GitHub issue #558: clicking Auto-Fill / Fix Selected on the Album
Completeness findings page returned a flat "Could not determine album
folder from existing tracks" error with no diagnostic. Reporter is on
Navidrome on Docker — the path resolver in
`core/library/path_resolver.py` couldn't find any of the album's tracks
on disk because Navidrome's Subsonic API doesn't expose filesystem
library paths the way Plex's API does (probed in #476). Default
settings → `library.music_paths` empty → no base directories to probe →
silent None. User had no signal about what to configure.
Not a regression of #476 — that fix targeted Plex auto-discovery and
worked correctly for it. Navidrome was never covered because the
protocol gives the resolver nothing to probe.
Fix scoped to the diagnostic surface, not auto-magic discovery:
- Added `resolve_library_file_path_with_diagnostic` returning
`(resolved, ResolveAttempt)`. ResolveAttempt records what the resolver
tried — `raw_path_existed`, `base_dirs_tried`, `had_config_manager`,
`had_plex_client`. Pure data, no rendering opinions.
- Legacy `resolve_library_file_path` becomes a thin wrapper that
drops the attempt; every existing call site is unchanged.
- `RepairWorker._fix_incomplete_album` now uses the diagnostic helper
and renders a multi-part error via `_build_unresolvable_album_folder_error`:
names the active media server, shows one sample DB-recorded path,
lists every base directory the resolver actually probed, and points
the user at Settings → Library → Music Paths as the actionable fix.
- Distinguishes empty-base-dirs vs tried-and-failed cases so the user
knows whether to add a mount or fix the existing one.
- No auto-probing of common Docker conventions (`/music`, `/media`, etc).
Speculative — could resolve to wrong dirs on the suffix-walk if a
conventional path happens to contain a partial collision. User stays
in control.
12 new tests:
- 7 in `tests/library/test_path_resolver.py`: tuple-shape contract,
raw-path-existed short-circuit, base-dirs listed even on walk
failure, had-flags reflect caller inputs, no-base-dirs returns
None with empty attempt, legacy `resolve_library_file_path`
delegates correctly across happy / suffix-walk / failure paths.
- 8 in `tests/test_repair_worker_unresolvable_folder_error.py`:
active server name in error, sample DB path verbatim, base dirs
listed, empty-base-dirs phrased differently, Settings hint always
present, defensive against None attempt / missing sample / missing
config_manager.
Full pytest sweep: 2774 passed.