Currently, tests that need a guaranteed-nonexistent hostname are meant to use the nonexistent subdomain under the WPT-controlled domains (typically, nonexistent.web-platform.test).
However, RFC 6761 §6.4 reserves the .invalid TLD specifically for this purpose — names under .invalid SHOULD always return a negative response.
There is already some usage of .invalid in tests today, e.g.:
But: there's no explicit policy permitting it, and the lint rules don't forbid it.
Currently, tests that need a guaranteed-nonexistent hostname are meant to use the
nonexistentsubdomain under the WPT-controlled domains (typically,nonexistent.web-platform.test).However, RFC 6761 §6.4 reserves the
.invalidTLD specifically for this purpose — names under.invalidSHOULD always return a negative response.There is already some usage of
.invalidin tests today, e.g.:websockets/constructor/008.html#L11webtransport/stats.https.any.js#L50url/resources/setters_tests.json#L1146But: there's no explicit policy permitting it, and the lint rules don't forbid it.