The rebase onto main was textually clean and behaviourally broken, and this
PR's own guard is what caught it.
This branch removed test/release.test.ts's `mkdtempSync`/`tmpdir` imports when
it converted that file's call sites to `tmp()`. While it was open, #133's
changelog-monotonic work landed on main and added THREE new
`mkdtempSync(join(tmpdir(), ...))` sites to the same file. The two changes
never touch the same line, so git merged them without a word — leaving call
sites whose imports this branch had deleted. 20 tests died on
`ReferenceError: mkdtempSync is not defined`.
Converted all three to `tmp()`, which is what the file already imports and
what every other test file under test/ uses.
Worth noting which test failed and why it matters: test/tmp-guard.test.ts,
this PR's own class check, reported `offenders: ["release.test.ts"]`. It was
written to stop exactly this — a new raw allocation drifting in — and it did
so on a real regression rather than a synthetic one, before the fix existed.
That is the guard earning its place on its first genuine encounter.
The suite allocated temp dirs at 68 sites across 21 files and removed none,
accumulating ~6700 directories and 189MB per machine-day, some holding age
keys. All 68 now go through a single `tmp()` helper allocating inside a
per-run root that vitest's globalSetup teardown removes wholesale, and a
class-guard test fails if `mkdtempSync` appears under test/ outside the
helpers.
The per-worker `process.once("exit")` reaper that suggests itself here does
not work under vitest and fails silently: the pool recycles workers by
killing them, so exit handlers registered in a test file never run. Measured
— a probe test writing from an exit hook produced no file, and a full run
with per-worker hooks still left 750 directories. globalSetup's teardown runs
in the main process, after every worker, and vitest awaits it.
Separately, and contrary to #117's framing that "cast itself does not leak":
resolveCheckout() mkdtemps an `infra-checkout-` dir, clones the infra repo
into it, and never removes it, so every `cast apply`/`diff`/`capture` without
--path leaked a full clone. The box that reported #117 was holding 602 such
directories, 73MB of real .git trees, from the same day. The leak fires on
the failure path too, since the dir is created before the clone runs.
Ephemeral checkouts are now reaped on process exit — the lifetime that fits,
since callers read the tree after resolveCheckout returns; a --path checkout
is the operator's own tree and is never registered.
Empirical: /tmp/cast-* + /tmp/infra-* count is 0 before and 0 after a full
`npm test`, against 750 with the exit-hook design. 626 tests green.
Refs #117
