chromium/third_party/blink/web_tests/wpt_internal/README.md

This directory is the Chromium-internal (\*) counterpart of `external/wpt`. All
WPT features (except some `wpt lint` rules) are enabled in this directory,
including wptserve. This directory is mapped to `wpt_internal/` on wptserve.

When including additional scripts from tests within this folder, the "root"
folder is `external/wpt` and paths should be relative to that. (e.g.,
`/resources/testharness.js` will reference `external/wpt/resources/testharness.js`).

(\*) "Internal" in the sense that tests are not synchronized with the [WPT
upstream](https://github.com/web-platform-tests/wpt) or other browser vendors.

This directory is primarily intended for testing non-web-exposed and/or
Blink-specific behaviours (Blink internal testing APIs are allowed) with WPT
goodness (wptserve, testharness, reftest, etc.). Please try to use `external/wpt`
whenever possible.

Note: tests have to go into subdirectories. Files in the root level of
`wpt_internal/` are not recognized as tests.