[HugoXK]

Fixes #1839

Owner: Dev2
Written-by: Dev-2
Reviewer: Reviewer
Claim-Id: a497345b7dd544c0b87a56a96d6217cc
Base: f245520
Tip SHA: 3b8d239
Tree: 25d3f899aec104f2a0f95a83568bde15a1ea6a20
Diff: 2 files, +38/−18

What changed

core/test/room-invite-preview.test.js drew the card — the render itself calls Date.now()
inside inviteCountdown — and then compared the deadline line against
inviteCountdownAt(preview.expiresAt, 0, Date.now()). Two independent clock reads: when a
second boundary falls between them the expectation is one second ahead of the drawn line, so
the case flakes. Seen once on f245520c in a full verify as 37958984:53 left to join against
:52; 60 single-file runs never reproduced it.

The case now reads the clock once and freezes it for the whole assertion — one instant drives
both the render and the expectation:

const realNow = Date.now
const frozen = realNow()
Date.now = () => frozen
try {
  const tree = RoomInvitePreview({ h, preview, onJoin() {}, onClear() {} })
  // …
  assert.equal(tree.children[3].children.join(''), inviteCountdownAt(preview.expiresAt, 0, frozen))
  // …
} finally {
  Date.now = realNow
}

No tolerance: the comparison is still exact text at one instant, so a genuine off-by-one inside
inviteCountdown still fails. No production change — core/src/client/room-invite-preview.js
is untouched and no clock parameter is added.

patches/ds-bot/files/test/room-invite-preview.test.js is the whole-file mirror, byte-identical
(sha1 c172eb851f7b45b07b843fd90b61b04cf5569b35 both sides). No .patch regeneration and no
topics.json change: this file is a whole-file mirror, not an edited upstream file.

Red first

Probe 1 — the current assertion is clock-sensitive. Clock advanced 1000 ms per read, current
case unchanged, restored in finally:

not ok 1 - \#876: the card names the room, its lead, its people and the deadline
  + '37958977:48 left to join'
  - '37958977:47 left to join'
# tests 5
# pass 4
# fail 1

Probe 2 — the fixed assertion is immune and not vacuous:

• frozen clock, file as committed: # tests 5 / # pass 5 / # fail 0.
• the same case with the expectation mutated by one second (frozen - 1000) must fail, and does:

not ok 1 - \#876: the card names the room, its lead, its people and the deadline
  expected: '37958977:46 left to join'
  actual: '37958977:45 left to join'
# tests 5
# pass 4
# fail 1

200 consecutive runs of the file at this tip: runs=200 failures=0 elapsed=36s.

Verification at the tip

Ran: at 3b8d23941035fd80dc757f8982519480c40d0a30 (tree 25d3f899), git status --porcelain
empty before and after:

$ TZ=UTC ARCH_DOCS_BASE=f245520cbbcb7de1931a91c07c675e20dbe9fc79 npm run verify
$ node scripts/ds-bot-patches.mjs check

• core: 2203/2203 pass, including test/room-invite-preview.test.js 5/5
• plugins social 541/541, tree 127/127, timeline 135/135, workflow 294/294
• .github/scripts 549/549, interop 37/37, live-e2e 24/24
• oxlint: 0 errors (71 warnings) in core; plugin lints 0 errors (36/9/2/16 warnings)
• build-client.mjs --check: clean
• arch-docs: OK (2 changed file(s)), ARCH_DOCS_BASE=f245520cbbcb7de1931a91c07c675e20dbe9fc79
• patch chain:

ok   ds-bot/ = Fei2411/DeepSeek-Bot@2b10c70 (tree 5834c00, v0.1.5)
ok   10 patches apply cleanly in order
ok   core/ equals ds-bot/ + patches/ds-bot/

One honest note on the run: the first full verify at this tip went red on an unrelated file —
core/test/room-external.test.js:79, "timed out waiting for the child" after 4.1 s — not on
anything this change touches; that file alone passed 3/3 afterwards and the rerun above is
green. Recorded rather than hidden.

Not run: the smoke bench (no index.js/src/host/ change), the CI package job (pack check,
typecheck, actionlint) and the merge-queue rebuild.

Checkpoint

{
  "pr": 1840,
  "claim": "Dev2",
  "issue": 1839,
  "summary": "The room-invite preview case drew the card, whose render reads Date.now() inside inviteCountdown, then compared the line against a second Date.now() read, so a second boundary put the expectation one second ahead. The case now reads the clock once, freezes it for the whole assertion and restores it in finally; the comparison stays exact text with no tolerance and no production file changes. An advancing-clock probe fails on the old assertion and passes on the new one, a one-second mutation still fails, 200 runs stayed clean. The whole-file mirror under patches/ds-bot/files is byte-identical.",
  "files": [
    "core/test/room-invite-preview.test.js",
    "patches/ds-bot/files/test/room-invite-preview.test.js"
  ],
  "checks": {
    "ran": "TZ=UTC ARCH_DOCS_BASE=f245520c npm run verify; node scripts/ds-bot-patches.mjs check; 200x node --test test/room-invite-preview.test.js",
    "result": "green",
    "at": "3b8d23941035fd80dc757f8982519480c40d0a30"
  },
  "next": "none — ready for review"
}