structuredClone invokes custom Map and Set iterators

[OskarEichler]

Description

The React Native structuredClone polyfill traverses Map and Set values with for...of. An own Symbol.iterator override is therefore executed and can change the cloned contents or abort cloning, even though structured cloning should read the built-in collection data from internal slots.

Expected behavior

Map and Set cloning should ignore user iterator overrides and clone their real built-in entries, 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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