Add phpcs rule to detect unused variables; Fix existing issues (WordPress#17300)

Author: jorgefilipecosta

composer.json

@@ -14,7 +14,8 @@
 		"dealerdirect/phpcodesniffer-composer-installer": "^0.5.0",
 		"squizlabs/php_codesniffer": "^3.4.2",
 		"phpcompatibility/php-compatibility": "^9.2.0",
-		"wp-coding-standards/wpcs": "^2.1.1"
+		"wp-coding-standards/wpcs": "^2.1.1",
+		"sirbrillig/phpcs-variable-analysis": "^2.7"
 	},
 	"require": {
 		"composer/installers": "~1.0"

composer.lock

@@ -110,6 +110,7 @@ function gutenberg_build_files_notice() {
  * @since 1.5.0
  */
 function gutenberg_pre_init() {
+	global $wp_version;
 	if ( defined( 'GUTENBERG_DEVELOPMENT_MODE' ) && GUTENBERG_DEVELOPMENT_MODE && ! file_exists( dirname( __FILE__ ) . '/build/blocks' ) ) {
 		add_action( 'admin_notices', 'gutenberg_build_files_notice' );
 		return;

gutenberg.php

@@ -71,10 +71,9 @@ public function register_routes() {
 	 *
 	 * @since 6.5.0
 	 *
-	 * @param WP_REST_Request $request Full details about the request.
 	 * @return WP_Error|bool True if the request has permission, WP_Error object otherwise.
 	 */
-	public function permissions_check( $request ) {
+	public function permissions_check() {
 		if ( ! current_user_can( 'install_plugins' ) || ! current_user_can( 'activate_plugins' ) ) {
 			return new WP_Error(
 				'rest_user_cannot_view',
@@ -221,8 +220,8 @@ public function get_items( $request ) {
 
 		include( ABSPATH . WPINC . '/version.php' );
 
-		$url      = 'http://api.wordpress.org/plugins/info/1.2/';
-		$url      = add_query_arg(
+		$url = 'http://api.wordpress.org/plugins/info/1.2/';
+		$url = add_query_arg(
 			array(
 				'action'              => 'query_plugins',
 				'request[block]'      => $search_string,
@@ -231,11 +230,12 @@ public function get_items( $request ) {
 			),
 			$url
 		);
-		$http_url = $url;
-		$ssl      = wp_http_supports( array( 'ssl' ) );
+		$ssl = wp_http_supports( array( 'ssl' ) );
 		if ( $ssl ) {
 			$url = set_url_scheme( $url, 'https' );
 		}
+
+		global $wp_version;
 		$http_args = array(
 			'timeout'    => 15,
 			'user-agent' => 'WordPress/' . $wp_version . '; ' . home_url( '/' ),

lib/class-wp-rest-block-directory-controller.php

@@ -52,12 +52,6 @@ public function register_routes() {
 			'validate_callback' => 'Experimental_WP_Widget_Blocks_Manager::is_valid_sidabar_id',
 		);
 
-		$content_argument = array(
-			'description' => __( 'Sidebar content.', 'gutenberg' ),
-			'type'        => 'string',
-			'required'    => true,
-		);
-
 		register_rest_route(
 			$this->namespace,
 			'/' . $this->rest_base . '/(?P<id>.+)',
@@ -141,6 +135,9 @@ public function get_item_schema() {
 	 *
 	 * @param WP_REST_Request $request Full details about the request.
 	 * @return WP_Error|bool True if the request has read access, WP_Error object otherwise.
+	 *
+	 * This function is overloading a function defined in WP_REST_Controller so it should have the same parameters.
+	 * phpcs:disable VariableAnalysis.CodeAnalysis.VariableAnalysis.UnusedVariable
 	 */
 	public function get_items_permissions_check( $request ) {
 		if ( ! current_user_can( 'edit_theme_options' ) ) {
@@ -152,6 +149,7 @@ public function get_items_permissions_check( $request ) {
 
 		return true;
 	}
+	/* phpcs:enable */
 
 	/**
 	 * Retrieves all widget areas.
@@ -192,6 +190,9 @@ public function get_item( $request ) {
 	 *
 	 * @param WP_REST_Request $request Full details about the request.
 	 * @return WP_Error|bool True if the request has access to update the item, error object otherwise.
+	 *
+	 * This function is overloading a function defined in WP_REST_Controller so it should have the same parameters.
+	 * phpcs:disable VariableAnalysis.CodeAnalysis.VariableAnalysis.UnusedVariable
 	 */
 	public function update_item_permissions_check( $request ) {
 		if ( ! current_user_can( 'edit_theme_options' ) ) {
@@ -203,6 +204,7 @@ public function update_item_permissions_check( $request ) {
 
 		return true;
 	}
+	/* phpcs:enable */
 
 	/**
 	 * Updates a single widget area.

lib/class-wp-rest-widget-areas-controller.php

@@ -85,8 +85,6 @@ public function compute_new_widget_permissions_check() {
 	 * @return WP_REST_Response|WP_Error Response object on success, or WP_Error object on failure.
 	 */
 	public function compute_new_widget( $request ) {
-		$url_params = $request->get_url_params();
-
 		$widget = $request->get_param( 'identifier' );
 
 		global $wp_widget_factory;

lib/class-wp-rest-widget-updater-controller.php

@@ -240,7 +240,6 @@ function gutenberg_register_scripts_and_styles() {
 	//
 	// See: https://core.trac.wordpress.org/ticket/46107 .
 	// See: https://github.com/WordPress/gutenberg/pull/13451 .
-	global $wp_scripts;
 	if ( isset( $wp_scripts->registered['wp-api-fetch'] ) ) {
 		$wp_scripts->registered['wp-api-fetch']->deps[] = 'wp-hooks';
 	}

lib/client-assets.php

@@ -9,10 +9,8 @@
  * The main entry point for the Gutenberg experiments page.
  *
  * @since 6.3.0
- *
- * @param string $page The page name the function is being called for, `'gutenberg_customizer'` for the Customizer.
  */
-function the_gutenberg_experiments( $page = 'gutenberg_page_gutenberg-experiments' ) {
+function the_gutenberg_experiments() {
 	?>
 	<div
 		id="experiments-editor"

lib/experiments-page.php

@@ -10,6 +10,11 @@
 	<rule ref="WordPress.WP.I18n"/>
 	<config name="text_domain" value="gutenberg,default"/>
 
+	<rule ref="VariableAnalysis.CodeAnalysis.VariableAnalysis">
+		<properties>
+			<property name="allowUnusedParametersBeforeUsed" value="true"/>
+		</properties>
+	</rule>
 	<rule ref="WordPress.CodeAnalysis.EmptyStatement"/>
 
 	<rule ref="PEAR.Functions.FunctionCallSignature">