structuredClone reads user-overridden RegExp properties

[OskarEichler]

Description

The React Native structuredClone polyfill reads value.source and value.flags, so own overrides replace a RegExp's internal pattern/flags while cloning. Capturing only the aggregate flags getter is also insufficient because it reads user-visible per-flag properties such as global.

Expected behavior

RegExp cloning should read the built-in internal source and canonical d g i m s u v y flags without invoking or trusting own overrides, matching native structuredClone.

React Native Version

0.87.1 and current main

Affected Platforms

JavaScript runtime - All

[react-native-bot]

Warning

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