Review was right, and I had assumed the handle type rather than checking it.
Probed both under happy-dom:
setTimeout -> typeof "object", constructor Timeout
requestAnimationFrame -> typeof "object", constructor Immediate
So `typeof id === "number"` in the clearTimeout wrapper never matched, and an
explicitly-cleared timer was never untracked. Both `Set<number>` annotations and
`const id: number` were fictions TypeScript could not catch, since the DOM lib
DECLARES number while happy-dom RETURNS an object.
The effect was benign — the teardown sweep re-clears them and clearTimeout is
idempotent — but the sharper problem is that the test asserting this passed for
the wrong reason. "clearTimeout doesn't throw" holds whether or not tracking
works, so it proved nothing and hid the broken guard.
Hold handles as `unknown`, route cancellation through two small helpers that
carry the one justified cast each, and drop the numeric guards. The test now
asserts the net's own bookkeeping through an exported pendingTimerCount(), and
is mutation-checked: restoring the numeric guard fails it (1 failed | 6 passed).
That is the second test in this PR that passed without proving its claim. Both
had the same tell — the assertion would have held with the feature removed.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HDdo1rNRVQnVRRdsqSrvG3
Signed-off-by: cliffhall <cliff@futurescale.com>
Review found the net still had the exact hole it was written to close.
The afterEach is synchronous, so a queued rAF callback cannot run until it
returns — at which point it registers a fresh setTimeout AFTER the sweep has
already drained. On a file's last test that timer survives environment
teardown. That is the rAF race described in the previous commit message, left
open by the fix for it.
Track animation frames too, and cancel them BEFORE sweeping timers. Order is
the fix: JS is single-threaded and nothing between the two loops yields, so no
frame callback can run in between. Mutation-checked — without the cancel pass
the new ordering test fails (1 failed | 6 passed); with it, 7 pass.
Also from review:
- renderWithMantine.tsx still documented the disproven env="test" behavior. It
is the file contributors are told to use, so leaving it would have preserved
the wrong belief exactly where it does most damage. That was the third copy of
this claim in the repo; all three now corrected.
- Dropped an unjustified `as unknown as` in the test helper, which broke the
repo's own double-cast rule. Inference keeps the handle type clearTimeout
accepts.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HDdo1rNRVQnVRRdsqSrvG3
Signed-off-by: cliffhall <cliff@futurescale.com>
A window.setTimeout that outlives its test file fires after happy-dom disposes
that file's window; React's dispatchSetState then throws an uncaught
ReferenceError: window is not defined. Vitest attributes it to whichever file
was running, so a single leak fails the ENTIRE run with every test passing —
landing on an innocent file under a step named "Enforce per-file coverage gate."
Seen twice in CI, both on docs-only branches.
Not a Mantine bug, and not a badly-written test. Both hooks do clear on unmount
(useTransition's clearAllTimeouts, useLockScroll's effect cleanup). It is a rAF
race: clearAllTimeouts cancels the *pending* rAF, but the transition schedules
rAF -> rAF -> setTimeout, so if the inner callback is already in flight when the
unmount lands, cancelAnimationFrame is a no-op and that callback then schedules
a timer after cleanup has run. Nothing owns it. Needs a loaded machine, which is
why it only ever appeared in CI.
Track every timer and clear whatever is still outstanding after cleanup(). The
ordering is load-bearing: legitimate unmount cleanups get their turn first, so
only true leaks are dropped. Fake timers pass through untracked, which is
correct — a fake timer cannot outlive the environment.
Also corrects the claim, in AGENTS.md and in setup.ts's own comment, that
env="test" prevents this. It does not: env is read only by Transition.mjs at its
render branch, while useTransition runs before that check (hooks cannot be
conditional) and still schedules real timers. Measured — opening a <Modal>
through renderWithMantine schedules three 200ms timers. Believing that guarantee
is why this went unexamined.
The regression test is mutation-verified: with the net disabled it fails, with
it restored it passes. It deliberately does not assert that Mantine schedules no
timers — it does, and that is normal; the contract is that none survive.
Closes#1984
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HDdo1rNRVQnVRRdsqSrvG3
Signed-off-by: cliffhall <cliff@futurescale.com>
