Bug: Potential misuse of NoLanes in executionContext check in scheduleUpdateOnFiber

[0xFANGO]

React version:

19.2.0

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Steps To Reproduce

1. Go to [scheduleUpdateOnFiber](https://github.com/facebook/react/blob/main/packages/react-reconciler/src/ReactFiberWorkLoop.js) function in react-reconciler

2. Find this line:

   if ((executionContext & RenderContext) !== NoLanes && root === workInProgressRoot)

3. Notice that executionContext is a set of context flags (bitmask), while NoLanes refers to lane priorities and is not used in context checks anywhere else

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Link to code example

No runtime code needed — this is a logic-level mismatch in the internal source file.

Relevant file:

• packages/react-reconciler/src/ReactFiberWorkLoop.js

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❌ The current behavior

The line:

(executionContext & RenderContext) !== NoLanes

uses NoLanes in a bitmask comparison with executionContext, which is inconsistent with surrounding usages that compare with NoContext.

NoLanes is defined in the Lane system and is intended for scheduling lanes, not execution contexts.

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✅ The expected behavior

This line should likely be:

(executionContext & RenderContext) !== NoContext

This matches similar checks throughout the codebase and would avoid incorrect context evaluation.

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[github-actions]

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