wp-includes/rest-api/class-wp-rest-response.php:181Sets the route (regex for path) that caused the response.
$routestring public function set_matched_route( $route ) { $this->matched_route = $route; }Introduced in 4.4.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/rest-api/class-wp-rest-response.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.