Add deterministic timer mock to Fantom (#57274)#57274
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Summary: Fantom could not deterministically fire delayed JS timers: the timer registry it used scheduled timers on a real background thread with real wall-clock delays, so `setTimeout(fn, 100)`/`setInterval` callbacks never fired within a synchronous test. This adds a mockable timer registry and a public Fantom API to control it from JS, similar to `installHighResTimeStampMock`. - New `Fantom.installTimerMock()` returns a controller with `advanceTimersByTime(ms)`, `runAllTimers()`, `getPendingTimerCount()`, and `uninstall()` (jest fake-timer style). While installed, `setTimeout`/`setInterval` callbacks only fire when the virtual clock is advanced. - New deterministic `FantomTimerRegistry` (no background thread) keyed off a virtual clock, injected via a new optional `platformTimerRegistryFactory` seam on `ReactInstanceConfig` (the default registry is unchanged for all other consumers). - `PlatformTimerRegistry` gains a virtual `setTimerManager` (default no-op) so the registry can be wired polymorphically. - Control flows from JS through new `NativeFantom` methods, the same way the high-res timestamp mock works. Default (non-mock) behavior is preserved: zero-delay `setTimeout` still fires on the next work loop, and existing tests are unaffected. Changelog: [Internal] Differential Revision: D109017304
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Summary: Fantom could not deterministically fire delayed JS timers: the timer registry it used scheduled timers on a real background thread with real wall-clock delays, so `setTimeout(fn, 100)`/`setInterval` callbacks never fired within a synchronous test. This adds a mockable timer registry and a public Fantom API to control it from JS, similar to `installHighResTimeStampMock`. - New `Fantom.installTimerMock()` returns a controller with `advanceTimersByTime(ms)`, `runAllTimers()`, `getPendingTimerCount()`, and `uninstall()` (jest fake-timer style). While installed, `setTimeout`/`setInterval` callbacks only fire when the virtual clock is advanced. - New deterministic `FantomTimerRegistry` (no background thread) keyed off a virtual clock, injected via a new optional `platformTimerRegistryFactory` seam on `ReactInstanceConfig` (the default registry is unchanged for all other consumers). - `PlatformTimerRegistry` gains a virtual `setTimerManager` (default no-op) so the registry can be wired polymorphically. - Control flows from JS through new `NativeFantom` methods, the same way the high-res timestamp mock works. Default (non-mock) behavior is preserved: zero-delay `setTimeout` still fires on the next work loop, and existing tests are unaffected. Changelog: [Internal] Differential Revision: D109017304
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Summary:
Fantom could not deterministically fire delayed JS timers: the timer registry it used scheduled timers on a real background thread with real wall-clock delays, so
setTimeout(fn, 100)/setIntervalcallbacks never fired within a synchronous test. This adds a mockable timer registry and a public Fantom API to control it from JS, similar toinstallHighResTimeStampMock.Fantom.installTimerMock()returns a controller withadvanceTimersByTime(ms),runAllTimers(),getPendingTimerCount(), anduninstall()(jest fake-timer style). While installed,setTimeout/setIntervalcallbacks only fire when the virtual clock is advanced.FantomTimerRegistry(no background thread) keyed off a virtual clock, injected via a new optionalplatformTimerRegistryFactoryseam onReactInstanceConfig(the default registry is unchanged for all other consumers).PlatformTimerRegistrygains a virtualsetTimerManager(default no-op) so the registry can be wired polymorphically.NativeFantommethods, the same way the high-res timestamp mock works.Default (non-mock) behavior is preserved: zero-delay
setTimeoutstill fires on the next work loop, and existing tests are unaffected.Changelog: [Internal]
Differential Revision: D109017304