structuredClone preserves Error cause references and drops falsy causes

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

Commencez par localiser le polyfill structuredClone de React Native et examinez la manière dont il gère Error.cause. Comparez son comportement avec celui de structuredClone natif de Node, puis ajoutez une couverture de tests montrant le clonage récursif, la préservation de l’identité circulaire/partagée, le descripteur non énumérable et les causes falsy.