testing-animations-deterministically

Fix flaky Jetpack Compose animation UI tests by pausing the MainTestClock with mainClock.autoAdvance = false before setContent, then manually stepping frames with advanceTimeByFrame(). This makes animation timing deterministic across CI and local environments.

Compose tests throw CancellationException when infinite animations trigger the InfiniteAnimationPolicy. Prevent this by disabling mainClock.autoAdvance and manually stepping the animation frames to keep indeterminate progress indicators safely controlled.

Test intermediate animation frames by setting mainClock.autoAdvance = false before setContent, calling advanceTimeByFrame() to start, and using advanceTimeBy(durationMillis) to step the animation before asserting the intermediate UI state.

Use runOnUiThread to mutate Compose state while the test clock is paused. runOnUiThread avoids mid-animation race conditions and test hangs that occur when attempting state mutations on idle during paused-clock Compose animation testing.

Use mainClock.advanceTimeUntil { ... } to wait for Compose-observable conditions during paused animation tests. Prefer advanceTimeUntil over wall-clock waitUntil to properly evaluate state conditions inside the paused-clock window.