References — bi-13 Chromium Test Architecture & Web Platform Tests

Primary sources first. In-tree Chromium docs beat any external source, including these modules.

Chromium testing

Testing in Chromium — the index
Web tests (formerly layout tests) — how to run, rebaseline, and read expectations
Web test expectations — TestExpectations, flakiness, and [ Failure Pass ]
Unit tests / gtest

Web Platform Tests

web-platform-tests.org — the shared cross-browser conformance suite
WPT repository
wpt.fyi — per-browser results; the fastest way to see whether a behaviour is interoperable or a Chromium quirk
Running WPT in Chromium — the two-way export/import process

bi-03 — HTML parsing — html5lib-tests and html/syntax
bi-14 — Contributing — a WPT test is often the most reviewable first contribution
fe-33 — E2E testing (planned) — the application-level testing track

When a claim here proves stale, record it in PROGRESS.md section 7.