Sonarr and Lidarr each keep their own copy of the shared fixture, both with minimum_age and retention set to 1, so transposing those two fields stayed invisible in either tree. Radarr built its fixture from IndexerSettings::default(), leaving availability_delay, maximum_size, minimum_age and retention all 0: four mutually transposable fields, none of which could distinguish a threaded value from a hardcoded 0.
The no-op guard test seeded IndexerSettings::default() as its sentinel, which cannot show whether the guard held or the field was simply never written. It now seeds a distinct stale_indexer_settings(), mirroring the Readarr convention.
Verified by transposing minimum_age and retention in the Lidarr indexer settings UI, now caught by its snapshot, and by inverting the Radarr no-op guard, now caught by both GetAllIndexerSettings tests.
Dark-Alex-17
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