diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/rustc_errors/src/diagnostic.rs | 2 | ||||
| -rw-r--r-- | compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs | 228 |
2 files changed, 126 insertions, 104 deletions
diff --git a/compiler/rustc_errors/src/diagnostic.rs b/compiler/rustc_errors/src/diagnostic.rs index 5746c28a2ab..a128f8d31a1 100644 --- a/compiler/rustc_errors/src/diagnostic.rs +++ b/compiler/rustc_errors/src/diagnostic.rs @@ -1165,7 +1165,7 @@ impl<'a, G: EmissionGuarantee> Diag<'a, G> { self.push_suggestion(CodeSuggestion { substitutions, msg: self.subdiagnostic_message_to_diagnostic_message(msg), - style: SuggestionStyle::ShowCode, + style: SuggestionStyle::ShowAlways, applicability, }); self diff --git a/compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs b/compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs index 3e64573aa03..8c9eb41568f 100644 --- a/compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs +++ b/compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs @@ -1321,7 +1321,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> { let imm_ref_self_ty_satisfies_pred = mk_result(trait_pred_and_imm_ref); let mut_ref_self_ty_satisfies_pred = mk_result(trait_pred_and_mut_ref); - let (ref_inner_ty_satisfies_pred, ref_inner_ty_mut) = + let (ref_inner_ty_satisfies_pred, ref_inner_ty_is_mut) = if let ObligationCauseCode::WhereClauseInExpr(..) = obligation.cause.code() && let ty::Ref(_, ty, mutability) = old_pred.self_ty().skip_binder().kind() { @@ -1333,117 +1333,139 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> { (false, false) }; - if imm_ref_self_ty_satisfies_pred - || mut_ref_self_ty_satisfies_pred - || ref_inner_ty_satisfies_pred - { - if let Ok(snippet) = self.tcx.sess.source_map().span_to_snippet(span) { - // We don't want a borrowing suggestion on the fields in structs, - // ``` - // struct Foo { - // the_foos: Vec<Foo> - // } - // ``` - if !matches!( - span.ctxt().outer_expn_data().kind, - ExpnKind::Root | ExpnKind::Desugaring(DesugaringKind::ForLoop) - ) { - return false; - } - if snippet.starts_with('&') { - // This is already a literal borrow and the obligation is failing - // somewhere else in the obligation chain. Do not suggest non-sense. - return false; - } - // We have a very specific type of error, where just borrowing this argument - // might solve the problem. In cases like this, the important part is the - // original type obligation, not the last one that failed, which is arbitrary. - // Because of this, we modify the error to refer to the original obligation and - // return early in the caller. - - let msg = format!( - "the trait bound `{}` is not satisfied", - self.tcx.short_string(old_pred, err.long_ty_path()), - ); - let self_ty_str = - self.tcx.short_string(old_pred.self_ty().skip_binder(), err.long_ty_path()); - if has_custom_message { - err.note(msg); - } else { - err.messages = vec![(rustc_errors::DiagMessage::from(msg), Style::NoStyle)]; - } - err.span_label( - span, - format!( - "the trait `{}` is not implemented for `{self_ty_str}`", - old_pred.print_modifiers_and_trait_path() - ), - ); + let is_immut = imm_ref_self_ty_satisfies_pred + || (ref_inner_ty_satisfies_pred && !ref_inner_ty_is_mut); + let is_mut = mut_ref_self_ty_satisfies_pred || ref_inner_ty_is_mut; + if !is_immut && !is_mut { + return false; + } + let Ok(_snippet) = self.tcx.sess.source_map().span_to_snippet(span) else { + return false; + }; + // We don't want a borrowing suggestion on the fields in structs + // ``` + // #[derive(Clone)] + // struct Foo { + // the_foos: Vec<Foo> + // } + // ``` + if !matches!( + span.ctxt().outer_expn_data().kind, + ExpnKind::Root | ExpnKind::Desugaring(DesugaringKind::ForLoop) + ) { + return false; + } + // We have a very specific type of error, where just borrowing this argument + // might solve the problem. In cases like this, the important part is the + // original type obligation, not the last one that failed, which is arbitrary. + // Because of this, we modify the error to refer to the original obligation and + // return early in the caller. - if imm_ref_self_ty_satisfies_pred && mut_ref_self_ty_satisfies_pred { - err.span_suggestions( - span.shrink_to_lo(), - "consider borrowing here", - ["&".to_string(), "&mut ".to_string()], - Applicability::MaybeIncorrect, - ); - } else { - let is_mut = mut_ref_self_ty_satisfies_pred || ref_inner_ty_mut; - let sugg_prefix = format!("&{}", if is_mut { "mut " } else { "" }); - let sugg_msg = format!( - "consider{} borrowing here", - if is_mut { " mutably" } else { "" } - ); + let mut label = || { + let msg = format!( + "the trait bound `{}` is not satisfied", + self.tcx.short_string(old_pred, err.long_ty_path()), + ); + let self_ty_str = + self.tcx.short_string(old_pred.self_ty().skip_binder(), err.long_ty_path()); + if has_custom_message { + err.note(msg); + } else { + err.messages = vec![(rustc_errors::DiagMessage::from(msg), Style::NoStyle)]; + } + err.span_label( + span, + format!( + "the trait `{}` is not implemented for `{self_ty_str}`", + old_pred.print_modifiers_and_trait_path() + ), + ); + }; - // Issue #109436, we need to add parentheses properly for method calls - // for example, `foo.into()` should be `(&foo).into()` - if let Some(_) = - self.tcx.sess.source_map().span_look_ahead(span, ".", Some(50)) - { - err.multipart_suggestion_verbose( - sugg_msg, - vec![ - (span.shrink_to_lo(), format!("({sugg_prefix}")), - (span.shrink_to_hi(), ")".to_string()), - ], - Applicability::MaybeIncorrect, - ); - return true; - } + let mut sugg_prefixes = vec![]; + if is_immut { + sugg_prefixes.push("&"); + } + if is_mut { + sugg_prefixes.push("&mut "); + } + let sugg_msg = format!( + "consider{} borrowing here", + if is_mut && !is_immut { " mutably" } else { "" }, + ); - // Issue #104961, we need to add parentheses properly for compound expressions - // for example, `x.starts_with("hi".to_string() + "you")` - // should be `x.starts_with(&("hi".to_string() + "you"))` - let Some(body) = self.tcx.hir_maybe_body_owned_by(obligation.cause.body_id) - else { - return false; - }; - let mut expr_finder = FindExprBySpan::new(span, self.tcx); - expr_finder.visit_expr(body.value); - let Some(expr) = expr_finder.result else { - return false; - }; - let needs_parens = expr_needs_parens(expr); + // Issue #104961, we need to add parentheses properly for compound expressions + // for example, `x.starts_with("hi".to_string() + "you")` + // should be `x.starts_with(&("hi".to_string() + "you"))` + let Some(body) = self.tcx.hir_maybe_body_owned_by(obligation.cause.body_id) else { + return false; + }; + let mut expr_finder = FindExprBySpan::new(span, self.tcx); + expr_finder.visit_expr(body.value); - let span = if needs_parens { span } else { span.shrink_to_lo() }; - let suggestions = if !needs_parens { - vec![(span.shrink_to_lo(), sugg_prefix)] - } else { + if let Some(ty) = expr_finder.ty_result { + if let hir::Node::Expr(expr) = self.tcx.parent_hir_node(ty.hir_id) + && let hir::ExprKind::Path(hir::QPath::TypeRelative(_, _)) = expr.kind + && ty.span == span + { + // We've encountered something like `str::from("")`, where the intended code + // was likely `<&str>::from("")`. #143393. + label(); + err.multipart_suggestions( + sugg_msg, + sugg_prefixes.into_iter().map(|sugg_prefix| { vec![ - (span.shrink_to_lo(), format!("{sugg_prefix}(")), - (span.shrink_to_hi(), ")".to_string()), + (span.shrink_to_lo(), format!("<{sugg_prefix}")), + (span.shrink_to_hi(), ">".to_string()), ] - }; - err.multipart_suggestion_verbose( - sugg_msg, - suggestions, - Applicability::MaybeIncorrect, - ); - } + }), + Applicability::MaybeIncorrect, + ); return true; } + return false; } - return false; + let Some(expr) = expr_finder.result else { + return false; + }; + if let hir::ExprKind::AddrOf(_, _, _) = expr.kind { + return false; + } + let needs_parens_post = expr_needs_parens(expr); + let needs_parens_pre = match self.tcx.parent_hir_node(expr.hir_id) { + Node::Expr(e) + if let hir::ExprKind::MethodCall(_, base, _, _) = e.kind + && base.hir_id == expr.hir_id => + { + true + } + _ => false, + }; + + label(); + let suggestions = sugg_prefixes.into_iter().map(|sugg_prefix| { + match (needs_parens_pre, needs_parens_post) { + (false, false) => vec![(span.shrink_to_lo(), sugg_prefix.to_string())], + // We have something like `foo.bar()`, where we want to bororw foo, so we need + // to suggest `(&mut foo).bar()`. + (false, true) => vec![ + (span.shrink_to_lo(), format!("{sugg_prefix}(")), + (span.shrink_to_hi(), ")".to_string()), + ], + // Issue #109436, we need to add parentheses properly for method calls + // for example, `foo.into()` should be `(&foo).into()` + (true, false) => vec![ + (span.shrink_to_lo(), format!("({sugg_prefix}")), + (span.shrink_to_hi(), ")".to_string()), + ], + (true, true) => vec![ + (span.shrink_to_lo(), format!("({sugg_prefix}(")), + (span.shrink_to_hi(), "))".to_string()), + ], + } + }); + err.multipart_suggestions(sugg_msg, suggestions, Applicability::MaybeIncorrect); + return true; }; if let ObligationCauseCode::ImplDerived(cause) = &*code { |