diff options
Diffstat (limited to 'compiler/rustc_hir_analysis/src/astconv/bounds.rs')
| -rw-r--r-- | compiler/rustc_hir_analysis/src/astconv/bounds.rs | 151 |
1 files changed, 36 insertions, 115 deletions
diff --git a/compiler/rustc_hir_analysis/src/astconv/bounds.rs b/compiler/rustc_hir_analysis/src/astconv/bounds.rs index 3e700f2da..0748644cc 100644 --- a/compiler/rustc_hir_analysis/src/astconv/bounds.rs +++ b/compiler/rustc_hir_analysis/src/astconv/bounds.rs @@ -3,8 +3,7 @@ use rustc_errors::struct_span_err; use rustc_hir as hir; use rustc_hir::def::{DefKind, Res}; use rustc_hir::def_id::{DefId, LocalDefId}; -use rustc_lint_defs::Applicability; -use rustc_middle::ty::{self as ty, Ty, TypeVisitableExt}; +use rustc_middle::ty::{self as ty, Ty}; use rustc_span::symbol::Ident; use rustc_span::{ErrorGuaranteed, Span}; use rustc_trait_selection::traits; @@ -135,17 +134,6 @@ impl<'tcx> dyn AstConv<'tcx> + '_ { only_self_bounds, ); } - &hir::GenericBound::LangItemTrait(lang_item, span, hir_id, args) => { - self.instantiate_lang_item_trait_ref( - lang_item, - span, - hir_id, - args, - param_ty, - bounds, - only_self_bounds, - ); - } hir::GenericBound::Outlives(lifetime) => { let region = self.ast_region_to_region(lifetime, None); bounds.push_region_bound( @@ -194,8 +182,7 @@ impl<'tcx> dyn AstConv<'tcx> + '_ { self.add_bounds( param_ty, - ast_bounds.iter().filter(|bound| { - match filter { + ast_bounds.iter().filter(|bound| match filter { PredicateFilter::All | PredicateFilter::SelfOnly | PredicateFilter::SelfAndAssociatedTypeBounds => true, @@ -209,7 +196,6 @@ impl<'tcx> dyn AstConv<'tcx> + '_ { false } } - } }), &mut bounds, ty::List::empty(), @@ -258,64 +244,49 @@ impl<'tcx> dyn AstConv<'tcx> + '_ { let tcx = self.tcx(); - let return_type_notation = - binding.gen_args.parenthesized == hir::GenericArgsParentheses::ReturnTypeNotation; - - let candidate = if return_type_notation { - if self.trait_defines_associated_item_named( - trait_ref.def_id(), - ty::AssocKind::Fn, - binding.item_name, - ) { - trait_ref + let assoc_kind = + if binding.gen_args.parenthesized == hir::GenericArgsParentheses::ReturnTypeNotation { + ty::AssocKind::Fn + } else if let ConvertedBindingKind::Equality(term) = binding.kind + && let ty::TermKind::Const(_) = term.node.unpack() + { + ty::AssocKind::Const } else { - self.one_bound_for_assoc_method( - traits::supertraits(tcx, trait_ref), - trait_ref.print_only_trait_path(), - binding.item_name, - path_span, - )? - } - } else if self.trait_defines_associated_item_named( + ty::AssocKind::Type + }; + + let candidate = if self.trait_defines_associated_item_named( trait_ref.def_id(), - ty::AssocKind::Type, + assoc_kind, binding.item_name, ) { - // Simple case: X is defined in the current trait. + // Simple case: The assoc item is defined in the current trait. trait_ref } else { // Otherwise, we have to walk through the supertraits to find - // those that do. - self.one_bound_for_assoc_type( + // one that does define it. + self.one_bound_for_assoc_item( || traits::supertraits(tcx, trait_ref), trait_ref.skip_binder().print_only_trait_name(), None, + assoc_kind, binding.item_name, path_span, - match binding.kind { - ConvertedBindingKind::Equality(term) => Some(term), - _ => None, - }, + Some(&binding), )? }; let (assoc_ident, def_scope) = tcx.adjust_ident_and_get_scope(binding.item_name, candidate.def_id(), hir_ref_id); - // We have already adjusted the item name above, so compare with `ident.normalize_to_macros_2_0()` instead - // of calling `filter_by_name_and_kind`. - let find_item_of_kind = |kind| { - tcx.associated_items(candidate.def_id()) - .filter_by_name_unhygienic(assoc_ident.name) - .find(|i| i.kind == kind && i.ident(tcx).normalize_to_macros_2_0() == assoc_ident) - }; - let assoc_item = if return_type_notation { - find_item_of_kind(ty::AssocKind::Fn) - } else { - find_item_of_kind(ty::AssocKind::Type) - .or_else(|| find_item_of_kind(ty::AssocKind::Const)) - } - .expect("missing associated type"); + // We have already adjusted the item name above, so compare with `.normalize_to_macros_2_0()` + // instead of calling `filter_by_name_and_kind` which would needlessly normalize the + // `assoc_ident` again and again. + let assoc_item = tcx + .associated_items(candidate.def_id()) + .filter_by_name_unhygienic(assoc_ident.name) + .find(|i| i.kind == assoc_kind && i.ident(tcx).normalize_to_macros_2_0() == assoc_ident) + .expect("missing associated item"); if !assoc_item.visibility(tcx).is_accessible_from(def_scope, tcx) { tcx.sess @@ -342,7 +313,7 @@ impl<'tcx> dyn AstConv<'tcx> + '_ { .or_insert(binding.span); } - let projection_ty = if return_type_notation { + let projection_ty = if let ty::AssocKind::Fn = assoc_kind { let mut emitted_bad_param_err = false; // If we have an method return type bound, then we need to substitute // the method's early bound params with suitable late-bound params. @@ -350,7 +321,7 @@ impl<'tcx> dyn AstConv<'tcx> + '_ { let args = candidate.skip_binder().args.extend_to(tcx, assoc_item.def_id, |param, _| { let subst = match param.kind { - ty::GenericParamDefKind::Lifetime => ty::Region::new_late_bound( + ty::GenericParamDefKind::Lifetime => ty::Region::new_bound( tcx, ty::INNERMOST, ty::BoundRegion { @@ -469,7 +440,7 @@ impl<'tcx> dyn AstConv<'tcx> + '_ { let late_bound_in_trait_ref = tcx.collect_constrained_late_bound_regions(&projection_ty); let late_bound_in_ty = - tcx.collect_referenced_late_bound_regions(&trait_ref.rebind(ty)); + tcx.collect_referenced_late_bound_regions(&trait_ref.rebind(ty.node)); debug!(?late_bound_in_trait_ref); debug!(?late_bound_in_ty); @@ -494,77 +465,27 @@ impl<'tcx> dyn AstConv<'tcx> + '_ { } } - let assoc_item_def_id = projection_ty.skip_binder().def_id; - let def_kind = tcx.def_kind(assoc_item_def_id); match binding.kind { - ConvertedBindingKind::Equality(..) if return_type_notation => { + ConvertedBindingKind::Equality(..) if let ty::AssocKind::Fn = assoc_kind => { return Err(self.tcx().sess.emit_err( crate::errors::ReturnTypeNotationEqualityBound { span: binding.span }, )); } - ConvertedBindingKind::Equality(mut term) => { + ConvertedBindingKind::Equality(term) => { // "Desugar" a constraint like `T: Iterator<Item = u32>` this to // the "projection predicate" for: // // `<T as Iterator>::Item = u32` - match (def_kind, term.unpack()) { - (DefKind::AssocTy, ty::TermKind::Ty(_)) - | (DefKind::AssocConst, ty::TermKind::Const(_)) => (), - (_, _) => { - let got = if let Some(_) = term.ty() { "type" } else { "constant" }; - let expected = tcx.def_descr(assoc_item_def_id); - let mut err = tcx.sess.struct_span_err( - binding.span, - format!("expected {expected} bound, found {got}"), - ); - err.span_note( - tcx.def_span(assoc_item_def_id), - format!("{expected} defined here"), - ); - - if let DefKind::AssocConst = def_kind - && let Some(t) = term.ty() - && (t.is_enum() || t.references_error()) - && tcx.features().associated_const_equality - { - err.span_suggestion( - binding.span, - "if equating a const, try wrapping with braces", - format!("{} = {{ const }}", binding.item_name), - Applicability::HasPlaceholders, - ); - } - let reported = err.emit(); - term = match def_kind { - DefKind::AssocTy => Ty::new_error(tcx, reported).into(), - DefKind::AssocConst => ty::Const::new_error( - tcx, - reported, - tcx.type_of(assoc_item_def_id) - .instantiate(tcx, projection_ty.skip_binder().args), - ) - .into(), - _ => unreachable!(), - }; - } - } bounds.push_projection_bound( tcx, - projection_ty - .map_bound(|projection_ty| ty::ProjectionPredicate { projection_ty, term }), + projection_ty.map_bound(|projection_ty| ty::ProjectionPredicate { + projection_ty, + term: term.node, + }), binding.span, ); } ConvertedBindingKind::Constraint(ast_bounds) => { - match def_kind { - DefKind::AssocTy => {} - _ => { - return Err(tcx.sess.emit_err(errors::AssocBoundOnConst { - span: assoc_ident.span, - descr: tcx.def_descr(assoc_item_def_id), - })); - } - } // "Desugar" a constraint like `T: Iterator<Item: Debug>` to // // `<T as Iterator>::Item: Debug` |