fix(tests): make useStoreRehydrated suspense test deterministic#1032
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fix(tests): make useStoreRehydrated suspense test deterministic#1032
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The test relied on a setTimeout-based async memory storage (18ms wait) to keep the rehydration promise pending while asserting the Suspense fallback. Under coverage instrumentation in CI the timer could fire inside the surrounding act() block, so React unsuspended before the Loading assertion ran. Switches to a manually-controlled deferred promise so the rehydration gate is held until the test explicitly releases it. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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The test relied on a setTimeout-based async memory storage (18ms wait) to keep the rehydration promise pending while asserting the Suspense fallback. Under coverage instrumentation in CI the timer could fire inside the surrounding act() block, so React unsuspended before the Loading assertion ran. Switches to a manually-controlled deferred promise so the rehydration gate is held until the test explicitly releases it. Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Summary
The
useStoreRehydratedtest in `tests/persist.test.js` is flaky undercoverage instrumentation in CI — it failed on the v7 release PR (#1031).
The test relied on a setTimeout-based async memory storage (18ms) to keep
the rehydration promise pending while asserting the Suspense fallback.
Under coverage instrumentation the timer can fire inside the surrounding
`act()` block, so React unsuspends and the `Loading...` assertion fails
with `expected null not to be null`.
Changes
manually-controlled deferred promise. The rehydration gate is held until
the test explicitly releases it, removing the timing race.