diff --git a/compiler/rustc_hir_analysis/messages.ftl b/compiler/rustc_hir_analysis/messages.ftl index e4f225bdad7..703f168b766 100644 --- a/compiler/rustc_hir_analysis/messages.ftl +++ b/compiler/rustc_hir_analysis/messages.ftl @@ -192,7 +192,7 @@ hir_analysis_return_type_notation_equality_bound = return type notation is not allowed to use type equality hir_analysis_return_type_notation_missing_method = - cannot find associated function `{$assoc_name}` in trait `{$trait_name}` + cannot find associated function `{$assoc_name}` for `{$ty_name}` hir_analysis_placeholder_not_allowed_item_signatures = the placeholder `_` is not allowed within types on item signatures for {$kind} .label = not allowed in type signatures diff --git a/compiler/rustc_hir_analysis/src/astconv/mod.rs b/compiler/rustc_hir_analysis/src/astconv/mod.rs index def192f6e10..84c55f12887 100644 --- a/compiler/rustc_hir_analysis/src/astconv/mod.rs +++ b/compiler/rustc_hir_analysis/src/astconv/mod.rs @@ -1118,11 +1118,12 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { ) { trait_ref } else { - return Err(tcx.sess.emit_err(crate::errors::ReturnTypeNotationMissingMethod { - span: binding.span, - trait_name: tcx.item_name(trait_ref.def_id()), - assoc_name: binding.item_name.name, - })); + 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( trait_ref.def_id(), @@ -2057,6 +2058,38 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { Ok(bound) } + #[instrument(level = "debug", skip(self, all_candidates, ty_name), ret)] + fn one_bound_for_assoc_method( + &self, + all_candidates: impl Iterator>, + ty_name: impl Display, + assoc_name: Ident, + span: Span, + ) -> Result, ErrorGuaranteed> { + let mut matching_candidates = all_candidates.filter(|r| { + self.trait_defines_associated_item_named(r.def_id(), ty::AssocKind::Fn, assoc_name) + }); + + let candidate = match matching_candidates.next() { + Some(candidate) => candidate, + None => { + return Err(self.tcx().sess.emit_err( + crate::errors::ReturnTypeNotationMissingMethod { + span, + ty_name: ty_name.to_string(), + assoc_name: assoc_name.name, + }, + )); + } + }; + + if let Some(_conflicting_candidate) = matching_candidates.next() { + todo!() + } + + Ok(candidate) + } + // Create a type from a path to an associated type or to an enum variant. // For a path `A::B::C::D`, `qself_ty` and `qself_def` are the type and def for `A::B::C` // and item_segment is the path segment for `D`. We return a type and a def for diff --git a/compiler/rustc_hir_analysis/src/collect/resolve_bound_vars.rs b/compiler/rustc_hir_analysis/src/collect/resolve_bound_vars.rs index 2e5d058c6ed..44e4e65730e 100644 --- a/compiler/rustc_hir_analysis/src/collect/resolve_bound_vars.rs +++ b/compiler/rustc_hir_analysis/src/collect/resolve_bound_vars.rs @@ -1652,17 +1652,16 @@ impl<'a, 'tcx> BoundVarContext<'a, 'tcx> { if binding.gen_args.parenthesized == hir::GenericArgsParentheses::ReturnTypeNotation { let bound_vars = if let Some(type_def_id) = type_def_id && self.tcx.def_kind(type_def_id) == DefKind::Trait - // FIXME(return_type_notation): We could bound supertrait methods. - && let Some(assoc_fn) = self - .tcx - .associated_items(type_def_id) - .find_by_name_and_kind(self.tcx, binding.ident, ty::AssocKind::Fn, type_def_id) + && let Some((mut bound_vars, assoc_fn)) = + BoundVarContext::supertrait_hrtb_vars( + self.tcx, + type_def_id, + binding.ident, + ty::AssocKind::Fn, + ) { - self.tcx - .generics_of(assoc_fn.def_id) - .params - .iter() - .map(|param| match param.kind { + bound_vars.extend(self.tcx.generics_of(assoc_fn.def_id).params.iter().map( + |param| match param.kind { ty::GenericParamDefKind::Lifetime => ty::BoundVariableKind::Region( ty::BoundRegionKind::BrNamed(param.def_id, param.name), ), @@ -1670,9 +1669,11 @@ impl<'a, 'tcx> BoundVarContext<'a, 'tcx> { ty::BoundTyKind::Param(param.def_id, param.name), ), ty::GenericParamDefKind::Const { .. } => ty::BoundVariableKind::Const, - }) - .chain(self.tcx.fn_sig(assoc_fn.def_id).subst_identity().bound_vars()) - .collect() + }, + )); + bound_vars + .extend(self.tcx.fn_sig(assoc_fn.def_id).subst_identity().bound_vars()); + bound_vars } else { self.tcx.sess.delay_span_bug( binding.ident.span, @@ -1689,8 +1690,13 @@ impl<'a, 'tcx> BoundVarContext<'a, 'tcx> { }); }); } else if let Some(type_def_id) = type_def_id { - let bound_vars = - BoundVarContext::supertrait_hrtb_vars(self.tcx, type_def_id, binding.ident); + let bound_vars = BoundVarContext::supertrait_hrtb_vars( + self.tcx, + type_def_id, + binding.ident, + ty::AssocKind::Type, + ) + .map(|(bound_vars, _)| bound_vars); self.with(scope, |this| { let scope = Scope::Supertrait { bound_vars: bound_vars.unwrap_or_default(), @@ -1720,11 +1726,15 @@ impl<'a, 'tcx> BoundVarContext<'a, 'tcx> { tcx: TyCtxt<'tcx>, def_id: DefId, assoc_name: Ident, - ) -> Option> { + assoc_kind: ty::AssocKind, + ) -> Option<(Vec, &'tcx ty::AssocItem)> { let trait_defines_associated_type_named = |trait_def_id: DefId| { - tcx.associated_items(trait_def_id) - .find_by_name_and_kind(tcx, assoc_name, ty::AssocKind::Type, trait_def_id) - .is_some() + tcx.associated_items(trait_def_id).find_by_name_and_kind( + tcx, + assoc_name, + assoc_kind, + trait_def_id, + ) }; use smallvec::{smallvec, SmallVec}; @@ -1742,8 +1752,8 @@ impl<'a, 'tcx> BoundVarContext<'a, 'tcx> { _ => break None, } - if trait_defines_associated_type_named(def_id) { - break Some(bound_vars.into_iter().collect()); + if let Some(assoc_item) = trait_defines_associated_type_named(def_id) { + break Some((bound_vars.into_iter().collect(), assoc_item)); } let predicates = tcx.super_predicates_that_define_assoc_type((def_id, assoc_name)); let obligations = predicates.predicates.iter().filter_map(|&(pred, _)| { diff --git a/compiler/rustc_hir_analysis/src/errors.rs b/compiler/rustc_hir_analysis/src/errors.rs index 25ad1bed763..48330a94255 100644 --- a/compiler/rustc_hir_analysis/src/errors.rs +++ b/compiler/rustc_hir_analysis/src/errors.rs @@ -512,7 +512,7 @@ pub(crate) struct ReturnTypeNotationEqualityBound { pub(crate) struct ReturnTypeNotationMissingMethod { #[primary_span] pub span: Span, - pub trait_name: Symbol, + pub ty_name: String, pub assoc_name: Symbol, } diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs index a309eaf048d..47972055ae9 100644 --- a/compiler/rustc_middle/src/ty/context.rs +++ b/compiler/rustc_middle/src/ty/context.rs @@ -1570,7 +1570,12 @@ impl<'tcx> TyCtxt<'tcx> { pub fn trait_may_define_assoc_type(self, trait_def_id: DefId, assoc_name: Ident) -> bool { self.super_traits_of(trait_def_id).any(|trait_did| { self.associated_items(trait_did) - .find_by_name_and_kind(self, assoc_name, ty::AssocKind::Type, trait_did) + .find_by_name_and_kinds( + self, + assoc_name, + &[ty::AssocKind::Type, ty::AssocKind::Const, ty::AssocKind::Fn], + trait_did, + ) .is_some() }) } diff --git a/tests/ui/associated-type-bounds/return-type-notation/missing.rs b/tests/ui/associated-type-bounds/return-type-notation/missing.rs index b84b5a717b7..a52562d78f8 100644 --- a/tests/ui/associated-type-bounds/return-type-notation/missing.rs +++ b/tests/ui/associated-type-bounds/return-type-notation/missing.rs @@ -8,6 +8,6 @@ trait Trait { } fn bar>() {} -//~^ ERROR cannot find associated function `methid` in trait `Trait` +//~^ ERROR cannot find associated function `methid` for `Trait` fn main() {} diff --git a/tests/ui/associated-type-bounds/return-type-notation/missing.stderr b/tests/ui/associated-type-bounds/return-type-notation/missing.stderr index 954d9f74767..5b1c4cb0b2c 100644 --- a/tests/ui/associated-type-bounds/return-type-notation/missing.stderr +++ b/tests/ui/associated-type-bounds/return-type-notation/missing.stderr @@ -7,7 +7,7 @@ LL | #![feature(return_type_notation, async_fn_in_trait)] = note: see issue #109417 for more information = note: `#[warn(incomplete_features)]` on by default -error: cannot find associated function `methid` in trait `Trait` +error: cannot find associated function `methid` for `Trait` --> $DIR/missing.rs:10:17 | LL | fn bar>() {} diff --git a/tests/ui/async-await/return-type-notation/super-method-bound.rs b/tests/ui/async-await/return-type-notation/super-method-bound.rs new file mode 100644 index 00000000000..58ea3578db6 --- /dev/null +++ b/tests/ui/async-await/return-type-notation/super-method-bound.rs @@ -0,0 +1,25 @@ +// edition:2021 +// check-pass + +#![feature(async_fn_in_trait, return_type_notation)] +//~^ WARN the feature `return_type_notation` is incomplete + +trait Super<'a> { + async fn test(); +} +impl Super<'_> for () { + async fn test() {} +} + +trait Foo: for<'a> Super<'a> {} +impl Foo for () {} + +fn test() +where + T: Foo, +{ +} + +fn main() { + test::<()>(); +} diff --git a/tests/ui/async-await/return-type-notation/super-method-bound.stderr b/tests/ui/async-await/return-type-notation/super-method-bound.stderr new file mode 100644 index 00000000000..ac0668d3c44 --- /dev/null +++ b/tests/ui/async-await/return-type-notation/super-method-bound.stderr @@ -0,0 +1,11 @@ +warning: the feature `return_type_notation` is incomplete and may not be safe to use and/or cause compiler crashes + --> $DIR/super-method-bound.rs:4:31 + | +LL | #![feature(async_fn_in_trait, return_type_notation)] + | ^^^^^^^^^^^^^^^^^^^^ + | + = note: see issue #109417 for more information + = note: `#[warn(incomplete_features)]` on by default + +warning: 1 warning emitted +