diff options
Diffstat (limited to '')
| -rw-r--r-- | compiler/rustc_ast_lowering/src/lib.rs | 158 |
1 files changed, 82 insertions, 76 deletions
diff --git a/compiler/rustc_ast_lowering/src/lib.rs b/compiler/rustc_ast_lowering/src/lib.rs index 9012aa704..ff29d15f1 100644 --- a/compiler/rustc_ast_lowering/src/lib.rs +++ b/compiler/rustc_ast_lowering/src/lib.rs @@ -32,7 +32,6 @@ #![feature(box_patterns)] #![feature(let_chains)] -#![cfg_attr(bootstrap, feature(let_else))] #![feature(never_type)] #![recursion_limit = "256"] #![allow(rustc::potential_query_instability)] @@ -62,8 +61,8 @@ use rustc_hir::def_id::{LocalDefId, CRATE_DEF_ID}; use rustc_hir::definitions::DefPathData; use rustc_hir::{ConstArg, GenericArg, ItemLocalId, ParamName, TraitCandidate}; use rustc_index::vec::{Idx, IndexVec}; -use rustc_middle::span_bug; use rustc_middle::ty::{ResolverAstLowering, TyCtxt}; +use rustc_middle::{bug, span_bug}; use rustc_session::parse::feature_err; use rustc_span::hygiene::MacroKind; use rustc_span::source_map::DesugaringKind; @@ -126,7 +125,7 @@ struct LoweringContext<'a, 'hir> { is_in_trait_impl: bool, is_in_dyn_type: bool, - current_hir_id_owner: LocalDefId, + current_hir_id_owner: hir::OwnerId, item_local_id_counter: hir::ItemLocalId, local_id_to_def_id: SortedMap<ItemLocalId, LocalDefId>, trait_map: FxHashMap<ItemLocalId, Box<[TraitCandidate]>>, @@ -161,6 +160,10 @@ trait ResolverAstLoweringExt { fn legacy_const_generic_args(&self, expr: &Expr) -> Option<Vec<usize>>; fn get_partial_res(&self, id: NodeId) -> Option<PartialRes>; fn get_import_res(&self, id: NodeId) -> PerNS<Option<Res<NodeId>>>; + // Clones the resolution (if any) on 'source' and applies it + // to 'target'. Used when desugaring a `UseTreeKind::Nested` to + // multiple `UseTreeKind::Simple`s + fn clone_res(&mut self, source: NodeId, target: NodeId); fn get_label_res(&self, id: NodeId) -> Option<NodeId>; fn get_lifetime_res(&self, id: NodeId) -> Option<LifetimeRes>; fn take_extra_lifetime_params(&mut self, id: NodeId) -> Vec<(Ident, NodeId, LifetimeRes)>; @@ -176,12 +179,7 @@ impl ResolverAstLoweringExt for ResolverAstLowering { return None; } - let partial_res = self.partial_res_map.get(&expr.id)?; - if partial_res.unresolved_segments() != 0 { - return None; - } - - if let Res::Def(DefKind::Fn, def_id) = partial_res.base_res() { + if let Res::Def(DefKind::Fn, def_id) = self.partial_res_map.get(&expr.id)?.full_res()? { // We only support cross-crate argument rewriting. Uses // within the same crate should be updated to use the new // const generics style. @@ -198,6 +196,12 @@ impl ResolverAstLoweringExt for ResolverAstLowering { None } + fn clone_res(&mut self, source: NodeId, target: NodeId) { + if let Some(res) = self.partial_res_map.get(&source) { + self.partial_res_map.insert(target, *res); + } + } + /// Obtains resolution for a `NodeId` with a single resolution. fn get_partial_res(&self, id: NodeId) -> Option<PartialRes> { self.partial_res_map.get(&id).copied() @@ -324,17 +328,20 @@ enum FnDeclKind { } impl FnDeclKind { - fn impl_trait_return_allowed(&self, tcx: TyCtxt<'_>) -> bool { + fn impl_trait_allowed(&self, tcx: TyCtxt<'_>) -> bool { match self { FnDeclKind::Fn | FnDeclKind::Inherent => true, FnDeclKind::Impl if tcx.features().return_position_impl_trait_in_trait => true, + FnDeclKind::Trait if tcx.features().return_position_impl_trait_in_trait => true, _ => false, } } - fn impl_trait_in_trait_allowed(&self, tcx: TyCtxt<'_>) -> bool { + fn async_fn_allowed(&self, tcx: TyCtxt<'_>) -> bool { match self { - FnDeclKind::Trait if tcx.features().return_position_impl_trait_in_trait => true, + FnDeclKind::Fn | FnDeclKind::Inherent => true, + FnDeclKind::Impl if tcx.features().async_fn_in_trait => true, + FnDeclKind::Trait if tcx.features().async_fn_in_trait => true, _ => false, } } @@ -572,7 +579,8 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { let current_node_ids = std::mem::take(&mut self.node_id_to_local_id); let current_id_to_def_id = std::mem::take(&mut self.local_id_to_def_id); let current_trait_map = std::mem::take(&mut self.trait_map); - let current_owner = std::mem::replace(&mut self.current_hir_id_owner, def_id); + let current_owner = + std::mem::replace(&mut self.current_hir_id_owner, hir::OwnerId { def_id }); let current_local_counter = std::mem::replace(&mut self.item_local_id_counter, hir::ItemLocalId::new(1)); let current_impl_trait_defs = std::mem::take(&mut self.impl_trait_defs); @@ -587,7 +595,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { debug_assert_eq!(_old, None); let item = f(self); - debug_assert_eq!(def_id, item.def_id()); + debug_assert_eq!(def_id, item.def_id().def_id); // `f` should have consumed all the elements in these vectors when constructing `item`. debug_assert!(self.impl_trait_defs.is_empty()); debug_assert!(self.impl_trait_bounds.is_empty()); @@ -753,12 +761,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { } fn expect_full_res(&mut self, id: NodeId) -> Res<NodeId> { - self.resolver.get_partial_res(id).map_or(Res::Err, |pr| { - if pr.unresolved_segments() != 0 { - panic!("path not fully resolved: {:?}", pr); - } - pr.base_res() - }) + self.resolver.get_partial_res(id).map_or(Res::Err, |pr| pr.expect_full_res()) } fn expect_full_res_from_use(&mut self, id: NodeId) -> impl Iterator<Item = Res<NodeId>> { @@ -786,7 +789,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { /// Mark a span as relative to the current owning item. fn lower_span(&self, span: Span) -> Span { if self.tcx.sess.opts.unstable_opts.incremental_relative_spans { - span.with_parent(Some(self.current_hir_id_owner)) + span.with_parent(Some(self.current_hir_id_owner.def_id)) } else { // Do not make spans relative when not using incremental compilation. span @@ -812,7 +815,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { LifetimeRes::Fresh { param, .. } => { // Late resolution delegates to us the creation of the `LocalDefId`. let _def_id = self.create_def( - self.current_hir_id_owner, + self.current_hir_id_owner.def_id, param, DefPathData::LifetimeNs(kw::UnderscoreLifetime), ); @@ -1060,9 +1063,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { // Desugar `AssocTy: Bounds` into `AssocTy = impl Bounds`. We do this by // constructing the HIR for `impl bounds...` and then lowering that. - let parent_def_id = self.current_hir_id_owner; let impl_trait_node_id = self.next_node_id(); - self.create_def(parent_def_id, impl_trait_node_id, DefPathData::ImplTrait); self.with_dyn_type_scope(false, |this| { let node_id = this.next_node_id(); @@ -1140,8 +1141,11 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { // type and value namespaces. If we resolved the path in the value namespace, we // transform it into a generic const argument. TyKind::Path(ref qself, ref path) => { - if let Some(partial_res) = self.resolver.get_partial_res(ty.id) { - let res = partial_res.base_res(); + if let Some(res) = self + .resolver + .get_partial_res(ty.id) + .and_then(|partial_res| partial_res.full_res()) + { if !res.matches_ns(Namespace::TypeNS) { debug!( "lower_generic_arg: Lowering type argument as const argument: {:?}", @@ -1154,7 +1158,11 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { let node_id = self.next_node_id(); // Add a definition for the in-band const def. - self.create_def(parent_def_id, node_id, DefPathData::AnonConst); + self.create_def( + parent_def_id.def_id, + node_id, + DefPathData::AnonConst, + ); let span = self.lower_span(ty.span); let path_expr = Expr { @@ -1204,8 +1212,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { // by `ty_path`. if qself.is_none() && let Some(partial_res) = self.resolver.get_partial_res(t.id) - && partial_res.unresolved_segments() == 0 - && let Res::Def(DefKind::Trait | DefKind::TraitAlias, _) = partial_res.base_res() + && let Some(Res::Def(DefKind::Trait | DefKind::TraitAlias, _)) = partial_res.full_res() { let (bounds, lifetime_bound) = self.with_dyn_type_scope(true, |this| { let poly_trait_ref = this.ast_arena.ptr.alloc(PolyTraitRef { @@ -1349,9 +1356,14 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { def_node_id, bounds, false, - &ImplTraitContext::TypeAliasesOpaqueTy, + itctx, ), ImplTraitContext::Universal => { + self.create_def( + self.current_hir_id_owner.def_id, + def_node_id, + DefPathData::ImplTrait, + ); let span = t.span; let ident = Ident::from_str_and_span(&pprust::ty_to_string(t), span); let (param, bounds, path) = @@ -1445,7 +1457,17 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { // frequently opened issues show. let opaque_ty_span = self.mark_span_with_reason(DesugaringKind::OpaqueTy, span, None); - let opaque_ty_def_id = self.local_def_id(opaque_ty_node_id); + let opaque_ty_def_id = match origin { + hir::OpaqueTyOrigin::TyAlias => self.create_def( + self.current_hir_id_owner.def_id, + opaque_ty_node_id, + DefPathData::ImplTrait, + ), + hir::OpaqueTyOrigin::FnReturn(fn_def_id) => { + self.create_def(fn_def_id, opaque_ty_node_id, DefPathData::ImplTrait) + } + hir::OpaqueTyOrigin::AsyncFn(..) => bug!("unreachable"), + }; debug!(?opaque_ty_def_id); // Contains the new lifetime definitions created for the TAIT (if any). @@ -1551,7 +1573,11 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { debug!(?lifetimes); // `impl Trait` now just becomes `Foo<'a, 'b, ..>`. - hir::TyKind::OpaqueDef(hir::ItemId { def_id: opaque_ty_def_id }, lifetimes, in_trait) + hir::TyKind::OpaqueDef( + hir::ItemId { owner_id: hir::OwnerId { def_id: opaque_ty_def_id } }, + lifetimes, + in_trait, + ) } /// Registers a new opaque type with the proper `NodeId`s and @@ -1567,7 +1593,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { // Generate an `type Foo = impl Trait;` declaration. trace!("registering opaque type with id {:#?}", opaque_ty_id); let opaque_ty_item = hir::Item { - def_id: opaque_ty_id, + owner_id: hir::OwnerId { def_id: opaque_ty_id }, ident: Ident::empty(), kind: opaque_ty_item_kind, vis_span: self.lower_span(span.shrink_to_lo()), @@ -1701,62 +1727,38 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { })); let output = if let Some((ret_id, span)) = make_ret_async { - match kind { - FnDeclKind::Trait => { - if !kind.impl_trait_in_trait_allowed(self.tcx) { + if !kind.async_fn_allowed(self.tcx) { + match kind { + FnDeclKind::Trait | FnDeclKind::Impl => { self.tcx .sess .create_feature_err( TraitFnAsync { fn_span, span }, - sym::return_position_impl_trait_in_trait, + sym::async_fn_in_trait, ) .emit(); } - self.lower_async_fn_ret_ty( - &decl.output, - fn_node_id.expect("`make_ret_async` but no `fn_def_id`"), - ret_id, - true, - ) - } - _ => { - if !kind.impl_trait_return_allowed(self.tcx) { - if kind == FnDeclKind::Impl { - self.tcx - .sess - .create_feature_err( - TraitFnAsync { fn_span, span }, - sym::return_position_impl_trait_in_trait, - ) - .emit(); - } else { - self.tcx.sess.emit_err(TraitFnAsync { fn_span, span }); - } + _ => { + self.tcx.sess.emit_err(TraitFnAsync { fn_span, span }); } - self.lower_async_fn_ret_ty( - &decl.output, - fn_node_id.expect("`make_ret_async` but no `fn_def_id`"), - ret_id, - false, - ) } } + + self.lower_async_fn_ret_ty( + &decl.output, + fn_node_id.expect("`make_ret_async` but no `fn_def_id`"), + ret_id, + matches!(kind, FnDeclKind::Trait), + ) } else { match decl.output { FnRetTy::Ty(ref ty) => { let mut context = match fn_node_id { - Some(fn_node_id) if kind.impl_trait_return_allowed(self.tcx) => { - let fn_def_id = self.local_def_id(fn_node_id); - ImplTraitContext::ReturnPositionOpaqueTy { - origin: hir::OpaqueTyOrigin::FnReturn(fn_def_id), - in_trait: false, - } - } - Some(fn_node_id) if kind.impl_trait_in_trait_allowed(self.tcx) => { + Some(fn_node_id) if kind.impl_trait_allowed(self.tcx) => { let fn_def_id = self.local_def_id(fn_node_id); ImplTraitContext::ReturnPositionOpaqueTy { origin: hir::OpaqueTyOrigin::FnReturn(fn_def_id), - in_trait: true, + in_trait: matches!(kind, FnDeclKind::Trait), } } _ => ImplTraitContext::Disallowed(match kind { @@ -1950,9 +1952,13 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { let future_bound = this.lower_async_fn_output_type_to_future_bound( output, span, - ImplTraitContext::ReturnPositionOpaqueTy { - origin: hir::OpaqueTyOrigin::FnReturn(fn_def_id), - in_trait, + if in_trait && !this.tcx.features().return_position_impl_trait_in_trait { + ImplTraitContext::Disallowed(ImplTraitPosition::TraitReturn) + } else { + ImplTraitContext::ReturnPositionOpaqueTy { + origin: hir::OpaqueTyOrigin::FnReturn(fn_def_id), + in_trait, + } }, ); @@ -2038,7 +2044,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { // async fn, so the *type parameters* are inherited. It's // only the lifetime parameters that we must supply. let opaque_ty_ref = hir::TyKind::OpaqueDef( - hir::ItemId { def_id: opaque_ty_def_id }, + hir::ItemId { owner_id: hir::OwnerId { def_id: opaque_ty_def_id } }, generic_args, in_trait, ); |