diff options
Diffstat (limited to 'compiler/rustc_parse/src/parser/expr.rs')
| -rw-r--r-- | compiler/rustc_parse/src/parser/expr.rs | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/compiler/rustc_parse/src/parser/expr.rs b/compiler/rustc_parse/src/parser/expr.rs index 7cb8c35b868..399596692d5 100644 --- a/compiler/rustc_parse/src/parser/expr.rs +++ b/compiler/rustc_parse/src/parser/expr.rs @@ -372,10 +372,17 @@ impl<'a> Parser<'a> { self.sess.ambiguous_block_expr_parse.borrow_mut().insert(sp, lhs.span); false } - (true, Some(AssocOp::LAnd)) => { + (true, Some(AssocOp::LAnd)) | + (true, Some(AssocOp::LOr)) | + (true, Some(AssocOp::BitOr)) => { // `{ 42 } &&x` (#61475) or `{ 42 } && if x { 1 } else { 0 }`. Separated from the // above due to #74233. // These cases are ambiguous and can't be identified in the parser alone. + // + // Bitwise AND is left out because guessing intent is hard. We can make + // suggestions based on the assumption that double-refs are rarely intentional, + // and closures are distinct enough that they don't get mixed up with their + // return value. let sp = self.sess.source_map().start_point(self.token.span); self.sess.ambiguous_block_expr_parse.borrow_mut().insert(sp, lhs.span); false @@ -1244,7 +1251,14 @@ impl<'a> Parser<'a> { } else if self.check(&token::OpenDelim(token::Brace)) { self.parse_block_expr(None, lo, BlockCheckMode::Default, attrs) } else if self.check(&token::BinOp(token::Or)) || self.check(&token::OrOr) { - self.parse_closure_expr(attrs) + self.parse_closure_expr(attrs).map_err(|mut err| { + // If the input is something like `if a { 1 } else { 2 } | if a { 3 } else { 4 }` + // then suggest parens around the lhs. + if let Some(sp) = self.sess.ambiguous_block_expr_parse.borrow().get(&lo) { + self.sess.expr_parentheses_needed(&mut err, *sp); + } + err + }) } else if self.check(&token::OpenDelim(token::Bracket)) { self.parse_array_or_repeat_expr(attrs, token::Bracket) } else if self.check_path() { |