Repository navigation
structuredClone preserves Error cause references and drops falsy causes #58206
Description
Description
The React Native structuredClone polyfill passes Error.cause through by reference instead of cloning it, and only copies the property when its value is truthy. Object causes therefore remain shared with the input; a circular cause points back to the original Error; and valid falsy causes such as false disappear.
Expected behavior
An own cause property should be cloned recursively, retain its non-enumerable Error property descriptor, preserve circular/shared identity within the clone, and keep falsy values. Node's native structuredClone follows this behavior.
React Native Version
0.87.1 and current main
Affected Platforms
JavaScript runtime - All
Activity
react-native-bot commentedon Aug 30, 2026
Warning
Missing reproducer: We could not detect a reproducible example in your issue report. Reproducers are mandatory and we can accept only one of those as a valid reproducer:
You can read more about about it on our website: How to report a bug.
react-native-bot commentedon Sep 24, 2026
This issue is waiting for author's feedback since 24 days. Please provide the requested feedback or this will be closed in 7 days.
OskarEichler commentedon Oct 2, 2026
Added the requested runnable RNTester Playground in #58806. Open Playground and press Run reproducers; the result for #58206 is labeled separately.
Verified using the native Hermes/Fabric Fantom runner on main
cd2de187e8878119896159371225acbb9dfa5d9c. Error cause cases now PASS: object causes are cloned and a false cause is preserved. This no longer reproduces on current main.This is a constructed example based on the source audit, not a claimed production incident. The PR includes the exact native verification driver and results.