ok(())
+}
diff --git a/src/librustdoc/passes/bare_urls.rs b/src/librustdoc/passes/bare_urls.rs
new file mode 100644
index 000000000..392e26ea6
--- /dev/null
+++ b/src/librustdoc/passes/bare_urls.rs
@@ -0,0 +1,112 @@
+//! Detects links that are not linkified, e.g., in Markdown such as `Go to https://example.com/.`
+//! Suggests wrapping the link with angle brackets: `Go to .` to linkify it.
+use super::Pass;
+use crate::clean::*;
+use crate::core::DocContext;
+use crate::html::markdown::main_body_opts;
+use crate::visit::DocVisitor;
+use core::ops::Range;
+use pulldown_cmark::{Event, Parser, Tag};
+use regex::Regex;
+use rustc_errors::Applicability;
+use std::mem;
+use std::sync::LazyLock;
+
+pub(crate) const CHECK_BARE_URLS: Pass = Pass {
+    name: "check-bare-urls",
+    run: check_bare_urls,
+    description: "detects URLs that are not hyperlinks",
+};
+
+static URL_REGEX: LazyLock = LazyLock::new(|| {
+    Regex::new(concat!(
+        r"https?://",                          // url scheme
+        r"([-a-zA-Z0-9@:%._\+~#=]{2,256}\.)+", // one or more subdomains
+        r"[a-zA-Z]{2,63}",                     // root domain
+        r"\b([-a-zA-Z0-9@:%_\+.~#?&/=]*)"      // optional query or url fragments
+    ))
+    .expect("failed to build regex")
+});
+
+struct BareUrlsLinter<'a, 'tcx> {
+    cx: &'a mut DocContext<'tcx>,
+}
+
+impl<'a, 'tcx> BareUrlsLinter<'a, 'tcx> {
+    fn find_raw_urls(
+        &self,
+        text: &str,
+        range: Range,
+        f: &impl Fn(&DocContext<'_>, &str, &str, Range),
+    ) {
+        trace!("looking for raw urls in {}", text);
+        // For now, we only check "full" URLs (meaning, starting with "http://" or "https://").
+        for match_ in URL_REGEX.find_iter(text) {
+            let url = match_.as_str();
+            let url_range = match_.range();
+            f(
+                self.cx,
+                "this URL is not a hyperlink",
+                url,
+                Range { start: range.start + url_range.start, end: range.start + url_range.end },
+            );
+        }
+    }
+}
+
+pub(crate) fn check_bare_urls(krate: Crate, cx: &mut DocContext<'_>) -> Crate {
+    BareUrlsLinter { cx }.visit_crate(&krate);
+    krate
+}
+
+impl<'a, 'tcx> DocVisitor for BareUrlsLinter<'a, 'tcx> {
+    fn visit_item(&mut self, item: &Item) {
+        let Some(hir_id) = DocContext::as_local_hir_id(self.cx.tcx, item.item_id)
+        else {
+            // If non-local, no need to check anything.
+            return;
+        };
+        let dox = item.attrs.collapsed_doc_value().unwrap_or_default();
+        if !dox.is_empty() {
+            let report_diag = |cx: &DocContext<'_>, msg: &str, url: &str, range: Range| {
+                let sp = super::source_span_for_markdown_range(cx.tcx, &dox, &range, &item.attrs)
+                    .unwrap_or_else(|| item.attr_span(cx.tcx));
+                cx.tcx.struct_span_lint_hir(crate::lint::BARE_URLS, hir_id, sp, |lint| {
+                    lint.build(msg)
+                        .note("bare URLs are not automatically turned into clickable links")
+                        .span_suggestion(
+                            sp,
+                            "use an automatic link instead",
+                            format!("<{}>", url),
+                            Applicability::MachineApplicable,
+                        )
+                        .emit();
+                });
+            };
+
+            let mut p = Parser::new_ext(&dox, main_body_opts()).into_offset_iter();
+
+            while let Some((event, range)) = p.next() {
+                match event {
+                    Event::Text(s) => self.find_raw_urls(&s, range, &report_diag),
+                    // We don't want to check the text inside code blocks or links.
+                    Event::Start(tag @ (Tag::CodeBlock(_) | Tag::Link(..))) => {
+                        while let Some((event, _)) = p.next() {
+                            match event {
+                                Event::End(end)
+                                    if mem::discriminant(&end) == mem::discriminant(&tag) =>
+                                {
+                                    break;
+                                }
+                                _ => {}
+                            }
+                        }
+                    }
+                    _ => {}
+                }
+            }
+        }
+
+        self.visit_item_recur(item)
+    }
+}
diff --git a/src/librustdoc/passes/calculate_doc_coverage.rs b/src/librustdoc/passes/calculate_doc_coverage.rs
new file mode 100644
index 000000000..4c6e3eb04
--- /dev/null
+++ b/src/librustdoc/passes/calculate_doc_coverage.rs
@@ -0,0 +1,276 @@
+//! Calculates information used for the --show-coverage flag.
+use crate::clean;
+use crate::core::DocContext;
+use crate::html::markdown::{find_testable_code, ErrorCodes};
+use crate::passes::check_doc_test_visibility::{should_have_doc_example, Tests};
+use crate::passes::Pass;
+use crate::visit::DocVisitor;
+use rustc_hir as hir;
+use rustc_lint::builtin::MISSING_DOCS;
+use rustc_middle::lint::LintLevelSource;
+use rustc_middle::ty::DefIdTree;
+use rustc_session::lint;
+use rustc_span::FileName;
+use serde::Serialize;
+
+use std::collections::BTreeMap;
+use std::ops;
+
+pub(crate) const CALCULATE_DOC_COVERAGE: Pass = Pass {
+    name: "calculate-doc-coverage",
+    run: calculate_doc_coverage,
+    description: "counts the number of items with and without documentation",
+};
+
+fn calculate_doc_coverage(krate: clean::Crate, ctx: &mut DocContext<'_>) -> clean::Crate {
+    let mut calc = CoverageCalculator { items: Default::default(), ctx };
+    calc.visit_crate(&krate);
+
+    calc.print_results();
+
+    krate
+}
+
+#[derive(Default, Copy, Clone, Serialize, Debug)]
+struct ItemCount {
+    total: u64,
+    with_docs: u64,
+    total_examples: u64,
+    with_examples: u64,
+}
+
+impl ItemCount {
+    fn count_item(
+        &mut self,
+        has_docs: bool,
+        has_doc_example: bool,
+        should_have_doc_examples: bool,
+        should_have_docs: bool,
+    ) {
+        if has_docs || should_have_docs {
+            self.total += 1;
+        }
+
+        if has_docs {
+            self.with_docs += 1;
+        }
+        if should_have_doc_examples || has_doc_example {
+            self.total_examples += 1;
+        }
+        if has_doc_example {
+            self.with_examples += 1;
+        }
+    }
+
+    fn percentage(&self) -> Option {
+        if self.total > 0 {
+            Some((self.with_docs as f64 * 100.0) / self.total as f64)
+        } else {
+            None
+        }
+    }
+
+    fn examples_percentage(&self) -> Option {
+        if self.total_examples > 0 {
+            Some((self.with_examples as f64 * 100.0) / self.total_examples as f64)
+        } else {
+            None
+        }
+    }
+}
+
+impl ops::Sub for ItemCount {
+    type Output = Self;
+
+    fn sub(self, rhs: Self) -> Self {
+        ItemCount {
+            total: self.total - rhs.total,
+            with_docs: self.with_docs - rhs.with_docs,
+            total_examples: self.total_examples - rhs.total_examples,
+            with_examples: self.with_examples - rhs.with_examples,
+        }
+    }
+}
+
+impl ops::AddAssign for ItemCount {
+    fn add_assign(&mut self, rhs: Self) {
+        self.total += rhs.total;
+        self.with_docs += rhs.with_docs;
+        self.total_examples += rhs.total_examples;
+        self.with_examples += rhs.with_examples;
+    }
+}
+
+struct CoverageCalculator<'a, 'b> {
+    items: BTreeMap,
+    ctx: &'a mut DocContext<'b>,
+}
+
+fn limit_filename_len(filename: String) -> String {
+    let nb_chars = filename.chars().count();
+    if nb_chars > 35 {
+        "...".to_string()
+            + &filename[filename.char_indices().nth(nb_chars - 32).map(|x| x.0).unwrap_or(0)..]
+    } else {
+        filename
+    }
+}
+
+impl<'a, 'b> CoverageCalculator<'a, 'b> {
+    fn to_json(&self) -> String {
+        serde_json::to_string(
+            &self
+                .items
+                .iter()
+                .map(|(k, v)| (k.prefer_local().to_string(), v))
+                .collect::>(),
+        )
+        .expect("failed to convert JSON data to string")
+    }
+
+    fn print_results(&self) {
+        let output_format = self.ctx.output_format;
+        if output_format.is_json() {
+            println!("{}", self.to_json());
+            return;
+        }
+        let mut total = ItemCount::default();
+
+        fn print_table_line() {
+            println!("+-{0:->35}-+-{0:->10}-+-{0:->10}-+-{0:->10}-+-{0:->10}-+", "");
+        }
+
+        fn print_table_record(
+            name: &str,
+            count: ItemCount,
+            percentage: f64,
+            examples_percentage: f64,
+        ) {
+            println!(
+                "| {:<35} | {:>10} | {:>9.1}% | {:>10} | {:>9.1}% |",
+                name, count.with_docs, percentage, count.with_examples, examples_percentage,
+            );
+        }
+
+        print_table_line();
+        println!(
+            "| {:<35} | {:>10} | {:>10} | {:>10} | {:>10} |",
+            "File", "Documented", "Percentage", "Examples", "Percentage",
+        );
+        print_table_line();
+
+        for (file, &count) in &self.items {
+            if let Some(percentage) = count.percentage() {
+                print_table_record(
+                    &limit_filename_len(file.prefer_local().to_string_lossy().into()),
+                    count,
+                    percentage,
+                    count.examples_percentage().unwrap_or(0.),
+                );
+
+                total += count;
+            }
+        }
+
+        print_table_line();
+        print_table_record(
+            "Total",
+            total,
+            total.percentage().unwrap_or(0.0),
+            total.examples_percentage().unwrap_or(0.0),
+        );
+        print_table_line();
+    }
+}
+
+impl<'a, 'b> DocVisitor for CoverageCalculator<'a, 'b> {
+    fn visit_item(&mut self, i: &clean::Item) {
+        if !i.item_id.is_local() {
+            // non-local items are skipped because they can be out of the users control,
+            // especially in the case of trait impls, which rustdoc eagerly inlines
+            return;
+        }
+
+        match *i.kind {
+            clean::StrippedItem(..) => {
+                // don't count items in stripped modules
+                return;
+            }
+            // docs on `use` and `extern crate` statements are not displayed, so they're not
+            // worth counting
+            clean::ImportItem(..) | clean::ExternCrateItem { .. } => {}
+            // Don't count trait impls, the missing-docs lint doesn't so we shouldn't either.
+            // Inherent impls *can* be documented, and those docs show up, but in most cases it
+            // doesn't make sense, as all methods on a type are in one single impl block
+            clean::ImplItem(_) => {}
+            _ => {
+                let has_docs = !i.attrs.doc_strings.is_empty();
+                let mut tests = Tests { found_tests: 0 };
+
+                find_testable_code(
+                    &i.attrs.collapsed_doc_value().unwrap_or_default(),
+                    &mut tests,
+                    ErrorCodes::No,
+                    false,
+                    None,
+                );
+
+                let filename = i.span(self.ctx.tcx).filename(self.ctx.sess());
+                let has_doc_example = tests.found_tests != 0;
+                // The `expect_def_id()` should be okay because `local_def_id_to_hir_id`
+                // would presumably panic if a fake `DefIndex` were passed.
+                let hir_id = self
+                    .ctx
+                    .tcx
+                    .hir()
+                    .local_def_id_to_hir_id(i.item_id.expect_def_id().expect_local());
+                let (level, source) = self.ctx.tcx.lint_level_at_node(MISSING_DOCS, hir_id);
+
+                // In case we have:
+                //
+                // ```
+                // enum Foo { Bar(u32) }
+                // // or:
+                // struct Bar(u32);
+                // ```
+                //
+                // there is no need to require documentation on the fields of tuple variants and
+                // tuple structs.
+                let should_be_ignored = i
+                    .item_id
+                    .as_def_id()
+                    .and_then(|def_id| self.ctx.tcx.opt_parent(def_id))
+                    .and_then(|def_id| self.ctx.tcx.hir().get_if_local(def_id))
+                    .map(|node| {
+                        matches!(
+                            node,
+                            hir::Node::Variant(hir::Variant {
+                                data: hir::VariantData::Tuple(_, _),
+                                ..
+                            }) | hir::Node::Item(hir::Item {
+                                kind: hir::ItemKind::Struct(hir::VariantData::Tuple(_, _), _),
+                                ..
+                            })
+                        )
+                    })
+                    .unwrap_or(false);
+
+                // `missing_docs` is allow-by-default, so don't treat this as ignoring the item
+                // unless the user had an explicit `allow`.
+                //
+                let should_have_docs = !should_be_ignored
+                    && (level != lint::Level::Allow || matches!(source, LintLevelSource::Default));
+
+                debug!("counting {:?} {:?} in {:?}", i.type_(), i.name, filename);
+                self.items.entry(filename).or_default().count_item(
+                    has_docs,
+                    has_doc_example,
+                    should_have_doc_example(self.ctx, i),
+                    should_have_docs,
+                );
+            }
+        }
+
+        self.visit_item_recur(i)
+    }
+}
diff --git a/src/librustdoc/passes/check_code_block_syntax.rs b/src/librustdoc/passes/check_code_block_syntax.rs
new file mode 100644
index 000000000..0172ef570
--- /dev/null
+++ b/src/librustdoc/passes/check_code_block_syntax.rs
@@ -0,0 +1,205 @@
+//! Validates syntax inside Rust code blocks (\`\`\`rust).
+use rustc_data_structures::sync::{Lock, Lrc};
+use rustc_errors::{
+    emitter::Emitter, Applicability, Diagnostic, Handler, LazyFallbackBundle, LintDiagnosticBuilder,
+};
+use rustc_parse::parse_stream_from_source_str;
+use rustc_session::parse::ParseSess;
+use rustc_span::hygiene::{AstPass, ExpnData, ExpnKind, LocalExpnId};
+use rustc_span::source_map::{FilePathMapping, SourceMap};
+use rustc_span::{FileName, InnerSpan, DUMMY_SP};
+
+use crate::clean;
+use crate::core::DocContext;
+use crate::html::markdown::{self, RustCodeBlock};
+use crate::passes::Pass;
+use crate::visit::DocVisitor;
+
+pub(crate) const CHECK_CODE_BLOCK_SYNTAX: Pass = Pass {
+    name: "check-code-block-syntax",
+    run: check_code_block_syntax,
+    description: "validates syntax inside Rust code blocks",
+};
+
+pub(crate) fn check_code_block_syntax(
+    krate: clean::Crate,
+    cx: &mut DocContext<'_>,
+) -> clean::Crate {
+    SyntaxChecker { cx }.visit_crate(&krate);
+    krate
+}
+
+struct SyntaxChecker<'a, 'tcx> {
+    cx: &'a DocContext<'tcx>,
+}
+
+impl<'a, 'tcx> SyntaxChecker<'a, 'tcx> {
+    fn check_rust_syntax(&self, item: &clean::Item, dox: &str, code_block: RustCodeBlock) {
+        let buffer = Lrc::new(Lock::new(Buffer::default()));
+        let fallback_bundle =
+            rustc_errors::fallback_fluent_bundle(rustc_errors::DEFAULT_LOCALE_RESOURCES, false);
+        let emitter = BufferEmitter { buffer: Lrc::clone(&buffer), fallback_bundle };
+
+        let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
+        let handler = Handler::with_emitter(false, None, Box::new(emitter));
+        let source = dox[code_block.code].to_owned();
+        let sess = ParseSess::with_span_handler(handler, sm);
+
+        let edition = code_block.lang_string.edition.unwrap_or_else(|| self.cx.tcx.sess.edition());
+        let expn_data = ExpnData::default(
+            ExpnKind::AstPass(AstPass::TestHarness),
+            DUMMY_SP,
+            edition,
+            None,
+            None,
+        );
+        let expn_id =
+            self.cx.tcx.with_stable_hashing_context(|hcx| LocalExpnId::fresh(expn_data, hcx));
+        let span = DUMMY_SP.fresh_expansion(expn_id);
+
+        let is_empty = rustc_driver::catch_fatal_errors(|| {
+            parse_stream_from_source_str(
+                FileName::Custom(String::from("doctest")),
+                source,
+                &sess,
+                Some(span),
+            )
+            .is_empty()
+        })
+        .unwrap_or(false);
+        let buffer = buffer.borrow();
+
+        if !buffer.has_errors && !is_empty {
+            // No errors in a non-empty program.
+            return;
+        }
+
+        let Some(local_id) = item.item_id.as_def_id().and_then(|x| x.as_local())
+        else {
+            // We don't need to check the syntax for other crates so returning
+            // without doing anything should not be a problem.
+            return;
+        };
+
+        let hir_id = self.cx.tcx.hir().local_def_id_to_hir_id(local_id);
+        let empty_block = code_block.lang_string == Default::default() && code_block.is_fenced;
+        let is_ignore = code_block.lang_string.ignore != markdown::Ignore::None;
+
+        // The span and whether it is precise or not.
+        let (sp, precise_span) = match super::source_span_for_markdown_range(
+            self.cx.tcx,
+            dox,
+            &code_block.range,
+            &item.attrs,
+        ) {
+            Some(sp) => (sp, true),
+            None => (item.attr_span(self.cx.tcx), false),
+        };
+
+        // lambda that will use the lint to start a new diagnostic and add
+        // a suggestion to it when needed.
+        let diag_builder = |lint: LintDiagnosticBuilder<'_, ()>| {
+            let explanation = if is_ignore {
+                "`ignore` code blocks require valid Rust code for syntax highlighting; \
+                    mark blocks that do not contain Rust code as text"
+            } else {
+                "mark blocks that do not contain Rust code as text"
+            };
+            let msg = if buffer.has_errors {
+                "could not parse code block as Rust code"
+            } else {
+                "Rust code block is empty"
+            };
+            let mut diag = lint.build(msg);
+
+            if precise_span {
+                if is_ignore {
+                    // giving an accurate suggestion is hard because `ignore` might not have come first in the list.
+                    // just give a `help` instead.
+                    diag.span_help(
+                        sp.from_inner(InnerSpan::new(0, 3)),
+                        &format!("{}: ```text", explanation),
+                    );
+                } else if empty_block {
+                    diag.span_suggestion(
+                        sp.from_inner(InnerSpan::new(0, 3)).shrink_to_hi(),
+                        explanation,
+                        "text",
+                        Applicability::MachineApplicable,
+                    );
+                }
+            } else if empty_block || is_ignore {
+                diag.help(&format!("{}: ```text", explanation));
+            }
+
+            // FIXME(#67563): Provide more context for these errors by displaying the spans inline.
+            for message in buffer.messages.iter() {
+                diag.note(message);
+            }
+
+            diag.emit();
+        };
+
+        // Finally build and emit the completed diagnostic.
+        // All points of divergence have been handled earlier so this can be
+        // done the same way whether the span is precise or not.
+        self.cx.tcx.struct_span_lint_hir(
+            crate::lint::INVALID_RUST_CODEBLOCKS,
+            hir_id,
+            sp,
+            diag_builder,
+        );
+    }
+}
+
+impl<'a, 'tcx> DocVisitor for SyntaxChecker<'a, 'tcx> {
+    fn visit_item(&mut self, item: &clean::Item) {
+        if let Some(dox) = &item.attrs.collapsed_doc_value() {
+            let sp = item.attr_span(self.cx.tcx);
+            let extra = crate::html::markdown::ExtraInfo::new_did(
+                self.cx.tcx,
+                item.item_id.expect_def_id(),
+                sp,
+            );
+            for code_block in markdown::rust_code_blocks(dox, &extra) {
+                self.check_rust_syntax(item, dox, code_block);
+            }
+        }
+
+        self.visit_item_recur(item)
+    }
+}
+
+#[derive(Default)]
+struct Buffer {
+    messages: Vec,
+    has_errors: bool,
+}
+
+struct BufferEmitter {
+    buffer: Lrc>,
+    fallback_bundle: LazyFallbackBundle,
+}
+
+impl Emitter for BufferEmitter {
+    fn emit_diagnostic(&mut self, diag: &Diagnostic) {
+        let mut buffer = self.buffer.borrow_mut();
+        // FIXME(davidtwco): need to support translation here eventually
+        buffer.messages.push(format!("error from rustc: {}", diag.message[0].0.expect_str()));
+        if diag.is_error() {
+            buffer.has_errors = true;
+        }
+    }
+
+    fn source_map(&self) -> Option<&Lrc> {
+        None
+    }
+
+    fn fluent_bundle(&self) -> Option<&Lrc> {
+        None
+    }
+
+    fn fallback_fluent_bundle(&self) -> &rustc_errors::FluentBundle {
+        &**self.fallback_bundle
+    }
+}
diff --git a/src/librustdoc/passes/check_doc_test_visibility.rs b/src/librustdoc/passes/check_doc_test_visibility.rs
new file mode 100644
index 000000000..e86f90833
--- /dev/null
+++ b/src/librustdoc/passes/check_doc_test_visibility.rs
@@ -0,0 +1,145 @@
+//! Looks for items missing (or incorrectly having) doctests.
+//!
+//! This pass is overloaded and runs two different lints.
+//!
+//! - MISSING_DOC_CODE_EXAMPLES: this lint is **UNSTABLE** and looks for public items missing doctests.
+//! - PRIVATE_DOC_TESTS: this lint is **STABLE** and looks for private items with doctests.
+
+use super::Pass;
+use crate::clean;
+use crate::clean::*;
+use crate::core::DocContext;
+use crate::html::markdown::{find_testable_code, ErrorCodes, Ignore, LangString};
+use crate::visit::DocVisitor;
+use crate::visit_ast::inherits_doc_hidden;
+use rustc_hir as hir;
+use rustc_middle::lint::LintLevelSource;
+use rustc_session::lint;
+use rustc_span::symbol::sym;
+
+pub(crate) const CHECK_DOC_TEST_VISIBILITY: Pass = Pass {
+    name: "check_doc_test_visibility",
+    run: check_doc_test_visibility,
+    description: "run various visibility-related lints on doctests",
+};
+
+struct DocTestVisibilityLinter<'a, 'tcx> {
+    cx: &'a mut DocContext<'tcx>,
+}
+
+pub(crate) fn check_doc_test_visibility(krate: Crate, cx: &mut DocContext<'_>) -> Crate {
+    let mut coll = DocTestVisibilityLinter { cx };
+    coll.visit_crate(&krate);
+    krate
+}
+
+impl<'a, 'tcx> DocVisitor for DocTestVisibilityLinter<'a, 'tcx> {
+    fn visit_item(&mut self, item: &Item) {
+        let dox = item.attrs.collapsed_doc_value().unwrap_or_default();
+
+        look_for_tests(self.cx, &dox, item);
+
+        self.visit_item_recur(item)
+    }
+}
+
+pub(crate) struct Tests {
+    pub(crate) found_tests: usize,
+}
+
+impl crate::doctest::Tester for Tests {
+    fn add_test(&mut self, _: String, config: LangString, _: usize) {
+        if config.rust && config.ignore == Ignore::None {
+            self.found_tests += 1;
+        }
+    }
+}
+
+pub(crate) fn should_have_doc_example(cx: &DocContext<'_>, item: &clean::Item) -> bool {
+    if !cx.cache.access_levels.is_public(item.item_id.expect_def_id())
+        || matches!(
+            *item.kind,
+            clean::StructFieldItem(_)
+                | clean::VariantItem(_)
+                | clean::AssocConstItem(..)
+                | clean::AssocTypeItem(..)
+                | clean::TypedefItem(_)
+                | clean::StaticItem(_)
+                | clean::ConstantItem(_)
+                | clean::ExternCrateItem { .. }
+                | clean::ImportItem(_)
+                | clean::PrimitiveItem(_)
+                | clean::KeywordItem
+                // check for trait impl
+                | clean::ImplItem(box clean::Impl { trait_: Some(_), .. })
+        )
+    {
+        return false;
+    }
+
+    // The `expect_def_id()` should be okay because `local_def_id_to_hir_id`
+    // would presumably panic if a fake `DefIndex` were passed.
+    let hir_id = cx.tcx.hir().local_def_id_to_hir_id(item.item_id.expect_def_id().expect_local());
+
+    // check if parent is trait impl
+    if let Some(parent_hir_id) = cx.tcx.hir().find_parent_node(hir_id) {
+        if let Some(parent_node) = cx.tcx.hir().find(parent_hir_id) {
+            if matches!(
+                parent_node,
+                hir::Node::Item(hir::Item {
+                    kind: hir::ItemKind::Impl(hir::Impl { of_trait: Some(_), .. }),
+                    ..
+                })
+            ) {
+                return false;
+            }
+        }
+    }
+
+    if cx.tcx.hir().attrs(hir_id).lists(sym::doc).has_word(sym::hidden)
+        || inherits_doc_hidden(cx.tcx, hir_id)
+        || cx.tcx.hir().span(hir_id).in_derive_expansion()
+    {
+        return false;
+    }
+    let (level, source) = cx.tcx.lint_level_at_node(crate::lint::MISSING_DOC_CODE_EXAMPLES, hir_id);
+    level != lint::Level::Allow || matches!(source, LintLevelSource::Default)
+}
+
+pub(crate) fn look_for_tests<'tcx>(cx: &DocContext<'tcx>, dox: &str, item: &Item) {
+    let Some(hir_id) = DocContext::as_local_hir_id(cx.tcx, item.item_id)
+    else {
+        // If non-local, no need to check anything.
+        return;
+    };
+
+    let mut tests = Tests { found_tests: 0 };
+
+    find_testable_code(dox, &mut tests, ErrorCodes::No, false, None);
+
+    if tests.found_tests == 0 && cx.tcx.sess.is_nightly_build() {
+        if should_have_doc_example(cx, item) {
+            debug!("reporting error for {:?} (hir_id={:?})", item, hir_id);
+            let sp = item.attr_span(cx.tcx);
+            cx.tcx.struct_span_lint_hir(
+                crate::lint::MISSING_DOC_CODE_EXAMPLES,
+                hir_id,
+                sp,
+                |lint| {
+                    lint.build("missing code example in this documentation").emit();
+                },
+            );
+        }
+    } else if tests.found_tests > 0
+        && !cx.cache.access_levels.is_exported(item.item_id.expect_def_id())
+    {
+        cx.tcx.struct_span_lint_hir(
+            crate::lint::PRIVATE_DOC_TESTS,
+            hir_id,
+            item.attr_span(cx.tcx),
+            |lint| {
+                lint.build("documentation test in private item").emit();
+            },
+        );
+    }
+}
diff --git a/src/librustdoc/passes/collect_intra_doc_links.rs b/src/librustdoc/passes/collect_intra_doc_links.rs
new file mode 100644
index 000000000..7d7a63c53
--- /dev/null
+++ b/src/librustdoc/passes/collect_intra_doc_links.rs
@@ -0,0 +1,2161 @@
+//! This module implements [RFC 1946]: Intra-rustdoc-links
+//!
+//! [RFC 1946]: https://github.com/rust-lang/rfcs/blob/master/text/1946-intra-rustdoc-links.md
+
+use pulldown_cmark::LinkType;
+use rustc_ast::util::comments::may_have_doc_links;
+use rustc_data_structures::{
+    fx::{FxHashMap, FxHashSet},
+    intern::Interned,
+};
+use rustc_errors::{Applicability, Diagnostic};
+use rustc_hir::def::Namespace::*;
+use rustc_hir::def::{DefKind, Namespace, PerNS};
+use rustc_hir::def_id::{DefId, CRATE_DEF_ID};
+use rustc_hir::Mutability;
+use rustc_middle::ty::{DefIdTree, Ty, TyCtxt};
+use rustc_middle::{bug, ty};
+use rustc_resolve::ParentScope;
+use rustc_session::lint::Lint;
+use rustc_span::hygiene::MacroKind;
+use rustc_span::symbol::{sym, Ident, Symbol};
+use rustc_span::BytePos;
+use smallvec::{smallvec, SmallVec};
+
+use std::borrow::Cow;
+use std::mem;
+use std::ops::Range;
+
+use crate::clean::{self, utils::find_nearest_parent_module};
+use crate::clean::{Crate, Item, ItemId, ItemLink, PrimitiveType};
+use crate::core::DocContext;
+use crate::html::markdown::{markdown_links, MarkdownLink};
+use crate::lint::{BROKEN_INTRA_DOC_LINKS, PRIVATE_INTRA_DOC_LINKS};
+use crate::passes::Pass;
+use crate::visit::DocVisitor;
+
+mod early;
+pub(crate) use early::early_resolve_intra_doc_links;
+
+pub(crate) const COLLECT_INTRA_DOC_LINKS: Pass = Pass {
+    name: "collect-intra-doc-links",
+    run: collect_intra_doc_links,
+    description: "resolves intra-doc links",
+};
+
+fn collect_intra_doc_links(krate: Crate, cx: &mut DocContext<'_>) -> Crate {
+    let mut collector =
+        LinkCollector { cx, mod_ids: Vec::new(), visited_links: FxHashMap::default() };
+    collector.visit_crate(&krate);
+    krate
+}
+
+#[derive(Copy, Clone, Debug, Hash)]
+enum Res {
+    Def(DefKind, DefId),
+    Primitive(PrimitiveType),
+}
+
+type ResolveRes = rustc_hir::def::Res;
+
+impl Res {
+    fn descr(self) -> &'static str {
+        match self {
+            Res::Def(kind, id) => ResolveRes::Def(kind, id).descr(),
+            Res::Primitive(_) => "builtin type",
+        }
+    }
+
+    fn article(self) -> &'static str {
+        match self {
+            Res::Def(kind, id) => ResolveRes::Def(kind, id).article(),
+            Res::Primitive(_) => "a",
+        }
+    }
+
+    fn name(self, tcx: TyCtxt<'_>) -> Symbol {
+        match self {
+            Res::Def(_, id) => tcx.item_name(id),
+            Res::Primitive(prim) => prim.as_sym(),
+        }
+    }
+
+    fn def_id(self, tcx: TyCtxt<'_>) -> DefId {
+        match self {
+            Res::Def(_, id) => id,
+            Res::Primitive(prim) => *PrimitiveType::primitive_locations(tcx).get(&prim).unwrap(),
+        }
+    }
+
+    fn from_def_id(tcx: TyCtxt<'_>, def_id: DefId) -> Res {
+        Res::Def(tcx.def_kind(def_id), def_id)
+    }
+
+    /// Used for error reporting.
+    fn disambiguator_suggestion(self) -> Suggestion {
+        let kind = match self {
+            Res::Primitive(_) => return Suggestion::Prefix("prim"),
+            Res::Def(kind, _) => kind,
+        };
+        if kind == DefKind::Macro(MacroKind::Bang) {
+            return Suggestion::Macro;
+        } else if kind == DefKind::Fn || kind == DefKind::AssocFn {
+            return Suggestion::Function;
+        } else if kind == DefKind::Field {
+            return Suggestion::RemoveDisambiguator;
+        }
+
+        let prefix = match kind {
+            DefKind::Struct => "struct",
+            DefKind::Enum => "enum",
+            DefKind::Trait => "trait",
+            DefKind::Union => "union",
+            DefKind::Mod => "mod",
+            DefKind::Const | DefKind::ConstParam | DefKind::AssocConst | DefKind::AnonConst => {
+                "const"
+            }
+            DefKind::Static(_) => "static",
+            DefKind::Macro(MacroKind::Derive) => "derive",
+            // Now handle things that don't have a specific disambiguator
+            _ => match kind
+                .ns()
+                .expect("tried to calculate a disambiguator for a def without a namespace?")
+            {
+                Namespace::TypeNS => "type",
+                Namespace::ValueNS => "value",
+                Namespace::MacroNS => "macro",
+            },
+        };
+
+        Suggestion::Prefix(prefix)
+    }
+}
+
+impl TryFrom for Res {
+    type Error = ();
+
+    fn try_from(res: ResolveRes) -> Result {
+        use rustc_hir::def::Res::*;
+        match res {
+            Def(kind, id) => Ok(Res::Def(kind, id)),
+            PrimTy(prim) => Ok(Res::Primitive(PrimitiveType::from_hir(prim))),
+            // e.g. `#[derive]`
+            NonMacroAttr(..) | Err => Result::Err(()),
+            other => bug!("unrecognized res {:?}", other),
+        }
+    }
+}
+
+/// The link failed to resolve. [`resolution_failure`] should look to see if there's
+/// a more helpful error that can be given.
+#[derive(Debug)]
+struct UnresolvedPath<'a> {
+    /// Item on which the link is resolved, used for resolving `Self`.
+    item_id: ItemId,
+    /// The scope the link was resolved in.
+    module_id: DefId,
+    /// If part of the link resolved, this has the `Res`.
+    ///
+    /// In `[std::io::Error::x]`, `std::io::Error` would be a partial resolution.
+    partial_res: Option,
+    /// The remaining unresolved path segments.
+    ///
+    /// In `[std::io::Error::x]`, `x` would be unresolved.
+    unresolved: Cow<'a, str>,
+}
+
+#[derive(Debug)]
+enum ResolutionFailure<'a> {
+    /// This resolved, but with the wrong namespace.
+    WrongNamespace {
+        /// What the link resolved to.
+        res: Res,
+        /// The expected namespace for the resolution, determined from the link's disambiguator.
+        ///
+        /// E.g., for `[fn@Result]` this is [`Namespace::ValueNS`],
+        /// even though `Result`'s actual namespace is [`Namespace::TypeNS`].
+        expected_ns: Namespace,
+    },
+    NotResolved(UnresolvedPath<'a>),
+}
+
+#[derive(Clone, Copy, Debug)]
+enum MalformedGenerics {
+    /// This link has unbalanced angle brackets.
+    ///
+    /// For example, `Vec>`.
+    UnbalancedAngleBrackets,
+    /// The generics are not attached to a type.
+    ///
+    /// For example, `` should trigger this.
+    ///
+    /// This is detected by checking if the path is empty after the generics are stripped.
+    MissingType,
+    /// The link uses fully-qualified syntax, which is currently unsupported.
+    ///
+    /// For example, `::into_iter` should trigger this.
+    ///
+    /// This is detected by checking if ` as ` (the keyword `as` with spaces around it) is inside
+    /// angle brackets.
+    HasFullyQualifiedSyntax,
+    /// The link has an invalid path separator.
+    ///
+    /// For example, `Vec::new()` should trigger this. Note that `Vec:new()` will **not**
+    /// trigger this because it has no generics and thus [`strip_generics_from_path`] will not be
+    /// called.
+    ///
+    /// Note that this will also **not** be triggered if the invalid path separator is inside angle
+    /// brackets because rustdoc mostly ignores what's inside angle brackets (except for
+    /// [`HasFullyQualifiedSyntax`](MalformedGenerics::HasFullyQualifiedSyntax)).
+    ///
+    /// This is detected by checking if there is a colon followed by a non-colon in the link.
+    InvalidPathSeparator,
+    /// The link has too many angle brackets.
+    ///
+    /// For example, `Vec<>` should trigger this.
+    TooManyAngleBrackets,
+    /// The link has empty angle brackets.
+    ///
+    /// For example, `Vec<>` should trigger this.
+    EmptyAngleBrackets,
+}
+
+#[derive(Clone, Debug, Hash, PartialEq, Eq)]
+pub(crate) enum UrlFragment {
+    Item(DefId),
+    UserWritten(String),
+}
+
+impl UrlFragment {
+    /// Render the fragment, including the leading `#`.
+    pub(crate) fn render(&self, s: &mut String, tcx: TyCtxt<'_>) {
+        s.push('#');
+        match self {
+            &UrlFragment::Item(def_id) => {
+                let kind = match tcx.def_kind(def_id) {
+                    DefKind::AssocFn => {
+                        if tcx.impl_defaultness(def_id).has_value() {
+                            "method."
+                        } else {
+                            "tymethod."
+                        }
+                    }
+                    DefKind::AssocConst => "associatedconstant.",
+                    DefKind::AssocTy => "associatedtype.",
+                    DefKind::Variant => "variant.",
+                    DefKind::Field => {
+                        let parent_id = tcx.parent(def_id);
+                        if tcx.def_kind(parent_id) == DefKind::Variant {
+                            s.push_str("variant.");
+                            s.push_str(tcx.item_name(parent_id).as_str());
+                            ".field."
+                        } else {
+                            "structfield."
+                        }
+                    }
+                    kind => bug!("unexpected associated item kind: {:?}", kind),
+                };
+                s.push_str(kind);
+                s.push_str(tcx.item_name(def_id).as_str());
+            }
+            UrlFragment::UserWritten(raw) => s.push_str(&raw),
+        }
+    }
+}
+
+#[derive(Clone, Debug, Hash, PartialEq, Eq)]
+struct ResolutionInfo {
+    item_id: ItemId,
+    module_id: DefId,
+    dis: Option,
+    path_str: String,
+    extra_fragment: Option,
+}
+
+#[derive(Clone)]
+struct DiagnosticInfo<'a> {
+    item: &'a Item,
+    dox: &'a str,
+    ori_link: &'a str,
+    link_range: Range,
+}
+
+struct LinkCollector<'a, 'tcx> {
+    cx: &'a mut DocContext<'tcx>,
+    /// A stack of modules used to decide what scope to resolve in.
+    ///
+    /// The last module will be used if the parent scope of the current item is
+    /// unknown.
+    mod_ids: Vec,
+    /// Cache the resolved links so we can avoid resolving (and emitting errors for) the same link.
+    /// The link will be `None` if it could not be resolved (i.e. the error was cached).
+    visited_links: FxHashMap)>>,
+}
+
+impl<'a, 'tcx> LinkCollector<'a, 'tcx> {
+    /// Given a full link, parse it as an [enum struct variant].
+    ///
+    /// In particular, this will return an error whenever there aren't three
+    /// full path segments left in the link.
+    ///
+    /// [enum struct variant]: rustc_hir::VariantData::Struct
+    fn variant_field<'path>(
+        &self,
+        path_str: &'path str,
+        item_id: ItemId,
+        module_id: DefId,
+    ) -> Result<(Res, DefId), UnresolvedPath<'path>> {
+        let tcx = self.cx.tcx;
+        let no_res = || UnresolvedPath {
+            item_id,
+            module_id,
+            partial_res: None,
+            unresolved: path_str.into(),
+        };
+
+        debug!("looking for enum variant {}", path_str);
+        let mut split = path_str.rsplitn(3, "::");
+        let variant_field_name = split
+            .next()
+            .map(|f| Symbol::intern(f))
+            .expect("fold_item should ensure link is non-empty");
+        let variant_name =
+            // we're not sure this is a variant at all, so use the full string
+            // If there's no second component, the link looks like `[path]`.
+            // So there's no partial res and we should say the whole link failed to resolve.
+            split.next().map(|f|  Symbol::intern(f)).ok_or_else(no_res)?;
+        let path = split
+            .next()
+            .map(|f| f.to_owned())
+            // If there's no third component, we saw `[a::b]` before and it failed to resolve.
+            // So there's no partial res.
+            .ok_or_else(no_res)?;
+        let ty_res = self.resolve_path(&path, TypeNS, item_id, module_id).ok_or_else(no_res)?;
+
+        match ty_res {
+            Res::Def(DefKind::Enum, did) => match tcx.type_of(did).kind() {
+                ty::Adt(def, _) if def.is_enum() => {
+                    if let Some(field) = def.all_fields().find(|f| f.name == variant_field_name) {
+                        Ok((ty_res, field.did))
+                    } else {
+                        Err(UnresolvedPath {
+                            item_id,
+                            module_id,
+                            partial_res: Some(Res::Def(DefKind::Enum, def.did())),
+                            unresolved: variant_field_name.to_string().into(),
+                        })
+                    }
+                }
+                _ => unreachable!(),
+            },
+            _ => Err(UnresolvedPath {
+                item_id,
+                module_id,
+                partial_res: Some(ty_res),
+                unresolved: variant_name.to_string().into(),
+            }),
+        }
+    }
+
+    /// Given a primitive type, try to resolve an associated item.
+    fn resolve_primitive_associated_item(
+        &self,
+        prim_ty: PrimitiveType,
+        ns: Namespace,
+        item_name: Symbol,
+    ) -> Option<(Res, DefId)> {
+        let tcx = self.cx.tcx;
+
+        prim_ty.impls(tcx).find_map(|impl_| {
+            tcx.associated_items(impl_)
+                .find_by_name_and_namespace(tcx, Ident::with_dummy_span(item_name), ns, impl_)
+                .map(|item| (Res::Primitive(prim_ty), item.def_id))
+        })
+    }
+
+    fn resolve_self_ty(&self, path_str: &str, ns: Namespace, item_id: ItemId) -> Option {
+        if ns != TypeNS || path_str != "Self" {
+            return None;
+        }
+
+        let tcx = self.cx.tcx;
+        item_id
+            .as_def_id()
+            .map(|def_id| match tcx.def_kind(def_id) {
+                def_kind @ (DefKind::AssocFn
+                | DefKind::AssocConst
+                | DefKind::AssocTy
+                | DefKind::Variant
+                | DefKind::Field) => {
+                    let parent_def_id = tcx.parent(def_id);
+                    if def_kind == DefKind::Field && tcx.def_kind(parent_def_id) == DefKind::Variant
+                    {
+                        tcx.parent(parent_def_id)
+                    } else {
+                        parent_def_id
+                    }
+                }
+                _ => def_id,
+            })
+            .and_then(|self_id| match tcx.def_kind(self_id) {
+                DefKind::Impl => self.def_id_to_res(self_id),
+                def_kind => Some(Res::Def(def_kind, self_id)),
+            })
+    }
+
+    /// Convenience wrapper around `resolve_rustdoc_path`.
+    ///
+    /// This also handles resolving `true` and `false` as booleans.
+    /// NOTE: `resolve_rustdoc_path` knows only about paths, not about types.
+    /// Associated items will never be resolved by this function.
+    fn resolve_path(
+        &self,
+        path_str: &str,
+        ns: Namespace,
+        item_id: ItemId,
+        module_id: DefId,
+    ) -> Option {
+        if let res @ Some(..) = self.resolve_self_ty(path_str, ns, item_id) {
+            return res;
+        }
+
+        // Resolver doesn't know about true, false, and types that aren't paths (e.g. `()`).
+        let result = self
+            .cx
+            .resolver_caches
+            .doc_link_resolutions
+            .get(&(Symbol::intern(path_str), ns, module_id))
+            .copied()
+            .unwrap_or_else(|| {
+                self.cx.enter_resolver(|resolver| {
+                    let parent_scope =
+                        ParentScope::module(resolver.expect_module(module_id), resolver);
+                    resolver.resolve_rustdoc_path(path_str, ns, parent_scope)
+                })
+            })
+            .and_then(|res| res.try_into().ok())
+            .or_else(|| resolve_primitive(path_str, ns));
+        debug!("{} resolved to {:?} in namespace {:?}", path_str, result, ns);
+        result
+    }
+
+    /// Resolves a string as a path within a particular namespace. Returns an
+    /// optional URL fragment in the case of variants and methods.
+    fn resolve<'path>(
+        &mut self,
+        path_str: &'path str,
+        ns: Namespace,
+        item_id: ItemId,
+        module_id: DefId,
+    ) -> Result<(Res, Option), UnresolvedPath<'path>> {
+        if let Some(res) = self.resolve_path(path_str, ns, item_id, module_id) {
+            return Ok(match res {
+                Res::Def(
+                    DefKind::AssocFn | DefKind::AssocConst | DefKind::AssocTy | DefKind::Variant,
+                    def_id,
+                ) => (Res::from_def_id(self.cx.tcx, self.cx.tcx.parent(def_id)), Some(def_id)),
+                _ => (res, None),
+            });
+        } else if ns == MacroNS {
+            return Err(UnresolvedPath {
+                item_id,
+                module_id,
+                partial_res: None,
+                unresolved: path_str.into(),
+            });
+        }
+
+        // Try looking for methods and associated items.
+        let mut split = path_str.rsplitn(2, "::");
+        // NB: `split`'s first element is always defined, even if the delimiter was not present.
+        // NB: `item_str` could be empty when resolving in the root namespace (e.g. `::std`).
+        let item_str = split.next().unwrap();
+        let item_name = Symbol::intern(item_str);
+        let path_root = split
+            .next()
+            .map(|f| f.to_owned())
+            // If there's no `::`, it's not an associated item.
+            // So we can be sure that `rustc_resolve` was accurate when it said it wasn't resolved.
+            .ok_or_else(|| {
+                debug!("found no `::`, assumming {} was correctly not in scope", item_name);
+                UnresolvedPath {
+                    item_id,
+                    module_id,
+                    partial_res: None,
+                    unresolved: item_str.into(),
+                }
+            })?;
+
+        // FIXME(#83862): this arbitrarily gives precedence to primitives over modules to support
+        // links to primitives when `#[doc(primitive)]` is present. It should give an ambiguity
+        // error instead and special case *only* modules with `#[doc(primitive)]`, not all
+        // primitives.
+        resolve_primitive(&path_root, TypeNS)
+            .or_else(|| self.resolve_path(&path_root, TypeNS, item_id, module_id))
+            .and_then(|ty_res| {
+                self.resolve_associated_item(ty_res, item_name, ns, module_id).map(Ok)
+            })
+            .unwrap_or_else(|| {
+                if ns == Namespace::ValueNS {
+                    self.variant_field(path_str, item_id, module_id)
+                } else {
+                    Err(UnresolvedPath {
+                        item_id,
+                        module_id,
+                        partial_res: None,
+                        unresolved: path_root.into(),
+                    })
+                }
+            })
+            .map(|(res, def_id)| (res, Some(def_id)))
+    }
+
+    /// Convert a DefId to a Res, where possible.
+    ///
+    /// This is used for resolving type aliases.
+    fn def_id_to_res(&self, ty_id: DefId) -> Option {
+        use PrimitiveType::*;
+        Some(match *self.cx.tcx.type_of(ty_id).kind() {
+            ty::Bool => Res::Primitive(Bool),
+            ty::Char => Res::Primitive(Char),
+            ty::Int(ity) => Res::Primitive(ity.into()),
+            ty::Uint(uty) => Res::Primitive(uty.into()),
+            ty::Float(fty) => Res::Primitive(fty.into()),
+            ty::Str => Res::Primitive(Str),
+            ty::Tuple(tys) if tys.is_empty() => Res::Primitive(Unit),
+            ty::Tuple(_) => Res::Primitive(Tuple),
+            ty::Array(..) => Res::Primitive(Array),
+            ty::Slice(_) => Res::Primitive(Slice),
+            ty::RawPtr(_) => Res::Primitive(RawPointer),
+            ty::Ref(..) => Res::Primitive(Reference),
+            ty::FnDef(..) => panic!("type alias to a function definition"),
+            ty::FnPtr(_) => Res::Primitive(Fn),
+            ty::Never => Res::Primitive(Never),
+            ty::Adt(ty::AdtDef(Interned(&ty::AdtDefData { did, .. }, _)), _) | ty::Foreign(did) => {
+                Res::from_def_id(self.cx.tcx, did)
+            }
+            ty::Projection(_)
+            | ty::Closure(..)
+            | ty::Generator(..)
+            | ty::GeneratorWitness(_)
+            | ty::Opaque(..)
+            | ty::Dynamic(..)
+            | ty::Param(_)
+            | ty::Bound(..)
+            | ty::Placeholder(_)
+            | ty::Infer(_)
+            | ty::Error(_) => return None,
+        })
+    }
+
+    /// Convert a PrimitiveType to a Ty, where possible.
+    ///
+    /// This is used for resolving trait impls for primitives
+    fn primitive_type_to_ty(&mut self, prim: PrimitiveType) -> Option> {
+        use PrimitiveType::*;
+        let tcx = self.cx.tcx;
+
+        // FIXME: Only simple types are supported here, see if we can support
+        // other types such as Tuple, Array, Slice, etc.
+        // See https://github.com/rust-lang/rust/issues/90703#issuecomment-1004263455
+        Some(tcx.mk_ty(match prim {
+            Bool => ty::Bool,
+            Str => ty::Str,
+            Char => ty::Char,
+            Never => ty::Never,
+            I8 => ty::Int(ty::IntTy::I8),
+            I16 => ty::Int(ty::IntTy::I16),
+            I32 => ty::Int(ty::IntTy::I32),
+            I64 => ty::Int(ty::IntTy::I64),
+            I128 => ty::Int(ty::IntTy::I128),
+            Isize => ty::Int(ty::IntTy::Isize),
+            F32 => ty::Float(ty::FloatTy::F32),
+            F64 => ty::Float(ty::FloatTy::F64),
+            U8 => ty::Uint(ty::UintTy::U8),
+            U16 => ty::Uint(ty::UintTy::U16),
+            U32 => ty::Uint(ty::UintTy::U32),
+            U64 => ty::Uint(ty::UintTy::U64),
+            U128 => ty::Uint(ty::UintTy::U128),
+            Usize => ty::Uint(ty::UintTy::Usize),
+            _ => return None,
+        }))
+    }
+
+    /// Resolve an associated item, returning its containing page's `Res`
+    /// and the fragment targeting the associated item on its page.
+    fn resolve_associated_item(
+        &mut self,
+        root_res: Res,
+        item_name: Symbol,
+        ns: Namespace,
+        module_id: DefId,
+    ) -> Option<(Res, DefId)> {
+        let tcx = self.cx.tcx;
+
+        match root_res {
+            Res::Primitive(prim) => {
+                self.resolve_primitive_associated_item(prim, ns, item_name).or_else(|| {
+                    self.primitive_type_to_ty(prim)
+                        .and_then(|ty| {
+                            resolve_associated_trait_item(ty, module_id, item_name, ns, self.cx)
+                        })
+                        .map(|item| (root_res, item.def_id))
+                })
+            }
+            Res::Def(DefKind::TyAlias, did) => {
+                // Resolve the link on the type the alias points to.
+                // FIXME: if the associated item is defined directly on the type alias,
+                // it will show up on its documentation page, we should link there instead.
+                let res = self.def_id_to_res(did)?;
+                self.resolve_associated_item(res, item_name, ns, module_id)
+            }
+            Res::Def(
+                def_kind @ (DefKind::Struct | DefKind::Union | DefKind::Enum | DefKind::ForeignTy),
+                did,
+            ) => {
+                debug!("looking for associated item named {} for item {:?}", item_name, did);
+                // Checks if item_name is a variant of the `SomeItem` enum
+                if ns == TypeNS && def_kind == DefKind::Enum {
+                    match tcx.type_of(did).kind() {
+                        ty::Adt(adt_def, _) => {
+                            for variant in adt_def.variants() {
+                                if variant.name == item_name {
+                                    return Some((root_res, variant.def_id));
+                                }
+                            }
+                        }
+                        _ => unreachable!(),
+                    }
+                }
+
+                // Checks if item_name belongs to `impl SomeItem`
+                let assoc_item = tcx
+                    .inherent_impls(did)
+                    .iter()
+                    .flat_map(|&imp| {
+                        tcx.associated_items(imp).find_by_name_and_namespace(
+                            tcx,
+                            Ident::with_dummy_span(item_name),
+                            ns,
+                            imp,
+                        )
+                    })
+                    .copied()
+                    // There should only ever be one associated item that matches from any inherent impl
+                    .next()
+                    // Check if item_name belongs to `impl SomeTrait for SomeItem`
+                    // FIXME(#74563): This gives precedence to `impl SomeItem`:
+                    // Although having both would be ambiguous, use impl version for compatibility's sake.
+                    // To handle that properly resolve() would have to support
+                    // something like [`ambi_fn`](::ambi_fn)
+                    .or_else(|| {
+                        resolve_associated_trait_item(
+                            tcx.type_of(did),
+                            module_id,
+                            item_name,
+                            ns,
+                            self.cx,
+                        )
+                    });
+
+                debug!("got associated item {:?}", assoc_item);
+
+                if let Some(item) = assoc_item {
+                    return Some((root_res, item.def_id));
+                }
+
+                if ns != Namespace::ValueNS {
+                    return None;
+                }
+                debug!("looking for fields named {} for {:?}", item_name, did);
+                // FIXME: this doesn't really belong in `associated_item` (maybe `variant_field` is better?)
+                // NOTE: it's different from variant_field because it only resolves struct fields,
+                // not variant fields (2 path segments, not 3).
+                //
+                // We need to handle struct (and union) fields in this code because
+                // syntactically their paths are identical to associated item paths:
+                // `module::Type::field` and `module::Type::Assoc`.
+                //
+                // On the other hand, variant fields can't be mistaken for associated
+                // items because they look like this: `module::Type::Variant::field`.
+                //
+                // Variants themselves don't need to be handled here, even though
+                // they also look like associated items (`module::Type::Variant`),
+                // because they are real Rust syntax (unlike the intra-doc links
+                // field syntax) and are handled by the compiler's resolver.
+                let def = match tcx.type_of(did).kind() {
+                    ty::Adt(def, _) if !def.is_enum() => def,
+                    _ => return None,
+                };
+                let field =
+                    def.non_enum_variant().fields.iter().find(|item| item.name == item_name)?;
+                Some((root_res, field.did))
+            }
+            Res::Def(DefKind::Trait, did) => tcx
+                .associated_items(did)
+                .find_by_name_and_namespace(tcx, Ident::with_dummy_span(item_name), ns, did)
+                .map(|item| {
+                    let res = Res::Def(item.kind.as_def_kind(), item.def_id);
+                    (res, item.def_id)
+                }),
+            _ => None,
+        }
+    }
+}
+
+fn full_res(tcx: TyCtxt<'_>, (base, assoc_item): (Res, Option)) -> Res {
+    assoc_item.map_or(base, |def_id| Res::from_def_id(tcx, def_id))
+}
+
+/// Look to see if a resolved item has an associated item named `item_name`.
+///
+/// Given `[std::io::Error::source]`, where `source` is unresolved, this would
+/// find `std::error::Error::source` and return
+/// `::source`.
+fn resolve_associated_trait_item<'a>(
+    ty: Ty<'a>,
+    module: DefId,
+    item_name: Symbol,
+    ns: Namespace,
+    cx: &mut DocContext<'a>,
+) -> Option {
+    // FIXME: this should also consider blanket impls (`impl X for T`). Unfortunately
+    // `get_auto_trait_and_blanket_impls` is broken because the caching behavior is wrong. In the
+    // meantime, just don't look for these blanket impls.
+
+    // Next consider explicit impls: `impl MyTrait for MyType`
+    // Give precedence to inherent impls.
+    let traits = trait_impls_for(cx, ty, module);
+    debug!("considering traits {:?}", traits);
+    let mut candidates = traits.iter().filter_map(|&(impl_, trait_)| {
+        cx.tcx
+            .associated_items(trait_)
+            .find_by_name_and_namespace(cx.tcx, Ident::with_dummy_span(item_name), ns, trait_)
+            .map(|trait_assoc| {
+                trait_assoc_to_impl_assoc_item(cx.tcx, impl_, trait_assoc.def_id)
+                    .unwrap_or(trait_assoc)
+            })
+    });
+    // FIXME(#74563): warn about ambiguity
+    debug!("the candidates were {:?}", candidates.clone().collect::>());
+    candidates.next().copied()
+}
+
+/// Find the associated item in the impl `impl_id` that corresponds to the
+/// trait associated item `trait_assoc_id`.
+///
+/// This function returns `None` if no associated item was found in the impl.
+/// This can occur when the trait associated item has a default value that is
+/// not overridden in the impl.
+///
+/// This is just a wrapper around [`TyCtxt::impl_item_implementor_ids()`] and
+/// [`TyCtxt::associated_item()`] (with some helpful logging added).
+#[instrument(level = "debug", skip(tcx))]
+fn trait_assoc_to_impl_assoc_item<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    impl_id: DefId,
+    trait_assoc_id: DefId,
+) -> Option<&'tcx ty::AssocItem> {
+    let trait_to_impl_assoc_map = tcx.impl_item_implementor_ids(impl_id);
+    debug!(?trait_to_impl_assoc_map);
+    let impl_assoc_id = *trait_to_impl_assoc_map.get(&trait_assoc_id)?;
+    debug!(?impl_assoc_id);
+    let impl_assoc = tcx.associated_item(impl_assoc_id);
+    debug!(?impl_assoc);
+    Some(impl_assoc)
+}
+
+/// Given a type, return all trait impls in scope in `module` for that type.
+/// Returns a set of pairs of `(impl_id, trait_id)`.
+///
+/// NOTE: this cannot be a query because more traits could be available when more crates are compiled!
+/// So it is not stable to serialize cross-crate.
+#[instrument(level = "debug", skip(cx))]
+fn trait_impls_for<'a>(
+    cx: &mut DocContext<'a>,
+    ty: Ty<'a>,
+    module: DefId,
+) -> FxHashSet<(DefId, DefId)> {
+    let tcx = cx.tcx;
+    let iter = cx.resolver_caches.traits_in_scope[&module].iter().flat_map(|trait_candidate| {
+        let trait_ = trait_candidate.def_id;
+        trace!("considering explicit impl for trait {:?}", trait_);
+
+        // Look at each trait implementation to see if it's an impl for `did`
+        tcx.find_map_relevant_impl(trait_, ty, |impl_| {
+            let trait_ref = tcx.impl_trait_ref(impl_).expect("this is not an inherent impl");
+            // Check if these are the same type.
+            let impl_type = trait_ref.self_ty();
+            trace!(
+                "comparing type {} with kind {:?} against type {:?}",
+                impl_type,
+                impl_type.kind(),
+                ty
+            );
+            // Fast path: if this is a primitive simple `==` will work
+            // NOTE: the `match` is necessary; see #92662.
+            // this allows us to ignore generics because the user input
+            // may not include the generic placeholders
+            // e.g. this allows us to match Foo (user comment) with Foo (actual type)
+            let saw_impl = impl_type == ty
+                || match (impl_type.kind(), ty.kind()) {
+                    (ty::Adt(impl_def, _), ty::Adt(ty_def, _)) => {
+                        debug!("impl def_id: {:?}, ty def_id: {:?}", impl_def.did(), ty_def.did());
+                        impl_def.did() == ty_def.did()
+                    }
+                    _ => false,
+                };
+
+            if saw_impl { Some((impl_, trait_)) } else { None }
+        })
+    });
+    iter.collect()
+}
+
+/// Check for resolve collisions between a trait and its derive.
+///
+/// These are common and we should just resolve to the trait in that case.
+fn is_derive_trait_collision(ns: &PerNS>>) -> bool {
+    matches!(
+        *ns,
+        PerNS {
+            type_ns: Ok((Res::Def(DefKind::Trait, _), _)),
+            macro_ns: Ok((Res::Def(DefKind::Macro(MacroKind::Derive), _), _)),
+            ..
+        }
+    )
+}
+
+impl<'a, 'tcx> DocVisitor for LinkCollector<'a, 'tcx> {
+    fn visit_item(&mut self, item: &Item) {
+        let parent_node =
+            item.item_id.as_def_id().and_then(|did| find_nearest_parent_module(self.cx.tcx, did));
+        if parent_node.is_some() {
+            trace!("got parent node for {:?} {:?}, id {:?}", item.type_(), item.name, item.item_id);
+        }
+
+        let inner_docs = item.inner_docs(self.cx.tcx);
+
+        if item.is_mod() && inner_docs {
+            self.mod_ids.push(item.item_id.expect_def_id());
+        }
+
+        // We want to resolve in the lexical scope of the documentation.
+        // In the presence of re-exports, this is not the same as the module of the item.
+        // Rather than merging all documentation into one, resolve it one attribute at a time
+        // so we know which module it came from.
+        for (parent_module, doc) in item.attrs.prepare_to_doc_link_resolution() {
+            if !may_have_doc_links(&doc) {
+                continue;
+            }
+            debug!("combined_docs={}", doc);
+            // NOTE: if there are links that start in one crate and end in another, this will not resolve them.
+            // This is a degenerate case and it's not supported by rustdoc.
+            let parent_node = parent_module.or(parent_node);
+            let mut tmp_links = self
+                .cx
+                .resolver_caches
+                .markdown_links
+                .take()
+                .expect("`markdown_links` are already borrowed");
+            if !tmp_links.contains_key(&doc) {
+                tmp_links.insert(doc.clone(), preprocessed_markdown_links(&doc));
+            }
+            for md_link in &tmp_links[&doc] {
+                let link = self.resolve_link(item, &doc, parent_node, md_link);
+                if let Some(link) = link {
+                    self.cx.cache.intra_doc_links.entry(item.item_id).or_default().push(link);
+                }
+            }
+            self.cx.resolver_caches.markdown_links = Some(tmp_links);
+        }
+
+        if item.is_mod() {
+            if !inner_docs {
+                self.mod_ids.push(item.item_id.expect_def_id());
+            }
+
+            self.visit_item_recur(item);
+            self.mod_ids.pop();
+        } else {
+            self.visit_item_recur(item)
+        }
+    }
+}
+
+enum PreprocessingError {
+    /// User error: `[std#x#y]` is not valid
+    MultipleAnchors,
+    Disambiguator(Range, String),
+    MalformedGenerics(MalformedGenerics, String),
+}
+
+impl PreprocessingError {
+    fn report(&self, cx: &DocContext<'_>, diag_info: DiagnosticInfo<'_>) {
+        match self {
+            PreprocessingError::MultipleAnchors => report_multiple_anchors(cx, diag_info),
+            PreprocessingError::Disambiguator(range, msg) => {
+                disambiguator_error(cx, diag_info, range.clone(), msg)
+            }
+            PreprocessingError::MalformedGenerics(err, path_str) => {
+                report_malformed_generics(cx, diag_info, *err, path_str)
+            }
+        }
+    }
+}
+
+#[derive(Clone)]
+struct PreprocessingInfo {
+    path_str: String,
+    disambiguator: Option,
+    extra_fragment: Option,
+    link_text: String,
+}
+
+// Not a typedef to avoid leaking several private structures from this module.
+pub(crate) struct PreprocessedMarkdownLink(
+    Result,
+    MarkdownLink,
+);
+
+/// Returns:
+/// - `None` if the link should be ignored.
+/// - `Some(Err)` if the link should emit an error
+/// - `Some(Ok)` if the link is valid
+///
+/// `link_buffer` is needed for lifetime reasons; it will always be overwritten and the contents ignored.
+fn preprocess_link(
+    ori_link: &MarkdownLink,
+) -> Option> {
+    // [] is mostly likely not supposed to be a link
+    if ori_link.link.is_empty() {
+        return None;
+    }
+
+    // Bail early for real links.
+    if ori_link.link.contains('/') {
+        return None;
+    }
+
+    let stripped = ori_link.link.replace('`', "");
+    let mut parts = stripped.split('#');
+
+    let link = parts.next().unwrap();
+    if link.trim().is_empty() {
+        // This is an anchor to an element of the current page, nothing to do in here!
+        return None;
+    }
+    let extra_fragment = parts.next();
+    if parts.next().is_some() {
+        // A valid link can't have multiple #'s
+        return Some(Err(PreprocessingError::MultipleAnchors));
+    }
+
+    // Parse and strip the disambiguator from the link, if present.
+    let (disambiguator, path_str, link_text) = match Disambiguator::from_str(link) {
+        Ok(Some((d, path, link_text))) => (Some(d), path.trim(), link_text.trim()),
+        Ok(None) => (None, link.trim(), link.trim()),
+        Err((err_msg, relative_range)) => {
+            // Only report error if we would not have ignored this link. See issue #83859.
+            if !should_ignore_link_with_disambiguators(link) {
+                let no_backticks_range = range_between_backticks(ori_link);
+                let disambiguator_range = (no_backticks_range.start + relative_range.start)
+                    ..(no_backticks_range.start + relative_range.end);
+                return Some(Err(PreprocessingError::Disambiguator(disambiguator_range, err_msg)));
+            } else {
+                return None;
+            }
+        }
+    };
+
+    if should_ignore_link(path_str) {
+        return None;
+    }
+
+    // Strip generics from the path.
+    let path_str = if path_str.contains(['<', '>'].as_slice()) {
+        match strip_generics_from_path(path_str) {
+            Ok(path) => path,
+            Err(err) => {
+                debug!("link has malformed generics: {}", path_str);
+                return Some(Err(PreprocessingError::MalformedGenerics(err, path_str.to_owned())));
+            }
+        }
+    } else {
+        path_str.to_owned()
+    };
+
+    // Sanity check to make sure we don't have any angle brackets after stripping generics.
+    assert!(!path_str.contains(['<', '>'].as_slice()));
+
+    // The link is not an intra-doc link if it still contains spaces after stripping generics.
+    if path_str.contains(' ') {
+        return None;
+    }
+
+    Some(Ok(PreprocessingInfo {
+        path_str,
+        disambiguator,
+        extra_fragment: extra_fragment.map(|frag| frag.to_owned()),
+        link_text: link_text.to_owned(),
+    }))
+}
+
+fn preprocessed_markdown_links(s: &str) -> Vec {
+    markdown_links(s, |link| {
+        preprocess_link(&link).map(|pp_link| PreprocessedMarkdownLink(pp_link, link))
+    })
+}
+
+impl LinkCollector<'_, '_> {
+    /// This is the entry point for resolving an intra-doc link.
+    ///
+    /// FIXME(jynelson): this is way too many arguments
+    fn resolve_link(
+        &mut self,
+        item: &Item,
+        dox: &str,
+        parent_node: Option,
+        link: &PreprocessedMarkdownLink,
+    ) -> Option {
+        let PreprocessedMarkdownLink(pp_link, ori_link) = link;
+        trace!("considering link '{}'", ori_link.link);
+
+        let diag_info = DiagnosticInfo {
+            item,
+            dox,
+            ori_link: &ori_link.link,
+            link_range: ori_link.range.clone(),
+        };
+
+        let PreprocessingInfo { path_str, disambiguator, extra_fragment, link_text } =
+            pp_link.as_ref().map_err(|err| err.report(self.cx, diag_info.clone())).ok()?;
+        let disambiguator = *disambiguator;
+
+        // In order to correctly resolve intra-doc links we need to
+        // pick a base AST node to work from.  If the documentation for
+        // this module came from an inner comment (//!) then we anchor
+        // our name resolution *inside* the module.  If, on the other
+        // hand it was an outer comment (///) then we anchor the name
+        // resolution in the parent module on the basis that the names
+        // used are more likely to be intended to be parent names.  For
+        // this, we set base_node to None for inner comments since
+        // we've already pushed this node onto the resolution stack but
+        // for outer comments we explicitly try and resolve against the
+        // parent_node first.
+        let inner_docs = item.inner_docs(self.cx.tcx);
+        let base_node =
+            if item.is_mod() && inner_docs { self.mod_ids.last().copied() } else { parent_node };
+        let module_id = base_node.expect("doc link without parent module");
+
+        let (mut res, fragment) = self.resolve_with_disambiguator_cached(
+            ResolutionInfo {
+                item_id: item.item_id,
+                module_id,
+                dis: disambiguator,
+                path_str: path_str.to_owned(),
+                extra_fragment: extra_fragment.clone(),
+            },
+            diag_info.clone(), // this struct should really be Copy, but Range is not :(
+            // For reference-style links we want to report only one error so unsuccessful
+            // resolutions are cached, for other links we want to report an error every
+            // time so they are not cached.
+            matches!(ori_link.kind, LinkType::Reference | LinkType::Shortcut),
+        )?;
+
+        // Check for a primitive which might conflict with a module
+        // Report the ambiguity and require that the user specify which one they meant.
+        // FIXME: could there ever be a primitive not in the type namespace?
+        if matches!(
+            disambiguator,
+            None | Some(Disambiguator::Namespace(Namespace::TypeNS) | Disambiguator::Primitive)
+        ) && !matches!(res, Res::Primitive(_))
+        {
+            if let Some(prim) = resolve_primitive(path_str, TypeNS) {
+                // `prim@char`
+                if matches!(disambiguator, Some(Disambiguator::Primitive)) {
+                    res = prim;
+                } else {
+                    // `[char]` when a `char` module is in scope
+                    let candidates = vec![res, prim];
+                    ambiguity_error(self.cx, diag_info, path_str, candidates);
+                    return None;
+                }
+            }
+        }
+
+        match res {
+            Res::Primitive(prim) => {
+                if let Some(UrlFragment::Item(id)) = fragment {
+                    // We're actually resolving an associated item of a primitive, so we need to
+                    // verify the disambiguator (if any) matches the type of the associated item.
+                    // This case should really follow the same flow as the `Res::Def` branch below,
+                    // but attempting to add a call to `clean::register_res` causes an ICE. @jyn514
+                    // thinks `register_res` is only needed for cross-crate re-exports, but Rust
+                    // doesn't allow statements like `use str::trim;`, making this a (hopefully)
+                    // valid omission. See https://github.com/rust-lang/rust/pull/80660#discussion_r551585677
+                    // for discussion on the matter.
+                    let kind = self.cx.tcx.def_kind(id);
+                    self.verify_disambiguator(
+                        path_str,
+                        ori_link,
+                        kind,
+                        id,
+                        disambiguator,
+                        item,
+                        &diag_info,
+                    )?;
+
+                    // FIXME: it would be nice to check that the feature gate was enabled in the original crate, not just ignore it altogether.
+                    // However I'm not sure how to check that across crates.
+                    if prim == PrimitiveType::RawPointer
+                        && item.item_id.is_local()
+                        && !self.cx.tcx.features().intra_doc_pointers
+                    {
+                        self.report_rawptr_assoc_feature_gate(dox, ori_link, item);
+                    }
+                } else {
+                    match disambiguator {
+                        Some(Disambiguator::Primitive | Disambiguator::Namespace(_)) | None => {}
+                        Some(other) => {
+                            self.report_disambiguator_mismatch(
+                                path_str, ori_link, other, res, &diag_info,
+                            );
+                            return None;
+                        }
+                    }
+                }
+
+                Some(ItemLink {
+                    link: ori_link.link.clone(),
+                    link_text: link_text.clone(),
+                    did: res.def_id(self.cx.tcx),
+                    fragment,
+                })
+            }
+            Res::Def(kind, id) => {
+                let (kind_for_dis, id_for_dis) = if let Some(UrlFragment::Item(id)) = fragment {
+                    (self.cx.tcx.def_kind(id), id)
+                } else {
+                    (kind, id)
+                };
+                self.verify_disambiguator(
+                    path_str,
+                    ori_link,
+                    kind_for_dis,
+                    id_for_dis,
+                    disambiguator,
+                    item,
+                    &diag_info,
+                )?;
+                let id = clean::register_res(self.cx, rustc_hir::def::Res::Def(kind, id));
+                Some(ItemLink {
+                    link: ori_link.link.clone(),
+                    link_text: link_text.clone(),
+                    did: id,
+                    fragment,
+                })
+            }
+        }
+    }
+
+    fn verify_disambiguator(
+        &self,
+        path_str: &str,
+        ori_link: &MarkdownLink,
+        kind: DefKind,
+        id: DefId,
+        disambiguator: Option,
+        item: &Item,
+        diag_info: &DiagnosticInfo<'_>,
+    ) -> Option<()> {
+        debug!("intra-doc link to {} resolved to {:?}", path_str, (kind, id));
+
+        // Disallow e.g. linking to enums with `struct@`
+        debug!("saw kind {:?} with disambiguator {:?}", kind, disambiguator);
+        match (kind, disambiguator) {
+                | (DefKind::Const | DefKind::ConstParam | DefKind::AssocConst | DefKind::AnonConst, Some(Disambiguator::Kind(DefKind::Const)))
+                // NOTE: this allows 'method' to mean both normal functions and associated functions
+                // This can't cause ambiguity because both are in the same namespace.
+                | (DefKind::Fn | DefKind::AssocFn, Some(Disambiguator::Kind(DefKind::Fn)))
+                // These are namespaces; allow anything in the namespace to match
+                | (_, Some(Disambiguator::Namespace(_)))
+                // If no disambiguator given, allow anything
+                | (_, None)
+                // All of these are valid, so do nothing
+                => {}
+                (actual, Some(Disambiguator::Kind(expected))) if actual == expected => {}
+                (_, Some(specified @ Disambiguator::Kind(_) | specified @ Disambiguator::Primitive)) => {
+                    self.report_disambiguator_mismatch(path_str,ori_link,specified, Res::Def(kind, id),diag_info);
+                    return None;
+                }
+            }
+
+        // item can be non-local e.g. when using #[doc(primitive = "pointer")]
+        if let Some((src_id, dst_id)) = id
+            .as_local()
+            // The `expect_def_id()` should be okay because `local_def_id_to_hir_id`
+            // would presumably panic if a fake `DefIndex` were passed.
+            .and_then(|dst_id| {
+                item.item_id.expect_def_id().as_local().map(|src_id| (src_id, dst_id))
+            })
+        {
+            if self.cx.tcx.privacy_access_levels(()).is_exported(src_id)
+                && !self.cx.tcx.privacy_access_levels(()).is_exported(dst_id)
+            {
+                privacy_error(self.cx, diag_info, path_str);
+            }
+        }
+
+        Some(())
+    }
+
+    fn report_disambiguator_mismatch(
+        &self,
+        path_str: &str,
+        ori_link: &MarkdownLink,
+        specified: Disambiguator,
+        resolved: Res,
+        diag_info: &DiagnosticInfo<'_>,
+    ) {
+        // The resolved item did not match the disambiguator; give a better error than 'not found'
+        let msg = format!("incompatible link kind for `{}`", path_str);
+        let callback = |diag: &mut Diagnostic, sp: Option| {
+            let note = format!(
+                "this link resolved to {} {}, which is not {} {}",
+                resolved.article(),
+                resolved.descr(),
+                specified.article(),
+                specified.descr(),
+            );
+            if let Some(sp) = sp {
+                diag.span_label(sp, ¬e);
+            } else {
+                diag.note(¬e);
+            }
+            suggest_disambiguator(resolved, diag, path_str, &ori_link.link, sp);
+        };
+        report_diagnostic(self.cx.tcx, BROKEN_INTRA_DOC_LINKS, &msg, diag_info, callback);
+    }
+
+    fn report_rawptr_assoc_feature_gate(&self, dox: &str, ori_link: &MarkdownLink, item: &Item) {
+        let span =
+            super::source_span_for_markdown_range(self.cx.tcx, dox, &ori_link.range, &item.attrs)
+                .unwrap_or_else(|| item.attr_span(self.cx.tcx));
+        rustc_session::parse::feature_err(
+            &self.cx.tcx.sess.parse_sess,
+            sym::intra_doc_pointers,
+            span,
+            "linking to associated items of raw pointers is experimental",
+        )
+        .note("rustdoc does not allow disambiguating between `*const` and `*mut`, and pointers are unstable until it does")
+        .emit();
+    }
+
+    fn resolve_with_disambiguator_cached(
+        &mut self,
+        key: ResolutionInfo,
+        diag: DiagnosticInfo<'_>,
+        // If errors are cached then they are only reported on first ocurrence
+        // which we want in some cases but not in others.
+        cache_errors: bool,
+    ) -> Option<(Res, Option)> {
+        if let Some(res) = self.visited_links.get(&key) {
+            if res.is_some() || cache_errors {
+                return res.clone();
+            }
+        }
+
+        let res = self.resolve_with_disambiguator(&key, diag.clone()).and_then(|(res, def_id)| {
+            let fragment = match (&key.extra_fragment, def_id) {
+                (Some(_), Some(def_id)) => {
+                    report_anchor_conflict(self.cx, diag, def_id);
+                    return None;
+                }
+                (Some(u_frag), None) => Some(UrlFragment::UserWritten(u_frag.clone())),
+                (None, Some(def_id)) => Some(UrlFragment::Item(def_id)),
+                (None, None) => None,
+            };
+            Some((res, fragment))
+        });
+
+        if res.is_some() || cache_errors {
+            self.visited_links.insert(key, res.clone());
+        }
+        res
+    }
+
+    /// After parsing the disambiguator, resolve the main part of the link.
+    // FIXME(jynelson): wow this is just so much
+    fn resolve_with_disambiguator(
+        &mut self,
+        key: &ResolutionInfo,
+        diag: DiagnosticInfo<'_>,
+    ) -> Option<(Res, Option)> {
+        let disambiguator = key.dis;
+        let path_str = &key.path_str;
+        let item_id = key.item_id;
+        let base_node = key.module_id;
+
+        match disambiguator.map(Disambiguator::ns) {
+            Some(expected_ns) => {
+                match self.resolve(path_str, expected_ns, item_id, base_node) {
+                    Ok(res) => Some(res),
+                    Err(err) => {
+                        // We only looked in one namespace. Try to give a better error if possible.
+                        // FIXME: really it should be `resolution_failure` that does this, not `resolve_with_disambiguator`.
+                        // See https://github.com/rust-lang/rust/pull/76955#discussion_r493953382 for a good approach.
+                        let mut err = ResolutionFailure::NotResolved(err);
+                        for other_ns in [TypeNS, ValueNS, MacroNS] {
+                            if other_ns != expected_ns {
+                                if let Ok(res) =
+                                    self.resolve(path_str, other_ns, item_id, base_node)
+                                {
+                                    err = ResolutionFailure::WrongNamespace {
+                                        res: full_res(self.cx.tcx, res),
+                                        expected_ns,
+                                    };
+                                    break;
+                                }
+                            }
+                        }
+                        resolution_failure(self, diag, path_str, disambiguator, smallvec![err])
+                    }
+                }
+            }
+            None => {
+                // Try everything!
+                let mut candidate = |ns| {
+                    self.resolve(path_str, ns, item_id, base_node)
+                        .map_err(ResolutionFailure::NotResolved)
+                };
+
+                let candidates = PerNS {
+                    macro_ns: candidate(MacroNS),
+                    type_ns: candidate(TypeNS),
+                    value_ns: candidate(ValueNS).and_then(|(res, def_id)| {
+                        match res {
+                            // Constructors are picked up in the type namespace.
+                            Res::Def(DefKind::Ctor(..), _) => {
+                                Err(ResolutionFailure::WrongNamespace { res, expected_ns: TypeNS })
+                            }
+                            _ => Ok((res, def_id)),
+                        }
+                    }),
+                };
+
+                let len = candidates.iter().filter(|res| res.is_ok()).count();
+
+                if len == 0 {
+                    return resolution_failure(
+                        self,
+                        diag,
+                        path_str,
+                        disambiguator,
+                        candidates.into_iter().filter_map(|res| res.err()).collect(),
+                    );
+                }
+
+                if len == 1 {
+                    Some(candidates.into_iter().find_map(|res| res.ok()).unwrap())
+                } else if len == 2 && is_derive_trait_collision(&candidates) {
+                    Some(candidates.type_ns.unwrap())
+                } else {
+                    let ignore_macro = is_derive_trait_collision(&candidates);
+                    // If we're reporting an ambiguity, don't mention the namespaces that failed
+                    let mut candidates =
+                        candidates.map(|candidate| candidate.ok().map(|(res, _)| res));
+                    if ignore_macro {
+                        candidates.macro_ns = None;
+                    }
+                    ambiguity_error(self.cx, diag, path_str, candidates.present_items().collect());
+                    None
+                }
+            }
+        }
+    }
+}
+
+/// Get the section of a link between the backticks,
+/// or the whole link if there aren't any backticks.
+///
+/// For example:
+///
+/// ```text
+/// [`Foo`]
+///   ^^^
+/// ```
+fn range_between_backticks(ori_link: &MarkdownLink) -> Range {
+    let after_first_backtick_group = ori_link.link.bytes().position(|b| b != b'`').unwrap_or(0);
+    let before_second_backtick_group = ori_link
+        .link
+        .bytes()
+        .skip(after_first_backtick_group)
+        .position(|b| b == b'`')
+        .unwrap_or(ori_link.link.len());
+    (ori_link.range.start + after_first_backtick_group)
+        ..(ori_link.range.start + before_second_backtick_group)
+}
+
+/// Returns true if we should ignore `link` due to it being unlikely
+/// that it is an intra-doc link. `link` should still have disambiguators
+/// if there were any.
+///
+/// The difference between this and [`should_ignore_link()`] is that this
+/// check should only be used on links that still have disambiguators.
+fn should_ignore_link_with_disambiguators(link: &str) -> bool {
+    link.contains(|ch: char| !(ch.is_alphanumeric() || ":_<>, !*&;@()".contains(ch)))
+}
+
+/// Returns true if we should ignore `path_str` due to it being unlikely
+/// that it is an intra-doc link.
+fn should_ignore_link(path_str: &str) -> bool {
+    path_str.contains(|ch: char| !(ch.is_alphanumeric() || ":_<>, !*&;".contains(ch)))
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
+/// Disambiguators for a link.
+enum Disambiguator {
+    /// `prim@`
+    ///
+    /// This is buggy, see 
+    Primitive,
+    /// `struct@` or `f()`
+    Kind(DefKind),
+    /// `type@`
+    Namespace(Namespace),
+}
+
+impl Disambiguator {
+    /// Given a link, parse and return `(disambiguator, path_str, link_text)`.
+    ///
+    /// This returns `Ok(Some(...))` if a disambiguator was found,
+    /// `Ok(None)` if no disambiguator was found, or `Err(...)`
+    /// if there was a problem with the disambiguator.
+    fn from_str(link: &str) -> Result, (String, Range)> {
+        use Disambiguator::{Kind, Namespace as NS, Primitive};
+
+        if let Some(idx) = link.find('@') {
+            let (prefix, rest) = link.split_at(idx);
+            let d = match prefix {
+                "struct" => Kind(DefKind::Struct),
+                "enum" => Kind(DefKind::Enum),
+                "trait" => Kind(DefKind::Trait),
+                "union" => Kind(DefKind::Union),
+                "module" | "mod" => Kind(DefKind::Mod),
+                "const" | "constant" => Kind(DefKind::Const),
+                "static" => Kind(DefKind::Static(Mutability::Not)),
+                "function" | "fn" | "method" => Kind(DefKind::Fn),
+                "derive" => Kind(DefKind::Macro(MacroKind::Derive)),
+                "type" => NS(Namespace::TypeNS),
+                "value" => NS(Namespace::ValueNS),
+                "macro" => NS(Namespace::MacroNS),
+                "prim" | "primitive" => Primitive,
+                _ => return Err((format!("unknown disambiguator `{}`", prefix), 0..idx)),
+            };
+            Ok(Some((d, &rest[1..], &rest[1..])))
+        } else {
+            let suffixes = [
+                ("!()", DefKind::Macro(MacroKind::Bang)),
+                ("!{}", DefKind::Macro(MacroKind::Bang)),
+                ("![]", DefKind::Macro(MacroKind::Bang)),
+                ("()", DefKind::Fn),
+                ("!", DefKind::Macro(MacroKind::Bang)),
+            ];
+            for (suffix, kind) in suffixes {
+                if let Some(path_str) = link.strip_suffix(suffix) {
+                    // Avoid turning `!` or `()` into an empty string
+                    if !path_str.is_empty() {
+                        return Ok(Some((Kind(kind), path_str, link)));
+                    }
+                }
+            }
+            Ok(None)
+        }
+    }
+
+    fn ns(self) -> Namespace {
+        match self {
+            Self::Namespace(n) => n,
+            Self::Kind(k) => {
+                k.ns().expect("only DefKinds with a valid namespace can be disambiguators")
+            }
+            Self::Primitive => TypeNS,
+        }
+    }
+
+    fn article(self) -> &'static str {
+        match self {
+            Self::Namespace(_) => panic!("article() doesn't make sense for namespaces"),
+            Self::Kind(k) => k.article(),
+            Self::Primitive => "a",
+        }
+    }
+
+    fn descr(self) -> &'static str {
+        match self {
+            Self::Namespace(n) => n.descr(),
+            // HACK(jynelson): the source of `DefKind::descr` only uses the DefId for
+            // printing "module" vs "crate" so using the wrong ID is not a huge problem
+            Self::Kind(k) => k.descr(CRATE_DEF_ID.to_def_id()),
+            Self::Primitive => "builtin type",
+        }
+    }
+}
+
+/// A suggestion to show in a diagnostic.
+enum Suggestion {
+    /// `struct@`
+    Prefix(&'static str),
+    /// `f()`
+    Function,
+    /// `m!`
+    Macro,
+    /// `foo` without any disambiguator
+    RemoveDisambiguator,
+}
+
+impl Suggestion {
+    fn descr(&self) -> Cow<'static, str> {
+        match self {
+            Self::Prefix(x) => format!("prefix with `{}@`", x).into(),
+            Self::Function => "add parentheses".into(),
+            Self::Macro => "add an exclamation mark".into(),
+            Self::RemoveDisambiguator => "remove the disambiguator".into(),
+        }
+    }
+
+    fn as_help(&self, path_str: &str) -> String {
+        // FIXME: if this is an implied shortcut link, it's bad style to suggest `@`
+        match self {
+            Self::Prefix(prefix) => format!("{}@{}", prefix, path_str),
+            Self::Function => format!("{}()", path_str),
+            Self::Macro => format!("{}!", path_str),
+            Self::RemoveDisambiguator => path_str.into(),
+        }
+    }
+
+    fn as_help_span(
+        &self,
+        path_str: &str,
+        ori_link: &str,
+        sp: rustc_span::Span,
+    ) -> Vec<(rustc_span::Span, String)> {
+        let inner_sp = match ori_link.find('(') {
+            Some(index) => sp.with_hi(sp.lo() + BytePos(index as _)),
+            None => sp,
+        };
+        let inner_sp = match ori_link.find('!') {
+            Some(index) => inner_sp.with_hi(inner_sp.lo() + BytePos(index as _)),
+            None => inner_sp,
+        };
+        let inner_sp = match ori_link.find('@') {
+            Some(index) => inner_sp.with_lo(inner_sp.lo() + BytePos(index as u32 + 1)),
+            None => inner_sp,
+        };
+        match self {
+            Self::Prefix(prefix) => {
+                // FIXME: if this is an implied shortcut link, it's bad style to suggest `@`
+                let mut sugg = vec![(sp.with_hi(inner_sp.lo()), format!("{}@", prefix))];
+                if sp.hi() != inner_sp.hi() {
+                    sugg.push((inner_sp.shrink_to_hi().with_hi(sp.hi()), String::new()));
+                }
+                sugg
+            }
+            Self::Function => {
+                let mut sugg = vec![(inner_sp.shrink_to_hi().with_hi(sp.hi()), "()".to_string())];
+                if sp.lo() != inner_sp.lo() {
+                    sugg.push((inner_sp.shrink_to_lo().with_lo(sp.lo()), String::new()));
+                }
+                sugg
+            }
+            Self::Macro => {
+                let mut sugg = vec![(inner_sp.shrink_to_hi(), "!".to_string())];
+                if sp.lo() != inner_sp.lo() {
+                    sugg.push((inner_sp.shrink_to_lo().with_lo(sp.lo()), String::new()));
+                }
+                sugg
+            }
+            Self::RemoveDisambiguator => vec![(sp, path_str.into())],
+        }
+    }
+}
+
+/// Reports a diagnostic for an intra-doc link.
+///
+/// If no link range is provided, or the source span of the link cannot be determined, the span of
+/// the entire documentation block is used for the lint. If a range is provided but the span
+/// calculation fails, a note is added to the diagnostic pointing to the link in the markdown.
+///
+/// The `decorate` callback is invoked in all cases to allow further customization of the
+/// diagnostic before emission. If the span of the link was able to be determined, the second
+/// parameter of the callback will contain it, and the primary span of the diagnostic will be set
+/// to it.
+fn report_diagnostic(
+    tcx: TyCtxt<'_>,
+    lint: &'static Lint,
+    msg: &str,
+    DiagnosticInfo { item, ori_link: _, dox, link_range }: &DiagnosticInfo<'_>,
+    decorate: impl FnOnce(&mut Diagnostic, Option),
+) {
+    let Some(hir_id) = DocContext::as_local_hir_id(tcx, item.item_id)
+    else {
+        // If non-local, no need to check anything.
+        info!("ignoring warning from parent crate: {}", msg);
+        return;
+    };
+
+    let sp = item.attr_span(tcx);
+
+    tcx.struct_span_lint_hir(lint, hir_id, sp, |lint| {
+        let mut diag = lint.build(msg);
+
+        let span =
+            super::source_span_for_markdown_range(tcx, dox, link_range, &item.attrs).map(|sp| {
+                if dox.as_bytes().get(link_range.start) == Some(&b'`')
+                    && dox.as_bytes().get(link_range.end - 1) == Some(&b'`')
+                {
+                    sp.with_lo(sp.lo() + BytePos(1)).with_hi(sp.hi() - BytePos(1))
+                } else {
+                    sp
+                }
+            });
+
+        if let Some(sp) = span {
+            diag.set_span(sp);
+        } else {
+            // blah blah blah\nblah\nblah [blah] blah blah\nblah blah
+            //                       ^     ~~~~
+            //                       |     link_range
+            //                       last_new_line_offset
+            let last_new_line_offset = dox[..link_range.start].rfind('\n').map_or(0, |n| n + 1);
+            let line = dox[last_new_line_offset..].lines().next().unwrap_or("");
+
+            // Print the line containing the `link_range` and manually mark it with '^'s.
+            diag.note(&format!(
+                "the link appears in this line:\n\n{line}\n\
+                     {indicator: ,
+    diag_info: DiagnosticInfo<'_>,
+    path_str: &str,
+    disambiguator: Option,
+    kinds: SmallVec<[ResolutionFailure<'_>; 3]>,
+) -> Option<(Res, Option)> {
+    let tcx = collector.cx.tcx;
+    let mut recovered_res = None;
+    report_diagnostic(
+        tcx,
+        BROKEN_INTRA_DOC_LINKS,
+        &format!("unresolved link to `{}`", path_str),
+        &diag_info,
+        |diag, sp| {
+            let item = |res: Res| format!("the {} `{}`", res.descr(), res.name(tcx),);
+            let assoc_item_not_allowed = |res: Res| {
+                let name = res.name(tcx);
+                format!(
+                    "`{}` is {} {}, not a module or type, and cannot have associated items",
+                    name,
+                    res.article(),
+                    res.descr()
+                )
+            };
+            // ignore duplicates
+            let mut variants_seen = SmallVec::<[_; 3]>::new();
+            for mut failure in kinds {
+                let variant = std::mem::discriminant(&failure);
+                if variants_seen.contains(&variant) {
+                    continue;
+                }
+                variants_seen.push(variant);
+
+                if let ResolutionFailure::NotResolved(UnresolvedPath {
+                    item_id,
+                    module_id,
+                    partial_res,
+                    unresolved,
+                }) = &mut failure
+                {
+                    use DefKind::*;
+
+                    let item_id = *item_id;
+                    let module_id = *module_id;
+                    // FIXME(jynelson): this might conflict with my `Self` fix in #76467
+                    // FIXME: maybe use itertools `collect_tuple` instead?
+                    fn split(path: &str) -> Option<(&str, &str)> {
+                        let mut splitter = path.rsplitn(2, "::");
+                        splitter.next().and_then(|right| splitter.next().map(|left| (left, right)))
+                    }
+
+                    // Check if _any_ parent of the path gets resolved.
+                    // If so, report it and say the first which failed; if not, say the first path segment didn't resolve.
+                    let mut name = path_str;
+                    'outer: loop {
+                        let Some((start, end)) = split(name) else {
+                            // avoid bug that marked [Quux::Z] as missing Z, not Quux
+                            if partial_res.is_none() {
+                                *unresolved = name.into();
+                            }
+                            break;
+                        };
+                        name = start;
+                        for ns in [TypeNS, ValueNS, MacroNS] {
+                            if let Ok(res) = collector.resolve(start, ns, item_id, module_id) {
+                                debug!("found partial_res={:?}", res);
+                                *partial_res = Some(full_res(collector.cx.tcx, res));
+                                *unresolved = end.into();
+                                break 'outer;
+                            }
+                        }
+                        *unresolved = end.into();
+                    }
+
+                    let last_found_module = match *partial_res {
+                        Some(Res::Def(DefKind::Mod, id)) => Some(id),
+                        None => Some(module_id),
+                        _ => None,
+                    };
+                    // See if this was a module: `[path]` or `[std::io::nope]`
+                    if let Some(module) = last_found_module {
+                        let note = if partial_res.is_some() {
+                            // Part of the link resolved; e.g. `std::io::nonexistent`
+                            let module_name = tcx.item_name(module);
+                            format!("no item named `{}` in module `{}`", unresolved, module_name)
+                        } else {
+                            // None of the link resolved; e.g. `Notimported`
+                            format!("no item named `{}` in scope", unresolved)
+                        };
+                        if let Some(span) = sp {
+                            diag.span_label(span, ¬e);
+                        } else {
+                            diag.note(¬e);
+                        }
+
+                        if !path_str.contains("::") {
+                            if disambiguator.map_or(true, |d| d.ns() == MacroNS)
+                                && let Some(&res) = collector.cx.resolver_caches.all_macro_rules
+                                                             .get(&Symbol::intern(path_str))
+                            {
+                                diag.note(format!(
+                                    "`macro_rules` named `{path_str}` exists in this crate, \
+                                     but it is not in scope at this link's location"
+                                ));
+                                recovered_res = res.try_into().ok().map(|res| (res, None));
+                            } else {
+                                // If the link has `::` in it, assume it was meant to be an
+                                // intra-doc link. Otherwise, the `[]` might be unrelated.
+                                diag.help("to escape `[` and `]` characters, \
+                                           add '\\' before them like `\\[` or `\\]`");
+                            }
+                        }
+
+                        continue;
+                    }
+
+                    // Otherwise, it must be an associated item or variant
+                    let res = partial_res.expect("None case was handled by `last_found_module`");
+                    let name = res.name(tcx);
+                    let kind = match res {
+                        Res::Def(kind, _) => Some(kind),
+                        Res::Primitive(_) => None,
+                    };
+                    let path_description = if let Some(kind) = kind {
+                        match kind {
+                            Mod | ForeignMod => "inner item",
+                            Struct => "field or associated item",
+                            Enum | Union => "variant or associated item",
+                            Variant
+                            | Field
+                            | Closure
+                            | Generator
+                            | AssocTy
+                            | AssocConst
+                            | AssocFn
+                            | Fn
+                            | Macro(_)
+                            | Const
+                            | ConstParam
+                            | ExternCrate
+                            | Use
+                            | LifetimeParam
+                            | Ctor(_, _)
+                            | AnonConst
+                            | InlineConst => {
+                                let note = assoc_item_not_allowed(res);
+                                if let Some(span) = sp {
+                                    diag.span_label(span, ¬e);
+                                } else {
+                                    diag.note(¬e);
+                                }
+                                return;
+                            }
+                            Trait | TyAlias | ForeignTy | OpaqueTy | TraitAlias | TyParam
+                            | Static(_) => "associated item",
+                            Impl | GlobalAsm => unreachable!("not a path"),
+                        }
+                    } else {
+                        "associated item"
+                    };
+                    let note = format!(
+                        "the {} `{}` has no {} named `{}`",
+                        res.descr(),
+                        name,
+                        disambiguator.map_or(path_description, |d| d.descr()),
+                        unresolved,
+                    );
+                    if let Some(span) = sp {
+                        diag.span_label(span, ¬e);
+                    } else {
+                        diag.note(¬e);
+                    }
+
+                    continue;
+                }
+                let note = match failure {
+                    ResolutionFailure::NotResolved { .. } => unreachable!("handled above"),
+                    ResolutionFailure::WrongNamespace { res, expected_ns } => {
+                        suggest_disambiguator(res, diag, path_str, diag_info.ori_link, sp);
+
+                        format!(
+                            "this link resolves to {}, which is not in the {} namespace",
+                            item(res),
+                            expected_ns.descr()
+                        )
+                    }
+                };
+                if let Some(span) = sp {
+                    diag.span_label(span, ¬e);
+                } else {
+                    diag.note(¬e);
+                }
+            }
+        },
+    );
+
+    recovered_res
+}
+
+fn report_multiple_anchors(cx: &DocContext<'_>, diag_info: DiagnosticInfo<'_>) {
+    let msg = format!("`{}` contains multiple anchors", diag_info.ori_link);
+    anchor_failure(cx, diag_info, &msg, 1)
+}
+
+fn report_anchor_conflict(cx: &DocContext<'_>, diag_info: DiagnosticInfo<'_>, def_id: DefId) {
+    let (link, kind) = (diag_info.ori_link, Res::from_def_id(cx.tcx, def_id).descr());
+    let msg = format!("`{link}` contains an anchor, but links to {kind}s are already anchored");
+    anchor_failure(cx, diag_info, &msg, 0)
+}
+
+/// Report an anchor failure.
+fn anchor_failure(
+    cx: &DocContext<'_>,
+    diag_info: DiagnosticInfo<'_>,
+    msg: &str,
+    anchor_idx: usize,
+) {
+    report_diagnostic(cx.tcx, BROKEN_INTRA_DOC_LINKS, msg, &diag_info, |diag, sp| {
+        if let Some(mut sp) = sp {
+            if let Some((fragment_offset, _)) =
+                diag_info.ori_link.char_indices().filter(|(_, x)| *x == '#').nth(anchor_idx)
+            {
+                sp = sp.with_lo(sp.lo() + BytePos(fragment_offset as _));
+            }
+            diag.span_label(sp, "invalid anchor");
+        }
+    });
+}
+
+/// Report an error in the link disambiguator.
+fn disambiguator_error(
+    cx: &DocContext<'_>,
+    mut diag_info: DiagnosticInfo<'_>,
+    disambiguator_range: Range,
+    msg: &str,
+) {
+    diag_info.link_range = disambiguator_range;
+    report_diagnostic(cx.tcx, BROKEN_INTRA_DOC_LINKS, msg, &diag_info, |diag, _sp| {
+        let msg = format!(
+            "see {}/rustdoc/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators",
+            crate::DOC_RUST_LANG_ORG_CHANNEL
+        );
+        diag.note(&msg);
+    });
+}
+
+fn report_malformed_generics(
+    cx: &DocContext<'_>,
+    diag_info: DiagnosticInfo<'_>,
+    err: MalformedGenerics,
+    path_str: &str,
+) {
+    report_diagnostic(
+        cx.tcx,
+        BROKEN_INTRA_DOC_LINKS,
+        &format!("unresolved link to `{}`", path_str),
+        &diag_info,
+        |diag, sp| {
+            let note = match err {
+                MalformedGenerics::UnbalancedAngleBrackets => "unbalanced angle brackets",
+                MalformedGenerics::MissingType => "missing type for generic parameters",
+                MalformedGenerics::HasFullyQualifiedSyntax => {
+                    diag.note(
+                        "see https://github.com/rust-lang/rust/issues/74563 for more information",
+                    );
+                    "fully-qualified syntax is unsupported"
+                }
+                MalformedGenerics::InvalidPathSeparator => "has invalid path separator",
+                MalformedGenerics::TooManyAngleBrackets => "too many angle brackets",
+                MalformedGenerics::EmptyAngleBrackets => "empty angle brackets",
+            };
+            if let Some(span) = sp {
+                diag.span_label(span, note);
+            } else {
+                diag.note(note);
+            }
+        },
+    );
+}
+
+/// Report an ambiguity error, where there were multiple possible resolutions.
+fn ambiguity_error(
+    cx: &DocContext<'_>,
+    diag_info: DiagnosticInfo<'_>,
+    path_str: &str,
+    candidates: Vec,
+) {
+    let mut msg = format!("`{}` is ", path_str);
+
+    match candidates.as_slice() {
+        [first_def, second_def] => {
+            msg += &format!(
+                "both {} {} and {} {}",
+                first_def.article(),
+                first_def.descr(),
+                second_def.article(),
+                second_def.descr(),
+            );
+        }
+        _ => {
+            let mut candidates = candidates.iter().peekable();
+            while let Some(res) = candidates.next() {
+                if candidates.peek().is_some() {
+                    msg += &format!("{} {}, ", res.article(), res.descr());
+                } else {
+                    msg += &format!("and {} {}", res.article(), res.descr());
+                }
+            }
+        }
+    }
+
+    report_diagnostic(cx.tcx, BROKEN_INTRA_DOC_LINKS, &msg, &diag_info, |diag, sp| {
+        if let Some(sp) = sp {
+            diag.span_label(sp, "ambiguous link");
+        } else {
+            diag.note("ambiguous link");
+        }
+
+        for res in candidates {
+            suggest_disambiguator(res, diag, path_str, diag_info.ori_link, sp);
+        }
+    });
+}
+
+/// In case of an ambiguity or mismatched disambiguator, suggest the correct
+/// disambiguator.
+fn suggest_disambiguator(
+    res: Res,
+    diag: &mut Diagnostic,
+    path_str: &str,
+    ori_link: &str,
+    sp: Option,
+) {
+    let suggestion = res.disambiguator_suggestion();
+    let help = format!("to link to the {}, {}", res.descr(), suggestion.descr());
+
+    if let Some(sp) = sp {
+        let mut spans = suggestion.as_help_span(path_str, ori_link, sp);
+        if spans.len() > 1 {
+            diag.multipart_suggestion(&help, spans, Applicability::MaybeIncorrect);
+        } else {
+            let (sp, suggestion_text) = spans.pop().unwrap();
+            diag.span_suggestion_verbose(sp, &help, suggestion_text, Applicability::MaybeIncorrect);
+        }
+    } else {
+        diag.help(&format!("{}: {}", help, suggestion.as_help(path_str)));
+    }
+}
+
+/// Report a link from a public item to a private one.
+fn privacy_error(cx: &DocContext<'_>, diag_info: &DiagnosticInfo<'_>, path_str: &str) {
+    let sym;
+    let item_name = match diag_info.item.name {
+        Some(name) => {
+            sym = name;
+            sym.as_str()
+        }
+        None => "",
+    };
+    let msg =
+        format!("public documentation for `{}` links to private item `{}`", item_name, path_str);
+
+    report_diagnostic(cx.tcx, PRIVATE_INTRA_DOC_LINKS, &msg, diag_info, |diag, sp| {
+        if let Some(sp) = sp {
+            diag.span_label(sp, "this item is private");
+        }
+
+        let note_msg = if cx.render_options.document_private {
+            "this link resolves only because you passed `--document-private-items`, but will break without"
+        } else {
+            "this link will resolve properly if you pass `--document-private-items`"
+        };
+        diag.note(note_msg);
+    });
+}
+
+/// Resolve a primitive type or value.
+fn resolve_primitive(path_str: &str, ns: Namespace) -> Option {
+    if ns != TypeNS {
+        return None;
+    }
+    use PrimitiveType::*;
+    let prim = match path_str {
+        "isize" => Isize,
+        "i8" => I8,
+        "i16" => I16,
+        "i32" => I32,
+        "i64" => I64,
+        "i128" => I128,
+        "usize" => Usize,
+        "u8" => U8,
+        "u16" => U16,
+        "u32" => U32,
+        "u64" => U64,
+        "u128" => U128,
+        "f32" => F32,
+        "f64" => F64,
+        "char" => Char,
+        "bool" | "true" | "false" => Bool,
+        "str" | "&str" => Str,
+        // See #80181 for why these don't have symbols associated.
+        "slice" => Slice,
+        "array" => Array,
+        "tuple" => Tuple,
+        "unit" => Unit,
+        "pointer" | "*const" | "*mut" => RawPointer,
+        "reference" | "&" | "&mut" => Reference,
+        "fn" => Fn,
+        "never" | "!" => Never,
+        _ => return None,
+    };
+    debug!("resolved primitives {:?}", prim);
+    Some(Res::Primitive(prim))
+}
+
+fn strip_generics_from_path(path_str: &str) -> Result {
+    let mut stripped_segments = vec![];
+    let mut path = path_str.chars().peekable();
+    let mut segment = Vec::new();
+
+    while let Some(chr) = path.next() {
+        match chr {
+            ':' => {
+                if path.next_if_eq(&':').is_some() {
+                    let stripped_segment =
+                        strip_generics_from_path_segment(mem::take(&mut segment))?;
+                    if !stripped_segment.is_empty() {
+                        stripped_segments.push(stripped_segment);
+                    }
+                } else {
+                    return Err(MalformedGenerics::InvalidPathSeparator);
+                }
+            }
+            '<' => {
+                segment.push(chr);
+
+                match path.next() {
+                    Some('<') => {
+                        return Err(MalformedGenerics::TooManyAngleBrackets);
+                    }
+                    Some('>') => {
+                        return Err(MalformedGenerics::EmptyAngleBrackets);
+                    }
+                    Some(chr) => {
+                        segment.push(chr);
+
+                        while let Some(chr) = path.next_if(|c| *c != '>') {
+                            segment.push(chr);
+                        }
+                    }
+                    None => break,
+                }
+            }
+            _ => segment.push(chr),
+        }
+        trace!("raw segment: {:?}", segment);
+    }
+
+    if !segment.is_empty() {
+        let stripped_segment = strip_generics_from_path_segment(segment)?;
+        if !stripped_segment.is_empty() {
+            stripped_segments.push(stripped_segment);
+        }
+    }
+
+    debug!("path_str: {:?}\nstripped segments: {:?}", path_str, &stripped_segments);
+
+    let stripped_path = stripped_segments.join("::");
+
+    if !stripped_path.is_empty() { Ok(stripped_path) } else { Err(MalformedGenerics::MissingType) }
+}
+
+fn strip_generics_from_path_segment(segment: Vec) -> Result {
+    let mut stripped_segment = String::new();
+    let mut param_depth = 0;
+
+    let mut latest_generics_chunk = String::new();
+
+    for c in segment {
+        if c == '<' {
+            param_depth += 1;
+            latest_generics_chunk.clear();
+        } else if c == '>' {
+            param_depth -= 1;
+            if latest_generics_chunk.contains(" as ") {
+                // The segment tries to use fully-qualified syntax, which is currently unsupported.
+                // Give a helpful error message instead of completely ignoring the angle brackets.
+                return Err(MalformedGenerics::HasFullyQualifiedSyntax);
+            }
+        } else {
+            if param_depth == 0 {
+                stripped_segment.push(c);
+            } else {
+                latest_generics_chunk.push(c);
+            }
+        }
+    }
+
+    if param_depth == 0 {
+        Ok(stripped_segment)
+    } else {
+        // The segment has unbalanced angle brackets, e.g. `Vec>`
+        Err(MalformedGenerics::UnbalancedAngleBrackets)
+    }
+}
diff --git a/src/librustdoc/passes/collect_intra_doc_links/early.rs b/src/librustdoc/passes/collect_intra_doc_links/early.rs
new file mode 100644
index 000000000..38cfd7a27
--- /dev/null
+++ b/src/librustdoc/passes/collect_intra_doc_links/early.rs
@@ -0,0 +1,405 @@
+use crate::clean::Attributes;
+use crate::core::ResolverCaches;
+use crate::passes::collect_intra_doc_links::preprocessed_markdown_links;
+use crate::passes::collect_intra_doc_links::{Disambiguator, PreprocessedMarkdownLink};
+
+use rustc_ast::visit::{self, AssocCtxt, Visitor};
+use rustc_ast::{self as ast, ItemKind};
+use rustc_data_structures::fx::FxHashMap;
+use rustc_hir::def::Namespace::*;
+use rustc_hir::def::{DefKind, Namespace, Res};
+use rustc_hir::def_id::{DefId, DefIdMap, DefIdSet, CRATE_DEF_ID};
+use rustc_hir::TraitCandidate;
+use rustc_middle::ty::{DefIdTree, Visibility};
+use rustc_resolve::{ParentScope, Resolver};
+use rustc_session::config::Externs;
+use rustc_session::Session;
+use rustc_span::symbol::sym;
+use rustc_span::{Symbol, SyntaxContext};
+
+use std::collections::hash_map::Entry;
+use std::mem;
+
+pub(crate) fn early_resolve_intra_doc_links(
+    resolver: &mut Resolver<'_>,
+    sess: &Session,
+    krate: &ast::Crate,
+    externs: Externs,
+    document_private_items: bool,
+) -> ResolverCaches {
+    let parent_scope =
+        ParentScope::module(resolver.expect_module(CRATE_DEF_ID.to_def_id()), resolver);
+    let mut link_resolver = EarlyDocLinkResolver {
+        resolver,
+        sess,
+        parent_scope,
+        visited_mods: Default::default(),
+        markdown_links: Default::default(),
+        doc_link_resolutions: Default::default(),
+        traits_in_scope: Default::default(),
+        all_traits: Default::default(),
+        all_trait_impls: Default::default(),
+        all_macro_rules: Default::default(),
+        document_private_items,
+    };
+
+    // Overridden `visit_item` below doesn't apply to the crate root,
+    // so we have to visit its attributes and reexports separately.
+    link_resolver.resolve_doc_links_local(&krate.attrs);
+    link_resolver.process_module_children_or_reexports(CRATE_DEF_ID.to_def_id());
+    visit::walk_crate(&mut link_resolver, krate);
+    link_resolver.process_extern_impls();
+
+    // FIXME: somehow rustdoc is still missing crates even though we loaded all
+    // the known necessary crates. Load them all unconditionally until we find a way to fix this.
+    // DO NOT REMOVE THIS without first testing on the reproducer in
+    // https://github.com/jyn514/objr/commit/edcee7b8124abf0e4c63873e8422ff81beb11ebb
+    for (extern_name, _) in externs.iter().filter(|(_, entry)| entry.add_prelude) {
+        link_resolver.resolver.resolve_rustdoc_path(extern_name, TypeNS, parent_scope);
+    }
+
+    ResolverCaches {
+        markdown_links: Some(link_resolver.markdown_links),
+        doc_link_resolutions: link_resolver.doc_link_resolutions,
+        traits_in_scope: link_resolver.traits_in_scope,
+        all_traits: Some(link_resolver.all_traits),
+        all_trait_impls: Some(link_resolver.all_trait_impls),
+        all_macro_rules: link_resolver.all_macro_rules,
+    }
+}
+
+fn doc_attrs<'a>(attrs: impl Iterator) -> Attributes {
+    Attributes::from_ast_iter(attrs.map(|attr| (attr, None)), true)
+}
+
+struct EarlyDocLinkResolver<'r, 'ra> {
+    resolver: &'r mut Resolver<'ra>,
+    sess: &'r Session,
+    parent_scope: ParentScope<'ra>,
+    visited_mods: DefIdSet,
+    markdown_links: FxHashMap>,
+    doc_link_resolutions: FxHashMap<(Symbol, Namespace, DefId), Option>>,
+    traits_in_scope: DefIdMap>,
+    all_traits: Vec,
+    all_trait_impls: Vec,
+    all_macro_rules: FxHashMap>,
+    document_private_items: bool,
+}
+
+impl<'ra> EarlyDocLinkResolver<'_, 'ra> {
+    fn add_traits_in_scope(&mut self, def_id: DefId) {
+        // Calls to `traits_in_scope` are expensive, so try to avoid them if only possible.
+        // Keys in the `traits_in_scope` cache are always module IDs.
+        if let Entry::Vacant(entry) = self.traits_in_scope.entry(def_id) {
+            let module = self.resolver.get_nearest_non_block_module(def_id);
+            let module_id = module.def_id();
+            let entry = if module_id == def_id {
+                Some(entry)
+            } else if let Entry::Vacant(entry) = self.traits_in_scope.entry(module_id) {
+                Some(entry)
+            } else {
+                None
+            };
+            if let Some(entry) = entry {
+                entry.insert(self.resolver.traits_in_scope(
+                    None,
+                    &ParentScope::module(module, self.resolver),
+                    SyntaxContext::root(),
+                    None,
+                ));
+            }
+        }
+    }
+
+    /// Add traits in scope for links in impls collected by the `collect-intra-doc-links` pass.
+    /// That pass filters impls using type-based information, but we don't yet have such
+    /// information here, so we just conservatively calculate traits in scope for *all* modules
+    /// having impls in them.
+    fn process_extern_impls(&mut self) {
+        // Resolving links in already existing crates may trigger loading of new crates.
+        let mut start_cnum = 0;
+        loop {
+            let crates = Vec::from_iter(self.resolver.cstore().crates_untracked());
+            for &cnum in &crates[start_cnum..] {
+                let all_traits =
+                    Vec::from_iter(self.resolver.cstore().traits_in_crate_untracked(cnum));
+                let all_trait_impls =
+                    Vec::from_iter(self.resolver.cstore().trait_impls_in_crate_untracked(cnum));
+                let all_inherent_impls =
+                    Vec::from_iter(self.resolver.cstore().inherent_impls_in_crate_untracked(cnum));
+                let all_incoherent_impls = Vec::from_iter(
+                    self.resolver.cstore().incoherent_impls_in_crate_untracked(cnum),
+                );
+
+                // Querying traits in scope is expensive so we try to prune the impl and traits lists
+                // using privacy, private traits and impls from other crates are never documented in
+                // the current crate, and links in their doc comments are not resolved.
+                for &def_id in &all_traits {
+                    if self.resolver.cstore().visibility_untracked(def_id).is_public() {
+                        self.resolve_doc_links_extern_impl(def_id, false);
+                    }
+                }
+                for &(trait_def_id, impl_def_id, simplified_self_ty) in &all_trait_impls {
+                    if self.resolver.cstore().visibility_untracked(trait_def_id).is_public()
+                        && simplified_self_ty.and_then(|ty| ty.def()).map_or(true, |ty_def_id| {
+                            self.resolver.cstore().visibility_untracked(ty_def_id).is_public()
+                        })
+                    {
+                        self.resolve_doc_links_extern_impl(impl_def_id, false);
+                    }
+                }
+                for (ty_def_id, impl_def_id) in all_inherent_impls {
+                    if self.resolver.cstore().visibility_untracked(ty_def_id).is_public() {
+                        self.resolve_doc_links_extern_impl(impl_def_id, true);
+                    }
+                }
+                for impl_def_id in all_incoherent_impls {
+                    self.resolve_doc_links_extern_impl(impl_def_id, true);
+                }
+
+                self.all_traits.extend(all_traits);
+                self.all_trait_impls
+                    .extend(all_trait_impls.into_iter().map(|(_, def_id, _)| def_id));
+            }
+
+            if crates.len() > start_cnum {
+                start_cnum = crates.len();
+            } else {
+                break;
+            }
+        }
+    }
+
+    fn resolve_doc_links_extern_impl(&mut self, def_id: DefId, is_inherent: bool) {
+        self.resolve_doc_links_extern_outer_fixme(def_id, def_id);
+        let assoc_item_def_ids = Vec::from_iter(
+            self.resolver.cstore().associated_item_def_ids_untracked(def_id, self.sess),
+        );
+        for assoc_def_id in assoc_item_def_ids {
+            if !is_inherent || self.resolver.cstore().visibility_untracked(assoc_def_id).is_public()
+            {
+                self.resolve_doc_links_extern_outer_fixme(assoc_def_id, def_id);
+            }
+        }
+    }
+
+    // FIXME: replace all uses with `resolve_doc_links_extern_outer` to actually resolve links, not
+    // just add traits in scope. This may be expensive and require benchmarking and optimization.
+    fn resolve_doc_links_extern_outer_fixme(&mut self, def_id: DefId, scope_id: DefId) {
+        if !self.resolver.cstore().may_have_doc_links_untracked(def_id) {
+            return;
+        }
+        if let Some(parent_id) = self.resolver.opt_parent(scope_id) {
+            self.add_traits_in_scope(parent_id);
+        }
+    }
+
+    fn resolve_doc_links_extern_outer(&mut self, def_id: DefId, scope_id: DefId) {
+        if !self.resolver.cstore().may_have_doc_links_untracked(def_id) {
+            return;
+        }
+        let attrs = Vec::from_iter(self.resolver.cstore().item_attrs_untracked(def_id, self.sess));
+        let parent_scope = ParentScope::module(
+            self.resolver.get_nearest_non_block_module(
+                self.resolver.opt_parent(scope_id).unwrap_or(scope_id),
+            ),
+            self.resolver,
+        );
+        self.resolve_doc_links(doc_attrs(attrs.iter()), parent_scope);
+    }
+
+    fn resolve_doc_links_extern_inner(&mut self, def_id: DefId) {
+        if !self.resolver.cstore().may_have_doc_links_untracked(def_id) {
+            return;
+        }
+        let attrs = Vec::from_iter(self.resolver.cstore().item_attrs_untracked(def_id, self.sess));
+        let parent_scope = ParentScope::module(self.resolver.expect_module(def_id), self.resolver);
+        self.resolve_doc_links(doc_attrs(attrs.iter()), parent_scope);
+    }
+
+    fn resolve_doc_links_local(&mut self, attrs: &[ast::Attribute]) {
+        if !attrs.iter().any(|attr| attr.may_have_doc_links()) {
+            return;
+        }
+        self.resolve_doc_links(doc_attrs(attrs.iter()), self.parent_scope);
+    }
+
+    fn resolve_and_cache(
+        &mut self,
+        path_str: &str,
+        ns: Namespace,
+        parent_scope: &ParentScope<'ra>,
+    ) -> bool {
+        // FIXME: This caching may be incorrect in case of multiple `macro_rules`
+        // items with the same name in the same module.
+        self.doc_link_resolutions
+            .entry((Symbol::intern(path_str), ns, parent_scope.module.def_id()))
+            .or_insert_with_key(|(path, ns, _)| {
+                self.resolver.resolve_rustdoc_path(path.as_str(), *ns, *parent_scope)
+            })
+            .is_some()
+    }
+
+    fn resolve_doc_links(&mut self, attrs: Attributes, parent_scope: ParentScope<'ra>) {
+        let mut need_traits_in_scope = false;
+        for (doc_module, doc) in attrs.prepare_to_doc_link_resolution() {
+            assert_eq!(doc_module, None);
+            let mut tmp_links = mem::take(&mut self.markdown_links);
+            let links =
+                tmp_links.entry(doc).or_insert_with_key(|doc| preprocessed_markdown_links(doc));
+            for PreprocessedMarkdownLink(pp_link, _) in links {
+                if let Ok(pinfo) = pp_link {
+                    // The logic here is a conservative approximation for path resolution in
+                    // `resolve_with_disambiguator`.
+                    if let Some(ns) = pinfo.disambiguator.map(Disambiguator::ns) {
+                        if self.resolve_and_cache(&pinfo.path_str, ns, &parent_scope) {
+                            continue;
+                        }
+                    }
+
+                    // Resolve all namespaces due to no disambiguator or for diagnostics.
+                    let mut any_resolved = false;
+                    let mut need_assoc = false;
+                    for ns in [TypeNS, ValueNS, MacroNS] {
+                        if self.resolve_and_cache(&pinfo.path_str, ns, &parent_scope) {
+                            any_resolved = true;
+                        } else if ns != MacroNS {
+                            need_assoc = true;
+                        }
+                    }
+
+                    // Resolve all prefixes for type-relative resolution or for diagnostics.
+                    if need_assoc || !any_resolved {
+                        let mut path = &pinfo.path_str[..];
+                        while let Some(idx) = path.rfind("::") {
+                            path = &path[..idx];
+                            need_traits_in_scope = true;
+                            for ns in [TypeNS, ValueNS, MacroNS] {
+                                self.resolve_and_cache(path, ns, &parent_scope);
+                            }
+                        }
+                    }
+                }
+            }
+            self.markdown_links = tmp_links;
+        }
+
+        if need_traits_in_scope {
+            self.add_traits_in_scope(parent_scope.module.def_id());
+        }
+    }
+
+    /// When reexports are inlined, they are replaced with item which they refer to, those items
+    /// may have links in their doc comments, those links are resolved at the item definition site,
+    /// so we need to know traits in scope at that definition site.
+    fn process_module_children_or_reexports(&mut self, module_id: DefId) {
+        if !self.visited_mods.insert(module_id) {
+            return; // avoid infinite recursion
+        }
+
+        for child in self.resolver.module_children_or_reexports(module_id) {
+            // This condition should give a superset of `denied` from `fn clean_use_statement`.
+            if child.vis.is_public()
+                || self.document_private_items
+                    && child.vis != Visibility::Restricted(module_id)
+                    && module_id.is_local()
+            {
+                if let Some(def_id) = child.res.opt_def_id() && !def_id.is_local() {
+                    let scope_id = match child.res {
+                        Res::Def(DefKind::Variant, ..) => self.resolver.parent(def_id),
+                        _ => def_id,
+                    };
+                    self.resolve_doc_links_extern_outer(def_id, scope_id); // Outer attribute scope
+                    if let Res::Def(DefKind::Mod, ..) = child.res {
+                        self.resolve_doc_links_extern_inner(def_id); // Inner attribute scope
+                    }
+                    // `DefKind::Trait`s are processed in `process_extern_impls`.
+                    if let Res::Def(DefKind::Mod | DefKind::Enum, ..) = child.res {
+                        self.process_module_children_or_reexports(def_id);
+                    }
+                    if let Res::Def(DefKind::Struct | DefKind::Union | DefKind::Variant, _) =
+                        child.res
+                    {
+                        let field_def_ids = Vec::from_iter(
+                            self.resolver
+                                .cstore()
+                                .associated_item_def_ids_untracked(def_id, self.sess),
+                        );
+                        for field_def_id in field_def_ids {
+                            self.resolve_doc_links_extern_outer(field_def_id, scope_id);
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
+
+impl Visitor<'_> for EarlyDocLinkResolver<'_, '_> {
+    fn visit_item(&mut self, item: &ast::Item) {
+        self.resolve_doc_links_local(&item.attrs); // Outer attribute scope
+        if let ItemKind::Mod(..) = item.kind {
+            let module_def_id = self.resolver.local_def_id(item.id).to_def_id();
+            let module = self.resolver.expect_module(module_def_id);
+            let old_module = mem::replace(&mut self.parent_scope.module, module);
+            let old_macro_rules = self.parent_scope.macro_rules;
+            self.resolve_doc_links_local(&item.attrs); // Inner attribute scope
+            self.process_module_children_or_reexports(module_def_id);
+            visit::walk_item(self, item);
+            if item
+                .attrs
+                .iter()
+                .all(|attr| !attr.has_name(sym::macro_use) && !attr.has_name(sym::macro_escape))
+            {
+                self.parent_scope.macro_rules = old_macro_rules;
+            }
+            self.parent_scope.module = old_module;
+        } else {
+            match &item.kind {
+                ItemKind::Trait(..) => {
+                    self.all_traits.push(self.resolver.local_def_id(item.id).to_def_id());
+                }
+                ItemKind::Impl(box ast::Impl { of_trait: Some(..), .. }) => {
+                    self.all_trait_impls.push(self.resolver.local_def_id(item.id).to_def_id());
+                }
+                ItemKind::MacroDef(macro_def) if macro_def.macro_rules => {
+                    let (macro_rules_scope, res) =
+                        self.resolver.macro_rules_scope(self.resolver.local_def_id(item.id));
+                    self.parent_scope.macro_rules = macro_rules_scope;
+                    self.all_macro_rules.insert(item.ident.name, res);
+                }
+                _ => {}
+            }
+            visit::walk_item(self, item);
+        }
+    }
+
+    fn visit_assoc_item(&mut self, item: &ast::AssocItem, ctxt: AssocCtxt) {
+        self.resolve_doc_links_local(&item.attrs);
+        visit::walk_assoc_item(self, item, ctxt)
+    }
+
+    fn visit_foreign_item(&mut self, item: &ast::ForeignItem) {
+        self.resolve_doc_links_local(&item.attrs);
+        visit::walk_foreign_item(self, item)
+    }
+
+    fn visit_variant(&mut self, v: &ast::Variant) {
+        self.resolve_doc_links_local(&v.attrs);
+        visit::walk_variant(self, v)
+    }
+
+    fn visit_field_def(&mut self, field: &ast::FieldDef) {
+        self.resolve_doc_links_local(&field.attrs);
+        visit::walk_field_def(self, field)
+    }
+
+    fn visit_block(&mut self, block: &ast::Block) {
+        let old_macro_rules = self.parent_scope.macro_rules;
+        visit::walk_block(self, block);
+        self.parent_scope.macro_rules = old_macro_rules;
+    }
+
+    // NOTE: if doc-comments are ever allowed on other nodes (e.g. function parameters),
+    // then this will have to implement other visitor methods too.
+}
diff --git a/src/librustdoc/passes/collect_trait_impls.rs b/src/librustdoc/passes/collect_trait_impls.rs
new file mode 100644
index 000000000..6b699c790
--- /dev/null
+++ b/src/librustdoc/passes/collect_trait_impls.rs
@@ -0,0 +1,273 @@
+//! Collects trait impls for each item in the crate. For example, if a crate
+//! defines a struct that implements a trait, this pass will note that the
+//! struct implements that trait.
+use super::Pass;
+use crate::clean::*;
+use crate::core::DocContext;
+use crate::formats::cache::Cache;
+use crate::visit::DocVisitor;
+
+use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_hir::def_id::DefId;
+use rustc_middle::ty::{self, DefIdTree};
+use rustc_span::symbol::sym;
+
+pub(crate) const COLLECT_TRAIT_IMPLS: Pass = Pass {
+    name: "collect-trait-impls",
+    run: collect_trait_impls,
+    description: "retrieves trait impls for items in the crate",
+};
+
+pub(crate) fn collect_trait_impls(mut krate: Crate, cx: &mut DocContext<'_>) -> Crate {
+    let synth_impls = cx.sess().time("collect_synthetic_impls", || {
+        let mut synth = SyntheticImplCollector { cx, impls: Vec::new() };
+        synth.visit_crate(&krate);
+        synth.impls
+    });
+
+    let prims: FxHashSet = krate.primitives.iter().map(|p| p.1).collect();
+
+    let crate_items = {
+        let mut coll = ItemCollector::new();
+        cx.sess().time("collect_items_for_trait_impls", || coll.visit_crate(&krate));
+        coll.items
+    };
+
+    let mut new_items_external = Vec::new();
+    let mut new_items_local = Vec::new();
+
+    // External trait impls.
+    cx.with_all_trait_impls(|cx, all_trait_impls| {
+        let _prof_timer = cx.tcx.sess.prof.generic_activity("build_extern_trait_impls");
+        for &impl_def_id in all_trait_impls.iter().skip_while(|def_id| def_id.is_local()) {
+            inline::build_impl(cx, None, impl_def_id, None, &mut new_items_external);
+        }
+    });
+
+    // Local trait impls.
+    cx.with_all_trait_impls(|cx, all_trait_impls| {
+        let _prof_timer = cx.tcx.sess.prof.generic_activity("build_local_trait_impls");
+        let mut attr_buf = Vec::new();
+        for &impl_def_id in all_trait_impls.iter().take_while(|def_id| def_id.is_local()) {
+            let mut parent = Some(cx.tcx.parent(impl_def_id));
+            while let Some(did) = parent {
+                attr_buf.extend(
+                    cx.tcx
+                        .get_attrs(did, sym::doc)
+                        .filter(|attr| {
+                            if let Some([attr]) = attr.meta_item_list().as_deref() {
+                                attr.has_name(sym::cfg)
+                            } else {
+                                false
+                            }
+                        })
+                        .cloned(),
+                );
+                parent = cx.tcx.opt_parent(did);
+            }
+            inline::build_impl(cx, None, impl_def_id, Some(&attr_buf), &mut new_items_local);
+            attr_buf.clear();
+        }
+    });
+
+    cx.tcx.sess.prof.generic_activity("build_primitive_trait_impls").run(|| {
+        for def_id in PrimitiveType::all_impls(cx.tcx) {
+            // Try to inline primitive impls from other crates.
+            if !def_id.is_local() {
+                inline::build_impl(cx, None, def_id, None, &mut new_items_external);
+            }
+        }
+        for (prim, did) in PrimitiveType::primitive_locations(cx.tcx) {
+            // Do not calculate blanket impl list for docs that are not going to be rendered.
+            // While the `impl` blocks themselves are only in `libcore`, the module with `doc`
+            // attached is directly included in `libstd` as well.
+            let tcx = cx.tcx;
+            if did.is_local() {
+                for def_id in prim.impls(tcx).filter(|def_id| {
+                    // Avoid including impl blocks with filled-in generics.
+                    // https://github.com/rust-lang/rust/issues/94937
+                    //
+                    // FIXME(notriddle): https://github.com/rust-lang/rust/issues/97129
+                    //
+                    // This tactic of using inherent impl blocks for getting
+                    // auto traits and blanket impls is a hack. What we really
+                    // want is to check if `[T]` impls `Send`, which has
+                    // nothing to do with the inherent impl.
+                    //
+                    // Rustdoc currently uses these `impl` block as a source of
+                    // the `Ty`, as well as the `ParamEnv`, `SubstsRef`, and
+                    // `Generics`. To avoid relying on the `impl` block, these
+                    // things would need to be created from wholecloth, in a
+                    // form that is valid for use in type inference.
+                    let ty = tcx.type_of(def_id);
+                    match ty.kind() {
+                        ty::Slice(ty)
+                        | ty::Ref(_, ty, _)
+                        | ty::RawPtr(ty::TypeAndMut { ty, .. }) => {
+                            matches!(ty.kind(), ty::Param(..))
+                        }
+                        ty::Tuple(tys) => tys.iter().all(|ty| matches!(ty.kind(), ty::Param(..))),
+                        _ => true,
+                    }
+                }) {
+                    let impls = get_auto_trait_and_blanket_impls(cx, def_id);
+                    new_items_external.extend(impls.filter(|i| cx.inlined.insert(i.item_id)));
+                }
+            }
+        }
+    });
+
+    let mut cleaner = BadImplStripper { prims, items: crate_items, cache: &cx.cache };
+    let mut type_did_to_deref_target: FxHashMap = FxHashMap::default();
+
+    // Follow all `Deref` targets of included items and recursively add them as valid
+    fn add_deref_target(
+        cx: &DocContext<'_>,
+        map: &FxHashMap,
+        cleaner: &mut BadImplStripper<'_>,
+        targets: &mut FxHashSet,
+        type_did: DefId,
+    ) {
+        if let Some(target) = map.get(&type_did) {
+            debug!("add_deref_target: type {:?}, target {:?}", type_did, target);
+            if let Some(target_prim) = target.primitive_type() {
+                cleaner.prims.insert(target_prim);
+            } else if let Some(target_did) = target.def_id(&cx.cache) {
+                // `impl Deref for S`
+                if !targets.insert(target_did) {
+                    // Avoid infinite cycles
+                    return;
+                }
+                cleaner.items.insert(target_did.into());
+                add_deref_target(cx, map, cleaner, targets, target_did);
+            }
+        }
+    }
+
+    // scan through included items ahead of time to splice in Deref targets to the "valid" sets
+    for it in new_items_external.iter().chain(new_items_local.iter()) {
+        if let ImplItem(box Impl { ref for_, ref trait_, ref items, .. }) = *it.kind {
+            if trait_.as_ref().map(|t| t.def_id()) == cx.tcx.lang_items().deref_trait()
+                && cleaner.keep_impl(for_, true)
+            {
+                let target = items
+                    .iter()
+                    .find_map(|item| match *item.kind {
+                        AssocTypeItem(ref t, _) => Some(&t.type_),
+                        _ => None,
+                    })
+                    .expect("Deref impl without Target type");
+
+                if let Some(prim) = target.primitive_type() {
+                    cleaner.prims.insert(prim);
+                } else if let Some(did) = target.def_id(&cx.cache) {
+                    cleaner.items.insert(did.into());
+                }
+                if let Some(for_did) = for_.def_id(&cx.cache) {
+                    if type_did_to_deref_target.insert(for_did, target).is_none() {
+                        // Since only the `DefId` portion of the `Type` instances is known to be same for both the
+                        // `Deref` target type and the impl for type positions, this map of types is keyed by
+                        // `DefId` and for convenience uses a special cleaner that accepts `DefId`s directly.
+                        if cleaner.keep_impl_with_def_id(for_did.into()) {
+                            let mut targets = FxHashSet::default();
+                            targets.insert(for_did);
+                            add_deref_target(
+                                cx,
+                                &type_did_to_deref_target,
+                                &mut cleaner,
+                                &mut targets,
+                                for_did,
+                            );
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    // Filter out external items that are not needed
+    new_items_external.retain(|it| {
+        if let ImplItem(box Impl { ref for_, ref trait_, ref kind, .. }) = *it.kind {
+            cleaner.keep_impl(
+                for_,
+                trait_.as_ref().map(|t| t.def_id()) == cx.tcx.lang_items().deref_trait(),
+            ) || trait_.as_ref().map_or(false, |t| cleaner.keep_impl_with_def_id(t.def_id().into()))
+                || kind.is_blanket()
+        } else {
+            true
+        }
+    });
+
+    if let ModuleItem(Module { items, .. }) = &mut *krate.module.kind {
+        items.extend(synth_impls);
+        items.extend(new_items_external);
+        items.extend(new_items_local);
+    } else {
+        panic!("collect-trait-impls can't run");
+    };
+
+    krate
+}
+
+struct SyntheticImplCollector<'a, 'tcx> {
+    cx: &'a mut DocContext<'tcx>,
+    impls: Vec,
+}
+
+impl<'a, 'tcx> DocVisitor for SyntheticImplCollector<'a, 'tcx> {
+    fn visit_item(&mut self, i: &Item) {
+        if i.is_struct() || i.is_enum() || i.is_union() {
+            // FIXME(eddyb) is this `doc(hidden)` check needed?
+            if !self.cx.tcx.is_doc_hidden(i.item_id.expect_def_id()) {
+                self.impls
+                    .extend(get_auto_trait_and_blanket_impls(self.cx, i.item_id.expect_def_id()));
+            }
+        }
+
+        self.visit_item_recur(i)
+    }
+}
+
+#[derive(Default)]
+struct ItemCollector {
+    items: FxHashSet,
+}
+
+impl ItemCollector {
+    fn new() -> Self {
+        Self::default()
+    }
+}
+
+impl DocVisitor for ItemCollector {
+    fn visit_item(&mut self, i: &Item) {
+        self.items.insert(i.item_id);
+
+        self.visit_item_recur(i)
+    }
+}
+
+struct BadImplStripper<'a> {
+    prims: FxHashSet,
+    items: FxHashSet,
+    cache: &'a Cache,
+}
+
+impl<'a> BadImplStripper<'a> {
+    fn keep_impl(&self, ty: &Type, is_deref: bool) -> bool {
+        if let Generic(_) = ty {
+            // keep impls made on generics
+            true
+        } else if let Some(prim) = ty.primitive_type() {
+            self.prims.contains(&prim)
+        } else if let Some(did) = ty.def_id(self.cache) {
+            is_deref || self.keep_impl_with_def_id(did.into())
+        } else {
+            false
+        }
+    }
+
+    fn keep_impl_with_def_id(&self, item_id: ItemId) -> bool {
+        self.items.contains(&item_id)
+    }
+}
diff --git a/src/librustdoc/passes/html_tags.rs b/src/librustdoc/passes/html_tags.rs
new file mode 100644
index 000000000..f3a3c853c
--- /dev/null
+++ b/src/librustdoc/passes/html_tags.rs
@@ -0,0 +1,303 @@
+//! Detects invalid HTML (like an unclosed ``) in doc comments.
+use super::Pass;
+use crate::clean::*;
+use crate::core::DocContext;
+use crate::html::markdown::main_body_opts;
+use crate::visit::DocVisitor;
+
+use pulldown_cmark::{BrokenLink, Event, LinkType, Parser, Tag};
+
+use std::iter::Peekable;
+use std::ops::Range;
+use std::str::CharIndices;
+
+pub(crate) const CHECK_INVALID_HTML_TAGS: Pass = Pass {
+    name: "check-invalid-html-tags",
+    run: check_invalid_html_tags,
+    description: "detects invalid HTML tags in doc comments",
+};
+
+struct InvalidHtmlTagsLinter<'a, 'tcx> {
+    cx: &'a mut DocContext<'tcx>,
+}
+
+pub(crate) fn check_invalid_html_tags(krate: Crate, cx: &mut DocContext<'_>) -> Crate {
+    if cx.tcx.sess.is_nightly_build() {
+        let mut coll = InvalidHtmlTagsLinter { cx };
+        coll.visit_crate(&krate);
+    }
+    krate
+}
+
+const ALLOWED_UNCLOSED: &[&str] = &[
+    "area", "base", "br", "col", "embed", "hr", "img", "input", "keygen", "link", "meta", "param",
+    "source", "track", "wbr",
+];
+
+fn drop_tag(
+    tags: &mut Vec<(String, Range)>,
+    tag_name: String,
+    range: Range,
+    f: &impl Fn(&str, &Range, bool),
+) {
+    let tag_name_low = tag_name.to_lowercase();
+    if let Some(pos) = tags.iter().rposition(|(t, _)| t.to_lowercase() == tag_name_low) {
+        // If the tag is nested inside a "` (the `h2` tag isn't required
+        // but it helps for the visualization).
+        f(&format!("unopened HTML tag `{}`", tag_name), &range, false);
+    }
+}
+
+fn extract_path_backwards(text: &str, end_pos: usize) -> Option {
+    use rustc_lexer::{is_id_continue, is_id_start};
+    let mut current_pos = end_pos;
+    loop {
+        if current_pos >= 2 && text[..current_pos].ends_with("::") {
+            current_pos -= 2;
+        }
+        let new_pos = text[..current_pos]
+            .char_indices()
+            .rev()
+            .take_while(|(_, c)| is_id_start(*c) || is_id_continue(*c))
+            .reduce(|_accum, item| item)
+            .and_then(|(new_pos, c)| is_id_start(c).then_some(new_pos));
+        if let Some(new_pos) = new_pos {
+            if current_pos != new_pos {
+                current_pos = new_pos;
+                continue;
+            }
+        }
+        break;
+    }
+    if current_pos == end_pos { None } else { Some(current_pos) }
+}
+
+fn is_valid_for_html_tag_name(c: char, is_empty: bool) -> bool {
+    // https://spec.commonmark.org/0.30/#raw-html
+    //
+    // > A tag name consists of an ASCII letter followed by zero or more ASCII letters, digits, or
+    // > hyphens (-).
+    c.is_ascii_alphabetic() || !is_empty && (c == '-' || c.is_ascii_digit())
+}
+
+fn extract_html_tag(
+    tags: &mut Vec<(String, Range)>,
+    text: &str,
+    range: &Range,
+    start_pos: usize,
+    iter: &mut Peekable>,
+    f: &impl Fn(&str, &Range, bool),
+) {
+    let mut tag_name = String::new();
+    let mut is_closing = false;
+    let mut prev_pos = start_pos;
+
+    loop {
+        let (pos, c) = match iter.peek() {
+            Some((pos, c)) => (*pos, *c),
+            // In case we reached the of the doc comment, we want to check that it's an
+            // unclosed HTML tag. For example "///  (prev_pos, '\0'),
+        };
+        prev_pos = pos;
+        // Checking if this is a closing tag (like `` for ``).
+        if c == '/' && tag_name.is_empty() {
+            is_closing = true;
+        } else if is_valid_for_html_tag_name(c, tag_name.is_empty()) {
+            tag_name.push(c);
+        } else {
+            if !tag_name.is_empty() {
+                let mut r = Range { start: range.start + start_pos, end: range.start + pos };
+                if c == '>' {
+                    // In case we have a tag without attribute, we can consider the span to
+                    // refer to it fully.
+                    r.end += 1;
+                }
+                if is_closing {
+                    // In case we have "" or even "".
+                    if c != '>' {
+                        if !c.is_whitespace() {
+                            // It seems like it's not a valid HTML tag.
+                            break;
+                        }
+                        let mut found = false;
+                        for (new_pos, c) in text[pos..].char_indices() {
+                            if !c.is_whitespace() {
+                                if c == '>' {
+                                    r.end = range.start + new_pos + 1;
+                                    found = true;
+                                }
+                                break;
+                            }
+                        }
+                        if !found {
+                            break;
+                        }
+                    }
+                    drop_tag(tags, tag_name, r, f);
+                } else {
+                    tags.push((tag_name, r));
+                }
+            }
+            break;
+        }
+        iter.next();
+    }
+}
+
+fn extract_tags(
+    tags: &mut Vec<(String, Range)>,
+    text: &str,
+    range: Range,
+    is_in_comment: &mut Option>,
+    f: &impl Fn(&str, &Range, bool),
+) {
+    let mut iter = text.char_indices().peekable();
+
+    while let Some((start_pos, c)) = iter.next() {
+        if is_in_comment.is_some() {
+            if text[start_pos..].starts_with("-->") {
+                *is_in_comment = None;
+            }
+        } else if c == '<' {
+            if text[start_pos..].starts_with("