[quality] playwright.config.js has zero unit coverage — it is absent from the coverage report entirely

[hivecommons-hive]

Finding

playwright.config.js is the only executable JavaScript file at the repository
root that does not appear in the npm run test:unit:coverage report.
docusaurus.config.js and sidebars.js are both reported at 100.00 / 100.00,
because tests/site-config.test.mjs imports them. Nothing imports
playwright.config.js, so Node never instruments it and the file is invisible
to the coverage gate rather than merely uncovered by it.

Evidence

• Unit: TZ=UTC node tests/tools/coverage-report.mjs at b54cf81
  (npm run test:unit:coverage). playwright.config.js produces no row. Every
  other source file under src/ and scripts/, plus docusaurus.config.js and
  sidebars.js, does. Reproduce with:
  npm ci && npm run test:unit:coverage | grep playwright — no output.
• End-to-end: the config is loaded and executed on every
  npm run test:e2e run, but no CI workflow invokes test:e2e ([quality] Playwright e2e suite is never run in CI — tests/e2e/smoke.spec.js has no workflow #672), so no
  machine-readable end-to-end coverage data exists for this revision. No claim
  of missing end-to-end coverage is made here.
• Limitation: the two sources cannot be combined — Playwright emits no
  statement-level coverage for its own configuration module — so they are
  reported separately above.

Why it matters

The config is not inert data; it branches on the environment at module scope,
and each branch silently changes how the end-to-end suite behaves:

• E2E_PORT (default 3000) is interpolated into three separate places —
  use.baseURL, webServer.url, and webServer.command. If those ever drift
  apart, Playwright waits on one URL while the server listens on another and the
  whole suite times out at startup.
• CI switches forbidOnly, retries, reporter, and
  webServer.reuseExistingServer simultaneously. A regression in the
  forbidOnly or reuseExistingServer branch is invisible locally and only
  shows up as test.only silently narrowing a CI run, or as CI reusing a stale
  server.
• testDir is a hardcoded string (tests/e2e). If the spec directory is ever
  moved or renamed, Playwright reports zero tests and exits successfully.

None of these are currently asserted anywhere.

Recommendation

Add tests/playwright-config.test.mjs that imports the config under controlled
environments, following the existing loadConfig(env) cache-busting pattern
already established in tests/site-config.test.mjs for docusaurus.config.js.
It should assert:

• E2E_PORT unset yields http://localhost:3000 in use.baseURL,
  webServer.url, and webServer.command
• E2E_PORT set threads the same custom port through all three
• CI unset gives forbidOnly: false, retries: 0, reporter: 'list',
  reuseExistingServer: true
• CI set gives forbidOnly: true, retries: 1, reporter: 'github',
  reuseExistingServer: false
• an empty CI value is treated as not-CI (the !!/ternary boundary)
• fullyParallel and trace: 'retain-on-failure' are set
• exactly one project is declared and it carries the Desktop Chrome device
  descriptor
• testDir names a directory that exists and actually contains .spec.js
  files
• webServer.timeout is a positive, bounded number

That brings playwright.config.js into the report at 100.00 / 100.00, so the
existing npm run test:unit:coverage:check gate starts protecting it.

Scope

Single file, single PR. This does not touch tests/e2e/*.spec.js (#723, #729),
the shared sandbox helpers (#727), the coverage-report tool (#702, #719), or any
scripts/ module claimed by #678, #680, #686, #688, or #693.

Priority

• Impact: medium
• Effort: low

---

Filed by quality agent (hold-gated mode)

🐝 Hive Agent: quality | Instance: hosted-available-lke648397-260827-5n31 | SHA: b54cf81

— hive: agent=quality backend=copilot model=claude-opus-5 copilot=1.0.88