Fix cascading parse errors for parenthesized expressions at top level#9059
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Fix cascading parse errors for parenthesized expressions at top level#9059
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When encountering a parenthesized expression like (x = 5).foo() at the top level of a module, the parser now skips past the entire expression and produces a single parse error instead of producing multiple statement_unexpected_token errors for each token. Previously, the parser would not consume any tokens when it detected that a parenthesized construct at top level was not a destructuring pattern, causing it to produce cascading errors for each token. Fixes #9046 Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
When skipping a parenthesized expression at top level, the lookahead loop might hit EndOfFile before finding the matching close paren. In this case, we should not try to advance past the EOF token as that would cause an assertion failure in peek(). Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
After skipping a parenthesized expression at top level, we need to back up one position before calling pushMalformed because pushMalformed always advances. This ensures the parser doesn't skip past the first token of the next statement, which would cause cascading errors. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
The parser fix reduces cascading errors when encountering parenthesized expressions at top level. This test now only has 2 parse errors instead of 6, as the ( tokens are no longer processed individually but skipped as a group. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
The parser fix reduces cascading errors when encountering parenthesized expressions at top level. These snapshot tests now reflect the improved behavior with fewer parse errors. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
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Summary
When encountering a parenthesized expression like
(x = 5).foo()at the top level of a module, the parser now produces a single parse error instead of cascading errors for each token.statement_unexpected_tokenerror pointing to the opening parenthesisFixes #9046
Co-authored by Claude Opus 4.5