ConverterScreen.kt:668's null arm -- DetailRow("Container", probe.container?.label ?:
"Unknown") in the VIDEO branch -- had never rendered. Every video case in FileCardTest uses
VIDEO_PROBE, which carries container = MP4.
The argument for adding it is the asymmetry, not the coverage. FileCard renders that exact
expression twice, once in AUDIO_ONLY (:660) and once in VIDEO (:668), and "an audio-only
file nothing else could describe degrades one row at a time" drives only the first. Same
expression, same fallback, one kind covered and one not -- which is the same argument
CLAUDE.md records for including ContainerCapabilities:94.
Nor is null an edge case here. InputProbe.container's own KDoc says MediaExtractor cannot
report a container at all, so it comes from FFprobe alone: any run where FFprobe did not
answer produces exactly this shape -- real codec, real dimensions, real duration, no
container. An empty value in its place would read as a rendering bug rather than as a
probe that got half its sources.
The other three rows are asserted alongside, which is what keeps this from being a copy of
the audio-only case. There, everything is unknown at once; here one field is missing from
a probe that is otherwise complete, and the rest have to be unaffected by it.
Mutation: `?: "Unknown"` -> `?: ""` at :668 only, run and restored. The AUDIO_ONLY twin at
:660 is a separate expression, and mutating that one would redden the existing test instead
-- which would prove nothing about this one.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
audioArgs' Drop arm -- `AudioPlan.Drop -> listOf("-an")` -- was ci == 0. The suite's only
-an assertion lives in "gif generates a palette to avoid banding and drops audio", and that
one comes from the image path at FFmpegCommandBuilder.kt:79/:90, which emits -an directly
and never reaches audioArgs. Two sites, one string, one tested.
It is a live path rather than defensive code. AdvancedPicker renders all of
AudioCodec.entries including NONE, ContainerCapabilities.validate permits audio-off whenever
the input has video, and MKV routes the job to FFmpeg -- so "convert this and drop the
soundtrack" is something a user can do today and nothing had built the command for.
Both halves are asserted, and the second is not padding: -an alone still passes if the arm
falls through to the else and emits an AAC encoder beside the flag, which is a file that is
silent because the flag won while carrying an encoder nobody asked for.
Three mutations, all run and restored. The third is the one that justifies the second
assertion, since the first two break -an as a side effect and so cannot show it:
Drop -> emptyList() red
Drop -> the else arm's aac encoder red (loses -an as well)
Drop -> listOf("-an", "-c:a", "aac") red -- -an intact, caught by assertFalse
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Three sites, all ci == 0 before this, and all the same rule:
work/ConversionWorker.kt:316 cause.message ?: GENERIC_FAILURE_MESSAGE
convert/ConversionViewModel.kt:631 e.message ?: SAVE_FAILED_MESSAGE
join/JoinViewModel.kt:416 e.message ?: SAVE_FAILED_MESSAGE
Every existing test throws WITH a message, so the right-hand side had never been evaluated
anywhere in the suite. A Throwable carrying none is not exotic: RuntimeException(),
IOException() and most platform exceptions raised without an argument all have a null
message, and a native engine that dies is exactly where one comes from.
The worker case needed care, and the care is the reason it survived three waves.
ConversionStateMappingTest's "a failure with nothing said still says something" looks like
it covers that site and does not -- it drives the READ side, map(FAILED, Data.EMPTY), and
that side has a fallback of its own at ConversionViewModel.kt:147-149 which turns a blank
KEY_ERROR back into the same constant. So a test asserting on the resulting Failed state
stays green while the worker's fallback is broken. Measured rather than reasoned: with
:316 mutated to .orEmpty(), exactly ONE of 587 tests went red, and it was the new one.
Everything else, including the test that appears to cover it, stayed green.
So the worker case reads KEY_ERROR off the worker's own Result, before anything downstream
can repair it. The two save cases have no such second line -- both write _state.value
directly -- so the state is the right thing to assert there, and both also assert that
`pending` still travels: a fallback that dropped the handle would leave the file
unreachable from the very screen that just said the save failed.
Held in one class against the ticket's suggestion of three. They are one rule at three
layers, and the masking above has to be explained once rather than three times.
FailedSaveRetryTest already sets the precedent for both ViewModels in one file; this adds
one worker to that shape.
FORCE_SOFTWARE in the worker fixture so the failure comes straight out of runFFmpeg. AUTO
would enter runMedia3OrFallBack, whose catch runs the job a second time in software: the
same exception arrives, but by a path this is not about and which HardwareFallbackTest owns.
Mutations, all run and restored -- each site to .orEmpty(), never to a different constant,
which would only prove the test reads a constant:
ConversionWorker:316 1 of 587 red (this file)
ConversionViewModel:631 red
JoinViewModel:416 red
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
JMR-devandClaude Opus 5