The Playwright suite had no linter and no formatter — only tsc. Add flat-config ESLint
(typescript-eslint, type-aware) and Prettier (2-space, matching the suite's style).
Rules keep the ones that catch real TEST bugs and drop the noise:
- no-floating-promises KEPT — an un-awaited request/assertion can let a test end before it runs,
passing vacuously. It caught one: the SSE reader loop in sse-listener is now explicitly `void`.
- no-unused-vars KEPT — caught three dead bindings (an unused adminToken fixture arg, an unused
`api` arg, an unused JPEG_MAGIC import), all removed.
- no-explicit-any OFF — all test code; `any` is the honest type for an untyped res.json() body or
a page.evaluate() return.
- no-empty-pattern OFF — Playwright's dependency-free fixtures are `async ({}, use) => {}`.
Refactor: `const BASE = process.env.E2E_FRONTEND_URL ?? '...'` was redeclared verbatim in 23
files — extracted to helpers/env.ts and imported, so a port/scheme change is one edit not a sweep.
Then `prettier --write`. Verified: eslint clean, tsc clean, prettier clean, desktop suite 210
passed / 1 skipped. (One mobile spec flaked once under retries:0 — a pre-existing cross-test
reflow-timing vector from the flakiness audit, not this change: the each-key edit is stable across
16 isolated runs and a clean full mobile re-run.)
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
