diff options
Diffstat (limited to '')
-rw-r--r-- | compiler/rustc_infer/src/infer/error_reporting/mod.rs | 933 |
1 files changed, 185 insertions, 748 deletions
diff --git a/compiler/rustc_infer/src/infer/error_reporting/mod.rs b/compiler/rustc_infer/src/infer/error_reporting/mod.rs index 9ff703e52..987559d7e 100644 --- a/compiler/rustc_infer/src/infer/error_reporting/mod.rs +++ b/compiler/rustc_infer/src/infer/error_reporting/mod.rs @@ -1,3 +1,4 @@ +// ignore-tidy-filelength //! Error Reporting Code for the inference engine //! //! Because of the way inference, and in particular region inference, @@ -55,10 +56,9 @@ use crate::infer::ExpectedFound; use crate::traits::error_reporting::report_object_safety_error; use crate::traits::{ IfExpressionCause, MatchExpressionArmCause, ObligationCause, ObligationCauseCode, - StatementAsExpression, }; -use rustc_data_structures::fx::{FxHashMap, FxHashSet}; +use rustc_data_structures::fx::{FxIndexMap, FxIndexSet}; use rustc_errors::{pluralize, struct_span_err, Diagnostic, ErrorGuaranteed, IntoDiagnosticArg}; use rustc_errors::{Applicability, DiagnosticBuilder, DiagnosticStyledString, MultiSpan}; use rustc_hir as hir; @@ -67,18 +67,19 @@ use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_hir::lang_items::LangItem; use rustc_hir::Node; use rustc_middle::dep_graph::DepContext; -use rustc_middle::ty::print::with_no_trimmed_paths; use rustc_middle::ty::relate::{self, RelateResult, TypeRelation}; use rustc_middle::ty::{ - self, error::TypeError, Binder, List, Region, Ty, TyCtxt, TypeFoldable, TypeSuperVisitable, + self, error::TypeError, List, Region, Ty, TyCtxt, TypeFoldable, TypeSuperVisitable, TypeVisitable, }; use rustc_span::{sym, symbol::kw, BytePos, DesugaringKind, Pos, Span}; use rustc_target::spec::abi; use std::ops::{ControlFlow, Deref}; +use std::path::PathBuf; use std::{cmp, fmt, iter}; mod note; +mod suggest; pub(crate) mod need_type_info; pub use need_type_info::TypeAnnotationNeeded; @@ -91,6 +92,8 @@ pub mod nice_region_error; pub struct TypeErrCtxt<'a, 'tcx> { pub infcx: &'a InferCtxt<'tcx>, pub typeck_results: Option<std::cell::Ref<'a, ty::TypeckResults<'tcx>>>, + pub normalize_fn_sig: Box<dyn Fn(ty::PolyFnSig<'tcx>) -> ty::PolyFnSig<'tcx> + 'a>, + pub fallback_has_occurred: bool, } impl TypeErrCtxt<'_, '_> { @@ -206,9 +209,12 @@ fn msg_span_from_early_bound_and_free_regions<'tcx>( }; (text, sp) } - ty::BrAnon(idx) => ( + ty::BrAnon(idx, span) => ( format!("the anonymous lifetime #{} defined here", idx + 1), - tcx.def_span(scope) + match span { + Some(span) => span, + None => tcx.def_span(scope) + } ), _ => ( format!("the lifetime `{}` as defined here", region), @@ -253,6 +259,7 @@ fn label_msg_span( } } +#[instrument(level = "trace", skip(tcx))] pub fn unexpected_hidden_region_diagnostic<'tcx>( tcx: TyCtxt<'tcx>, span: Span, @@ -330,33 +337,36 @@ pub fn unexpected_hidden_region_diagnostic<'tcx>( } impl<'tcx> InferCtxt<'tcx> { - pub fn get_impl_future_output_ty(&self, ty: Ty<'tcx>) -> Option<Binder<'tcx, Ty<'tcx>>> { - if let ty::Opaque(def_id, substs) = ty.kind() { - let future_trait = self.tcx.require_lang_item(LangItem::Future, None); - // Future::Output - let item_def_id = self.tcx.associated_item_def_ids(future_trait)[0]; + pub fn get_impl_future_output_ty(&self, ty: Ty<'tcx>) -> Option<Ty<'tcx>> { + let (def_id, substs) = match *ty.kind() { + ty::Opaque(def_id, substs) => (def_id, substs), + ty::Projection(data) + if self.tcx.def_kind(data.item_def_id) == DefKind::ImplTraitPlaceholder => + { + (data.item_def_id, data.substs) + } + _ => return None, + }; - let bounds = self.tcx.bound_explicit_item_bounds(*def_id); + let future_trait = self.tcx.require_lang_item(LangItem::Future, None); + let item_def_id = self.tcx.associated_item_def_ids(future_trait)[0]; - for (predicate, _) in bounds.subst_iter_copied(self.tcx, substs) { - let output = predicate + self.tcx.bound_explicit_item_bounds(def_id).subst_iter_copied(self.tcx, substs).find_map( + |(predicate, _)| { + predicate .kind() .map_bound(|kind| match kind { - ty::PredicateKind::Projection(projection_predicate) + ty::PredicateKind::Clause(ty::Clause::Projection(projection_predicate)) if projection_predicate.projection_ty.item_def_id == item_def_id => { projection_predicate.term.ty() } _ => None, }) - .transpose(); - if output.is_some() { - // We don't account for multiple `Future::Output = Ty` constraints. - return output; - } - } - } - None + .no_bound_vars() + .flatten() + }, + ) } } @@ -534,7 +544,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { fn print_dyn_existential( self, - _predicates: &'tcx ty::List<ty::Binder<'tcx, ty::ExistentialPredicate<'tcx>>>, + _predicates: &'tcx ty::List<ty::PolyExistentialPredicate<'tcx>>, ) -> Result<Self::DynExistential, Self::Error> { Err(NonTrivialPath) } @@ -793,87 +803,6 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { } } - fn suggest_remove_semi_or_return_binding( - &self, - err: &mut Diagnostic, - first_id: Option<hir::HirId>, - first_ty: Ty<'tcx>, - first_span: Span, - second_id: Option<hir::HirId>, - second_ty: Ty<'tcx>, - second_span: Span, - ) { - let remove_semicolon = [ - (first_id, self.resolve_vars_if_possible(second_ty)), - (second_id, self.resolve_vars_if_possible(first_ty)), - ] - .into_iter() - .find_map(|(id, ty)| { - let hir::Node::Block(blk) = self.tcx.hir().get(id?) else { return None }; - self.could_remove_semicolon(blk, ty) - }); - match remove_semicolon { - Some((sp, StatementAsExpression::NeedsBoxing)) => { - err.multipart_suggestion( - "consider removing this semicolon and boxing the expressions", - vec![ - (first_span.shrink_to_lo(), "Box::new(".to_string()), - (first_span.shrink_to_hi(), ")".to_string()), - (second_span.shrink_to_lo(), "Box::new(".to_string()), - (second_span.shrink_to_hi(), ")".to_string()), - (sp, String::new()), - ], - Applicability::MachineApplicable, - ); - } - Some((sp, StatementAsExpression::CorrectType)) => { - err.span_suggestion_short( - sp, - "consider removing this semicolon", - "", - Applicability::MachineApplicable, - ); - } - None => { - for (id, ty) in [(first_id, second_ty), (second_id, first_ty)] { - if let Some(id) = id - && let hir::Node::Block(blk) = self.tcx.hir().get(id) - && self.consider_returning_binding(blk, ty, err) - { - break; - } - } - } - } - } - - fn suggest_boxing_for_return_impl_trait( - &self, - err: &mut Diagnostic, - 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, - ); - } - /// Given that `other_ty` is the same as a type argument for `name` in `sub`, populate `value` /// highlighting `name` and every type argument that isn't at `pos` (which is `other_ty`), and /// populate `other_value` with `other_ty`. @@ -1003,22 +932,14 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { } } - fn normalize_fn_sig_for_diagnostic(&self, sig: ty::PolyFnSig<'tcx>) -> ty::PolyFnSig<'tcx> { - if let Some(normalize) = &self.normalize_fn_sig_for_diagnostic { - normalize(self, sig) - } else { - sig - } - } - /// Given two `fn` signatures highlight only sub-parts that are different. fn cmp_fn_sig( &self, sig1: &ty::PolyFnSig<'tcx>, sig2: &ty::PolyFnSig<'tcx>, ) -> (DiagnosticStyledString, DiagnosticStyledString) { - let sig1 = &self.normalize_fn_sig_for_diagnostic(*sig1); - let sig2 = &self.normalize_fn_sig_for_diagnostic(*sig2); + let sig1 = &(self.normalize_fn_sig)(*sig1); + let sig2 = &(self.normalize_fn_sig)(*sig2); let get_lifetimes = |sig| { use rustc_hir::def::Namespace; @@ -1258,7 +1179,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { let num_display_types = consts_offset - regions_len; for (i, (ta1, ta2)) in type_arguments.take(num_display_types).enumerate() { let i = i + regions_len; - if ta1 == ta2 { + if ta1 == ta2 && !self.tcx.sess.verbose() { values.0.push_normal("_"); values.1.push_normal("_"); } else { @@ -1274,7 +1195,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { let const_arguments = sub1.consts().zip(sub2.consts()); for (i, (ca1, ca2)) in const_arguments.enumerate() { let i = i + consts_offset; - if ca1 == ca2 { + if ca1 == ca2 && !self.tcx.sess.verbose() { values.0.push_normal("_"); values.1.push_normal("_"); } else { @@ -1347,10 +1268,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { .map(|(mod_str, _)| mod_str.len() + separator_len) .sum(); - debug!( - "cmp: separator_len={}, split_idx={}, min_len={}", - separator_len, split_idx, min_len - ); + debug!(?separator_len, ?split_idx, ?min_len, "cmp"); if split_idx >= min_len { // paths are identical, highlight everything @@ -1361,7 +1279,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { } else { let (common, uniq1) = t1_str.split_at(split_idx); let (_, uniq2) = t2_str.split_at(split_idx); - debug!("cmp: common={}, uniq1={}, uniq2={}", common, uniq1, uniq2); + debug!(?common, ?uniq1, ?uniq2, "cmp"); values.0.push_normal(common); values.0.push_highlighted(uniq1); @@ -1453,7 +1371,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { (ty::FnPtr(sig1), ty::FnPtr(sig2)) => self.cmp_fn_sig(sig1, sig2), _ => { - if t1 == t2 { + if t1 == t2 && !self.tcx.sess.verbose() { // The two types are the same, elide and don't highlight. (DiagnosticStyledString::normal("_"), DiagnosticStyledString::normal("_")) } else { @@ -1498,9 +1416,9 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { values = None; } struct OpaqueTypesVisitor<'tcx> { - types: FxHashMap<TyCategory, FxHashSet<Span>>, - expected: FxHashMap<TyCategory, FxHashSet<Span>>, - found: FxHashMap<TyCategory, FxHashSet<Span>>, + types: FxIndexMap<TyCategory, FxIndexSet<Span>>, + expected: FxIndexMap<TyCategory, FxIndexSet<Span>>, + found: FxIndexMap<TyCategory, FxIndexSet<Span>>, ignore_span: Span, tcx: TyCtxt<'tcx>, } @@ -1538,7 +1456,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { &self, err: &mut Diagnostic, target: &str, - types: &FxHashMap<TyCategory, FxHashSet<Span>>, + types: &FxIndexMap<TyCategory, FxIndexSet<Span>>, ) { for (key, values) in types.iter() { let count = values.len(); @@ -1654,55 +1572,46 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { } ValuePairs::Regions(_) => (false, Mismatch::Fixed("lifetime")), }; - let vals = match self.values_str(values) { - Some((expected, found)) => Some((expected, found)), - None => { - // Derived error. Cancel the emitter. - // NOTE(eddyb) this was `.cancel()`, but `diag` - // is borrowed, so we can't fully defuse it. - diag.downgrade_to_delayed_bug(); - return; - } + let Some(vals) = self.values_str(values) else { + // Derived error. Cancel the emitter. + // NOTE(eddyb) this was `.cancel()`, but `diag` + // is borrowed, so we can't fully defuse it. + diag.downgrade_to_delayed_bug(); + return; }; - (vals, exp_found, is_simple_error, Some(values)) + (Some(vals), exp_found, is_simple_error, Some(values)) } }; - match terr { - // Ignore msg for object safe coercion - // since E0038 message will be printed - TypeError::ObjectUnsafeCoercion(_) => {} - _ => { - let mut label_or_note = |span: Span, msg: &str| { - if (prefer_label && is_simple_error) || &[span] == diag.span.primary_spans() { - diag.span_label(span, msg); - } else { - diag.span_note(span, msg); - } - }; - if let Some((sp, msg)) = secondary_span { - if swap_secondary_and_primary { - let terr = if let Some(infer::ValuePairs::Terms(infer::ExpectedFound { - expected, - .. - })) = values - { - format!("expected this to be `{}`", expected) - } else { - terr.to_string() - }; - label_or_note(sp, &terr); - label_or_note(span, &msg); - } else { - label_or_note(span, &terr.to_string()); - label_or_note(sp, &msg); - } - } else { - label_or_note(span, &terr.to_string()); - } + let mut label_or_note = |span: Span, msg: &str| { + if (prefer_label && is_simple_error) || &[span] == diag.span.primary_spans() { + diag.span_label(span, msg); + } else { + diag.span_note(span, msg); } }; - if let Some((expected, found)) = expected_found { + if let Some((sp, msg)) = secondary_span { + if swap_secondary_and_primary { + let terr = if let Some(infer::ValuePairs::Terms(infer::ExpectedFound { + expected, + .. + })) = values + { + format!("expected this to be `{}`", expected) + } else { + terr.to_string() + }; + label_or_note(sp, &terr); + label_or_note(span, &msg); + } else { + label_or_note(span, &terr.to_string()); + label_or_note(sp, &msg); + } + } else { + label_or_note(span, &terr.to_string()); + } + + if let Some((expected, found, exp_p, found_p)) = expected_found { let (expected_label, found_label, exp_found) = match exp_found { Mismatch::Variable(ef) => ( ef.expected.prefix_string(self.tcx), @@ -1819,32 +1728,41 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { } TypeError::Sorts(values) => { let extra = expected == found; - let sort_string = |ty: Ty<'tcx>| match (extra, ty.kind()) { - (true, ty::Opaque(def_id, _)) => { - let sm = self.tcx.sess.source_map(); - let pos = sm.lookup_char_pos(self.tcx.def_span(*def_id).lo()); - format!( - " (opaque type at <{}:{}:{}>)", - sm.filename_for_diagnostics(&pos.file.name), - pos.line, - pos.col.to_usize() + 1, - ) - } - (true, ty::Projection(proj)) - if self.tcx.def_kind(proj.item_def_id) - == DefKind::ImplTraitPlaceholder => - { - let sm = self.tcx.sess.source_map(); - let pos = sm.lookup_char_pos(self.tcx.def_span(proj.item_def_id).lo()); - format!( - " (trait associated opaque type at <{}:{}:{}>)", - sm.filename_for_diagnostics(&pos.file.name), - pos.line, - pos.col.to_usize() + 1, - ) + let sort_string = |ty: Ty<'tcx>, path: Option<PathBuf>| { + let mut s = match (extra, ty.kind()) { + (true, ty::Opaque(def_id, _)) => { + let sm = self.tcx.sess.source_map(); + let pos = sm.lookup_char_pos(self.tcx.def_span(*def_id).lo()); + format!( + " (opaque type at <{}:{}:{}>)", + sm.filename_for_diagnostics(&pos.file.name), + pos.line, + pos.col.to_usize() + 1, + ) + } + (true, ty::Projection(proj)) + if self.tcx.def_kind(proj.item_def_id) + == DefKind::ImplTraitPlaceholder => + { + let sm = self.tcx.sess.source_map(); + let pos = sm.lookup_char_pos(self.tcx.def_span(proj.item_def_id).lo()); + format!( + " (trait associated opaque type at <{}:{}:{}>)", + sm.filename_for_diagnostics(&pos.file.name), + pos.line, + pos.col.to_usize() + 1, + ) + } + (true, _) => format!(" ({})", ty.sort_string(self.tcx)), + (false, _) => "".to_string(), + }; + if let Some(path) = path { + s.push_str(&format!( + "\nthe full type name has been written to '{}'", + path.display(), + )); } - (true, _) => format!(" ({})", ty.sort_string(self.tcx)), - (false, _) => "".to_string(), + s }; if !(values.expected.is_simple_text() && values.found.is_simple_text()) || (exp_found.map_or(false, |ef| { @@ -1866,14 +1784,11 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { expected, &found_label, found, - &sort_string(values.expected), - &sort_string(values.found), + &sort_string(values.expected, exp_p), + &sort_string(values.found, found_p), ); } } - TypeError::ObjectUnsafeCoercion(_) => { - diag.note_unsuccessful_coercion(found, expected); - } _ => { debug!( "note_type_err: exp_found={:?}, expected={:?} found={:?}", @@ -1944,310 +1859,6 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { debug!(?diag); } - fn suggest_tuple_pattern( - &self, - cause: &ObligationCause<'tcx>, - exp_found: &ty::error::ExpectedFound<Ty<'tcx>>, - diag: &mut Diagnostic, - ) { - // Heavily inspired by `FnCtxt::suggest_compatible_variants`, with - // some modifications due to that being in typeck and this being in infer. - if let ObligationCauseCode::Pattern { .. } = cause.code() { - if let ty::Adt(expected_adt, substs) = exp_found.expected.kind() { - let compatible_variants: Vec<_> = expected_adt - .variants() - .iter() - .filter(|variant| { - variant.fields.len() == 1 && variant.ctor_kind == hir::def::CtorKind::Fn - }) - .filter_map(|variant| { - let sole_field = &variant.fields[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 = - with_no_trimmed_paths!(self.tcx.def_path_str(variant.def_id)); - // FIXME #56861: DRYer prelude filtering - if let Some(path) = variant_path.strip_prefix("std::prelude::") { - if let Some((_, path)) = path.split_once("::") { - return Some(path.to_string()); - } - } - Some(variant_path) - } else { - None - } - }) - .collect(); - 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, - ); - } - _ => { - // 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, - ); - } - } - } - } - } - - /// A possible error is to forget to add `.await` when using futures: - /// - /// ```compile_fail,E0308 - /// async fn make_u32() -> u32 { - /// 22 - /// } - /// - /// fn take_u32(x: u32) {} - /// - /// async fn foo() { - /// let x = make_u32(); - /// take_u32(x); - /// } - /// ``` - /// - /// This routine checks if the found type `T` implements `Future<Output=U>` where `U` is the - /// expected type. If this is the case, and we are inside of an async body, it suggests adding - /// `.await` to the tail of the expression. - fn suggest_await_on_expect_found( - &self, - cause: &ObligationCause<'tcx>, - exp_span: Span, - exp_found: &ty::error::ExpectedFound<Ty<'tcx>>, - diag: &mut Diagnostic, - ) { - debug!( - "suggest_await_on_expect_found: exp_span={:?}, expected_ty={:?}, found_ty={:?}", - exp_span, exp_found.expected, exp_found.found, - ); - - if let ObligationCauseCode::CompareImplItemObligation { .. } = cause.code() { - return; - } - - match ( - self.get_impl_future_output_ty(exp_found.expected).map(Binder::skip_binder), - self.get_impl_future_output_ty(exp_found.found).map(Binder::skip_binder), - ) { - (Some(exp), Some(found)) if self.same_type_modulo_infer(exp, found) => match cause - .code() - { - ObligationCauseCode::IfExpression(box IfExpressionCause { then_id, .. }) => { - let then_span = self.find_block_span_from_hir_id(*then_id); - diag.multipart_suggestion( - "consider `await`ing on both `Future`s", - vec![ - (then_span.shrink_to_hi(), ".await".to_string()), - (exp_span.shrink_to_hi(), ".await".to_string()), - ], - Applicability::MaybeIncorrect, - ); - } - ObligationCauseCode::MatchExpressionArm(box MatchExpressionArmCause { - prior_arms, - .. - }) => { - if let [.., arm_span] = &prior_arms[..] { - diag.multipart_suggestion( - "consider `await`ing on both `Future`s", - vec![ - (arm_span.shrink_to_hi(), ".await".to_string()), - (exp_span.shrink_to_hi(), ".await".to_string()), - ], - Applicability::MaybeIncorrect, - ); - } else { - diag.help("consider `await`ing on both `Future`s"); - } - } - _ => { - diag.help("consider `await`ing on both `Future`s"); - } - }, - (_, Some(ty)) if self.same_type_modulo_infer(exp_found.expected, ty) => { - diag.span_suggestion_verbose( - exp_span.shrink_to_hi(), - "consider `await`ing on the `Future`", - ".await", - Applicability::MaybeIncorrect, - ); - } - (Some(ty), _) if self.same_type_modulo_infer(ty, exp_found.found) => match cause.code() - { - ObligationCauseCode::Pattern { span: Some(then_span), .. } => { - diag.span_suggestion_verbose( - then_span.shrink_to_hi(), - "consider `await`ing on the `Future`", - ".await", - Applicability::MaybeIncorrect, - ); - } - ObligationCauseCode::IfExpression(box IfExpressionCause { then_id, .. }) => { - let then_span = self.find_block_span_from_hir_id(*then_id); - diag.span_suggestion_verbose( - then_span.shrink_to_hi(), - "consider `await`ing on the `Future`", - ".await", - Applicability::MaybeIncorrect, - ); - } - ObligationCauseCode::MatchExpressionArm(box MatchExpressionArmCause { - ref prior_arms, - .. - }) => { - diag.multipart_suggestion_verbose( - "consider `await`ing on the `Future`", - prior_arms - .iter() - .map(|arm| (arm.shrink_to_hi(), ".await".to_string())) - .collect(), - Applicability::MaybeIncorrect, - ); - } - _ => {} - }, - _ => {} - } - } - - fn suggest_accessing_field_where_appropriate( - &self, - cause: &ObligationCause<'tcx>, - exp_found: &ty::error::ExpectedFound<Ty<'tcx>>, - diag: &mut Diagnostic, - ) { - debug!( - "suggest_accessing_field_where_appropriate(cause={:?}, exp_found={:?})", - cause, exp_found - ); - if let ty::Adt(expected_def, expected_substs) = exp_found.expected.kind() { - if expected_def.is_enum() { - return; - } - - if let Some((name, ty)) = expected_def - .non_enum_variant() - .fields - .iter() - .filter(|field| field.vis.is_accessible_from(field.did, self.tcx)) - .map(|field| (field.name, field.ty(self.tcx, expected_substs))) - .find(|(_, ty)| self.same_type_modulo_infer(*ty, exp_found.found)) - { - 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) - } else if expected_def.is_union() { - format!("unsafe {{ {}.{} }}", snippet, name) - } else { - return; - }; - diag.span_suggestion( - span, - &format!( - "you might have meant to use field `{}` whose type is `{}`", - name, ty - ), - suggestion, - Applicability::MaybeIncorrect, - ); - } - } - } - } - } - - /// When encountering a case where `.as_ref()` on a `Result` or `Option` would be appropriate, - /// suggests it. - fn suggest_as_ref_where_appropriate( - &self, - span: Span, - exp_found: &ty::error::ExpectedFound<Ty<'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) - { - 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, - ); - } - } - - pub fn should_suggest_as_ref(&self, expected: Ty<'tcx>, found: Ty<'tcx>) -> Option<&str> { - 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()`", - ), - ]; - if let Some(msg) = have_as_ref.iter().find_map(|(name, msg)| { - self.tcx.is_diagnostic_item(*name, exp_def.did()).then_some(msg) - }) { - let mut show_suggestion = true; - for (exp_ty, found_ty) in - iter::zip(exp_substs.types(), found_substs.types()) - { - match *exp_ty.kind() { - ty::Ref(_, exp_ty, _) => { - match (exp_ty.kind(), found_ty.kind()) { - (_, ty::Param(_)) - | (_, ty::Infer(_)) - | (ty::Param(_), _) - | (ty::Infer(_), _) => {} - _ if self.same_type_modulo_infer(exp_ty, found_ty) => {} - _ => show_suggestion = false, - }; - } - ty::Param(_) | ty::Infer(_) => {} - _ => show_suggestion = false, - } - } - if show_suggestion { - return Some(*msg); - } - } - } - } - } - None - } - pub fn report_and_explain_type_error( &self, trace: TypeTrace<'tcx>, @@ -2332,13 +1943,18 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { } } } + // For code `if Some(..) = expr `, the type mismatch may be expected `bool` but found `()`, + // we try to suggest to add the missing `let` for `if let Some(..) = expr` + (ty::Bool, ty::Tuple(list)) => if list.len() == 0 { + self.suggest_let_for_letchains(&mut err, &trace.cause, span); + } _ => {} } } let code = trace.cause.code(); if let &MatchExpressionArm(box MatchExpressionArmCause { source, .. }) = code && let hir::MatchSource::TryDesugar = source - && let Some((expected_ty, found_ty)) = self.values_str(trace.values) + && let Some((expected_ty, found_ty, _, _)) = self.values_str(trace.values) { err.note(&format!( "`?` operator cannot convert from `{}` to `{}`", @@ -2393,7 +2009,8 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { fn values_str( &self, values: ValuePairs<'tcx>, - ) -> Option<(DiagnosticStyledString, DiagnosticStyledString)> { + ) -> Option<(DiagnosticStyledString, DiagnosticStyledString, Option<PathBuf>, Option<PathBuf>)> + { match values { infer::Regions(exp_found) => self.expected_found_str(exp_found), infer::Terms(exp_found) => self.expected_found_str_term(exp_found), @@ -2403,7 +2020,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { found: exp_found.found.print_only_trait_path(), }; match self.expected_found_str(pretty_exp_found) { - Some((expected, found)) if expected == found => { + Some((expected, found, _, _)) if expected == found => { self.expected_found_str(exp_found) } ret => ret, @@ -2415,7 +2032,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { found: exp_found.found.print_only_trait_path(), }; match self.expected_found_str(pretty_exp_found) { - Some((expected, found)) if expected == found => { + Some((expected, found, _, _)) if expected == found => { self.expected_found_str(exp_found) } ret => ret, @@ -2427,17 +2044,41 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { fn expected_found_str_term( &self, exp_found: ty::error::ExpectedFound<ty::Term<'tcx>>, - ) -> Option<(DiagnosticStyledString, DiagnosticStyledString)> { + ) -> Option<(DiagnosticStyledString, DiagnosticStyledString, Option<PathBuf>, Option<PathBuf>)> + { let exp_found = self.resolve_vars_if_possible(exp_found); if exp_found.references_error() { return None; } Some(match (exp_found.expected.unpack(), exp_found.found.unpack()) { - (ty::TermKind::Ty(expected), ty::TermKind::Ty(found)) => self.cmp(expected, found), + (ty::TermKind::Ty(expected), ty::TermKind::Ty(found)) => { + let (mut exp, mut fnd) = self.cmp(expected, found); + // Use the terminal width as the basis to determine when to compress the printed + // out type, but give ourselves some leeway to avoid ending up creating a file for + // a type that is somewhat shorter than the path we'd write to. + let len = self.tcx.sess().diagnostic_width() + 40; + let exp_s = exp.content(); + let fnd_s = fnd.content(); + let mut exp_p = None; + let mut fnd_p = None; + if exp_s.len() > len { + let (exp_s, exp_path) = self.tcx.short_ty_string(expected); + exp = DiagnosticStyledString::highlighted(exp_s); + exp_p = exp_path; + } + if fnd_s.len() > len { + let (fnd_s, fnd_path) = self.tcx.short_ty_string(found); + fnd = DiagnosticStyledString::highlighted(fnd_s); + fnd_p = fnd_path; + } + (exp, fnd, exp_p, fnd_p) + } _ => ( DiagnosticStyledString::highlighted(exp_found.expected.to_string()), DiagnosticStyledString::highlighted(exp_found.found.to_string()), + None, + None, ), }) } @@ -2446,7 +2087,8 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { fn expected_found_str<T: fmt::Display + TypeFoldable<'tcx>>( &self, exp_found: ty::error::ExpectedFound<T>, - ) -> Option<(DiagnosticStyledString, DiagnosticStyledString)> { + ) -> Option<(DiagnosticStyledString, DiagnosticStyledString, Option<PathBuf>, Option<PathBuf>)> + { let exp_found = self.resolve_vars_if_possible(exp_found); if exp_found.references_error() { return None; @@ -2455,6 +2097,8 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { Some(( DiagnosticStyledString::highlighted(exp_found.expected.to_string()), DiagnosticStyledString::highlighted(exp_found.found.to_string()), + None, + None, )) } @@ -2788,36 +2432,29 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { debug!("report_sub_sup_conflict: sup_region={:?}", sup_region); debug!("report_sub_sup_conflict: sup_origin={:?}", sup_origin); - if let (&infer::Subtype(ref sup_trace), &infer::Subtype(ref sub_trace)) = - (&sup_origin, &sub_origin) + if let infer::Subtype(ref sup_trace) = sup_origin + && let infer::Subtype(ref sub_trace) = sub_origin + && let Some((sup_expected, sup_found, _, _)) = self.values_str(sup_trace.values) + && let Some((sub_expected, sub_found, _, _)) = self.values_str(sub_trace.values) + && sub_expected == sup_expected + && sub_found == sup_found { - debug!("report_sub_sup_conflict: sup_trace={:?}", sup_trace); - debug!("report_sub_sup_conflict: sub_trace={:?}", sub_trace); - debug!("report_sub_sup_conflict: sup_trace.values={:?}", sup_trace.values); - debug!("report_sub_sup_conflict: sub_trace.values={:?}", sub_trace.values); - - if let (Some((sup_expected, sup_found)), Some((sub_expected, sub_found))) = - (self.values_str(sup_trace.values), self.values_str(sub_trace.values)) - { - if sub_expected == sup_expected && sub_found == sup_found { - note_and_explain_region( - self.tcx, - &mut err, - "...but the lifetime must also be valid for ", - sub_region, - "...", - None, - ); - err.span_note( - sup_trace.cause.span, - &format!("...so that the {}", sup_trace.cause.as_requirement_str()), - ); + note_and_explain_region( + self.tcx, + &mut err, + "...but the lifetime must also be valid for ", + sub_region, + "...", + None, + ); + err.span_note( + sup_trace.cause.span, + &format!("...so that the {}", sup_trace.cause.as_requirement_str()), + ); - err.note_expected_found(&"", sup_expected, &"", sup_found); - err.emit(); - return; - } - } + err.note_expected_found(&"", sup_expected, &"", sup_found); + err.emit(); + return; } self.note_region_origin(&mut err, &sup_origin); @@ -2862,6 +2499,11 @@ impl<'tcx> TypeRelation<'tcx> for SameTypeModuloInfer<'_, 'tcx> { self.0.tcx } + fn intercrate(&self) -> bool { + assert!(!self.0.intercrate); + false + } + fn param_env(&self) -> ty::ParamEnv<'tcx> { // Unused, only for consts which we treat as always equal ty::ParamEnv::empty() @@ -2875,6 +2517,10 @@ impl<'tcx> TypeRelation<'tcx> for SameTypeModuloInfer<'_, 'tcx> { true } + fn mark_ambiguous(&mut self) { + bug!() + } + fn relate_with_variance<T: relate::Relate<'tcx>>( &mut self, _variance: ty::Variance, @@ -3043,7 +2689,6 @@ impl<'tcx> ObligationCauseExt<'tcx> for ObligationCause<'tcx> { TypeError::IntrinsicCast => { Error0308("cannot coerce intrinsics to function pointers") } - TypeError::ObjectUnsafeCoercion(did) => Error0038(did), _ => Error0308("mismatched types"), }, } @@ -3158,211 +2803,3 @@ impl<'tcx> InferCtxt<'tcx> { } } } - -impl<'tcx> TypeErrCtxt<'_, 'tcx> { - /// Be helpful when the user wrote `{... expr; }` and taking the `;` off - /// is enough to fix the error. - pub fn could_remove_semicolon( - &self, - blk: &'tcx hir::Block<'tcx>, - expected_ty: Ty<'tcx>, - ) -> Option<(Span, StatementAsExpression)> { - let blk = blk.innermost_block(); - // Do not suggest if we have a tail expr. - if blk.expr.is_some() { - return None; - } - let last_stmt = blk.stmts.last()?; - let hir::StmtKind::Semi(ref last_expr) = last_stmt.kind else { - return None; - }; - let last_expr_ty = self.typeck_results.as_ref()?.expr_ty_opt(*last_expr)?; - let needs_box = match (last_expr_ty.kind(), expected_ty.kind()) { - _ if last_expr_ty.references_error() => return None, - _ if self.same_type_modulo_infer(last_expr_ty, expected_ty) => { - StatementAsExpression::CorrectType - } - (ty::Opaque(last_def_id, _), ty::Opaque(exp_def_id, _)) - if last_def_id == exp_def_id => - { - StatementAsExpression::CorrectType - } - (ty::Opaque(last_def_id, last_bounds), ty::Opaque(exp_def_id, exp_bounds)) => { - debug!( - "both opaque, likely future {:?} {:?} {:?} {:?}", - last_def_id, last_bounds, exp_def_id, exp_bounds - ); - - let last_local_id = last_def_id.as_local()?; - let exp_local_id = exp_def_id.as_local()?; - - match ( - &self.tcx.hir().expect_item(last_local_id).kind, - &self.tcx.hir().expect_item(exp_local_id).kind, - ) { - ( - hir::ItemKind::OpaqueTy(hir::OpaqueTy { bounds: last_bounds, .. }), - hir::ItemKind::OpaqueTy(hir::OpaqueTy { bounds: exp_bounds, .. }), - ) if iter::zip(*last_bounds, *exp_bounds).all(|(left, right)| { - match (left, right) { - ( - hir::GenericBound::Trait(tl, ml), - hir::GenericBound::Trait(tr, mr), - ) if tl.trait_ref.trait_def_id() == tr.trait_ref.trait_def_id() - && ml == mr => - { - true - } - ( - hir::GenericBound::LangItemTrait(langl, _, _, argsl), - hir::GenericBound::LangItemTrait(langr, _, _, argsr), - ) if langl == langr => { - // FIXME: consider the bounds! - debug!("{:?} {:?}", argsl, argsr); - true - } - _ => false, - } - }) => - { - StatementAsExpression::NeedsBoxing - } - _ => StatementAsExpression::CorrectType, - } - } - _ => return None, - }; - let span = if last_stmt.span.from_expansion() { - let mac_call = rustc_span::source_map::original_sp(last_stmt.span, blk.span); - self.tcx.sess.source_map().mac_call_stmt_semi_span(mac_call)? - } else { - last_stmt.span.with_lo(last_stmt.span.hi() - BytePos(1)) - }; - Some((span, needs_box)) - } - - /// Suggest returning a local binding with a compatible type if the block - /// has no return expression. - pub fn consider_returning_binding( - &self, - blk: &'tcx hir::Block<'tcx>, - expected_ty: Ty<'tcx>, - err: &mut Diagnostic, - ) -> bool { - let blk = blk.innermost_block(); - // Do not suggest if we have a tail expr. - if blk.expr.is_some() { - return false; - } - let mut shadowed = FxHashSet::default(); - let mut candidate_idents = vec![]; - let mut find_compatible_candidates = |pat: &hir::Pat<'_>| { - if let hir::PatKind::Binding(_, hir_id, ident, _) = &pat.kind - && let Some(pat_ty) = self - .typeck_results - .as_ref() - .and_then(|typeck_results| typeck_results.node_type_opt(*hir_id)) - { - let pat_ty = self.resolve_vars_if_possible(pat_ty); - if self.same_type_modulo_infer(pat_ty, expected_ty) - && !(pat_ty, expected_ty).references_error() - && shadowed.insert(ident.name) - { - candidate_idents.push((*ident, pat_ty)); - } - } - true - }; - - let hir = self.tcx.hir(); - for stmt in blk.stmts.iter().rev() { - let hir::StmtKind::Local(local) = &stmt.kind else { continue; }; - local.pat.walk(&mut find_compatible_candidates); - } - match hir.find(hir.get_parent_node(blk.hir_id)) { - Some(hir::Node::Expr(hir::Expr { hir_id, .. })) => { - match hir.find(hir.get_parent_node(*hir_id)) { - Some(hir::Node::Arm(hir::Arm { pat, .. })) => { - pat.walk(&mut find_compatible_candidates); - } - Some( - hir::Node::Item(hir::Item { kind: hir::ItemKind::Fn(_, _, body), .. }) - | hir::Node::ImplItem(hir::ImplItem { - kind: hir::ImplItemKind::Fn(_, body), - .. - }) - | hir::Node::TraitItem(hir::TraitItem { - kind: hir::TraitItemKind::Fn(_, hir::TraitFn::Provided(body)), - .. - }) - | hir::Node::Expr(hir::Expr { - kind: hir::ExprKind::Closure(hir::Closure { body, .. }), - .. - }), - ) => { - for param in hir.body(*body).params { - param.pat.walk(&mut find_compatible_candidates); - } - } - Some(hir::Node::Expr(hir::Expr { - kind: - hir::ExprKind::If( - hir::Expr { kind: hir::ExprKind::Let(let_), .. }, - then_block, - _, - ), - .. - })) if then_block.hir_id == *hir_id => { - let_.pat.walk(&mut find_compatible_candidates); - } - _ => {} - } - } - _ => {} - } - - match &candidate_idents[..] { - [(ident, _ty)] => { - let sm = self.tcx.sess.source_map(); - if let Some(stmt) = blk.stmts.last() { - let stmt_span = sm.stmt_span(stmt.span, blk.span); - let sugg = if sm.is_multiline(blk.span) - && let Some(spacing) = sm.indentation_before(stmt_span) - { - format!("\n{spacing}{ident}") - } else { - format!(" {ident}") - }; - err.span_suggestion_verbose( - stmt_span.shrink_to_hi(), - format!("consider returning the local binding `{ident}`"), - sugg, - Applicability::MaybeIncorrect, - ); - } else { - let sugg = if sm.is_multiline(blk.span) - && let Some(spacing) = sm.indentation_before(blk.span.shrink_to_lo()) - { - format!("\n{spacing} {ident}\n{spacing}") - } else { - format!(" {ident} ") - }; - let left_span = sm.span_through_char(blk.span, '{').shrink_to_hi(); - err.span_suggestion_verbose( - sm.span_extend_while(left_span, |c| c.is_whitespace()).unwrap_or(left_span), - format!("consider returning the local binding `{ident}`"), - sugg, - Applicability::MaybeIncorrect, - ); - } - true - } - values if (1..3).contains(&values.len()) => { - let spans = values.iter().map(|(ident, _)| ident.span).collect::<Vec<_>>(); - err.span_note(spans, "consider returning one of these bindings"); - true - } - _ => false, - } - } -} |