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Lower property escapes without removing Unicode flags (#59633) - #59633
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Summary: ## Why Hermes builds can support Unicode regex mode without enabling Unicode property escapes. Leaving property escapes in the generated code then causes invalid-escape compilation errors. Lowering the entire Unicode regex instead also removes code-point semantics, which can make a valid astral letter match the surrogate category. ## What The stable and canary presets expand Unicode property escapes in regex literals while retaining the Unicode flag. Ordinary Unicode regexes, class syntax and other profile options stay intact. Other profiles retain their existing transforms. Matching maps are generated normally from the transformed AST; no profile or source-map subtarget is changed. ## How Select Babel's property-escape transform using its default Unicode-flag mode for the Hermes V1 profiles, declare its direct dependency and regenerate the preset expectations. Regression tests exercise the actual transformer and Metro's source-map consumer, including astral letters, property complements, emoji, Unicode categories, normalization and the original position of a call after an expanded regex. Changelog: [General][Fixed] - Retain Unicode regex semantics while lowering property escapes for Hermes builds Reviewed By: javache Differential Revision: D128332799
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This pull request was successfully merged by @andrewdacenko in 6e22123 When will my fix make it into a release? | How to file a pick request? |
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Summary:
Why
Hermes builds can support Unicode regex mode without enabling Unicode property escapes. Leaving property escapes in the generated code then causes invalid-escape compilation errors. Lowering the entire Unicode regex instead also removes code-point semantics, which can make a valid astral letter match the surrogate category.
What
The stable and canary presets expand Unicode property escapes in regex literals while retaining the Unicode flag. Ordinary Unicode regexes, class syntax and other profile options stay intact. Other profiles retain their existing transforms. Matching maps are generated normally from the transformed AST; no profile or source-map subtarget is changed.
How
Select Babel's property-escape transform using its default Unicode-flag mode for the Hermes V1 profiles, declare its direct dependency and regenerate the preset expectations. Regression tests exercise the actual transformer and Metro's source-map consumer, including astral letters, property complements, emoji, Unicode categories, normalization and the original position of a call after an expanded regex.
Changelog:
[General][Fixed] - Retain Unicode regex semantics while lowering property escapes for Hermes builds
Reviewed By: javache
Differential Revision: D128332799