runMedia3OrFallBack was eleven lines at 0% and isCancellation had never been called by any
JVM test -- ci=0, not merely a missed branch. The seam to reach it has existed the whole
time: ConversionDependencies.hardware, which no unit test had ever set. What kept the path
cold is that every worker test uses EnginePreference.FORCE_SOFTWARE, which never enters
the function, and the probe defaults to UNPARSEABLE, which PERMISSIVE.canDecode refuses --
so even AUTO would have routed straight to FFmpeg for a reason no assertion mentioned.
Both are now stated in setUp rather than inherited.
Four behaviours, each with the mutation that proves it:
hardware failure falls back to software delete the fallback call
... on a *clean* staging file delete staged.delete() before it
cancellation is rethrown, not fallen back delete `if (isCancellation(e)) throw e`
engine.close() runs either way empty the finally block
the display-name fallback (#169) change "input" to anything else
All five confirmed red, then restored.
The cancellation one is the reason this ticket was first in the group. runMedia3OrFallBack
catches Throwable, so without that re-throw a user cancelling a hardware transcode has the
app quietly start a *second* conversion in software -- the one thing cancelling is for.
ForcedFailureTest covers the failure half on a device and does not cover this half at all.
The clean-staging assertion is made where it is observable rather than by reading the
file: the software fake records whether the output existed when it was entered, so a
missing delete shows up as FFmpeg finding a half-written hardware output at the path it is
about to write.
556 -> 560 JVM tests, 0 failures. No production code changed.
ConversionWorker: 22 -> 9 missed lines, 14 -> 7 missed branches.
Line 2090/2348 -> 2103/2348; branch 1022/1340 -> 1029/1340.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>