Source

File: wp-includes/rest-api/endpoints/class-wp-rest-controller.php

public function register_routes() {
		_doing_it_wrong(
			'WP_REST_Controller::register_routes',
			/* translators: %s: register_routes() */
			sprintf( __( "Method '%s' must be overridden." ), __METHOD__ ),
			'4.7'
		);
	}