diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/rustc_infer/src/infer/error_reporting/need_type_info.rs | 80 |
1 files changed, 52 insertions, 28 deletions
diff --git a/compiler/rustc_infer/src/infer/error_reporting/need_type_info.rs b/compiler/rustc_infer/src/infer/error_reporting/need_type_info.rs index b0b7fc6ad5a..1c06c45a923 100644 --- a/compiler/rustc_infer/src/infer/error_reporting/need_type_info.rs +++ b/compiler/rustc_infer/src/infer/error_reporting/need_type_info.rs @@ -12,7 +12,7 @@ use rustc_middle::ty::adjustment::{Adjust, Adjustment, AutoBorrow, AutoBorrowMut use rustc_middle::ty::print::{FmtPrinter, PrettyPrinter, Print, Printer}; use rustc_middle::ty::subst::{GenericArg, GenericArgKind, Subst, SubstsRef}; use rustc_middle::ty::{self, DefIdTree, GenericParamDefKind, InferConst}; -use rustc_middle::ty::{Ty, TyCtxt}; +use rustc_middle::ty::{Ty, TyCtxt, TypeckResults}; use rustc_span::symbol::{kw, Ident}; use rustc_span::{BytePos, Span}; use std::borrow::Cow; @@ -272,7 +272,12 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> { parent: None, } } else { - // FIXME: This code seems a bit wrong, idk. + // If we end up here the `FindInferSourceVisitor` + // won't work, as its expected argument isn't an inference variable. + // + // FIXME: Ideally we should look into the generic constant + // to figure out which inference var is actually unresolved so that + // this path is unreachable. let mut printer = ty::print::FmtPrinter::new(self.tcx, Namespace::ValueNS); if let Some(highlight) = highlight { printer.region_highlight_mode = highlight; @@ -289,6 +294,24 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> { } } + /// Used as a fallback in [InferCtxt::emit_inference_failure_err] + /// in case we weren't able to get a better error. + fn bad_inference_failure_err( + &self, + span: Span, + arg_data: InferenceDiagnosticsData, + error_code: TypeAnnotationNeeded, + ) -> DiagnosticBuilder<'tcx, ErrorGuaranteed> { + let error_code = error_code.into(); + let mut err = self.tcx.sess.struct_span_err_with_code( + span, + &format!("type annotations needed"), + error_code, + ); + err.span_label(span, arg_data.cannot_infer_msg()); + err + } + pub fn emit_inference_failure_err( &self, body_id: Option<hir::BodyId>, @@ -301,7 +324,16 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> { let arg = self.resolve_vars_if_possible(arg); let arg_data = self.extract_inference_diagnostics_data(arg, None); - let mut local_visitor = FindInferSourceVisitor::new(&self, arg); + let Some(typeck_results) = self.in_progress_typeck_results else { + // If we don't have any typeck results we're outside + // of a body, so we won't be able to get better info + // here. + return self.bad_inference_failure_err(span, arg_data, error_code); + }; + let typeck_results = typeck_results.borrow(); + let typeck_results = &typeck_results; + + let mut local_visitor = FindInferSourceVisitor::new(&self, typeck_results, arg); if let Some(body_id) = body_id { let expr = self.tcx.hir().expect_expr(body_id.hir_id); debug!(?expr); @@ -309,17 +341,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> { } let Some(InferSource { span, kind }) = local_visitor.infer_source else { - let error_code = error_code.into(); - let mut err = self.tcx.sess.struct_span_err_with_code( - span, - &format!("type annotations needed"), - error_code, - ); - err.span_label( - span, - arg_data.cannot_infer_msg(), - ); - return err; + return self.bad_inference_failure_err(span, arg_data, error_code) }; let error_code = error_code.into(); @@ -394,8 +416,6 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> { ); } InferSourceKind::FullyQualifiedMethodCall { receiver, successor, substs, def_id } => { - let typeck_results = self.in_progress_typeck_results.unwrap(); - let typeck_results = typeck_results.borrow(); let printer = fmt_printer(self, Namespace::ValueNS); let def_path = printer.print_def_path(def_id, substs).unwrap().into_buffer(); @@ -548,6 +568,8 @@ struct InsertableGenericArgs<'tcx> { /// For details on how we rank spots, see [Self::source_cost] struct FindInferSourceVisitor<'a, 'tcx> { infcx: &'a InferCtxt<'a, 'tcx>, + typeck_results: &'a TypeckResults<'tcx>, + target: GenericArg<'tcx>, attempt: usize, @@ -556,9 +578,15 @@ struct FindInferSourceVisitor<'a, 'tcx> { } impl<'a, 'tcx> FindInferSourceVisitor<'a, 'tcx> { - fn new(infcx: &'a InferCtxt<'a, 'tcx>, target: GenericArg<'tcx>) -> Self { + fn new( + infcx: &'a InferCtxt<'a, 'tcx>, + typeck_results: &'a TypeckResults<'tcx>, + target: GenericArg<'tcx>, + ) -> Self { FindInferSourceVisitor { infcx, + typeck_results, + target, attempt: 0, @@ -603,7 +631,6 @@ impl<'a, 'tcx> FindInferSourceVisitor<'a, 'tcx> { variant_cost + generic_args.iter().map(|&arg| arg_cost(arg)).sum::<usize>() } InferSourceKind::FullyQualifiedMethodCall { substs, .. } => { - // FIXME: We should also consider the cost of lifetimes and constants here. 20 + substs.iter().map(|arg| arg_cost(arg)).sum::<usize>() } InferSourceKind::ClosureReturn { ty, should_wrap_expr, .. } => { @@ -625,7 +652,7 @@ impl<'a, 'tcx> FindInferSourceVisitor<'a, 'tcx> { } fn opt_node_type(&self, hir_id: HirId) -> Option<Ty<'tcx>> { - let ty = self.infcx.in_progress_typeck_results?.borrow().node_type_opt(hir_id); + let ty = self.typeck_results.node_type_opt(hir_id); self.infcx.resolve_vars_if_possible(ty) } @@ -698,10 +725,9 @@ impl<'a, 'tcx> FindInferSourceVisitor<'a, 'tcx> { expr: &'tcx hir::Expr<'tcx>, ) -> Box<dyn Iterator<Item = InsertableGenericArgs<'tcx>> + 'a> { let tcx = self.infcx.tcx; - let typeck_results = self.infcx.in_progress_typeck_results.unwrap().borrow(); match expr.kind { hir::ExprKind::Path(ref path) => { - if let Some(substs) = typeck_results.node_substs_opt(expr.hir_id) { + if let Some(substs) = self.typeck_results.node_substs_opt(expr.hir_id) { return self.path_inferred_subst_iter(expr.hir_id, substs, path); } } @@ -713,13 +739,13 @@ impl<'a, 'tcx> FindInferSourceVisitor<'a, 'tcx> { } } hir::ExprKind::MethodCall(segment, _, _) => { - if let Some(def_id) = typeck_results.type_dependent_def_id(expr.hir_id) { + if let Some(def_id) = self.typeck_results.type_dependent_def_id(expr.hir_id) { let generics = tcx.generics_of(def_id); let insertable: Option<_> = try { if generics.has_impl_trait() { None? } - let substs = typeck_results.node_substs_opt(expr.hir_id)?; + let substs = self.typeck_results.node_substs_opt(expr.hir_id)?; let span = tcx.hir().span(segment.hir_id?); let insert_span = segment.ident.span.shrink_to_hi().with_hi(span.hi()); InsertableGenericArgs { @@ -793,13 +819,12 @@ impl<'a, 'tcx> FindInferSourceVisitor<'a, 'tcx> { qpath: &'tcx hir::QPath<'tcx>, ) -> Box<dyn Iterator<Item = InsertableGenericArgs<'tcx>> + 'a> { let tcx = self.infcx.tcx; - let typeck_results = self.infcx.in_progress_typeck_results.unwrap().borrow(); match qpath { hir::QPath::Resolved(_self_ty, path) => { Box::new(self.resolved_path_inferred_subst_iter(path, substs)) } hir::QPath::TypeRelative(ty, segment) => { - let Some(def_id) = typeck_results.type_dependent_def_id(hir_id) else { + let Some(def_id) = self.typeck_results.type_dependent_def_id(hir_id) else { return Box::new(iter::empty()); }; @@ -996,10 +1021,9 @@ impl<'a, 'tcx> Visitor<'tcx> for FindInferSourceVisitor<'a, 'tcx> { .any(|generics| generics.has_impl_trait()) }; if let ExprKind::MethodCall(path, args, span) = expr.kind - && let Some(typeck_results) = self.infcx.in_progress_typeck_results - && let Some(substs) = typeck_results.borrow().node_substs_opt(expr.hir_id) + && let Some(substs) = self.typeck_results.node_substs_opt(expr.hir_id) && substs.iter().any(|arg| self.generic_arg_contains_target(arg)) - && let Some(def_id) = typeck_results.borrow().type_dependent_def_id(expr.hir_id) + && let Some(def_id) = self.typeck_results.type_dependent_def_id(expr.hir_id) && self.infcx.tcx.trait_of_item(def_id).is_some() && !has_impl_trait(def_id) { |