react / react/react-native

structuredClone coerces boxed primitives and flips false Boolean

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Dominant language
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Description

Description

The React Native structuredClone polyfill reconstructs Number, String, Boolean, and Date wrappers by passing the source object to a constructor. Number/String cloning invokes user coercion hooks, and new Boolean(new Boolean(false)) uses object truthiness and silently changes the internal value to true.

Expected behavior

Cloning should read each wrapper's internal primitive through the built-in valueOf intrinsic, create a distinct wrapper with the same value, and never execute user coercion. Native structuredClone follows this behavior.

React Native Version

0.87.1 and current main

Affected Platforms

JavaScript runtime - All

Contributor guide

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First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start at the React Native structuredClone polyfill entry point and reproduce the behavior with boxed Number, String, Boolean, and Date values. Check that cloning reads the internal primitive without running user coercion hooks, preserves false Boolean values, and creates distinct wrappers; compare the result with native structuredClone.

Written by the indexing model from the issue text.

Assessment

Tech stack
javascript, react-native
Domain
mobile
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Active
Clarity
Mostly clear
Newbie friendliness
68/100

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