diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs | 45 |
1 files changed, 21 insertions, 24 deletions
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs index c49621b7c24..2c9d908166f 100644 --- a/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs +++ b/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs @@ -669,6 +669,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { /// This routine checks if the return type is left as default, the method is not part of an /// `impl` block and that it isn't the `main` method. If so, it suggests setting the return /// type. + #[instrument(level = "trace", skip(self, err))] pub(in super::super) fn suggest_missing_return_type( &self, err: &mut Diagnostic, @@ -705,28 +706,24 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { return true } } - hir::FnRetTy::Return(ty) => { - let span = ty.span; - - if let hir::TyKind::OpaqueDef(item_id, ..) = ty.kind - && let hir::Node::Item(hir::Item { - kind: hir::ItemKind::OpaqueTy(op_ty), - .. - }) = self.tcx.hir().get(item_id.hir_id()) - && let hir::OpaqueTy { - bounds: [bound], .. - } = op_ty - && let hir::GenericBound::LangItemTrait( - hir::LangItem::Future, _, _, generic_args) = bound - && let hir::GenericArgs { bindings: [ty_binding], .. } = generic_args - && let hir::TypeBinding { kind, .. } = ty_binding - && let hir::TypeBindingKind::Equality { term } = kind - && let hir::Term::Ty(term_ty) = term { + hir::FnRetTy::Return(hir_ty) => { + let span = hir_ty.span; + + if let hir::TyKind::OpaqueDef(item_id, ..) = hir_ty.kind + && let hir::Node::Item(hir::Item { + kind: hir::ItemKind::OpaqueTy(op_ty), + .. + }) = self.tcx.hir().get(item_id.hir_id()) + && let [hir::GenericBound::LangItemTrait( + hir::LangItem::Future, _, _, generic_args)] = op_ty.bounds + && let hir::GenericArgs { bindings: [ty_binding], .. } = generic_args + && let hir::TypeBindingKind::Equality { term: hir::Term::Ty(term) } = ty_binding.kind + { // Check if async function's return type was omitted. // Don't emit suggestions if the found type is `impl Future<...>`. - debug!("suggest_missing_return_type: found = {:?}", found); + debug!(?found); if found.is_suggestable(self.tcx, false) { - if term_ty.span.is_empty() { + if term.span.is_empty() { err.subdiagnostic(AddReturnTypeSuggestion::Add { span, found: found.to_string() }); return true; } else { @@ -737,11 +734,11 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { // Only point to return type if the expected type is the return type, as if they // are not, the expectation must have been caused by something else. - debug!("suggest_missing_return_type: return type {:?} node {:?}", ty, ty.kind); - let ty = self.astconv().ast_ty_to_ty(ty); - debug!("suggest_missing_return_type: return type {:?}", ty); - debug!("suggest_missing_return_type: expected type {:?}", ty); - let bound_vars = self.tcx.late_bound_vars(fn_id); + debug!("return type {:?}", hir_ty); + let ty = self.astconv().ast_ty_to_ty(hir_ty); + debug!("return type {:?}", ty); + debug!("expected type {:?}", expected); + let bound_vars = self.tcx.late_bound_vars(hir_ty.hir_id.owner.into()); let ty = Binder::bind_with_vars(ty, bound_vars); let ty = self.normalize(span, ty); let ty = self.tcx.erase_late_bound_regions(ty); |