fix(es/minifier): Preserve __proto__ shorthand property behavior
#11123
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When minifying object shorthand properties, the `__proto__` property should be converted to a computed property `["__proto__"]` instead of a regular key-value pair to preserve the original object behavior. This prevents changing the object's prototype chain during minification.
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CodSpeed Performance ReportMerging #11123 will not alter performanceComparing Summary
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Pull Request Overview
This PR fixes a bug in the ECMAScript minifier where __proto__ shorthand properties were being converted to regular key-value pairs, which incorrectly modified the object's prototype chain. The fix ensures __proto__ shorthand properties are converted to computed properties ["__proto__"] to preserve their original behavior.
- Adds special handling for
__proto__in shorthand property conversion - Converts
__proto__shorthand to computed property syntax instead of regular identifier - Preserves object prototype chain behavior during minification
Reviewed Changes
Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.
| File | Description |
|---|---|
| crates/swc_ecma_minifier/src/compress/optimize/util.rs | Implements the core fix across three visitor implementations to handle __proto__ shorthand conversion |
| crates/swc_ecma_minifier/tests/fixture/issues/11105/input.js | Test input demonstrating the issue with __proto__ shorthand |
| crates/swc_ecma_minifier/tests/fixture/issues/11105/output.js | Expected output showing __proto__ converted to computed property |
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… and improve maintainability
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Pull Request Overview
Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.
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| expr: Box::new(Expr::Lit(Lit::Str(Str { | ||
| span: ident.span, | ||
| value: ident.sym.clone(), | ||
| raw: None, |
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[nitpick] Consider using Some(format!("\"{}\"", ident.sym)) instead of None for the raw field to maintain consistent string literal formatting in the generated code.
| raw: None, | |
| raw: Some(format!("\"{}\"", ident.sym)), |
4 participants
Description:
When minifying object shorthand properties, the
__proto__property should be converted to a computed property["__proto__"]instead of a regular key-value pair to preserve the original object behavior. This prevents changing the object's prototype chain during minification.BREAKING CHANGE:
Related issue (if exists):
var __proto__ = []; console.log({ __proto__ })is wrongly compressed toconsole.log({ __proto__: [] })#11105