skill_publication_identity_linux_test.go pinned the remote line's
Statx/birth-time identity design (skillPathStatx seam); the merged head
proves ownership with dev:ino plus the fingerprint backstop instead, so
the test no longer compiles on Linux. Caught by CI's Linux lint job,
which builds what macOS-local vet skips behind the linux build tag.
Reconciles the two parallel evolutions of PR #996 with this session's
publication design as authoritative:
- internal/upgrade, internal/app: ours — mkdir-claim identity witness
(dev:ino on POSIX, volume file ID on Windows), three-state ownership,
ErrSkillPathPublicationUncertain, copy-fallback short-circuits. Drops
the remote line's xattr publication-mark design and its six follow-up
fixes (retract contracts, Statx token); skill_publication_mark_*.go
removed accordingly.
- scripts/, build/npm/, test/scripts/, docs/rfc: theirs — same replayed
install hardening plus main's evolution and the npm no-clobber child
moves; no xattr dependency, consistent with the claim model.
- .changes: their npm/Shell/PowerShell narrative with the Go-design
sentences rewritten for the uncertain-publication contract.
Verified: go build, go vet (tests compiled), gofmt, and package tests
for internal/upgrade, internal/app, test/scripts all green on this tree.
The mkdir->rename->remove->rename directory fallback had a TOCTOU window
between the second remove and the second rename: a concurrent writer
creating an entry at the destination was silently clobbered. The fallback
now claims the destination once with mkdir and never unlinks it: the
fast-path rename publishes over the claim (Linux), and platforms that
refuse directory renames (macOS, Windows) move the staged children into
the claim through atomic no-clobber primitives (mkdir/os.Link/os.Symlink),
consuming the emptied source shell on success.
renameSkillPathNoReplace now returns the mkdir-claim identity captured by
the child-move path. PublishSkillPathNoReplace uses it as a three-state
ownership witness: the atomic/fast paths keep the staged-inode proof, the
child-move path proves dest is still the mkdir claim, and a mismatch
reports the new ErrSkillPathPublicationUncertain sentinel with the
destination retained. The witness is real on POSIX now: darwin and linux
report the dev:ino file identity instead of the empty no-op.
Upstream consumers honor the sentinel: the mono/multi upgrade copy
fallbacks no longer retry over an uncertain destination (the retry would
displace the concurrent writer's object), and skill setup reports the
retained destination instead of claiming a rollback.
Rewrites the fallback tests that pinned the removed remove-and-retry flow
and adds regression coverage: concurrent claim entries abort with the
destination retained, wholesale replacement after child-move reports the
uncertain sentinel, staged-set transactions pass the sentinel through,
and both copy fallbacks short-circuit (ablation-verified).
john