From 70fe624b3d82aee2d32908f3fe2216002a207846 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Esteban=20K=C3=BCber?= Date: Sat, 7 Oct 2023 03:58:45 +0000 Subject: [PATCH] Reduce verbosity of error --- .../error_reporting/type_err_ctxt_ext.rs | 37 +++++++++++-------- .../question-mark-result-err-mismatch.rs | 6 +-- .../question-mark-result-err-mismatch.stderr | 24 +----------- 3 files changed, 24 insertions(+), 43 deletions(-) diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs index 5f522fc29eb28..a779d69943ddf 100644 --- a/compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs +++ b/compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs @@ -112,7 +112,7 @@ pub trait TypeErrCtxtExt<'tcx> { obligation: &PredicateObligation<'tcx>, trait_ref: ty::TraitRef<'tcx>, err: &mut Diagnostic, - ); + ) -> bool; fn report_const_param_not_wf( &self, @@ -517,8 +517,9 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> { let mut err = struct_span_err!(self.tcx.sess, span, E0277, "{}", err_msg); + let mut suggested = false; if is_try_conversion { - self.try_conversion_context(&obligation, trait_ref.skip_binder(), &mut err); + suggested = self.try_conversion_context(&obligation, trait_ref.skip_binder(), &mut err); } if is_try_conversion && let Some(ret_span) = self.return_type_span(&obligation) { @@ -621,8 +622,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> { self.suggest_floating_point_literal(&obligation, &mut err, &trait_ref); self.suggest_dereferencing_index(&obligation, &mut err, trait_predicate); - let mut suggested = - self.suggest_dereferences(&obligation, &mut err, trait_predicate); + suggested |= self.suggest_dereferences(&obligation, &mut err, trait_predicate); suggested |= self.suggest_fn_call(&obligation, &mut err, trait_predicate); let impl_candidates = self.find_similar_impl_candidates(trait_predicate); suggested = if let &[cand] = &impl_candidates[..] { @@ -1002,7 +1002,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> { obligation: &PredicateObligation<'tcx>, trait_ref: ty::TraitRef<'tcx>, err: &mut Diagnostic, - ) { + ) -> bool { let span = obligation.cause.span; struct V<'v> { search_span: Span, @@ -1027,22 +1027,22 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> { Some(hir::Node::Item(hir::Item { kind: hir::ItemKind::Fn(_, _, body_id), .. })) => { body_id } - _ => return, + _ => return false, }; let mut v = V { search_span: span, found: None }; v.visit_body(self.tcx.hir().body(*body_id)); let Some(expr) = v.found else { - return; + return false; }; let Some(typeck) = &self.typeck_results else { - return; + return false; }; let Some((ObligationCauseCode::QuestionMark, Some(y))) = obligation.cause.code().parent() else { - return; + return false; }; if !self.tcx.is_diagnostic_item(sym::FromResidual, y.def_id()) { - return; + return false; } let self_ty = trait_ref.self_ty(); let found_ty = trait_ref.args.get(1).and_then(|a| a.as_type()); @@ -1067,6 +1067,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> { Some(arg.as_type()?) }; + let mut suggested = false; let mut chain = vec![]; // The following logic is simlar to `point_at_chain`, but that's focused on associated types @@ -1135,6 +1136,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> { ) .must_apply_modulo_regions() { + suggested = true; err.span_suggestion_short( stmt.span.with_lo(expr.span.hi()), "remove this semicolon", @@ -1193,17 +1195,20 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> { ) .must_apply_modulo_regions() { - err.span_label(span, format!("this has type `Result<_, {err_ty}>`")); + if !suggested { + err.span_label(span, format!("this has type `Result<_, {err_ty}>`")); + } } else { err.span_label( - span, - format!( - "this can't be annotated with `?` because it has type `Result<_, {err_ty}>`", - ), - ); + span, + format!( + "this can't be annotated with `?` because it has type `Result<_, {err_ty}>`", + ), + ); } prev = Some(err_ty); } + suggested } fn report_const_param_not_wf( diff --git a/tests/ui/traits/question-mark-result-err-mismatch.rs b/tests/ui/traits/question-mark-result-err-mismatch.rs index 317029e004613..0ca18b5b0ddce 100644 --- a/tests/ui/traits/question-mark-result-err-mismatch.rs +++ b/tests/ui/traits/question-mark-result-err-mismatch.rs @@ -3,7 +3,7 @@ fn foo() -> Result { //~ NOTE expected `String` because of this let x = test .split_whitespace() .next() - .ok_or_else(|| { //~ NOTE this has type `Result<_, &str>` + .ok_or_else(|| { "Couldn't split the test string" }); let one = x @@ -15,11 +15,9 @@ fn foo() -> Result { //~ NOTE expected `String` because of this //~^ NOTE in this expansion of desugaring of operator `?` //~| NOTE in this expansion of desugaring of operator `?` //~| NOTE in this expansion of desugaring of operator `?` - //~| NOTE in this expansion of desugaring of operator `?` //~| NOTE the trait `From<()>` is not implemented for `String` //~| NOTE the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait //~| NOTE required for `Result` to implement `FromResidual>` - //~| HELP the following other types implement trait `From`: Ok(one.to_string()) } @@ -52,11 +50,9 @@ fn baz() -> Result { //~ NOTE expected `String` because of this //~| NOTE in this expansion of desugaring of operator `?` //~| NOTE in this expansion of desugaring of operator `?` //~| NOTE in this expansion of desugaring of operator `?` - //~| NOTE in this expansion of desugaring of operator `?` //~| NOTE the trait `From<()>` is not implemented for `String` //~| NOTE the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait //~| NOTE required for `Result` to implement `FromResidual>` - //~| HELP the following other types implement trait `From`: Ok(one.to_string()) } diff --git a/tests/ui/traits/question-mark-result-err-mismatch.stderr b/tests/ui/traits/question-mark-result-err-mismatch.stderr index 1f9495a505ac3..3059e0beca3e4 100644 --- a/tests/ui/traits/question-mark-result-err-mismatch.stderr +++ b/tests/ui/traits/question-mark-result-err-mismatch.stderr @@ -4,12 +4,6 @@ error[E0277]: `?` couldn't convert the error to `String` LL | fn foo() -> Result { | ---------------------- expected `String` because of this ... -LL | .ok_or_else(|| { - | __________- -LL | | "Couldn't split the test string" -LL | | }); - | |__________- this has type `Result<_, &str>` -... LL | .map_err(|e| { | __________- LL | | e; @@ -20,17 +14,10 @@ LL | .map(|()| "")?; | ^ the trait `From<()>` is not implemented for `String` | = note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait - = help: the following other types implement trait `From`: - > - >> - >> - > - > - > = note: required for `Result` to implement `FromResidual>` error[E0277]: `?` couldn't convert the error to `String` - --> $DIR/question-mark-result-err-mismatch.rs:30:25 + --> $DIR/question-mark-result-err-mismatch.rs:28:25 | LL | fn bar() -> Result<(), String> { | ------------------ expected `String` because of this @@ -53,7 +40,7 @@ LL | .map_err(|_| ())?; = note: required for `Result<(), String>` to implement `FromResidual>` error[E0277]: `?` couldn't convert the error to `String` - --> $DIR/question-mark-result-err-mismatch.rs:50:11 + --> $DIR/question-mark-result-err-mismatch.rs:48:11 | LL | fn baz() -> Result { | ---------------------- expected `String` because of this @@ -68,13 +55,6 @@ LL | | })?; | this can't be annotated with `?` because it has type `Result<_, ()>` | = note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait - = help: the following other types implement trait `From`: - > - >> - >> - > - > - > = note: required for `Result` to implement `FromResidual>` error: aborting due to 3 previous errors