Fix flaky EventTargetDispatching-itest error handling test#57042
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cortinico wants to merge 2 commits into
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Fix flaky EventTargetDispatching-itest error handling test#57042cortinico wants to merge 2 commits into
EventTargetDispatching-itest error handling test#57042cortinico wants to merge 2 commits into
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Summary: Replace tight `sleep_for` margins with a `std::promise`/`std::future` synchronization pattern. The old test used `sleep_for(50ms)` and `sleep_for(70ms)` to bracket a 100ms delayed task, which failed on loaded CI machines when timers fired early or late (98.7% flakiness score). The new approach uses `sleep_for(20ms)` for the "not yet executed" check (well before the 200ms delay) and `future.wait_for(5s)` for the "completed" check, eliminating timing sensitivity entirely. Changelog: [Internal] Differential Revision: D107232190
Summary:
When `enableNativeEventTargetEventDispatching` is enabled, `EventTarget.js` defers handler errors via `setTimeout(0)` in `reportListenerError`, making them non-deterministically visible to a synchronous `toThrow` assertion (96.6% flakiness score). When `toThrow` misses the error, it leaks as an uncaught exception into the next test ("event timestamps"), causing a cascade failure.
Gate the `toThrow` assertion on the legacy code path where errors propagate synchronously via `rethrowCaughtError`. In the new EventTarget path, dispatch the event and drain any pending errors via `Fantom.runTask` to prevent test pollution. The core assertion (`parentHandler` called despite child error) runs in both paths.
Changelog: [Internal]
Differential Revision: D107232191
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Summary:
When
enableNativeEventTargetEventDispatchingis enabled,EventTarget.jsdefers handler errors viasetTimeout(0)inreportListenerError, making them non-deterministically visible to a synchronoustoThrowassertion (96.6% flakiness score). WhentoThrowmisses the error, it leaks as an uncaught exception into the next test ("event timestamps"), causing a cascade failure.Gate the
toThrowassertion on the legacy code path where errors propagate synchronously viarethrowCaughtError. In the new EventTarget path, dispatch the event and drain any pending errors viaFantom.runTaskto prevent test pollution. The core assertion (parentHandlercalled despite child error) runs in both paths.Changelog: [Internal]
Differential Revision: D107232191