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/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 | 395 +++ .../html/static/fonts/FiraSans-LICENSE.txt | 94 + .../html/static/fonts/FiraSans-Medium.woff2 | Bin 0 -> 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src/librustdoc/html/static/images/favicon.svg | 24 + src/librustdoc/html/static/images/rust-logo.svg | 61 + src/librustdoc/html/static/images/toggle-minus.svg | 1 + src/librustdoc/html/static/images/toggle-plus.svg | 1 + src/librustdoc/html/static/images/wheel.svg | 1 + src/librustdoc/html/static/js/README.md | 15 + src/librustdoc/html/static/js/externs.js | 142 + src/librustdoc/html/static/js/main.js | 974 +++++++ src/librustdoc/html/static/js/scrape-examples.js | 106 + src/librustdoc/html/static/js/search.js | 2297 ++++++++++++++++ src/librustdoc/html/static/js/settings.js | 272 ++ src/librustdoc/html/static/js/source-script.js | 241 ++ src/librustdoc/html/static/js/storage.js | 268 ++ src/librustdoc/html/static/scrape-examples-help.md | 34 + src/librustdoc/html/static_files.rs | 168 ++ src/librustdoc/html/templates/STYLE.md | 37 + 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 + 76 files changed, 22160 insertions(+) create mode 100644 src/librustdoc/html/escape.rs create mode 100644 src/librustdoc/html/format.rs create mode 100644 src/librustdoc/html/highlight.rs create mode 100644 src/librustdoc/html/highlight/fixtures/decorations.html create mode 100644 src/librustdoc/html/highlight/fixtures/dos_line.html create mode 100644 src/librustdoc/html/highlight/fixtures/highlight.html create mode 100644 src/librustdoc/html/highlight/fixtures/sample.html create mode 100644 src/librustdoc/html/highlight/fixtures/sample.rs create mode 100644 src/librustdoc/html/highlight/fixtures/union.html create mode 100644 src/librustdoc/html/highlight/fixtures/union.rs create mode 100644 src/librustdoc/html/highlight/tests.rs create mode 100644 src/librustdoc/html/layout.rs create mode 100644 src/librustdoc/html/length_limit.rs create mode 100644 src/librustdoc/html/length_limit/tests.rs create mode 100644 src/librustdoc/html/markdown.rs create mode 100644 src/librustdoc/html/markdown/tests.rs create mode 100644 src/librustdoc/html/mod.rs create mode 100644 src/librustdoc/html/render/context.rs create mode 100644 src/librustdoc/html/render/mod.rs create mode 100644 src/librustdoc/html/render/print_item.rs create mode 100644 src/librustdoc/html/render/search_index.rs create mode 100644 src/librustdoc/html/render/span_map.rs create mode 100644 src/librustdoc/html/render/tests.rs create mode 100644 src/librustdoc/html/render/write_shared.rs create mode 100644 src/librustdoc/html/sources.rs create mode 100644 src/librustdoc/html/static/.eslintrc.js create mode 100644 src/librustdoc/html/static/COPYRIGHT.txt create mode 100644 src/librustdoc/html/static/LICENSE-APACHE.txt create mode 100644 src/librustdoc/html/static/LICENSE-MIT.txt create mode 100644 src/librustdoc/html/static/css/normalize.css create mode 100644 src/librustdoc/html/static/css/noscript.css create mode 100644 src/librustdoc/html/static/css/rustdoc.css create mode 100644 src/librustdoc/html/static/css/settings.css create mode 100644 src/librustdoc/html/static/css/themes/ayu.css create mode 100644 src/librustdoc/html/static/css/themes/dark.css create mode 100644 src/librustdoc/html/static/css/themes/light.css create mode 100644 src/librustdoc/html/static/fonts/FiraSans-LICENSE.txt create mode 100644 src/librustdoc/html/static/fonts/FiraSans-Medium.woff2 create mode 100644 src/librustdoc/html/static/fonts/FiraSans-Regular.woff2 create mode 100644 src/librustdoc/html/static/fonts/NanumBarunGothic-LICENSE.txt create mode 100644 src/librustdoc/html/static/fonts/NanumBarunGothic.ttf.woff2 create mode 100644 src/librustdoc/html/static/fonts/SourceCodePro-It.ttf.woff2 create mode 100644 src/librustdoc/html/static/fonts/SourceCodePro-LICENSE.txt create mode 100644 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src/librustdoc/html/static/images/toggle-plus.svg create mode 100644 src/librustdoc/html/static/images/wheel.svg create mode 100644 src/librustdoc/html/static/js/README.md create mode 100644 src/librustdoc/html/static/js/externs.js create mode 100644 src/librustdoc/html/static/js/main.js create mode 100644 src/librustdoc/html/static/js/scrape-examples.js create mode 100644 src/librustdoc/html/static/js/search.js create mode 100644 src/librustdoc/html/static/js/settings.js create mode 100644 src/librustdoc/html/static/js/source-script.js create mode 100644 src/librustdoc/html/static/js/storage.js create mode 100644 src/librustdoc/html/static/scrape-examples-help.md create mode 100644 src/librustdoc/html/static_files.rs create mode 100644 src/librustdoc/html/templates/STYLE.md create mode 100644 src/librustdoc/html/templates/page.html create mode 100644 src/librustdoc/html/templates/print_item.html create mode 100644 src/librustdoc/html/tests.rs create mode 100644 src/librustdoc/html/toc.rs create mode 100644 src/librustdoc/html/toc/tests.rs create mode 100644 src/librustdoc/html/url_parts_builder.rs create mode 100644 src/librustdoc/html/url_parts_builder/tests.rs (limited to 'src/librustdoc/html') 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");
+}
-- 
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