use crate::hir::{ModuleItems, Owner}; use crate::ty::{DefIdTree, TyCtxt}; use rustc_ast as ast; use rustc_data_structures::fingerprint::Fingerprint; use rustc_data_structures::stable_hasher::{HashStable, StableHasher}; use rustc_data_structures::svh::Svh; use rustc_data_structures::sync::{par_for_each_in, Send, Sync}; use rustc_hir::def::{DefKind, Res}; use rustc_hir::def_id::{CrateNum, DefId, LocalDefId, CRATE_DEF_ID, LOCAL_CRATE}; use rustc_hir::definitions::{DefKey, DefPath, DefPathHash}; use rustc_hir::intravisit::{self, Visitor}; use rustc_hir::*; use rustc_index::vec::Idx; use rustc_middle::hir::nested_filter; use rustc_span::def_id::StableCrateId; use rustc_span::symbol::{kw, sym, Ident, Symbol}; use rustc_span::{Span, DUMMY_SP}; use rustc_target::spec::abi::Abi; #[inline] pub fn associated_body<'hir>(node: Node<'hir>) -> Option { match node { Node::Item(Item { kind: ItemKind::Const(_, body) | ItemKind::Static(.., body) | ItemKind::Fn(.., body), .. }) | Node::TraitItem(TraitItem { kind: TraitItemKind::Const(_, Some(body)) | TraitItemKind::Fn(_, TraitFn::Provided(body)), .. }) | Node::ImplItem(ImplItem { kind: ImplItemKind::Const(_, body) | ImplItemKind::Fn(_, body), .. }) | Node::Expr(Expr { kind: ExprKind::Closure(Closure { body, .. }), .. }) => Some(*body), Node::AnonConst(constant) => Some(constant.body), _ => None, } } fn is_body_owner<'hir>(node: Node<'hir>, hir_id: HirId) -> bool { match associated_body(node) { Some(b) => b.hir_id == hir_id, None => false, } } #[derive(Copy, Clone)] pub struct Map<'hir> { pub(super) tcx: TyCtxt<'hir>, } /// An iterator that walks up the ancestor tree of a given `HirId`. /// Constructed using `tcx.hir().parent_iter(hir_id)`. pub struct ParentHirIterator<'hir> { current_id: HirId, map: Map<'hir>, } impl<'hir> Iterator for ParentHirIterator<'hir> { type Item = HirId; fn next(&mut self) -> Option { if self.current_id == CRATE_HIR_ID { return None; } loop { // There are nodes that do not have entries, so we need to skip them. let parent_id = self.map.get_parent_node(self.current_id); if parent_id == self.current_id { self.current_id = CRATE_HIR_ID; return None; } self.current_id = parent_id; return Some(parent_id); } } } /// An iterator that walks up the ancestor tree of a given `HirId`. /// Constructed using `tcx.hir().parent_owner_iter(hir_id)`. pub struct ParentOwnerIterator<'hir> { current_id: HirId, map: Map<'hir>, } impl<'hir> Iterator for ParentOwnerIterator<'hir> { type Item = (OwnerId, OwnerNode<'hir>); fn next(&mut self) -> Option { if self.current_id.local_id.index() != 0 { self.current_id.local_id = ItemLocalId::new(0); if let Some(node) = self.map.tcx.hir_owner(self.current_id.owner) { return Some((self.current_id.owner, node.node)); } } if self.current_id == CRATE_HIR_ID { return None; } loop { // There are nodes that do not have entries, so we need to skip them. let parent_id = self.map.def_key(self.current_id.owner.def_id).parent; let parent_id = parent_id.map_or(CRATE_OWNER_ID, |local_def_index| { let def_id = LocalDefId { local_def_index }; self.map.local_def_id_to_hir_id(def_id).owner }); self.current_id = HirId::make_owner(parent_id.def_id); // If this `HirId` doesn't have an entry, skip it and look for its `parent_id`. if let Some(node) = self.map.tcx.hir_owner(self.current_id.owner) { return Some((self.current_id.owner, node.node)); } } } } impl<'hir> Map<'hir> { #[inline] pub fn krate(self) -> &'hir Crate<'hir> { self.tcx.hir_crate(()) } #[inline] pub fn root_module(self) -> &'hir Mod<'hir> { match self.tcx.hir_owner(CRATE_OWNER_ID).map(|o| o.node) { Some(OwnerNode::Crate(item)) => item, _ => bug!(), } } #[inline] pub fn items(self) -> impl Iterator + 'hir { self.tcx.hir_crate_items(()).items.iter().copied() } #[inline] pub fn module_items(self, module: LocalDefId) -> impl Iterator + 'hir { self.tcx.hir_module_items(module).items() } #[inline] pub fn par_for_each_item(self, f: impl Fn(ItemId) + Sync + Send) { par_for_each_in(&self.tcx.hir_crate_items(()).items[..], |id| f(*id)); } pub fn def_key(self, def_id: LocalDefId) -> DefKey { // Accessing the DefKey is ok, since it is part of DefPathHash. self.tcx.definitions_untracked().def_key(def_id) } pub fn def_path_from_hir_id(self, id: HirId) -> Option { self.opt_local_def_id(id).map(|def_id| self.def_path(def_id)) } pub fn def_path(self, def_id: LocalDefId) -> DefPath { // Accessing the DefPath is ok, since it is part of DefPathHash. self.tcx.definitions_untracked().def_path(def_id) } #[inline] pub fn def_path_hash(self, def_id: LocalDefId) -> DefPathHash { // Accessing the DefPathHash is ok, it is incr. comp. stable. self.tcx.definitions_untracked().def_path_hash(def_id) } #[inline] pub fn local_def_id(self, hir_id: HirId) -> LocalDefId { self.opt_local_def_id(hir_id).unwrap_or_else(|| { bug!( "local_def_id: no entry for `{:?}`, which has a map of `{:?}`", hir_id, self.find(hir_id) ) }) } #[inline] pub fn opt_local_def_id(self, hir_id: HirId) -> Option { if hir_id.local_id == ItemLocalId::new(0) { Some(hir_id.owner.def_id) } else { self.tcx .hir_owner_nodes(hir_id.owner) .as_owner()? .local_id_to_def_id .get(&hir_id.local_id) .copied() } } #[inline] pub fn local_def_id_to_hir_id(self, def_id: LocalDefId) -> HirId { self.tcx.local_def_id_to_hir_id(def_id) } /// Do not call this function directly. The query should be called. pub(super) fn opt_def_kind(self, local_def_id: LocalDefId) -> Option { let hir_id = self.local_def_id_to_hir_id(local_def_id); let def_kind = match self.find(hir_id)? { Node::Item(item) => match item.kind { ItemKind::Static(_, mt, _) => DefKind::Static(mt), ItemKind::Const(..) => DefKind::Const, ItemKind::Fn(..) => DefKind::Fn, ItemKind::Macro(_, macro_kind) => DefKind::Macro(macro_kind), ItemKind::Mod(..) => DefKind::Mod, ItemKind::OpaqueTy(ref opaque) => { if opaque.in_trait { DefKind::ImplTraitPlaceholder } else { DefKind::OpaqueTy } } ItemKind::TyAlias(..) => DefKind::TyAlias, ItemKind::Enum(..) => DefKind::Enum, ItemKind::Struct(..) => DefKind::Struct, ItemKind::Union(..) => DefKind::Union, ItemKind::Trait(..) => DefKind::Trait, ItemKind::TraitAlias(..) => DefKind::TraitAlias, ItemKind::ExternCrate(_) => DefKind::ExternCrate, ItemKind::Use(..) => DefKind::Use, ItemKind::ForeignMod { .. } => DefKind::ForeignMod, ItemKind::GlobalAsm(..) => DefKind::GlobalAsm, ItemKind::Impl { .. } => DefKind::Impl, }, Node::ForeignItem(item) => match item.kind { ForeignItemKind::Fn(..) => DefKind::Fn, ForeignItemKind::Static(_, mt) => DefKind::Static(mt), ForeignItemKind::Type => DefKind::ForeignTy, }, Node::TraitItem(item) => match item.kind { TraitItemKind::Const(..) => DefKind::AssocConst, TraitItemKind::Fn(..) => DefKind::AssocFn, TraitItemKind::Type(..) => DefKind::AssocTy, }, Node::ImplItem(item) => match item.kind { ImplItemKind::Const(..) => DefKind::AssocConst, ImplItemKind::Fn(..) => DefKind::AssocFn, ImplItemKind::Type(..) => DefKind::AssocTy, }, Node::Variant(_) => DefKind::Variant, Node::Ctor(variant_data) => { // FIXME(eddyb) is this even possible, if we have a `Node::Ctor`? assert_ne!(variant_data.ctor_hir_id(), None); let ctor_of = match self.find(self.get_parent_node(hir_id)) { Some(Node::Item(..)) => def::CtorOf::Struct, Some(Node::Variant(..)) => def::CtorOf::Variant, _ => unreachable!(), }; DefKind::Ctor(ctor_of, def::CtorKind::from_hir(variant_data)) } Node::AnonConst(_) => { let inline = match self.find(self.get_parent_node(hir_id)) { Some(Node::Expr(&Expr { kind: ExprKind::ConstBlock(ref anon_const), .. })) if anon_const.hir_id == hir_id => true, _ => false, }; if inline { DefKind::InlineConst } else { DefKind::AnonConst } } Node::Field(_) => DefKind::Field, Node::Expr(expr) => match expr.kind { ExprKind::Closure(Closure { movability: None, .. }) => DefKind::Closure, ExprKind::Closure(Closure { movability: Some(_), .. }) => DefKind::Generator, _ => bug!("def_kind: unsupported node: {}", self.node_to_string(hir_id)), }, Node::GenericParam(param) => match param.kind { GenericParamKind::Lifetime { .. } => DefKind::LifetimeParam, GenericParamKind::Type { .. } => DefKind::TyParam, GenericParamKind::Const { .. } => DefKind::ConstParam, }, Node::Crate(_) => DefKind::Mod, Node::Stmt(_) | Node::PathSegment(_) | Node::Ty(_) | Node::TypeBinding(_) | Node::Infer(_) | Node::TraitRef(_) | Node::Pat(_) | Node::PatField(_) | Node::ExprField(_) | Node::Local(_) | Node::Param(_) | Node::Arm(_) | Node::Lifetime(_) | Node::Block(_) => return None, }; Some(def_kind) } /// Finds the id of the parent node to this one. /// /// If calling repeatedly and iterating over parents, prefer [`Map::parent_iter`]. pub fn find_parent_node(self, id: HirId) -> Option { if id.local_id == ItemLocalId::from_u32(0) { Some(self.tcx.hir_owner_parent(id.owner)) } else { let owner = self.tcx.hir_owner_nodes(id.owner).as_owner()?; let node = owner.nodes[id.local_id].as_ref()?; let hir_id = HirId { owner: id.owner, local_id: node.parent }; // HIR indexing should have checked that. debug_assert_ne!(id.local_id, node.parent); Some(hir_id) } } pub fn get_parent_node(self, hir_id: HirId) -> HirId { self.find_parent_node(hir_id) .unwrap_or_else(|| bug!("No parent for node {:?}", self.node_to_string(hir_id))) } /// Retrieves the `Node` corresponding to `id`, returning `None` if cannot be found. pub fn find(self, id: HirId) -> Option> { if id.local_id == ItemLocalId::from_u32(0) { let owner = self.tcx.hir_owner(id.owner)?; Some(owner.node.into()) } else { let owner = self.tcx.hir_owner_nodes(id.owner).as_owner()?; let node = owner.nodes[id.local_id].as_ref()?; Some(node.node) } } /// Retrieves the `Node` corresponding to `id`, returning `None` if cannot be found. #[inline] pub fn find_by_def_id(self, id: LocalDefId) -> Option> { self.find(self.local_def_id_to_hir_id(id)) } /// Retrieves the `Node` corresponding to `id`, panicking if it cannot be found. pub fn get(self, id: HirId) -> Node<'hir> { self.find(id).unwrap_or_else(|| bug!("couldn't find hir id {} in the HIR map", id)) } /// Retrieves the `Node` corresponding to `id`, panicking if it cannot be found. #[inline] pub fn get_by_def_id(self, id: LocalDefId) -> Node<'hir> { self.find_by_def_id(id).unwrap_or_else(|| bug!("couldn't find {:?} in the HIR map", id)) } pub fn get_if_local(self, id: DefId) -> Option> { id.as_local().and_then(|id| self.find(self.local_def_id_to_hir_id(id))) } pub fn get_generics(self, id: LocalDefId) -> Option<&'hir Generics<'hir>> { let node = self.tcx.hir_owner(OwnerId { def_id: id })?; node.node.generics() } pub fn item(self, id: ItemId) -> &'hir Item<'hir> { self.tcx.hir_owner(id.owner_id).unwrap().node.expect_item() } pub fn trait_item(self, id: TraitItemId) -> &'hir TraitItem<'hir> { self.tcx.hir_owner(id.owner_id).unwrap().node.expect_trait_item() } pub fn impl_item(self, id: ImplItemId) -> &'hir ImplItem<'hir> { self.tcx.hir_owner(id.owner_id).unwrap().node.expect_impl_item() } pub fn foreign_item(self, id: ForeignItemId) -> &'hir ForeignItem<'hir> { self.tcx.hir_owner(id.owner_id).unwrap().node.expect_foreign_item() } pub fn body(self, id: BodyId) -> &'hir Body<'hir> { self.tcx.hir_owner_nodes(id.hir_id.owner).unwrap().bodies[&id.hir_id.local_id] } pub fn fn_decl_by_hir_id(self, hir_id: HirId) -> Option<&'hir FnDecl<'hir>> { if let Some(node) = self.find(hir_id) { node.fn_decl() } else { bug!("no node for hir_id `{}`", hir_id) } } pub fn fn_sig_by_hir_id(self, hir_id: HirId) -> Option<&'hir FnSig<'hir>> { if let Some(node) = self.find(hir_id) { node.fn_sig() } else { bug!("no node for hir_id `{}`", hir_id) } } pub fn enclosing_body_owner(self, hir_id: HirId) -> LocalDefId { for (_, node) in self.parent_iter(hir_id) { if let Some(body) = associated_body(node) { return self.body_owner_def_id(body); } } bug!("no `enclosing_body_owner` for hir_id `{}`", hir_id); } /// Returns the `HirId` that corresponds to the definition of /// which this is the body of, i.e., a `fn`, `const` or `static` /// item (possibly associated), a closure, or a `hir::AnonConst`. pub fn body_owner(self, BodyId { hir_id }: BodyId) -> HirId { let parent = self.get_parent_node(hir_id); assert!(self.find(parent).map_or(false, |n| is_body_owner(n, hir_id))); parent } pub fn body_owner_def_id(self, id: BodyId) -> LocalDefId { self.local_def_id(self.body_owner(id)) } /// Given a `LocalDefId`, returns the `BodyId` associated with it, /// if the node is a body owner, otherwise returns `None`. pub fn maybe_body_owned_by(self, id: LocalDefId) -> Option { self.get_if_local(id.to_def_id()).map(associated_body).flatten() } /// Given a body owner's id, returns the `BodyId` associated with it. pub fn body_owned_by(self, id: LocalDefId) -> BodyId { self.maybe_body_owned_by(id).unwrap_or_else(|| { let hir_id = self.local_def_id_to_hir_id(id); span_bug!( self.span(hir_id), "body_owned_by: {} has no associated body", self.node_to_string(hir_id) ); }) } pub fn body_param_names(self, id: BodyId) -> impl Iterator + 'hir { self.body(id).params.iter().map(|arg| match arg.pat.kind { PatKind::Binding(_, _, ident, _) => ident, _ => Ident::empty(), }) } /// Returns the `BodyOwnerKind` of this `LocalDefId`. /// /// Panics if `LocalDefId` does not have an associated body. pub fn body_owner_kind(self, def_id: LocalDefId) -> BodyOwnerKind { match self.tcx.def_kind(def_id) { DefKind::Const | DefKind::AssocConst | DefKind::InlineConst | DefKind::AnonConst => { BodyOwnerKind::Const } DefKind::Ctor(..) | DefKind::Fn | DefKind::AssocFn => BodyOwnerKind::Fn, DefKind::Closure | DefKind::Generator => BodyOwnerKind::Closure, DefKind::Static(mt) => BodyOwnerKind::Static(mt), dk => bug!("{:?} is not a body node: {:?}", def_id, dk), } } /// Returns the `ConstContext` of the body associated with this `LocalDefId`. /// /// Panics if `LocalDefId` does not have an associated body. /// /// This should only be used for determining the context of a body, a return /// value of `Some` does not always suggest that the owner of the body is `const`, /// just that it has to be checked as if it were. pub fn body_const_context(self, def_id: LocalDefId) -> Option { let ccx = match self.body_owner_kind(def_id) { BodyOwnerKind::Const => ConstContext::Const, BodyOwnerKind::Static(mt) => ConstContext::Static(mt), BodyOwnerKind::Fn if self.tcx.is_constructor(def_id.to_def_id()) => return None, BodyOwnerKind::Fn if self.tcx.is_const_fn_raw(def_id.to_def_id()) => { ConstContext::ConstFn } BodyOwnerKind::Fn if self.tcx.is_const_default_method(def_id.to_def_id()) => { ConstContext::ConstFn } BodyOwnerKind::Fn | BodyOwnerKind::Closure => return None, }; Some(ccx) } /// Returns an iterator of the `DefId`s for all body-owners in this /// crate. If you would prefer to iterate over the bodies /// themselves, you can do `self.hir().krate().body_ids.iter()`. #[inline] pub fn body_owners(self) -> impl Iterator + 'hir { self.tcx.hir_crate_items(()).body_owners.iter().copied() } #[inline] pub fn par_body_owners(self, f: impl Fn(LocalDefId) + Sync + Send) { par_for_each_in(&self.tcx.hir_crate_items(()).body_owners[..], |&def_id| f(def_id)); } pub fn ty_param_owner(self, def_id: LocalDefId) -> LocalDefId { let def_kind = self.tcx.def_kind(def_id); match def_kind { DefKind::Trait | DefKind::TraitAlias => def_id, DefKind::LifetimeParam | DefKind::TyParam | DefKind::ConstParam => { self.tcx.local_parent(def_id) } _ => bug!("ty_param_owner: {:?} is a {:?} not a type parameter", def_id, def_kind), } } pub fn ty_param_name(self, def_id: LocalDefId) -> Symbol { let def_kind = self.tcx.def_kind(def_id); match def_kind { DefKind::Trait | DefKind::TraitAlias => kw::SelfUpper, DefKind::LifetimeParam | DefKind::TyParam | DefKind::ConstParam => { self.tcx.item_name(def_id.to_def_id()) } _ => bug!("ty_param_name: {:?} is a {:?} not a type parameter", def_id, def_kind), } } pub fn trait_impls(self, trait_did: DefId) -> &'hir [LocalDefId] { self.tcx.all_local_trait_impls(()).get(&trait_did).map_or(&[], |xs| &xs[..]) } /// Gets the attributes on the crate. This is preferable to /// invoking `krate.attrs` because it registers a tighter /// dep-graph access. pub fn krate_attrs(self) -> &'hir [ast::Attribute] { self.attrs(CRATE_HIR_ID) } pub fn rustc_coherence_is_core(self) -> bool { self.krate_attrs().iter().any(|attr| attr.has_name(sym::rustc_coherence_is_core)) } pub fn get_module(self, module: LocalDefId) -> (&'hir Mod<'hir>, Span, HirId) { let hir_id = HirId::make_owner(module); match self.tcx.hir_owner(hir_id.owner).map(|o| o.node) { Some(OwnerNode::Item(&Item { span, kind: ItemKind::Mod(ref m), .. })) => { (m, span, hir_id) } Some(OwnerNode::Crate(item)) => (item, item.spans.inner_span, hir_id), node => panic!("not a module: {:?}", node), } } /// Walks the contents of the local crate. See also `visit_all_item_likes_in_crate`. pub fn walk_toplevel_module(self, visitor: &mut impl Visitor<'hir>) { let (top_mod, span, hir_id) = self.get_module(CRATE_DEF_ID); visitor.visit_mod(top_mod, span, hir_id); } /// Walks the attributes in a crate. pub fn walk_attributes(self, visitor: &mut impl Visitor<'hir>) { let krate = self.krate(); for info in krate.owners.iter() { if let MaybeOwner::Owner(info) = info { for attrs in info.attrs.map.values() { for a in *attrs { visitor.visit_attribute(a) } } } } } /// Visits all item-likes in the crate in some deterministic (but unspecified) order. If you /// need to process every item-like, and don't care about visiting nested items in a particular /// order then this method is the best choice. If you do care about this nesting, you should /// use the `tcx.hir().walk_toplevel_module`. /// /// Note that this function will access HIR for all the item-likes in the crate. If you only /// need to access some of them, it is usually better to manually loop on the iterators /// provided by `tcx.hir_crate_items(())`. /// /// Please see the notes in `intravisit.rs` for more information. pub fn visit_all_item_likes_in_crate(self, visitor: &mut V) where V: Visitor<'hir>, { let krate = self.tcx.hir_crate_items(()); for id in krate.items() { visitor.visit_item(self.item(id)); } for id in krate.trait_items() { visitor.visit_trait_item(self.trait_item(id)); } for id in krate.impl_items() { visitor.visit_impl_item(self.impl_item(id)); } for id in krate.foreign_items() { visitor.visit_foreign_item(self.foreign_item(id)); } } /// This method is the equivalent of `visit_all_item_likes_in_crate` but restricted to /// item-likes in a single module. pub fn visit_item_likes_in_module(self, module: LocalDefId, visitor: &mut V) where V: Visitor<'hir>, { let module = self.tcx.hir_module_items(module); for id in module.items() { visitor.visit_item(self.item(id)); } for id in module.trait_items() { visitor.visit_trait_item(self.trait_item(id)); } for id in module.impl_items() { visitor.visit_impl_item(self.impl_item(id)); } for id in module.foreign_items() { visitor.visit_foreign_item(self.foreign_item(id)); } } pub fn for_each_module(self, mut f: impl FnMut(LocalDefId)) { let crate_items = self.tcx.hir_crate_items(()); for module in crate_items.submodules.iter() { f(module.def_id) } } #[inline] pub fn par_for_each_module(self, f: impl Fn(LocalDefId) + Sync + Send) { let crate_items = self.tcx.hir_crate_items(()); par_for_each_in(&crate_items.submodules[..], |module| f(module.def_id)) } /// Returns an iterator for the nodes in the ancestor tree of the `current_id` /// until the crate root is reached. Prefer this over your own loop using `get_parent_node`. #[inline] pub fn parent_id_iter(self, current_id: HirId) -> impl Iterator + 'hir { ParentHirIterator { current_id, map: self } } /// Returns an iterator for the nodes in the ancestor tree of the `current_id` /// until the crate root is reached. Prefer this over your own loop using `get_parent_node`. #[inline] pub fn parent_iter(self, current_id: HirId) -> impl Iterator)> { self.parent_id_iter(current_id).filter_map(move |id| Some((id, self.find(id)?))) } /// Returns an iterator for the nodes in the ancestor tree of the `current_id` /// until the crate root is reached. Prefer this over your own loop using `get_parent_node`. #[inline] pub fn parent_owner_iter(self, current_id: HirId) -> ParentOwnerIterator<'hir> { ParentOwnerIterator { current_id, map: self } } /// Checks if the node is left-hand side of an assignment. pub fn is_lhs(self, id: HirId) -> bool { match self.find(self.get_parent_node(id)) { Some(Node::Expr(expr)) => match expr.kind { ExprKind::Assign(lhs, _rhs, _span) => lhs.hir_id == id, _ => false, }, _ => false, } } /// Whether the expression pointed at by `hir_id` belongs to a `const` evaluation context. /// Used exclusively for diagnostics, to avoid suggestion function calls. pub fn is_inside_const_context(self, hir_id: HirId) -> bool { self.body_const_context(self.enclosing_body_owner(hir_id)).is_some() } /// Retrieves the `HirId` for `id`'s enclosing method, unless there's a /// `while` or `loop` before reaching it, as block tail returns are not /// available in them. /// /// ``` /// fn foo(x: usize) -> bool { /// if x == 1 { /// true // If `get_return_block` gets passed the `id` corresponding /// } else { // to this, it will return `foo`'s `HirId`. /// false /// } /// } /// ``` /// /// ```compile_fail,E0308 /// fn foo(x: usize) -> bool { /// loop { /// true // If `get_return_block` gets passed the `id` corresponding /// } // to this, it will return `None`. /// false /// } /// ``` pub fn get_return_block(self, id: HirId) -> Option { let mut iter = self.parent_iter(id).peekable(); let mut ignore_tail = false; if let Some(node) = self.find(id) { if let Node::Expr(Expr { kind: ExprKind::Ret(_), .. }) = node { // When dealing with `return` statements, we don't care about climbing only tail // expressions. ignore_tail = true; } } while let Some((hir_id, node)) = iter.next() { if let (Some((_, next_node)), false) = (iter.peek(), ignore_tail) { match next_node { Node::Block(Block { expr: None, .. }) => return None, // The current node is not the tail expression of its parent. Node::Block(Block { expr: Some(e), .. }) if hir_id != e.hir_id => return None, _ => {} } } match node { Node::Item(_) | Node::ForeignItem(_) | Node::TraitItem(_) | Node::Expr(Expr { kind: ExprKind::Closure { .. }, .. }) | Node::ImplItem(_) => return Some(hir_id), // Ignore `return`s on the first iteration Node::Expr(Expr { kind: ExprKind::Loop(..) | ExprKind::Ret(..), .. }) | Node::Local(_) => { return None; } _ => {} } } None } /// Retrieves the `OwnerId` for `id`'s parent item, or `id` itself if no /// parent item is in this map. The "parent item" is the closest parent node /// in the HIR which is recorded by the map and is an item, either an item /// in a module, trait, or impl. pub fn get_parent_item(self, hir_id: HirId) -> OwnerId { if let Some((def_id, _node)) = self.parent_owner_iter(hir_id).next() { def_id } else { CRATE_OWNER_ID } } /// Returns the `OwnerId` of `id`'s nearest module parent, or `id` itself if no /// module parent is in this map. pub(super) fn get_module_parent_node(self, hir_id: HirId) -> OwnerId { for (def_id, node) in self.parent_owner_iter(hir_id) { if let OwnerNode::Item(&Item { kind: ItemKind::Mod(_), .. }) = node { return def_id; } } CRATE_OWNER_ID } /// When on an if expression, a match arm tail expression or a match arm, give back /// the enclosing `if` or `match` expression. /// /// Used by error reporting when there's a type error in an if or match arm caused by the /// expression needing to be unit. pub fn get_if_cause(self, hir_id: HirId) -> Option<&'hir Expr<'hir>> { for (_, node) in self.parent_iter(hir_id) { match node { Node::Item(_) | Node::ForeignItem(_) | Node::TraitItem(_) | Node::ImplItem(_) | Node::Stmt(Stmt { kind: StmtKind::Local(_), .. }) => break, Node::Expr(expr @ Expr { kind: ExprKind::If(..) | ExprKind::Match(..), .. }) => { return Some(expr); } _ => {} } } None } /// Returns the nearest enclosing scope. A scope is roughly an item or block. pub fn get_enclosing_scope(self, hir_id: HirId) -> Option { for (hir_id, node) in self.parent_iter(hir_id) { if let Node::Item(Item { kind: ItemKind::Fn(..) | ItemKind::Const(..) | ItemKind::Static(..) | ItemKind::Mod(..) | ItemKind::Enum(..) | ItemKind::Struct(..) | ItemKind::Union(..) | ItemKind::Trait(..) | ItemKind::Impl { .. }, .. }) | Node::ForeignItem(ForeignItem { kind: ForeignItemKind::Fn(..), .. }) | Node::TraitItem(TraitItem { kind: TraitItemKind::Fn(..), .. }) | Node::ImplItem(ImplItem { kind: ImplItemKind::Fn(..), .. }) | Node::Block(_) = node { return Some(hir_id); } } None } /// Returns the defining scope for an opaque type definition. pub fn get_defining_scope(self, id: HirId) -> HirId { let mut scope = id; loop { scope = self.get_enclosing_scope(scope).unwrap_or(CRATE_HIR_ID); if scope == CRATE_HIR_ID || !matches!(self.get(scope), Node::Block(_)) { return scope; } } } pub fn get_foreign_abi(self, hir_id: HirId) -> Abi { let parent = self.get_parent_item(hir_id); if let Some(node) = self.tcx.hir_owner(parent) { if let OwnerNode::Item(Item { kind: ItemKind::ForeignMod { abi, .. }, .. }) = node.node { return *abi; } } bug!( "expected foreign mod or inlined parent, found {}", self.node_to_string(HirId::make_owner(parent.def_id)) ) } pub fn expect_owner(self, id: OwnerId) -> OwnerNode<'hir> { self.tcx.hir_owner(id).unwrap_or_else(|| bug!("expected owner for {:?}", id)).node } pub fn expect_item(self, id: LocalDefId) -> &'hir Item<'hir> { match self.tcx.hir_owner(OwnerId { def_id: id }) { Some(Owner { node: OwnerNode::Item(item), .. }) => item, _ => bug!("expected item, found {}", self.node_to_string(HirId::make_owner(id))), } } pub fn expect_impl_item(self, id: LocalDefId) -> &'hir ImplItem<'hir> { match self.tcx.hir_owner(OwnerId { def_id: id }) { Some(Owner { node: OwnerNode::ImplItem(item), .. }) => item, _ => bug!("expected impl item, found {}", self.node_to_string(HirId::make_owner(id))), } } pub fn expect_trait_item(self, id: LocalDefId) -> &'hir TraitItem<'hir> { match self.tcx.hir_owner(OwnerId { def_id: id }) { Some(Owner { node: OwnerNode::TraitItem(item), .. }) => item, _ => bug!("expected trait item, found {}", self.node_to_string(HirId::make_owner(id))), } } pub fn expect_variant(self, id: HirId) -> &'hir Variant<'hir> { match self.find(id) { Some(Node::Variant(variant)) => variant, _ => bug!("expected variant, found {}", self.node_to_string(id)), } } pub fn expect_foreign_item(self, id: OwnerId) -> &'hir ForeignItem<'hir> { match self.tcx.hir_owner(id) { Some(Owner { node: OwnerNode::ForeignItem(item), .. }) => item, _ => { bug!( "expected foreign item, found {}", self.node_to_string(HirId::make_owner(id.def_id)) ) } } } pub fn expect_expr(self, id: HirId) -> &'hir Expr<'hir> { match self.find(id) { Some(Node::Expr(expr)) => expr, _ => bug!("expected expr, found {}", self.node_to_string(id)), } } #[inline] fn opt_ident(self, id: HirId) -> Option { match self.get(id) { Node::Pat(&Pat { kind: PatKind::Binding(_, _, ident, _), .. }) => Some(ident), // A `Ctor` doesn't have an identifier itself, but its parent // struct/variant does. Compare with `hir::Map::opt_span`. Node::Ctor(..) => match self.find(self.get_parent_node(id))? { Node::Item(item) => Some(item.ident), Node::Variant(variant) => Some(variant.ident), _ => unreachable!(), }, node => node.ident(), } } #[inline] pub(super) fn opt_ident_span(self, id: HirId) -> Option { self.opt_ident(id).map(|ident| ident.span) } #[inline] pub fn opt_name(self, id: HirId) -> Option { self.opt_ident(id).map(|ident| ident.name) } pub fn name(self, id: HirId) -> Symbol { self.opt_name(id).unwrap_or_else(|| bug!("no name for {}", self.node_to_string(id))) } /// Given a node ID, gets a list of attributes associated with the AST /// corresponding to the node-ID. pub fn attrs(self, id: HirId) -> &'hir [ast::Attribute] { self.tcx.hir_attrs(id.owner).get(id.local_id) } /// Gets the span of the definition of the specified HIR node. /// This is used by `tcx.def_span`. pub fn span(self, hir_id: HirId) -> Span { self.opt_span(hir_id) .unwrap_or_else(|| bug!("hir::map::Map::span: id not in map: {:?}", hir_id)) } pub fn opt_span(self, hir_id: HirId) -> Option { fn until_within(outer: Span, end: Span) -> Span { if let Some(end) = end.find_ancestor_inside(outer) { outer.with_hi(end.hi()) } else { outer } } fn named_span(item_span: Span, ident: Ident, generics: Option<&Generics<'_>>) -> Span { if ident.name != kw::Empty { let mut span = until_within(item_span, ident.span); if let Some(g) = generics && !g.span.is_dummy() && let Some(g_span) = g.span.find_ancestor_inside(item_span) { span = span.to(g_span); } span } else { item_span } } let span = match self.find(hir_id)? { // Function-like. Node::Item(Item { kind: ItemKind::Fn(sig, ..), span: outer_span, .. }) | Node::TraitItem(TraitItem { kind: TraitItemKind::Fn(sig, ..), span: outer_span, .. }) | Node::ImplItem(ImplItem { kind: ImplItemKind::Fn(sig, ..), span: outer_span, .. }) => { // Ensure that the returned span has the item's SyntaxContext, and not the // SyntaxContext of the visibility. sig.span.find_ancestor_in_same_ctxt(*outer_span).unwrap_or(*outer_span) } // Constants and Statics. Node::Item(Item { kind: ItemKind::Const(ty, ..) | ItemKind::Static(ty, ..) | ItemKind::Impl(Impl { self_ty: ty, .. }), span: outer_span, .. }) | Node::TraitItem(TraitItem { kind: TraitItemKind::Const(ty, ..), span: outer_span, .. }) | Node::ImplItem(ImplItem { kind: ImplItemKind::Const(ty, ..), span: outer_span, .. }) | Node::ForeignItem(ForeignItem { kind: ForeignItemKind::Static(ty, ..), span: outer_span, .. }) => until_within(*outer_span, ty.span), // With generics and bounds. Node::Item(Item { kind: ItemKind::Trait(_, _, generics, bounds, _), span: outer_span, .. }) | Node::TraitItem(TraitItem { kind: TraitItemKind::Type(bounds, _), generics, span: outer_span, .. }) => { let end = if let Some(b) = bounds.last() { b.span() } else { generics.span }; until_within(*outer_span, end) } // Other cases. Node::Item(item) => match &item.kind { ItemKind::Use(path, _) => { // Ensure that the returned span has the item's SyntaxContext, and not the // SyntaxContext of the path. path.span.find_ancestor_in_same_ctxt(item.span).unwrap_or(item.span) } _ => named_span(item.span, item.ident, item.kind.generics()), }, Node::Variant(variant) => named_span(variant.span, variant.ident, None), Node::ImplItem(item) => named_span(item.span, item.ident, Some(item.generics)), Node::ForeignItem(item) => match item.kind { ForeignItemKind::Fn(decl, _, _) => until_within(item.span, decl.output.span()), _ => named_span(item.span, item.ident, None), }, Node::Ctor(_) => return self.opt_span(self.get_parent_node(hir_id)), Node::Expr(Expr { kind: ExprKind::Closure(Closure { fn_decl_span, .. }), span, .. }) => { // Ensure that the returned span has the item's SyntaxContext. fn_decl_span.find_ancestor_in_same_ctxt(*span).unwrap_or(*span) } _ => self.span_with_body(hir_id), }; debug_assert_eq!(span.ctxt(), self.span_with_body(hir_id).ctxt()); Some(span) } /// Like `hir.span()`, but includes the body of items /// (instead of just the item header) pub fn span_with_body(self, hir_id: HirId) -> Span { match self.get(hir_id) { Node::Param(param) => param.span, Node::Item(item) => item.span, Node::ForeignItem(foreign_item) => foreign_item.span, Node::TraitItem(trait_item) => trait_item.span, Node::ImplItem(impl_item) => impl_item.span, Node::Variant(variant) => variant.span, Node::Field(field) => field.span, Node::AnonConst(constant) => self.body(constant.body).value.span, Node::Expr(expr) => expr.span, Node::ExprField(field) => field.span, Node::Stmt(stmt) => stmt.span, Node::PathSegment(seg) => { let ident_span = seg.ident.span; ident_span .with_hi(seg.args.map_or_else(|| ident_span.hi(), |args| args.span_ext.hi())) } Node::Ty(ty) => ty.span, Node::TypeBinding(tb) => tb.span, Node::TraitRef(tr) => tr.path.span, Node::Pat(pat) => pat.span, Node::PatField(field) => field.span, Node::Arm(arm) => arm.span, Node::Block(block) => block.span, Node::Ctor(..) => self.span_with_body(self.get_parent_node(hir_id)), Node::Lifetime(lifetime) => lifetime.span, Node::GenericParam(param) => param.span, Node::Infer(i) => i.span, Node::Local(local) => local.span, Node::Crate(item) => item.spans.inner_span, } } pub fn span_if_local(self, id: DefId) -> Option { if id.is_local() { Some(self.tcx.def_span(id)) } else { None } } pub fn res_span(self, res: Res) -> Option { match res { Res::Err => None, Res::Local(id) => Some(self.span(id)), res => self.span_if_local(res.opt_def_id()?), } } /// Get a representation of this `id` for debugging purposes. /// NOTE: Do NOT use this in diagnostics! pub fn node_to_string(self, id: HirId) -> String { hir_id_to_string(self, id) } /// Returns the HirId of `N` in `struct Foo` when /// called with the HirId for the `{ ... }` anon const pub fn opt_const_param_default_param_hir_id(self, anon_const: HirId) -> Option { match self.get(self.get_parent_node(anon_const)) { Node::GenericParam(GenericParam { hir_id: param_id, kind: GenericParamKind::Const { .. }, .. }) => Some(*param_id), _ => None, } } } impl<'hir> intravisit::Map<'hir> for Map<'hir> { fn find(&self, hir_id: HirId) -> Option> { (*self).find(hir_id) } fn body(&self, id: BodyId) -> &'hir Body<'hir> { (*self).body(id) } fn item(&self, id: ItemId) -> &'hir Item<'hir> { (*self).item(id) } fn trait_item(&self, id: TraitItemId) -> &'hir TraitItem<'hir> { (*self).trait_item(id) } fn impl_item(&self, id: ImplItemId) -> &'hir ImplItem<'hir> { (*self).impl_item(id) } fn foreign_item(&self, id: ForeignItemId) -> &'hir ForeignItem<'hir> { (*self).foreign_item(id) } } pub(super) fn crate_hash(tcx: TyCtxt<'_>, crate_num: CrateNum) -> Svh { debug_assert_eq!(crate_num, LOCAL_CRATE); let krate = tcx.hir_crate(()); let hir_body_hash = krate.hir_hash; let upstream_crates = upstream_crates(tcx); let resolutions = tcx.resolutions(()); // We hash the final, remapped names of all local source files so we // don't have to include the path prefix remapping commandline args. // If we included the full mapping in the SVH, we could only have // reproducible builds by compiling from the same directory. So we just // hash the result of the mapping instead of the mapping itself. let mut source_file_names: Vec<_> = tcx .sess .source_map() .files() .iter() .filter(|source_file| source_file.cnum == LOCAL_CRATE) .map(|source_file| source_file.name_hash) .collect(); source_file_names.sort_unstable(); let crate_hash: Fingerprint = tcx.with_stable_hashing_context(|mut hcx| { let mut stable_hasher = StableHasher::new(); hir_body_hash.hash_stable(&mut hcx, &mut stable_hasher); upstream_crates.hash_stable(&mut hcx, &mut stable_hasher); source_file_names.hash_stable(&mut hcx, &mut stable_hasher); if tcx.sess.opts.unstable_opts.incremental_relative_spans { let definitions = tcx.definitions_untracked(); let mut owner_spans: Vec<_> = krate .owners .iter_enumerated() .filter_map(|(def_id, info)| { let _ = info.as_owner()?; let def_path_hash = definitions.def_path_hash(def_id); let span = resolutions.source_span.get(def_id).unwrap_or(&DUMMY_SP); debug_assert_eq!(span.parent(), None); Some((def_path_hash, span)) }) .collect(); owner_spans.sort_unstable_by_key(|bn| bn.0); owner_spans.hash_stable(&mut hcx, &mut stable_hasher); } tcx.sess.opts.dep_tracking_hash(true).hash_stable(&mut hcx, &mut stable_hasher); tcx.sess.local_stable_crate_id().hash_stable(&mut hcx, &mut stable_hasher); // Hash visibility information since it does not appear in HIR. resolutions.visibilities.hash_stable(&mut hcx, &mut stable_hasher); resolutions.has_pub_restricted.hash_stable(&mut hcx, &mut stable_hasher); stable_hasher.finish() }); Svh::new(crate_hash.to_smaller_hash()) } fn upstream_crates(tcx: TyCtxt<'_>) -> Vec<(StableCrateId, Svh)> { let mut upstream_crates: Vec<_> = tcx .crates(()) .iter() .map(|&cnum| { let stable_crate_id = tcx.stable_crate_id(cnum); let hash = tcx.crate_hash(cnum); (stable_crate_id, hash) }) .collect(); upstream_crates.sort_unstable_by_key(|&(stable_crate_id, _)| stable_crate_id); upstream_crates } fn hir_id_to_string(map: Map<'_>, id: HirId) -> String { let id_str = format!(" (hir_id={})", id); let path_str = || { // This functionality is used for debugging, try to use `TyCtxt` to get // the user-friendly path, otherwise fall back to stringifying `DefPath`. crate::ty::tls::with_opt(|tcx| { if let Some(tcx) = tcx { let def_id = map.local_def_id(id); tcx.def_path_str(def_id.to_def_id()) } else if let Some(path) = map.def_path_from_hir_id(id) { path.data.into_iter().map(|elem| elem.to_string()).collect::>().join("::") } else { String::from("") } }) }; let span_str = || map.tcx.sess.source_map().span_to_snippet(map.span(id)).unwrap_or_default(); let node_str = |prefix| format!("{} {}{}", prefix, span_str(), id_str); match map.find(id) { Some(Node::Item(item)) => { let item_str = match item.kind { ItemKind::ExternCrate(..) => "extern crate", ItemKind::Use(..) => "use", ItemKind::Static(..) => "static", ItemKind::Const(..) => "const", ItemKind::Fn(..) => "fn", ItemKind::Macro(..) => "macro", ItemKind::Mod(..) => "mod", ItemKind::ForeignMod { .. } => "foreign mod", ItemKind::GlobalAsm(..) => "global asm", ItemKind::TyAlias(..) => "ty", ItemKind::OpaqueTy(ref opaque) => { if opaque.in_trait { "opaque type in trait" } else { "opaque type" } } ItemKind::Enum(..) => "enum", ItemKind::Struct(..) => "struct", ItemKind::Union(..) => "union", ItemKind::Trait(..) => "trait", ItemKind::TraitAlias(..) => "trait alias", ItemKind::Impl { .. } => "impl", }; format!("{} {}{}", item_str, path_str(), id_str) } Some(Node::ForeignItem(_)) => format!("foreign item {}{}", path_str(), id_str), Some(Node::ImplItem(ii)) => match ii.kind { ImplItemKind::Const(..) => { format!("assoc const {} in {}{}", ii.ident, path_str(), id_str) } ImplItemKind::Fn(..) => format!("method {} in {}{}", ii.ident, path_str(), id_str), ImplItemKind::Type(_) => { format!("assoc type {} in {}{}", ii.ident, path_str(), id_str) } }, Some(Node::TraitItem(ti)) => { let kind = match ti.kind { TraitItemKind::Const(..) => "assoc constant", TraitItemKind::Fn(..) => "trait method", TraitItemKind::Type(..) => "assoc type", }; format!("{} {} in {}{}", kind, ti.ident, path_str(), id_str) } Some(Node::Variant(ref variant)) => { format!("variant {} in {}{}", variant.ident, path_str(), id_str) } Some(Node::Field(ref field)) => { format!("field {} in {}{}", field.ident, path_str(), id_str) } Some(Node::AnonConst(_)) => node_str("const"), Some(Node::Expr(_)) => node_str("expr"), Some(Node::ExprField(_)) => node_str("expr field"), Some(Node::Stmt(_)) => node_str("stmt"), Some(Node::PathSegment(_)) => node_str("path segment"), Some(Node::Ty(_)) => node_str("type"), Some(Node::TypeBinding(_)) => node_str("type binding"), Some(Node::TraitRef(_)) => node_str("trait ref"), Some(Node::Pat(_)) => node_str("pat"), Some(Node::PatField(_)) => node_str("pattern field"), Some(Node::Param(_)) => node_str("param"), Some(Node::Arm(_)) => node_str("arm"), Some(Node::Block(_)) => node_str("block"), Some(Node::Infer(_)) => node_str("infer"), Some(Node::Local(_)) => node_str("local"), Some(Node::Ctor(..)) => format!("ctor {}{}", path_str(), id_str), Some(Node::Lifetime(_)) => node_str("lifetime"), Some(Node::GenericParam(ref param)) => format!("generic_param {:?}{}", param, id_str), Some(Node::Crate(..)) => String::from("root_crate"), None => format!("unknown node{}", id_str), } } pub(super) fn hir_module_items(tcx: TyCtxt<'_>, module_id: LocalDefId) -> ModuleItems { let mut collector = ItemCollector::new(tcx, false); let (hir_mod, span, hir_id) = tcx.hir().get_module(module_id); collector.visit_mod(hir_mod, span, hir_id); let ItemCollector { submodules, items, trait_items, impl_items, foreign_items, body_owners, .. } = collector; return ModuleItems { submodules: submodules.into_boxed_slice(), items: items.into_boxed_slice(), trait_items: trait_items.into_boxed_slice(), impl_items: impl_items.into_boxed_slice(), foreign_items: foreign_items.into_boxed_slice(), body_owners: body_owners.into_boxed_slice(), }; } pub(crate) fn hir_crate_items(tcx: TyCtxt<'_>, _: ()) -> ModuleItems { let mut collector = ItemCollector::new(tcx, true); // A "crate collector" and "module collector" start at a // module item (the former starts at the crate root) but only // the former needs to collect it. ItemCollector does not do this for us. collector.submodules.push(CRATE_OWNER_ID); tcx.hir().walk_toplevel_module(&mut collector); let ItemCollector { submodules, items, trait_items, impl_items, foreign_items, body_owners, .. } = collector; return ModuleItems { submodules: submodules.into_boxed_slice(), items: items.into_boxed_slice(), trait_items: trait_items.into_boxed_slice(), impl_items: impl_items.into_boxed_slice(), foreign_items: foreign_items.into_boxed_slice(), body_owners: body_owners.into_boxed_slice(), }; } struct ItemCollector<'tcx> { // When true, it collects all items in the create, // otherwise it collects items in some module. crate_collector: bool, tcx: TyCtxt<'tcx>, submodules: Vec, items: Vec, trait_items: Vec, impl_items: Vec, foreign_items: Vec, body_owners: Vec, } impl<'tcx> ItemCollector<'tcx> { fn new(tcx: TyCtxt<'tcx>, crate_collector: bool) -> ItemCollector<'tcx> { ItemCollector { crate_collector, tcx, submodules: Vec::default(), items: Vec::default(), trait_items: Vec::default(), impl_items: Vec::default(), foreign_items: Vec::default(), body_owners: Vec::default(), } } } impl<'hir> Visitor<'hir> for ItemCollector<'hir> { type NestedFilter = nested_filter::All; fn nested_visit_map(&mut self) -> Self::Map { self.tcx.hir() } fn visit_item(&mut self, item: &'hir Item<'hir>) { if associated_body(Node::Item(item)).is_some() { self.body_owners.push(item.owner_id.def_id); } self.items.push(item.item_id()); // Items that are modules are handled here instead of in visit_mod. if let ItemKind::Mod(module) = &item.kind { self.submodules.push(item.owner_id); // A module collector does not recurse inside nested modules. if self.crate_collector { intravisit::walk_mod(self, module, item.hir_id()); } } else { intravisit::walk_item(self, item) } } fn visit_foreign_item(&mut self, item: &'hir ForeignItem<'hir>) { self.foreign_items.push(item.foreign_item_id()); intravisit::walk_foreign_item(self, item) } fn visit_anon_const(&mut self, c: &'hir AnonConst) { self.body_owners.push(self.tcx.hir().local_def_id(c.hir_id)); intravisit::walk_anon_const(self, c) } fn visit_expr(&mut self, ex: &'hir Expr<'hir>) { if matches!(ex.kind, ExprKind::Closure { .. }) { self.body_owners.push(self.tcx.hir().local_def_id(ex.hir_id)); } intravisit::walk_expr(self, ex) } fn visit_trait_item(&mut self, item: &'hir TraitItem<'hir>) { if associated_body(Node::TraitItem(item)).is_some() { self.body_owners.push(item.owner_id.def_id); } self.trait_items.push(item.trait_item_id()); intravisit::walk_trait_item(self, item) } fn visit_impl_item(&mut self, item: &'hir ImplItem<'hir>) { if associated_body(Node::ImplItem(item)).is_some() { self.body_owners.push(item.owner_id.def_id); } self.impl_items.push(item.impl_item_id()); intravisit::walk_impl_item(self, item) } }