CNA-VGAP-006: Media paths without tests: the natural song end on SDL3_mixer, the failed visualization install, MediaLibrary accessors after Dispose and SavePicture's IOException

CNA snapshot 009d40f5  ·  Known Issues › Verification gaps  ·  source links pinned to 009d40f5

The song-ended callback path on the default SDL3 audio, the visualization branch where no tap can be installed, MediaLibrary disposal semantics and SavePicture's write-failure exception are implemented but untested.

Identifier

CNA-VGAP-006

Category

Verification gap

Subsystem

Audio & media

Status

Open

Verified against

CNA 009d40f5 (009d40f5dd085c4e674d3479675fac84b12b3e0a)

Evidence basis

Source-verified: read at TARGET, not executed

Tests touching this area

Yes: see Current tests

Affected contract

MediaPlayer::Update end-of-song handling, MediaPlayer::setIsVisualizationEnabledProperty, MediaLibrary::Dispose and MediaLibrary::SavePicture

Expected behaviour

Each behaviour a game relies on has at least one test in the default configuration (SDL3 audio).

Actual behaviour at TARGET

• Natural song end on SDL3_mixer. OnMusicTrackStopped sets the ended flag from the audio thread and Update advances, stops or repeats. The only test that lets a song finish, MediaPlayerTest.Mp3AndFlacSongsPlayThroughCnasOwnMixerToTheirEnd, is compiled only for ALSA audio.
• Visualization without a tap. The comment on VisualizationEnabledStateStaysConsistentWithGetVisualizationData states that the suite always has a dummy SDL device, so the no-mixer and failed-install branches of setIsVisualizationEnabledProperty are correct by construction only.
• MediaLibrary::Dispose. It only sets isDisposed_; the collection accessors do not consult it. MediaLibraryTestFixture.DisposeMarksLibraryDisposed checks the flag and nothing else; the pure-C CApi_MediaLibrarySmoke additionally pins a repeated dispose and that cna_media_library_get_songs still succeeds on a disposed library, but no test pins the other accessors.
• SavePicture failure. MediaLibrary::SavePicture throws System::IO::IOException when the store returns no path. The store's name-sanitising and empty-root cases are tested at store level (SavedPictureStoreTests.cpp), but no test drives the public method into the exception.

Source locations

• modules/media/src/Xna/MediaPlayer.cpp — OnMusicTrackStopped, Update, setIsVisualizationEnabledProperty
• modules/media/tests/Microsoft/Xna/Framework/Media/MediaPlayerTests.cpp — Mp3AndFlacSongsPlayThroughCnasOwnMixerToTheirEnd (ALSA only); the visualization comments
• modules/media/src/Xna/MediaLibrary.cpp — MediaLibrary::Dispose; MediaLibrary::SavePicture
• modules/media/tests/Microsoft/Xna/Framework/Media/MediaLibraryTests.cpp — DisposeMarksLibraryDisposed; the SavePicture cases
• modules/media/tests/CNA/Internal/Media/SavedPictureStoreTests.cpp — store-level sanitising and empty-root cases

Evidence

Checked by reading the test sources at 009d40f5; no test was run. Nothing in these paths is known to be wrong; the gap is evidence. MediaLibrary::Dispose not guarding its accessors is recorded as observed, not judged against XNA here.

Independently observed as a separate finding (merged): Every media test runs with a dummy SDL audio device, so GetMixer always succeeds and the no-mixer and failed-install branches of setIsVisualizationEnabledProperty are correct only by construction.

Independent re-verification: Checked by reading the test sources at 009d40f5; no test was run. Nothing in these paths is known to be wrong; the gap is evidence. The pure-C smoke tests under modules/c-api/tests/pure_c are registered with ctest (CApi_MediaLibrarySmoke, CApi_MediaPlayerSmoke) and were not counted by the entry; they do not let a song finish or drive SavePicture to an IOException. MediaLibrary::Dispose not guarding its accessors is recorded as observed, not judged against XNA here.

Focused reproduction

No focused reproduction is known. Nothing has been invented here; the evidence above is what exists.

Current tests

As listed above: the ALSA-only song-end case, the visualization round-trip cases with a working device, the dispose-flag case and the successful and null-stream SavePicture cases.

Regression test

A short-fixture song played with SDL_AUDIODRIVER=dummy until Update reports Stopped (and the next song with repeat on); a visualization test with a forced mixer-creation failure (the mixer's test override hooks allow it); a MediaLibrary test that pins what accessors do after Dispose; a SavePicture test against an unwritable pictures root expecting IOException.

Blast radius

Games that rely on songs ending (playlists, repeat) on the default SDL3 audio, on visualization data on headless or audio-less machines, on MediaLibrary disposal, or on SavePicture error handling.

Workaround

No workaround is known.