Adversarial review of PR #61 found one real coverage loss, and it is the
defect class that PR's own body names: an assertion that survives the deletion
of the thing it was about. `shell.spec.js` lost "a socket that opened and then
dropped reads as disconnected, and stays that way" and both MutationObserver
negative assertions. Reverting PR #21's routing half in `web/app.js` — the
socket `error` and `close` arms calling `setShell` instead of `fail` — left the
node suite 26/26 and Playwright 13/13 green.
`shell.test.js` cannot cover it, and why is the whole boundary argument:
"a loud failure DISARMS the watchdog" tests `createShell` in isolation and
cannot see whether `app.js` ROUTES the close event through `fail()`. That
routing is the half gotcha 48 says keeps getting lost; this was the third time,
after two earlier mis-confirmations that simulated the `opened` flag and not
the routing.
Both tests are back under their original names, so the two `####` headings in
context/test-evidence/clients.md name live tests again. They cost ~75ms each
rather than ~9s, because `page.clock` fakes the PAGE's timers: the page, the
socket, the listeners and the `setTimeout` call are all real and only the
passage of time is simulated. That is not a weakening, and the injections are
the proof in both directions — if `runFor` did not advance the page's timers, a
broken routing could not surface the watchdog's message and they would pass:
- both arms reverted to `setShell` -> "…and stays that way" fails
- close arm only -> "…and stays that way" fails
- close arm drops the `opened` flag -> "…the watchdog stays out of it" fails
Three injections, three outcomes, none of them the unit test.
The helper guards its own premise, because it turned out not to: `runFor`
without `clock.install()` does nothing AND throws nothing, so a test that
forgot the install asserted "the watchdog never spoke" against a watchdog that
never ran — 6/6 green. `outlastTheWatchdog` now requires the page's own
`Date.now()` to have moved, and that omission fails by name.
Also: `render_surface.test.js` matched `model.<field>` over source INCLUDING
comments, so un-painting a field and mentioning it in a comment passed —
demonstrated against the pre-fix version, then fixed and re-demonstrated.
And the PR's speed claim is corrected where it is documented. The eleven
deleted per-widget tests cost 3.3s between them against 3.4s for the three
contract tests replacing them: they were free. Essentially all of 36.9s -> 15.5s
was two real-timer waits, one of them this guard. The wait was the cost, not
the test.
Filed, not fixed: improvise-igxp (the help overlay's rows are asserted as
present, never as content — inherited verbatim from the test contract.spec.js
replaced) and improvise-4ktt (the js job's bundle-freedom is a shell-glob
convention, not a gate). The `####`-vs-`###` blind spot in --check-evidence,
which is why the dangling heading survived the gate, is a comment on
improvise-r0qa.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Edward Langley
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