* perf(worktree): batch remote conflict probes, re-arm the prepared checkout
A repo with many remotes paid one `git show-ref --verify` subprocess per
remote on every branch-conflict check during create. Ask one
`git cat-file --batch-check` over stdin instead; it reports a missing ref
as data rather than a failed exit, so a batch stays as decidable as the
per-ref probe. Hosts that cannot feed stdin, and undecided batches, still
fall back to the per-ref path.
The prepared checkout was single-use, so the second create in a row paid
the full cold `git worktree add`. Re-arm it in the background after one is
consumed; the existing TTL and preparation limit still bound it.
The create timing recorder existed but its phases were never emitted and
did not cover preflight, leaving a multi-second gap in the trace with no
attribution. Add `resolve_name`/`prepare_push_target` phases and record the
breakdown, plus the unattributed remainder, on the create span.
* fix(worktree): format the conflicting review number eagerly for the create error
* perf(worktree): re-arm a prepared checkout only for a burst of creates
Re-arming after every consumed preparation spends a full checkout and
~200MB of disk on a user who created one worktree and stopped, then pays
an unexplained delete when the TTL expires five minutes later. Track when
each preparation key was last consumed and only replace it when a second
create lands inside the burst window, so the warm second create is still
free and an isolated create costs nothing.
* fix(worktree): address review findings on the create-path batching
Three findings from PR review:
The `batched.found` fallback in the remote-conflict probe was unreachable
— a present ref is decisive, so `found` never survives with `unknown`
set, and the guard above already returns that case.
`rearmPreparation` checked for an existing preparation before recording
the consume, so a prefetch that re-armed the key while create finalized
swallowed the timestamp and made the next create look isolated when it
was really mid-burst.
Create runs some phases concurrently, so summing phase durations
double-counted overlap and understated `unattributed_ms` — the one
number that matters when a create is slow for no visible reason. Measure
the union of the phase intervals instead.
* refactor(worktree): move stale-preparation cleanup into its own module
The preparation module crossed the 300-line budget. Crash recovery is a
separate concern from the pool itself — it discards preparations another
process left registered, single-flighted per repo and runtime so a burst
of arming calls shares one worktree listing.
* test(worktree): make the re-arm test able to fail
The burst test armed a preparation manually after the second consume, so
the third checkout appeared whether or not the re-arm produced it — the
assertion passed with re-arming disabled. Drop that arming call so the
third checkout can only come from the re-arm, and assert the consume
results rather than discarding them.
Neil
e89321192a