#84 closed by classifying probeWithExtractor and probeForConcat as
device-bound and explicitly not a gap. That was right about FFprobe and
right about the measurement boundary, and wrong that these are only
orchestration. The track walk is a branch matrix, and androidTest reaches
it only through whatever the committed fixtures happen to contain -- so
none of its rules is *chosen* by any test there.
#133 offered two ways to reach it: drive ShadowMediaExtractor, or cut the
loop into a pure function. Taking the second, which is the pattern
CLAUDE.md names and work/FailureOutcome.kt documents. extractedFrom and
concatInputFrom take List<MediaFormat>; what is left needing a device --
setDataSource, getTrackFormat, release -- is one three-line extension
function, which is the thin edge androidTest should be covering.
The two are deliberately not merged despite the overlap. One reads
duration and not frame rate; the other reads frame rate and not duration.
A merged version would compute both for every caller, and ConcatPlanner
treats an unknown frame rate as "cannot prove a match" -- so a field the
join flow does not need must not start arriving as a number.
Eleven tests over cases no fixture provides: two video tracks, two audio
tracks, audio outlasting video, a track with no KEY_DURATION, audio
declared before video, a subtitle track, and no tracks at all.
Six mutations, six red:
last video track wins first-video test
last audio track wins first-audio test
duration = last rather than max longest-track test
drop the containsKey guard six tests (getLong throws on a missing key)
guess a frame rate of 30 no-frame-rate test
join takes the last video track join frame-rate test
MediaProbe's missed branches drop 91 -> 70; what is left is the FFprobe
half and the two catch arms, which are native and device-bound exactly as
#84 said.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
