diff --git a/compiler/rustc_error_messages/locales/en-US/infer.ftl b/compiler/rustc_error_messages/locales/en-US/infer.ftl index a52ac133946..d28608cf47d 100644 --- a/compiler/rustc_error_messages/locales/en-US/infer.ftl +++ b/compiler/rustc_error_messages/locales/en-US/infer.ftl @@ -211,3 +211,13 @@ infer_trait_placeholder_mismatch = implementation of `{$trait_def_id}` is not ge .label_satisfy = doesn't satisfy where-clause .label_where = due to a where-clause on `{$def_id}`... .label_dup = implementation of `{$trait_def_id}` is not general enough + +infer_trait_impl_diff = `impl` item signature doesn't match `trait` item signature + .found = found `{$found}` + .expected = expected `{$expected}` + .expected_found = expected `{$expected}` + {" "}found `{$found}` + +infer_tid_rel_help = verify the lifetime relationships in the `trait` and `impl` between the `self` argument, the other inputs and its output +infer_tid_consider_borriwing = consider borrowing this type parameter in the trait +infer_tid_param_help = the lifetime requirements from the `impl` do not correspond to the requirements in the `trait` diff --git a/compiler/rustc_infer/src/errors/mod.rs b/compiler/rustc_infer/src/errors/mod.rs index f694c5ca409..e2579ab7b7c 100644 --- a/compiler/rustc_infer/src/errors/mod.rs +++ b/compiler/rustc_infer/src/errors/mod.rs @@ -581,3 +581,41 @@ pub struct TraitPlaceholderMismatch { #[subdiagnostic] pub actual_impl_expl_notes: Vec, } + +pub struct ConsiderBorrowingParamHelp { + pub spans: Vec, +} + +impl AddSubdiagnostic for ConsiderBorrowingParamHelp { + fn add_to_diagnostic(self, diag: &mut rustc_errors::Diagnostic) { + let mut type_param_span: MultiSpan = self.spans.clone().into(); + for &span in &self.spans { + type_param_span.push_span_label(span, fluent::infer::tid_consider_borriwing); + } + diag.span_help(type_param_span, fluent::infer::tid_param_help); + } +} + +#[derive(SessionSubdiagnostic)] +#[help(infer::tid_rel_help)] +pub struct RelationshipHelp; + +#[derive(SessionDiagnostic)] +#[diag(infer::trait_impl_diff)] +pub struct TraitImplDiff { + #[primary_span] + #[label(infer::found)] + pub sp: Span, + #[label(infer::expected)] + pub trait_sp: Span, + #[note(infer::expected_found)] + pub note: (), + #[subdiagnostic] + pub param_help: ConsiderBorrowingParamHelp, + #[subdiagnostic] + // Seems like subdiagnostics are always pushed to the end, so this one + // also has to be a subdiagnostic to maintain order. + pub rel_help: Option, + pub expected: String, + pub found: String, +} diff --git a/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/trait_impl_difference.rs b/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/trait_impl_difference.rs index 5d536e982ed..bacd8894a0f 100644 --- a/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/trait_impl_difference.rs +++ b/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/trait_impl_difference.rs @@ -1,10 +1,11 @@ //! Error Reporting for `impl` items that do not match the obligations from their `trait`. +use crate::errors::{ConsiderBorrowingParamHelp, RelationshipHelp, TraitImplDiff}; use crate::infer::error_reporting::nice_region_error::NiceRegionError; use crate::infer::lexical_region_resolve::RegionResolutionError; use crate::infer::Subtype; use crate::traits::ObligationCauseCode::CompareImplItemObligation; -use rustc_errors::{ErrorGuaranteed, MultiSpan}; +use rustc_errors::ErrorGuaranteed; use rustc_hir as hir; use rustc_hir::def::Res; use rustc_hir::def_id::DefId; @@ -51,10 +52,6 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> { trait_def_id: DefId, ) -> ErrorGuaranteed { let trait_sp = self.tcx().def_span(trait_def_id); - let mut err = self - .tcx() - .sess - .struct_span_err(sp, "`impl` item signature doesn't match `trait` item signature"); // Mark all unnamed regions in the type with a number. // This diagnostic is called in response to lifetime errors, so be informative. @@ -91,9 +88,6 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> { let found = self.cx.extract_inference_diagnostics_data(found.into(), Some(found_highlight)).name; - err.span_label(sp, &format!("found `{}`", found)); - err.span_label(trait_sp, &format!("expected `{}`", expected)); - // Get the span of all the used type parameters in the method. let assoc_item = self.tcx().associated_item(trait_def_id); let mut visitor = TypeParamSpanVisitor { tcx: self.tcx(), types: vec![] }; @@ -110,26 +104,18 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> { } _ => {} } - let mut type_param_span: MultiSpan = visitor.types.to_vec().into(); - for &span in &visitor.types { - type_param_span - .push_span_label(span, "consider borrowing this type parameter in the trait"); - } - err.note(&format!("expected `{}`\n found `{}`", expected, found)); + let diag = TraitImplDiff { + sp, + trait_sp, + note: (), + param_help: ConsiderBorrowingParamHelp { spans: visitor.types.to_vec() }, + rel_help: visitor.types.is_empty().then_some(RelationshipHelp), + expected, + found, + }; - err.span_help( - type_param_span, - "the lifetime requirements from the `impl` do not correspond to the requirements in \ - the `trait`", - ); - if visitor.types.is_empty() { - err.help( - "verify the lifetime relationships in the `trait` and `impl` between the `self` \ - argument, the other inputs and its output", - ); - } - err.emit() + self.tcx().sess.emit_err(diag) } }