Every cancel in app/src/androidTest is WorkManager.cancelWorkById against
work that is queued or already finished: ReattachOnLaunchTest cancels a job
carrying a one-hour initial delay, and another immediately after enqueue.
On the JVM, WorkerCancellationTest and HardwareFallbackTest's cancellation
case drive a SoftwareTranscoder double that records the call. No test on
any source set had asked a real native session to stop. That is
docs/defect-audit.md D10's forcing condition.
It is the one path where cancelling wrong is silently expensive rather than
loudly broken: a missed FFmpegKit.cancel leaves the native process encoding
to completion while the UI says the job is cancelled.
Two things were measured rather than assumed, and both changed the test.
The output file cannot be the assertion. invokeOnCancellation deletes the
path, and on POSIX unlinking a file ffmpeg still holds open leaves ffmpeg
writing to the unlinked inode -- so the path stays gone whether or not the
cancel reached the session, and removing FFmpegKit.cancel passes that check
every time. The session's own verdict is what separates them: a cancelled
session ends with the cancel return code, a completed one does not.
Cancelling from the first progress callback loses the race. It was tried
first and failed with state=COMPLETED rc=0: every committed fixture is
2-3 s at 320x240, and the encode finishes before the first statistics
callback is delivered and acted on. FFmpegKit.listSessions shows the
session RUNNING far earlier, so that is what the test waits for.
QualityTier.BEST is deliberate for the same reason -- preset medium leaves
more of the encode ahead of the cancel.
Verified on a local API 34 emulator. Four consecutive runs green at
62/0/0/3, and removing FFmpegKit.cancel while keeping output.delete fails
this test and nothing else, with state=COMPLETED rc=1.
ConcatEngine and Media3Engine carry the same shape and are not covered
here; #224 stays open for them.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
JMR-devandClaude Opus 5
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