Bug: quickfiler-tests-depend-on-wall-clock-timing #950

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1. drmoisan

   added

   bugSomething isn't workingSomething isn't working

   on Sep 30, 2026
2. drmoisan commented on Sep 30, 2026

   

   drmoisan

   on Sep 30, 2026

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   Restoring sections dropped by the promotion tooling.

   Suspected Cause / Notes

   Real-time bounded waits violate the repository determinism rules: no wall-clock waits in tests, and use of FakeTimeProvider or a controllable scheduler.

   • QfcDatamodelLivenessTests.cs uses SpinWait.SpinUntil(..., TimeSpan.FromSeconds(5)) (line ~56) and .Task.Wait(TimeSpan.FromSeconds(5)) (lines ~103 and ~173).
   • The transaction test (QfcItemController.UiThreadDispatcherFixtureTests.cs:206) may be a different root cause. Triage it first, and split it into its own issue if its cause is not timing.

   This hits a required check. #944 needed a one-time gate re-run because of it.

   Proposed Fix / Validation Ideas

   • Replace the bounded waits with deterministic completion signals (TaskCompletionSource or awaited handles) or an injected TimeProvider.
   • Use no retries, [DoNotParallelize], Workers=1 or longer timeouts, and find any raced static state.
   • Negative control: show that each rewritten test fails when the awaited signal is never set.
3. drmoisan commented on Oct 1, 2026

   

   drmoisan

   on Oct 1, 2026

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   Scope note from the #950 preparation research.

   The same bounded wall-clock wait pattern also exists in:

   • QuickFiler.Test/Controllers/QfcDatamodelTeardownTests.cs
   • QuickFiler.Test/Controllers/QfcInitEmailQueueZeroBatchTests.cs

   Both waits come from the same cause: QfcDatamodel.InitEmailQueue starts its worker on a thread pool the test cannot control. Fix them with the same seam #950 introduces. They can be included in #950's scope, or taken on in a follow-up branch immediately after #950 merges.

   The research also found that the transaction test failure (Transaction_SecondCallerCannotInstallUntilTheFirstRestores) has a different cause: UiThreadDispatcherFixture.EnsureDispatcher() replaces the shared dispatcher without taking the lock that guards it, while QfcItemController_FocusAndThemeTests runs in parallel. The proposed fix changes only test code and stays within #950.
4. drmoisan

   closed this as completedin #971on Oct 2, 2026