fix(codegen): wrap TSAsExpression in parens when used with in/instanceof operators#17752
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TSAsExpression in parens when used with in/instanceof operators
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Pull request overview
This PR fixes a code generation bug where TypeScript as expressions were not being wrapped in parentheses when used with the in or instanceof operators, leading to incorrect output that would fail to parse correctly on subsequent passes.
- Changed the wrapping threshold for
TSAsExpressionfromPrecedence::ShifttoPrecedence::Compareto includeinandinstanceofoperators - Added comprehensive tests using a new
test_idempotencyhelper function that verifies codegen stability across multiple passes
Reviewed changes
Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.
| File | Description |
|---|---|
crates/oxc_codegen/src/gen.rs |
Updated TSAsExpression::gen_expr to wrap expressions at Precedence::Compare instead of Precedence::Shift, correctly handling in and instanceof operators |
crates/oxc_codegen/tests/integration/tester.rs |
Added new test_idempotency function to verify that codegen produces stable output when parsing and regenerating code multiple times |
crates/oxc_codegen/tests/integration/ts.rs |
Added comprehensive test cases for as expressions with in and instanceof operators, including nested cases |
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### 🚀 Features - 10426af codegen: Print soft space between inline block comments on the same line (#17799) (camc314) - 2261e6e semantic: Improve error message to add `#` for private identifiers (#17779) (Dunqing) ### 🐛 Bug Fixes - 7422b7e parser/trivia: Correctly mark whether a block comment is on a newline (#17754) (camc314) - c32e8d5 codegen: Wrap `TSAsExpression` in parens when used with in/instanceof operators (#17752) (camc314) - 5755b2d semantic: Report duplicate private identifier for static and instance elements (#17591) (camc314) - 0600df3 isolated_declarations: Only print jsdoc comments (#17748) (camc314) - ef7e014 parser: Preserve `@__NO_SIDE_EFFECTS__` annotation with parenthesized expressions (#17711) (camc314) - 59a6228 parser: Detect TS1363 error for type-only imports with mixed default and named/namespace bindings (#17712) (Copilot) ### ⚡ Performance - 864f1fa semantic: Mark duplicate class element error reporting as cold (#17746) (camc314) - 3a452b8 semantic: Use smallvec for storing reference IDs (#17731) (camchenry) - d5979dc minifier: Do not allocate when checking to convert `const` to `let` (#17730) (camchenry) - 3f4429c parser: Do not re-allocate TS interface heritage (#17692) (camchenry) ### 📚 Documentation - 120a27c minifier: Add prettier-ignore for js-in-md part (#17687) (leaysgur) Co-authored-by: Boshen <1430279+Boshen@users.noreply.github.com>
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