fix: make thread assertion tests deterministic - #4570
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thomhurst merged 1 commit intoJan 27, 2026
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fix: make thread assertion tests deterministic#4570thomhurst merged 1 commit intomainthomhurst/TUnit:mainfrom fix/flaky-thread-assertion-teststhomhurst/TUnit:fix/flaky-thread-assertion-testsCopy head branch name to clipboard
thomhurst merged 1 commit into
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Replace Thread.Sleep() with ManualResetEventSlim synchronization to ensure threads stay alive until assertions complete. This fixes flaky test failures where ThreadStateException was thrown because the thread completed before IsThreadPoolThread could be accessed. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
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SummaryFixes flaky thread assertion tests by replacing timing-based synchronization (Thread.Sleep) with deterministic event-based synchronization (ManualResetEventSlim). Critical IssuesNone found ✅ The changes correctly address the race condition that was causing ThreadStateException: Thread is dead; state cannot be accessed. The new pattern ensures:
SuggestionsNone - the implementation is clean and follows proper synchronization patterns. Verdict✅ APPROVE - No critical issues The PR fixes a legitimate test flakiness issue with proper synchronization primitives. The duplicate import removal is a nice cleanup bonus. |
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Summary
Test_Thread_IsNotThreadPoolThread_NewThreadtest that was failing withThreadStateException: Thread is dead; state cannot be accessedThread.Sleep()withManualResetEventSlimsynchronization inTest_Thread_IsAlive_NewThread,Test_Thread_IsBackground_Started, andTest_Thread_IsNotThreadPoolThread_NewThreadusing TUnit.Assertions.Extensions;importTest plan
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