From 20431706a863f92cb37dc512fef6e48d192aaf2c Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 14:11:38 +0200 Subject: Merging upstream version 1.66.0+dfsg1. Signed-off-by: Daniel Baumann --- compiler/rustc_parse/src/parser/generics.rs | 36 +++++++++++++++++++++++++++-- 1 file changed, 34 insertions(+), 2 deletions(-) (limited to 'compiler/rustc_parse/src/parser/generics.rs') diff --git a/compiler/rustc_parse/src/parser/generics.rs b/compiler/rustc_parse/src/parser/generics.rs index 4d0a8b05e..fa75670b2 100644 --- a/compiler/rustc_parse/src/parser/generics.rs +++ b/compiler/rustc_parse/src/parser/generics.rs @@ -1,7 +1,9 @@ use super::{ForceCollect, Parser, TrailingToken}; use rustc_ast::token; -use rustc_ast::{self as ast, AttrVec, GenericBounds, GenericParam, GenericParamKind, WhereClause}; +use rustc_ast::{ + self as ast, AttrVec, GenericBounds, GenericParam, GenericParamKind, TyKind, WhereClause, +}; use rustc_errors::{Applicability, PResult}; use rustc_span::symbol::kw; @@ -31,13 +33,43 @@ impl<'a> Parser<'a> { let mut colon_span = None; let bounds = if self.eat(&token::Colon) { colon_span = Some(self.prev_token.span); + // recover from `impl Trait` in type param bound + if self.token.is_keyword(kw::Impl) { + let impl_span = self.token.span; + let snapshot = self.create_snapshot_for_diagnostic(); + match self.parse_ty() { + Ok(p) => { + if let TyKind::ImplTrait(_, bounds) = &(*p).kind { + let span = impl_span.to(self.token.span.shrink_to_lo()); + let mut err = self.struct_span_err( + span, + "expected trait bound, found `impl Trait` type", + ); + err.span_label(span, "not a trait"); + if let [bound, ..] = &bounds[..] { + err.span_suggestion_verbose( + impl_span.until(bound.span()), + "use the trait bounds directly", + String::new(), + Applicability::MachineApplicable, + ); + } + err.emit(); + return Err(err); + } + } + Err(err) => { + err.cancel(); + } + } + self.restore_snapshot(snapshot); + } self.parse_generic_bounds(colon_span)? } else { Vec::new() }; let default = if self.eat(&token::Eq) { Some(self.parse_ty()?) } else { None }; - Ok(GenericParam { ident, id: ast::DUMMY_NODE_ID, -- cgit v1.2.3