Addresses @egilewski's review: the parent-directory check still deleted
checkpoint history for the most common unmount layout.
Detaching storage removes the parent outright in some layouts
(`/Volumes/Ext/proj` on macOS, `/media/<user>/<label>/proj`), which the first
commit handles. But in the classic static layout — `/mnt/volume/proj`, an
fstab entry, a container bind-mount — unmounting removes the contents and
leaves the mount point behind as an empty directory. `parent.is_dir()` is then
true, the project is absent, and the startup sweep deletes its ref, index and
metadata: exactly the case this PR set out to protect.
Reproduced against the real predicate before this commit:
mount root vanished (macOS) -> False ok
empty surviving mount point -> True <-- history deleted
really deleted (siblings) -> True ok
An empty parent carries no information: it looks identical whether the volume
was detached or the project was deleted. So require the parent to actually say
something — it holds some other entry (we observed a populated directory that
does not contain the project), or it is itself a live mount point (the volume
is attached right now and demonstrably does not hold the project).
The cost is that a project deleted out of an otherwise-empty parent is no
longer reclaimed by the orphan rule. It is not leaked: the retention rule
reads `last_touch` rather than probing the filesystem and still collects it,
so reclamation is deferred, not lost. That is the right direction for a
predicate whose false positive destroys a user's restore points unattended.
`_dir_has_any_entry` stops at the first entry via `os.scandir` instead of
materializing a listing, since a project root can hold a large tree.
tests/tools/test_checkpoint_manager.py: `test_surviving_empty_mountpoint_
keeps_its_checkpoints` pins the reviewed case, and `test_empty_parent_project_
is_still_reclaimed_by_retention` pins the deferral above so the safety valve
cannot silently regress into a leak. Both fail on the previous commit. The
real-orphan control now seeds a sibling so it exercises a populated parent
rather than the ambiguous empty one. 80 passed in the checkpoint suite; the 2
remaining failures (`TestGitEnvIsolation`, `TestClearFunctions`) fail
identically on clean main.
Frowtek
1fc338a4ec