diff options
Diffstat (limited to 'compiler/rustc_borrowck/src/diagnostics/region_errors.rs')
| -rw-r--r-- | compiler/rustc_borrowck/src/diagnostics/region_errors.rs | 104 |
1 files changed, 59 insertions, 45 deletions
diff --git a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs index 187861ba1..ffe82b46c 100644 --- a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs +++ b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs @@ -415,7 +415,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> { /// fn foo<'a, 'b>(x: &'a u32) -> &'b u32 { x } /// ``` /// - /// Here we would be invoked with `fr = 'a` and `outlived_fr = `'b`. + /// Here we would be invoked with `fr = 'a` and `outlived_fr = 'b`. pub(crate) fn report_region_error( &mut self, fr: RegionVid, @@ -575,7 +575,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> { let mut output_ty = self.regioncx.universal_regions().unnormalized_output_ty; if let ty::Alias(ty::Opaque, ty::AliasTy { def_id, .. }) = *output_ty.kind() { - output_ty = self.infcx.tcx.type_of(def_id) + output_ty = self.infcx.tcx.type_of(def_id).subst_identity() }; debug!("report_fnmut_error: output_ty={:?}", output_ty); @@ -583,10 +583,12 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> { let err = FnMutError { span: *span, ty_err: match output_ty.kind() { - ty::Closure(_, _) => FnMutReturnTypeErr::ReturnClosure { span: *span }, ty::Generator(def, ..) if self.infcx.tcx.generator_is_async(*def) => { FnMutReturnTypeErr::ReturnAsyncBlock { span: *span } } + _ if output_ty.contains_closure() => { + FnMutReturnTypeErr::ReturnClosure { span: *span } + } _ => FnMutReturnTypeErr::ReturnRef { span: *span }, }, }; @@ -658,10 +660,8 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> { errci.outlived_fr, ); - let (_, escapes_from) = self - .infcx - .tcx - .article_and_description(self.regioncx.universal_regions().defining_ty.def_id()); + let escapes_from = + self.infcx.tcx.def_descr(self.regioncx.universal_regions().defining_ty.def_id()); // Revert to the normal error in these cases. // Assignments aren't "escapes" in function items. @@ -755,8 +755,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> { .. } = errci; - let (_, mir_def_name) = - self.infcx.tcx.article_and_description(self.mir_def_id().to_def_id()); + let mir_def_name = self.infcx.tcx.def_descr(self.mir_def_id().to_def_id()); let err = LifetimeOutliveErr { span: *span }; let mut diag = self.infcx.tcx.sess.create_err(err); @@ -813,17 +812,10 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> { if *outlived_f != ty::ReStatic { return; } + let suitable_region = self.infcx.tcx.is_suitable_region(f); + let Some(suitable_region) = suitable_region else { return; }; - let fn_returns = self - .infcx - .tcx - .is_suitable_region(f) - .map(|r| self.infcx.tcx.return_type_impl_or_dyn_traits(r.def_id)) - .unwrap_or_default(); - - if fn_returns.is_empty() { - return; - } + let fn_returns = self.infcx.tcx.return_type_impl_or_dyn_traits(suitable_region.def_id); let param = if let Some(param) = find_param_with_region(self.infcx.tcx, f, outlived_f) { param @@ -839,15 +831,43 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> { }; let captures = format!("captures data from {arg}"); - return nice_region_error::suggest_new_region_bound( - self.infcx.tcx, - diag, - fn_returns, - lifetime.to_string(), - Some(arg), - captures, - Some((param.param_ty_span, param.param_ty.to_string())), - self.infcx.tcx.is_suitable_region(f).map(|r| r.def_id), + if !fn_returns.is_empty() { + nice_region_error::suggest_new_region_bound( + self.infcx.tcx, + diag, + fn_returns, + lifetime.to_string(), + Some(arg), + captures, + Some((param.param_ty_span, param.param_ty.to_string())), + Some(suitable_region.def_id), + ); + return; + } + + let Some((alias_tys, alias_span)) = self + .infcx + .tcx + .return_type_impl_or_dyn_traits_with_type_alias(suitable_region.def_id) else { return; }; + + // in case the return type of the method is a type alias + let mut spans_suggs: Vec<_> = Vec::new(); + for alias_ty in alias_tys { + if alias_ty.span.desugaring_kind().is_some() { + // Skip `async` desugaring `impl Future`. + () + } + if let TyKind::TraitObject(_, lt, _) = alias_ty.kind { + spans_suggs.push((lt.ident.span.shrink_to_hi(), " + 'a".to_string())); + } + } + spans_suggs.push((alias_span.shrink_to_hi(), "<'a>".to_string())); + diag.multipart_suggestion_verbose( + &format!( + "to declare that the trait object {captures}, you can add a lifetime parameter `'a` in the type alias" + ), + spans_suggs, + Applicability::MaybeIncorrect, ); } } @@ -873,7 +893,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> { debug!(?fn_did, ?substs); // Only suggest this on function calls, not closures - let ty = tcx.type_of(fn_did); + let ty = tcx.type_of(fn_did).subst_identity(); debug!("ty: {:?}, ty.kind: {:?}", ty, ty.kind()); if let ty::Closure(_, _) = ty.kind() { return; @@ -929,7 +949,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> { .push_span_label(*span, "this has an implicit `'static` lifetime requirement"); multi_span.push_span_label( ident.span, - "calling this method introduces the `impl`'s 'static` requirement", + "calling this method introduces the `impl`'s `'static` requirement", ); err.subdiagnostic(RequireStaticErr::UsedImpl { multi_span }); err.span_suggestion_verbose( @@ -976,7 +996,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> { fn suggest_move_on_borrowing_closure(&self, diag: &mut Diagnostic) { let map = self.infcx.tcx.hir(); let body_id = map.body_owned_by(self.mir_def_id()); - let expr = &map.body(body_id).value; + let expr = &map.body(body_id).value.peel_blocks(); let mut closure_span = None::<rustc_span::Span>; match expr.kind { hir::ExprKind::MethodCall(.., args, _) => { @@ -991,20 +1011,14 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> { } } } - hir::ExprKind::Block(blk, _) => { - if let Some(expr) = blk.expr { - // only when the block is a closure - if let hir::ExprKind::Closure(hir::Closure { - capture_clause: hir::CaptureBy::Ref, - body, - .. - }) = expr.kind - { - let body = map.body(*body); - if !matches!(body.generator_kind, Some(hir::GeneratorKind::Async(..))) { - closure_span = Some(expr.span.shrink_to_lo()); - } - } + hir::ExprKind::Closure(hir::Closure { + capture_clause: hir::CaptureBy::Ref, + body, + .. + }) => { + let body = map.body(*body); + if !matches!(body.generator_kind, Some(hir::GeneratorKind::Async(..))) { + closure_span = Some(expr.span.shrink_to_lo()); } } _ => {} |