[CHORE] Fix race condition in SwiftTestingTraitTests mock SessionManager#249
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…Tests The trait test's verification blocks run concurrently across top-level scopes. When the last-finishing scope called stop(), _session was nilled, so a slower verifier awaiting through sessionAndConfig would bootstrap a fresh empty session — making session.modules[test.ddModule]?.suites[...] nil. Keep the session reference after stop() and gate observer notifications with a _stopped flag so the side effects only fire once. Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>
ypopovych
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ypopovych
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juan-fernandez
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May 14, 2026
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Summary
Expectation failed: session.modules[test.ddModule]?.suites[test.ddSuite] → nilinSwiftTestingTraitTests.provideScopeverification blocks run concurrently across the file's top-level scopes (2 suites + 3 free@Testfuncs). When the scope ending the module calledstop(),Mocks.SessionManagernilled_session. A slower verifier awaitingsuiteProvider.session.sessionafter that point would re-entersessionAndConfigand bootstrap a brand-new empty session viaprovider.startSession, so the subsequentsession.modules[...]?.suites[...]lookup returned nil._sessionset afterstop()and gate the observer notifications with a_stoppedflag so willFinish/didFinish/end still fire exactly once. Concurrent readers post-stop now observe the same (now-ended) session instead of a fresh one.Test plan
xcodebuild test-without-buildingforSwiftTestingTraitTests,SwiftTestingTaggedSuiteTests,testFuncRetryErrorShouldFail,testFuncRegistration,zzzzFuncCancel— 10 consecutive runs all pass, nosession.modules → nilfailures.🤖 Generated with Claude Code