Caught while live-testing the #524 fix with kendrick lamar
mr morale & the big steppers (3 discs). User dropped discs 1+2
loose in staging root + disc 3 in its own folder, every file
perfectly tagged with disc_number/track_number/title — only 9
tracks ended up in the library, the rest got integrity-rejected
and quarantined.
Two related bugs in `AutoImportWorker._match_tracks`:
1. **Quality dedup keyed on track_number alone.** The dedup loop
kept `seen_track_nums[track_number] = file` and dropped any later
file with the same number, treating it as a quality duplicate.
On a multi-disc release where every disc has tracks 1..N, that
collapses the album to one disc's worth of files BEFORE the
matcher runs. User's 18 loose disc-1+disc-2 files reduced to 9
before any title/disc info was even consulted.
2. **Match scoring ignored disc_number.** The 30% track-number bonus
fired whenever `ft[track_number] == track_num` regardless of disc.
File with tag (disc=2, track=6, "Auntie Diaries", 281s) got the
full bonus matching API track (disc=1, track=6, "Rich Interlude",
103s) — wrong file → wrong destination → integrity check correctly
rejected and quarantined the file. Same for tracks 7, 8, 9.
Fix:
- Dedup keys on `(disc_number, track_number)` tuples — multi-disc
files with parallel numbering all survive.
- Match scoring's 30% bonus only when BOTH disc AND track agree.
Cross-disc same-track-number collisions get a small 5% consolation
bonus so title similarity has to carry the match (covers cases
where tag disc info is missing or wrong).
- API track disc_number read from `disc_number` (Spotify) /
`disk_number` (Deezer) / `discNumber` (iTunes) defaulting to 1.
4 new pinning tests in `tests/imports/test_auto_import_multi_disc_matching.py`:
- 18-file 2-disc regression case (dedup preserves all)
- (disc=2, track=6) file matches API (disc=2, track=6) track, not
the disc-1 same-numbered track
- Single-disc albums still match normally (no regression)
- Quality dedup within a single (disc, track) position still picks
higher-quality format (.flac over .mp3)
Verification:
- 2268 full pytest suite passes (+4 new), 1 skipped, 0 failed
- Ruff clean
Same branch as the #524 fix because both surfaced from the same
import session — easier reviewer context if they ship together.
c03edc3cb4