`newServiceFixture` stops auto-pick from starting a grab, because none
of its tests is about the download and a detached `go m.grab(...)`
racing `t.TempDir()`'s cleanup is how they fail. It did that with
`MaxSizeMB: 1` -- and the size gates read `Candidate.TotalSize`, which
real providers fill and the fake leaves at zero. Zero is under every
ceiling, so the guard never fired and the race it was written to
prevent kept happening, roughly one run in fifteen:
TempDir RemoveAll cleanup: unlinkat ... : directory not empty
The guard is a format the fake never produces. Thirty consecutive
whole-package runs, none.
`TestManualDownloadSatisfiesRequestOnSuccess` was relying on the guard
being broken -- it is the one test here that wants the download -- so
it now clears the preferences itself rather than depending on a bug.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MeQt5hgXg5YGoNZQ9ozG7L