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JEST LANDS TEMPORAL AND REACT 19 SUPPORT AS REACT-NATIVE PATCHES ANIMATION CRASHES
By RepoJournal · Filed · About Meta
Jest is shipping forward compatibility for Node 26's Temporal API and React 19 components while fixing critical race conditions in React Native's animation pipeline.
Jest's fake-timers now support Temporal [1], Node's new standard datetime library coming in version 26, giving your tests a path forward before the runtime ships. The same release adds React 19 component support to pretty-format [2], fixing output issues that were technically React's problem but Jest's to solve. Jest is also enforcing import attributes warnings [3] — not throwing yet, but the threshold moves to Jest 31, so audit your test suites now. A new workerGracefulExitTimeout config option [4] lets you control how long worker processes get to exit before forced termination, defaulting to 500ms but now configurable for environments that need breathing room. On the React Native side, 0.312.1 deployed to xplat [5], but the real fixes are in animation threading — a null-check on animationBackend_ [6] prevents crashes on clearRegistry(), while props registry cleanup now happens correctly on the JS thread to avoid race conditions with the main thread [7]. React Native 0.85.3 changelog was finalized , and CI reliability improved after fixing yarn registry references [8] that were breaking installs against the internal registry.
Action items
- → Audit test suites for import attributes usage before Jest 31 ships facebook/jest [plan]
- → Update React Native to 0.312.1+ for animation crash fixes facebook/react-native [plan]
- → Verify Jest worker timeout behavior in your CI if you see unclean exits facebook/jest [monitor]
References
- [1] feat(fake-timers): basic support for `Temporal` ↗ facebook/jest
- [2] feat(pretty-format): support React 19 ↗ facebook/jest
- [3] feat: support import attributes ↗ facebook/jest
- [4] feat: add workerGracefulExitTimeout config option ↗ facebook/jest
- [5] Deploy 0.312.1 to xplat (#56681) facebook/react-native
- [6] Add animationBackend_ nullcheck before calling clearRegistry() (#56679) facebook/react-native
- [7] clear up props registry in shared backend on js thread (#56677) facebook/react-native
- [8] Manually fix references to registry.facebook.net -> registry.yarnpkg.com (#56683) facebook/react-native
FAQ
- What changed in Meta on May 6, 2026?
- Jest is shipping forward compatibility for Node 26's Temporal API and React 19 components while fixing critical race conditions in React Native's animation pipeline.
- What should Meta teams do about it?
- Audit test suites for import attributes usage before Jest 31 ships • Update React Native to 0.312.1+ for animation crash fixes • Verify Jest worker timeout behavior in your CI if you see unclean exits
- Which Meta repositories shipped on May 6, 2026?
- facebook/jest, facebook/react-native