fix: Background threads leaking across tests#229
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The polling and streaming worker threads could outlive the test that created them. Once leaked, they raced with pyfakefs (which is not thread-safe) during another test's filesystem patching, corrupting it, and pytest 9 turns the resulting unhandled thread exceptions into test errors. This surfaced as flaky failures on the pytest 7->9 bump (#228). - polling_manager: wait on the stop event instead of time.sleep so stop() interrupts the interval immediately and the thread joins promptly, and guard update_environment so an unexpected error never kills the thread. - streaming_manager: catch any exception in the run loop rather than a fixed tuple, so the thread never propagates an unhandled exception. - tests: join (not just stop) the threads on teardown so none outlive their test, and keep the realtime test's stream worker off the network. beep boop
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This pull request improves thread management and error handling in the polling and streaming managers. Specifically, it replaces time.sleep with _stop_event.wait in the polling manager for immediate interruption, catches generic exceptions in both managers to prevent threads from dying, and joins background threads during test teardown to avoid race conditions with pyfakefs. The review feedback suggests adding a wait interval in the streaming manager's exception handler to prevent a high-CPU busy loop, and joining the event processor thread during test teardown to ensure proper cleanup.
matthewelwell
approved these changes
Jun 26, 2026
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Background worker threads could outlive the test that created them, then race with pyfakefs in a later test. This never surfaced until #228 because pytest 9 turns the resulting unhandled thread exceptions into test errors.
The changes here are version-agnostic and pass on both pytest 7.4.4 (current main) and pytest 9.0.3.
Testing:
-W error).