react / react/react-native

NodeList.forEach drops an explicit null callback context

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Dominant language
C++
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Avg merge
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Description

Description

NodeList.forEach treats both null and undefined as the omitted thisArg fast path. An explicitly supplied null is therefore discarded, and a strict callback receives undefined instead of null, unlike standard Array and NodeList behavior.

Expected behavior

Only an omitted/undefined thisArg should use the unbound callback path. Explicit null should be forwarded as the callback receiver.

React Native Version

0.87.1 and current main

Affected Platforms

JavaScript runtime - All

Contributor guide

Open the contributing guide

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 NodeList.forEach implementation and trace how null and undefined thisArg values are handled. Add or update coverage for an explicitly null callback context, then verify that strict callbacks receive null while omitted or undefined contexts retain the existing behavior.

Written by the indexing model from the issue text.

Assessment

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

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