diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/rustc_parse/src/parser/mod.rs | 37 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/tests.rs | 47 |
2 files changed, 28 insertions, 56 deletions
diff --git a/compiler/rustc_parse/src/parser/mod.rs b/compiler/rustc_parse/src/parser/mod.rs index 45ca267fe5d..f906a2ecab7 100644 --- a/compiler/rustc_parse/src/parser/mod.rs +++ b/compiler/rustc_parse/src/parser/mod.rs @@ -1118,41 +1118,8 @@ impl<'a> Parser<'a> { return looker(&self.token); } - if let Some(&(_, span, _, delim)) = self.token_cursor.stack.last() - && delim != Delimiter::Invisible - { - // We are not in the outermost token stream, and the token stream - // we are in has non-skipped delimiters. Look for skipped - // delimiters in the lookahead range. - let tree_cursor = &self.token_cursor.tree_cursor; - let all_normal = (0..dist).all(|i| { - let token = tree_cursor.look_ahead(i); - !matches!(token, Some(TokenTree::Delimited(.., Delimiter::Invisible, _))) - }); - if all_normal { - // There were no skipped delimiters. Do lookahead by plain indexing. - return match tree_cursor.look_ahead(dist - 1) { - Some(tree) => { - // Indexing stayed within the current token stream. - match tree { - TokenTree::Token(token, _) => looker(token), - TokenTree::Delimited(dspan, _, delim, _) => { - looker(&Token::new(token::OpenDelim(*delim), dspan.open)) - } - } - } - None => { - // Indexing went past the end of the current token - // stream. Use the close delimiter, no matter how far - // ahead `dist` went. - looker(&Token::new(token::CloseDelim(delim), span.close)) - } - }; - } - } - - // We are in a more complex case. Just clone the token cursor and use - // `next`, skipping delimiters as necessary. Slow but simple. + // Just clone the token cursor and use `next`, skipping delimiters as + // necessary. Slow but simple. let mut cursor = self.token_cursor.clone(); let mut i = 0; let mut token = Token::dummy(); diff --git a/compiler/rustc_parse/src/parser/tests.rs b/compiler/rustc_parse/src/parser/tests.rs index 538ec6b8cfd..5b2d119e42b 100644 --- a/compiler/rustc_parse/src/parser/tests.rs +++ b/compiler/rustc_parse/src/parser/tests.rs @@ -1424,12 +1424,15 @@ fn look_ahead() { look!(p, 1, token::Colon); look!(p, 2, token::Ident(sym::u32, raw_no)); look!(p, 3, token::CloseDelim(Delimiter::Parenthesis)); - // FIXME(nnethercote) If we lookahead any distance past a close delim - // we currently return that close delim. - look!(p, 4, token::CloseDelim(Delimiter::Parenthesis)); - look!(p, 5, token::CloseDelim(Delimiter::Parenthesis)); - look!(p, 6, token::CloseDelim(Delimiter::Parenthesis)); - look!(p, 100, token::CloseDelim(Delimiter::Parenthesis)); + look!(p, 4, token::OpenDelim(Delimiter::Brace)); + look!(p, 5, token::Ident(sym_x, raw_no)); + look!(p, 6, token::CloseDelim(Delimiter::Brace)); + look!(p, 7, token::Ident(kw::Struct, raw_no)); + look!(p, 8, token::Ident(sym_S, raw_no)); + look!(p, 9, token::Semi); + look!(p, 10, token::Eof); + look!(p, 11, token::Eof); + look!(p, 100, token::Eof); // Move forward to the `;`. for _ in 0..9 { @@ -1454,12 +1457,13 @@ fn look_ahead() { }); } -/// FIXME(nnethercote) Currently there is some buggy behaviour when using -/// `look_ahead` not within the outermost token stream, as this test shows. +/// There used to be some buggy behaviour when using `look_ahead` not within +/// the outermost token stream, which this test covers. #[test] fn look_ahead_non_outermost_stream() { create_default_session_globals_then(|| { let sym_f = Symbol::intern("f"); + let sym_x = Symbol::intern("x"); #[allow(non_snake_case)] let sym_S = Symbol::intern("S"); let raw_no = IdentIsRaw::No; @@ -1475,20 +1479,21 @@ fn look_ahead_non_outermost_stream() { look!(p, 0, token::Ident(kw::Fn, raw_no)); look!(p, 1, token::Ident(sym_f, raw_no)); look!(p, 2, token::OpenDelim(Delimiter::Parenthesis)); - // FIXME(nnethercote) The current code incorrectly skips the `x: u32)` - // to the next token tree. - look!(p, 3, token::OpenDelim(Delimiter::Brace)); - // FIXME(nnethercote) The current code incorrectly skips the `x }` - // to the next token tree. - look!(p, 4, token::Ident(kw::Struct, raw_no)); - look!(p, 5, token::Ident(sym_S, raw_no)); - look!(p, 6, token::Semi); - // FIXME(nnethercote) If we lookahead any distance past a close delim - // we currently return that close delim. - look!(p, 7, token::CloseDelim(Delimiter::Brace)); - look!(p, 8, token::CloseDelim(Delimiter::Brace)); + look!(p, 3, token::Ident(sym_x, raw_no)); + look!(p, 4, token::Colon); + look!(p, 5, token::Ident(sym::u32, raw_no)); + look!(p, 6, token::CloseDelim(Delimiter::Parenthesis)); + look!(p, 7, token::OpenDelim(Delimiter::Brace)); + look!(p, 8, token::Ident(sym_x, raw_no)); look!(p, 9, token::CloseDelim(Delimiter::Brace)); - look!(p, 100, token::CloseDelim(Delimiter::Brace)); + look!(p, 10, token::Ident(kw::Struct, raw_no)); + look!(p, 11, token::Ident(sym_S, raw_no)); + look!(p, 12, token::Semi); + look!(p, 13, token::CloseDelim(Delimiter::Brace)); + // Any lookahead past the end of the token stream returns `Eof`. + look!(p, 14, token::Eof); + look!(p, 15, token::Eof); + look!(p, 100, token::Eof); }); } |