[tjzel]

Note

This pull request was authored by AI on behalf of @tjzel.

Summary

Follow-up to #11003, #10919 and #10920.

The Jest mocks of makeMutable, useScrollOffset, useScrollViewOffset and useTimestamp returned plain values instead of shared values. isSharedValue(makeMutable(0)) was false, and code that called addListener on a scroll offset or a timestamp crashed under the mock.

I moved the useSharedValue Proxy into a createMockSharedValue factory and used it in all of these mocks. useScrollOffset and useTimestamp keep one shared value per component with useState, like useSharedValue, and useScrollOffset returns the provided offset when one is passed, like the real hook.

Test plan

yarn workspace react-native-reanimated jest mock.sharedValueFactories runs the new tests, which fail without the change and pass with it.

Changelog

• I added a changelog fragment with yarn changelog:add for each changed package, or this PR does not change react-native-reanimated or react-native-worklets.

[coderabbitai]

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Commits

Reviewing files that changed from the base of the PR and between ceefd82 and 23262f7.

Files selected for processing: 2

• packages/react-native-reanimated/__tests__/mock.sharedValueFactories.test.tsx
• packages/react-native-reanimated/src/mock.ts

Files skipped from review as they are similar to previous changes: 2

• packages/react-native-reanimated/src/mock.ts
• packages/react-native-reanimated/tests/mock.sharedValueFactories.test.tsx

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Walkthrough

The Jest mocks now use a shared helper to create values with value, get, set, modify, listener methods, and a shared-value marker. Scroll-offset hooks, useSharedValue, useTimestamp, and makeMutable use these mock values. Tests check mutation, listener operations, stability across rerenders, and preservation of a supplied scroll offset.

Possibly related issues

• software-mansion/react-native-reanimated#11002 — This issue reports that subscribing to a mocked shared value fails when addListener is missing. This change adds no-op listener methods to mock values created by the affected factories.

Possibly related PRs

• software-mansion/react-native-reanimated#10919 — This change retains the lazy initializer behavior for the mocked useSharedValue while moving initialization into the shared factory.
• software-mansion/react-native-reanimated#11003 — This change reuses the shared-value methods, including modify and listener methods, that PR added to the useSharedValue mock.
• software-mansion/react-native-reanimated#10847 — This change adds the shared-value marker to mock values created by additional factories.

Priority: Normal

Change: Bug fix

Merge Risk: Minimal · up to 23262

The reviewed mock behavior matches the checked shared-value and scroll-offset contracts; no issue identified here blocks merging.

Pre-merge checks: 4

Check name	Status	Explanation
Title check		The title clearly and concisely describes the main change: updating Reanimated Jest mocks to return full shared values for the affected APIs.
Description check		The description directly explains the mock behavior change, affected APIs, implementation approach, tests, and changelog update.
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.

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Actionable comments posted: 1

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Reviewing files that changed from the base of the PR and between caa7882 and ceefd82.

Files selected for processing: 3

• packages/react-native-reanimated/__tests__/mock.sharedValueFactories.test.tsx
• packages/react-native-reanimated/changelog/mock-shared-value-factories.fix.md
• packages/react-native-reanimated/src/mock.ts

Included review availability: This review used your included allowance. Your plan provides up to 10 included reviews per hour; 8 remain after this review.