diff options
Diffstat (limited to 'compiler/rustc_infer/src/infer/error_reporting/suggest.rs')
| -rw-r--r-- | compiler/rustc_infer/src/infer/error_reporting/suggest.rs | 217 |
1 files changed, 100 insertions, 117 deletions
diff --git a/compiler/rustc_infer/src/infer/error_reporting/suggest.rs b/compiler/rustc_infer/src/infer/error_reporting/suggest.rs index 55dcfd05e..b5aeca12a 100644 --- a/compiler/rustc_infer/src/infer/error_reporting/suggest.rs +++ b/compiler/rustc_infer/src/infer/error_reporting/suggest.rs @@ -1,7 +1,7 @@ use hir::def::CtorKind; use hir::intravisit::{walk_expr, walk_stmt, Visitor}; use rustc_data_structures::fx::FxIndexSet; -use rustc_errors::{Applicability, Diagnostic}; +use rustc_errors::Diagnostic; use rustc_hir as hir; use rustc_middle::traits::{ IfExpressionCause, MatchExpressionArmCause, ObligationCause, ObligationCauseCode, @@ -10,13 +10,23 @@ use rustc_middle::traits::{ use rustc_middle::ty::print::with_no_trimmed_paths; use rustc_middle::ty::{self as ty, IsSuggestable, Ty, TypeVisitableExt}; use rustc_span::{sym, BytePos, Span}; +use rustc_target::abi::FieldIdx; use crate::errors::{ - ConsiderAddingAwait, SuggAddLetForLetChains, SuggestRemoveSemiOrReturnBinding, + ConsiderAddingAwait, FnConsiderCasting, FnItemsAreDistinct, FnUniqTypes, + FunctionPointerSuggestion, SuggestAccessingField, SuggestAsRefWhereAppropriate, + SuggestBoxingForReturnImplTrait, SuggestRemoveSemiOrReturnBinding, SuggestTuplePatternMany, + SuggestTuplePatternOne, TypeErrorAdditionalDiags, }; use super::TypeErrCtxt; +#[derive(Clone, Copy)] +pub enum SuggestAsRefKind { + Option, + Result, +} + impl<'tcx> TypeErrCtxt<'_, 'tcx> { pub(super) fn suggest_remove_semi_or_return_binding( &self, @@ -71,25 +81,20 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { return_sp: Span, arm_spans: impl Iterator<Item = Span>, ) { - err.multipart_suggestion( - "you could change the return type to be a boxed trait object", - vec![ - (return_sp.with_hi(return_sp.lo() + BytePos(4)), "Box<dyn".to_string()), - (return_sp.shrink_to_hi(), ">".to_string()), - ], - Applicability::MaybeIncorrect, - ); - let sugg = arm_spans - .flat_map(|sp| { - [(sp.shrink_to_lo(), "Box::new(".to_string()), (sp.shrink_to_hi(), ")".to_string())] - .into_iter() - }) - .collect::<Vec<_>>(); - err.multipart_suggestion( - "if you change the return type to expect trait objects, box the returned expressions", - sugg, - Applicability::MaybeIncorrect, - ); + let sugg = SuggestBoxingForReturnImplTrait::ChangeReturnType { + start_sp: return_sp.with_hi(return_sp.lo() + BytePos(4)), + end_sp: return_sp.shrink_to_hi(), + }; + err.subdiagnostic(sugg); + + let mut starts = Vec::new(); + let mut ends = Vec::new(); + for span in arm_spans { + starts.push(span.shrink_to_lo()); + ends.push(span.shrink_to_hi()); + } + let sugg = SuggestBoxingForReturnImplTrait::BoxReturnExpr { starts, ends }; + err.subdiagnostic(sugg); } pub(super) fn suggest_tuple_pattern( @@ -109,7 +114,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { variant.fields.len() == 1 && variant.ctor_kind() == Some(CtorKind::Fn) }) .filter_map(|variant| { - let sole_field = &variant.fields[0]; + let sole_field = &variant.fields[FieldIdx::from_u32(0)]; let sole_field_ty = sole_field.ty(self.tcx, substs); if self.same_type_modulo_infer(sole_field_ty, exp_found.found) { let variant_path = @@ -129,30 +134,21 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { match &compatible_variants[..] { [] => {} [variant] => { - diag.multipart_suggestion_verbose( - &format!("try wrapping the pattern in `{}`", variant), - vec![ - (cause.span.shrink_to_lo(), format!("{}(", variant)), - (cause.span.shrink_to_hi(), ")".to_string()), - ], - Applicability::MaybeIncorrect, - ); + let sugg = SuggestTuplePatternOne { + variant: variant.to_owned(), + span_low: cause.span.shrink_to_lo(), + span_high: cause.span.shrink_to_hi(), + }; + diag.subdiagnostic(sugg); } _ => { // More than one matching variant. - diag.multipart_suggestions( - &format!( - "try wrapping the pattern in a variant of `{}`", - self.tcx.def_path_str(expected_adt.did()) - ), - compatible_variants.into_iter().map(|variant| { - vec![ - (cause.span.shrink_to_lo(), format!("{}(", variant)), - (cause.span.shrink_to_hi(), ")".to_string()), - ] - }), - Applicability::MaybeIncorrect, - ); + let sugg = SuggestTuplePatternMany { + path: self.tcx.def_path_str(expected_adt.did()), + cause_span: cause.span, + compatible_variants, + }; + diag.subdiagnostic(sugg); } } } @@ -255,15 +251,6 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { } } - pub fn suggest_await_on_future(&self, diag: &mut Diagnostic, sp: Span) { - diag.span_suggestion_verbose( - sp.shrink_to_hi(), - "consider `await`ing on the `Future`", - ".await", - Applicability::MaybeIncorrect, - ); - } - pub(super) fn suggest_accessing_field_where_appropriate( &self, cause: &ObligationCause<'tcx>, @@ -290,21 +277,13 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { if let ObligationCauseCode::Pattern { span: Some(span), .. } = *cause.code() { if let Ok(snippet) = self.tcx.sess.source_map().span_to_snippet(span) { let suggestion = if expected_def.is_struct() { - format!("{}.{}", snippet, name) + SuggestAccessingField::Safe { span, snippet, name, ty } } else if expected_def.is_union() { - format!("unsafe {{ {}.{} }}", snippet, name) + SuggestAccessingField::Unsafe { span, snippet, name, ty } } else { return; }; - diag.span_suggestion( - span, - &format!( - "you might have meant to use field `{}` whose type is `{}`", - name, ty - ), - suggestion, - Applicability::MaybeIncorrect, - ); + diag.subdiagnostic(suggestion); } } } @@ -320,15 +299,15 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { diag: &mut Diagnostic, ) { if let Ok(snippet) = self.tcx.sess.source_map().span_to_snippet(span) - && let Some(msg) = self.should_suggest_as_ref(exp_found.expected, exp_found.found) + && let Some(msg) = self.should_suggest_as_ref_kind(exp_found.expected, exp_found.found) { - diag.span_suggestion( - span, - msg, - // HACK: fix issue# 100605, suggesting convert from &Option<T> to Option<&T>, remove the extra `&` - format!("{}.as_ref()", snippet.trim_start_matches('&')), - Applicability::MachineApplicable, - ); + // HACK: fix issue# 100605, suggesting convert from &Option<T> to Option<&T>, remove the extra `&` + let snippet = snippet.trim_start_matches('&'); + let subdiag = match msg { + SuggestAsRefKind::Option => SuggestAsRefWhereAppropriate::Option { span, snippet }, + SuggestAsRefKind::Result => SuggestAsRefWhereAppropriate::Result { span, snippet }, + }; + diag.subdiagnostic(subdiag); } } @@ -356,36 +335,24 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { if !self.same_type_modulo_infer(*found_sig, *expected_sig) || !sig.is_suggestable(self.tcx, true) - || ty::util::is_intrinsic(self.tcx, *did) + || self.tcx.is_intrinsic(*did) { return; } - let (msg, sug) = match (expected.is_ref(), found.is_ref()) { - (true, false) => { - let msg = "consider using a reference"; - let sug = format!("&{fn_name}"); - (msg, sug) - } - (false, true) => { - let msg = "consider removing the reference"; - let sug = format!("{fn_name}"); - (msg, sug) - } + let sugg = match (expected.is_ref(), found.is_ref()) { + (true, false) => FunctionPointerSuggestion::UseRef { span, fn_name }, + (false, true) => FunctionPointerSuggestion::RemoveRef { span, fn_name }, (true, true) => { - diag.note("fn items are distinct from fn pointers"); - let msg = "consider casting to a fn pointer"; - let sug = format!("&({fn_name} as {sig})"); - (msg, sug) + diag.subdiagnostic(FnItemsAreDistinct); + FunctionPointerSuggestion::CastRef { span, fn_name, sig: *sig } } (false, false) => { - diag.note("fn items are distinct from fn pointers"); - let msg = "consider casting to a fn pointer"; - let sug = format!("{fn_name} as {sig}"); - (msg, sug) + diag.subdiagnostic(FnItemsAreDistinct); + FunctionPointerSuggestion::Cast { span, fn_name, sig: *sig } } }; - diag.span_suggestion_verbose(span, msg, sug, Applicability::MaybeIncorrect); + diag.subdiagnostic(sugg); } (ty::FnDef(did1, substs1), ty::FnDef(did2, substs2)) => { let expected_sig = @@ -394,30 +361,36 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { &(self.normalize_fn_sig)(self.tcx.fn_sig(*did2).subst(self.tcx, substs2)); if self.same_type_modulo_infer(*expected_sig, *found_sig) { - diag.note("different fn items have unique types, even if their signatures are the same"); + diag.subdiagnostic(FnUniqTypes); } if !self.same_type_modulo_infer(*found_sig, *expected_sig) || !found_sig.is_suggestable(self.tcx, true) || !expected_sig.is_suggestable(self.tcx, true) - || ty::util::is_intrinsic(self.tcx, *did1) - || ty::util::is_intrinsic(self.tcx, *did2) + || self.tcx.is_intrinsic(*did1) + || self.tcx.is_intrinsic(*did2) { return; } let fn_name = self.tcx.def_path_str_with_substs(*did2, substs2); let sug = if found.is_ref() { - format!("&({fn_name} as {found_sig})") + FunctionPointerSuggestion::CastBothRef { + span, + fn_name, + found_sig: *found_sig, + expected_sig: *expected_sig, + } } else { - format!("{fn_name} as {found_sig}") + FunctionPointerSuggestion::CastBoth { + span, + fn_name, + found_sig: *found_sig, + expected_sig: *expected_sig, + } }; - let msg = format!( - "consider casting both fn items to fn pointers using `as {expected_sig}`" - ); - - diag.span_suggestion_hidden(span, msg, sug, Applicability::MaybeIncorrect); + diag.subdiagnostic(sug); } (ty::FnDef(did, substs), ty::FnPtr(sig)) => { let expected_sig = @@ -436,7 +409,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { format!("{fn_name} as {found_sig}") }; - diag.help(&format!("consider casting the fn item to a fn pointer: `{}`", casting)); + diag.subdiagnostic(FnConsiderCasting { casting }); } _ => { return; @@ -444,23 +417,19 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { }; } - pub fn should_suggest_as_ref(&self, expected: Ty<'tcx>, found: Ty<'tcx>) -> Option<&str> { + pub fn should_suggest_as_ref_kind( + &self, + expected: Ty<'tcx>, + found: Ty<'tcx>, + ) -> Option<SuggestAsRefKind> { if let (ty::Adt(exp_def, exp_substs), ty::Ref(_, found_ty, _)) = (expected.kind(), found.kind()) { if let ty::Adt(found_def, found_substs) = *found_ty.kind() { if exp_def == &found_def { let have_as_ref = &[ - ( - sym::Option, - "you can convert from `&Option<T>` to `Option<&T>` using \ - `.as_ref()`", - ), - ( - sym::Result, - "you can convert from `&Result<T, E>` to \ - `Result<&T, &E>` using `.as_ref()`", - ), + (sym::Option, SuggestAsRefKind::Option), + (sym::Result, SuggestAsRefKind::Result), ]; if let Some(msg) = have_as_ref.iter().find_map(|(name, msg)| { self.tcx.is_diagnostic_item(*name, exp_def.did()).then_some(msg) @@ -494,15 +463,28 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { None } + // FIXME: Remove once `rustc_hir_typeck` is migrated to diagnostic structs + pub fn should_suggest_as_ref(&self, expected: Ty<'tcx>, found: Ty<'tcx>) -> Option<&str> { + match self.should_suggest_as_ref_kind(expected, found) { + Some(SuggestAsRefKind::Option) => Some( + "you can convert from `&Option<T>` to `Option<&T>` using \ + `.as_ref()`", + ), + Some(SuggestAsRefKind::Result) => Some( + "you can convert from `&Result<T, E>` to \ + `Result<&T, &E>` using `.as_ref()`", + ), + None => None, + } + } /// Try to find code with pattern `if Some(..) = expr` /// use a `visitor` to mark the `if` which its span contains given error span, /// and then try to find a assignment in the `cond` part, which span is equal with error span pub(super) fn suggest_let_for_letchains( &self, - err: &mut Diagnostic, cause: &ObligationCause<'_>, span: Span, - ) { + ) -> Option<TypeErrorAdditionalDiags> { let hir = self.tcx.hir(); if let Some(node) = self.tcx.hir().find_by_def_id(cause.body_id) && let hir::Node::Item(hir::Item { @@ -549,9 +531,10 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { let mut visitor = IfVisitor { err_span: span, found_if: false, result: false }; visitor.visit_body(&body); if visitor.result { - err.subdiagnostic(SuggAddLetForLetChains{span: span.shrink_to_lo()}); + return Some(TypeErrorAdditionalDiags::AddLetForLetChains{span: span.shrink_to_lo()}); } } + None } } |