From 7f97dfe700be69d359eaebf97275285f8a85faf4 Mon Sep 17 00:00:00 2001 From: Esteban Küber Date: Thu, 29 Feb 2024 16:30:01 +0000 Subject: Account for unmet `T: !Copy` in E0277 message --- .../src/traits/error_reporting/suggestions.rs | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) (limited to 'compiler/rustc_trait_selection') diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs index e82e94993d2..06f908f01a9 100644 --- a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs +++ b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs @@ -4773,11 +4773,18 @@ pub(super) fn get_explanation_based_on_obligation<'tcx>( Some(desc) => format!(" {desc}"), None => String::new(), }; - format!( - "{pre_message}the trait `{}` is not implemented for{desc} `{}`{post}", - trait_predicate.print_modifiers_and_trait_path(), - tcx.short_ty_string(trait_ref.skip_binder().self_ty(), &mut None), - ) + if let ty::ImplPolarity::Positive = trait_predicate.polarity() { + format!( + "{pre_message}the trait `{}` is not implemented for{desc} `{}`{post}", + trait_predicate.print_modifiers_and_trait_path(), + tcx.short_ty_string(trait_ref.skip_binder().self_ty(), &mut None), + ) + } else { + // "the trait bound `T: !Send` is not satisfied" reads better than "`!Send` is + // not implemented for `T`". + // FIXME: add note explaining explicit negative trait bounds. + format!("{pre_message}the trait bound `{trait_predicate}` is not satisfied{post}") + } } } -- cgit 1.4.1-3-g733a5