Enforce checks against redeclaration for functions and classes (#52696)

Enforce checks against redeclaration for functions and classes.
See https://github.com/WordPress/gutenberg/blob/trunk/lib/README.md#wrap-functions-and-classes-with--function_exists-and--class_exists
Props: @tellthemachines @azaozz @ramonjd @anton-vlasenko

.github/CODEOWNERS

@@ -82,6 +82,7 @@
 /packages/scripts                               @gziolo @ntwb @nerrad @ajitbohra @ryanwelcher
 /packages/stylelint-config                      @ntwb
 /test/e2e                                       @kevin940726 @Mamaduka
+/test/php/gutenberg-coding-standards			@anton-vlasenko
 
 # UI Components
 /packages/components                            @ajitbohra

composer.json

@@ -32,8 +32,18 @@
 		"wp-coding-standards/wpcs": "^2.2",
 		"sirbrillig/phpcs-variable-analysis": "^2.8",
 		"spatie/phpunit-watcher": "^1.23",
-		"yoast/phpunit-polyfills": "^1.0"
+		"yoast/phpunit-polyfills": "^1.0",
+		"gutenberg/gutenberg-coding-standards": "@dev"
 	},
+	"repositories": [
+		{
+			"type": "path",
+			"url": "./test/php/gutenberg-coding-standards",
+			"options": {
+				"symlink": false
+			}
+		}
+	],
 	"require": {
 		"composer/installers": "~1.0"
 	},

lib/class-wp-duotone-gutenberg.php

@@ -32,6 +32,10 @@
  * @since 6.3.0
  */
 
+if ( class_exists( 'WP_Duotone_Gutenberg' ) ) {
+	return;
+}
+
 /**
  * Manages duotone block supports and global styles.
  *

lib/class-wp-theme-json-data-gutenberg.php

@@ -6,6 +6,10 @@
  * @since 6.1.0
  */
 
+if ( class_exists( 'WP_Theme_JSON_Data_Gutenberg' ) ) {
+	return;
+}
+
 /**
  * Class to provide access to update a theme.json structure.
  */

lib/class-wp-theme-json-gutenberg.php

@@ -6,6 +6,10 @@
  * @since 5.8.0
  */
 
+if ( class_exists( 'WP_Theme_JSON_Gutenberg' ) ) {
+	return;
+}
+
 /**
  * Class that encapsulates the processing of structures that adhere to the theme.json spec.
  *

lib/class-wp-theme-json-resolver-gutenberg.php

@@ -6,6 +6,10 @@
  * @since 5.8.0
  */
 
+if ( class_exists( 'WP_Theme_JSON_Resolver_Gutenberg' ) ) {
+	return;
+}
+
 /**
  * Class that abstracts the processing of the different data sources
  * for site-level config and offers an API to work with them.

lib/compat/wordpress-6.2/html-api/class-wp-html-attribute-token.php

@@ -7,6 +7,10 @@
  * @since 6.2.0
  */
 
+if ( class_exists( 'WP_HTML_Attribute_Token' ) ) {
+	return;
+}
+
 /**
  * Data structure for the attribute token that allows to drastically improve performance.
  *

lib/compat/wordpress-6.2/html-api/class-wp-html-span.php

@@ -7,6 +7,10 @@
  * @since 6.2.0
  */
 
+if ( class_exists( 'WP_HTML_Span' ) ) {
+	return;
+}
+
 /**
  * Represents a textual span inside an HTML document.
  *

lib/compat/wordpress-6.2/html-api/class-wp-html-tag-processor.php

@@ -26,6 +26,10 @@
  * @since 6.2.0
  */
 
+if ( class_exists( 'WP_HTML_Tag_Processor' ) ) {
+	return;
+}
+
 /**
  * Modifies attributes in an HTML document for tags matching a query.
  *

lib/compat/wordpress-6.2/html-api/class-wp-html-text-replacement.php

@@ -7,6 +7,10 @@
  * @since 6.2.0
  */
 
+if ( class_exists( 'WP_HTML_Text_Replacement' ) ) {
+	return;
+}
+
 /**
  * Data structure used to replace existing content from start to end that allows to drastically improve performance.
  *

lib/compat/wordpress-6.2/rest-api.php

@@ -91,43 +91,46 @@ function gutenberg_modify_rest_sidebars_response( $response ) {
 }
 add_filter( 'rest_prepare_sidebar', 'gutenberg_modify_rest_sidebars_response' );
 
-
-/**
- * Add the `block_types` value to the `pattern-directory-item` schema.
- *
- * @since 6.2.0 Added 'block_types' property.
- */
-function add_block_pattern_block_types_schema() {
-	register_rest_field(
-		'pattern-directory-item',
-		'block_types',
-		array(
-			'schema' => array(
-				'description' => __( 'The block types which can use this pattern.', 'gutenberg' ),
-				'type'        => 'array',
-				'uniqueItems' => true,
-				'items'       => array( 'type' => 'string' ),
-				'context'     => array( 'view', 'embed' ),
-			),
-		)
-	);
+if ( ! function_exists( 'add_block_pattern_block_types_schema' ) ) {
+	/**
+	 * Add the `block_types` value to the `pattern-directory-item` schema.
+	 *
+	 * @since 6.2.0 Added 'block_types' property.
+	 */
+	function add_block_pattern_block_types_schema() {
+		register_rest_field(
+			'pattern-directory-item',
+			'block_types',
+			array(
+				'schema' => array(
+					'description' => __( 'The block types which can use this pattern.', 'gutenberg' ),
+					'type'        => 'array',
+					'uniqueItems' => true,
+					'items'       => array( 'type' => 'string' ),
+					'context'     => array( 'view', 'embed' ),
+				),
+			)
+		);
+	}
 }
 add_filter( 'rest_api_init', 'add_block_pattern_block_types_schema' );
 
 
-/**
- * Add the `block_types` value into the API response.
- *
- * @since 6.2.0 Added 'block_types' property.
- *
- * @param WP_REST_Response $response    The response object.
- * @param object           $raw_pattern The unprepared pattern.
- */
-function filter_block_pattern_response( $response, $raw_pattern ) {
-	$data                = $response->get_data();
-	$data['block_types'] = array_map( 'sanitize_text_field', $raw_pattern->meta->wpop_block_types );
-	$response->set_data( $data );
-	return $response;
+if ( ! function_exists( 'filter_block_pattern_response' ) ) {
+	/**
+	 * Add the `block_types` value into the API response.
+	 *
+	 * @since 6.2.0 Added 'block_types' property.
+	 *
+	 * @param WP_REST_Response $response    The response object.
+	 * @param object           $raw_pattern The unprepared pattern.
+	 */
+	function filter_block_pattern_response( $response, $raw_pattern ) {
+		$data                = $response->get_data();
+		$data['block_types'] = array_map( 'sanitize_text_field', $raw_pattern->meta->wpop_block_types );
+		$response->set_data( $data );
+		return $response;
+	}
 }
 add_filter( 'rest_prepare_block_pattern', 'filter_block_pattern_response', 10, 2 );
 

lib/compat/wordpress-6.3/kses.php

@@ -7,21 +7,23 @@
  * @package gutenberg
  */
 
-/**
- * Mark CSS safe if it contains grid functions
- *
- * This function should not be backported to core.
- *
- * @param bool   $allow_css Whether the CSS is allowed.
- * @param string $css_test_string The CSS to test.
- */
-function allow_grid_functions_in_styles( $allow_css, $css_test_string ) {
-	if ( preg_match(
-		'/^grid-template-columns:\s*repeat\([0-9,a-z-\s\(\)]*\)$/',
-		$css_test_string
-	) ) {
-		return true;
+if ( ! function_exists( 'allow_grid_functions_in_styles' ) ) {
+	/**
+	 * Mark CSS safe if it contains grid functions
+	 *
+	 * This function should not be backported to core.
+	 *
+	 * @param bool   $allow_css Whether the CSS is allowed.
+	 * @param string $css_test_string The CSS to test.
+	 */
+	function allow_grid_functions_in_styles( $allow_css, $css_test_string ) {
+		if ( preg_match(
+			'/^grid-template-columns:\s*repeat\([0-9,a-z-\s\(\)]*\)$/',
+			$css_test_string
+		) ) {
+			return true;
+		}
+		return $allow_css;
 	}
-	return $allow_css;
 }
 add_filter( 'safecss_filter_attr_allow_css', 'allow_grid_functions_in_styles', 10, 2 );

lib/compat/wordpress-6.3/rest-api.php

@@ -52,12 +52,13 @@ function gutenberg_update_templates_template_parts_rest_controller( $args, $post
 }
 add_filter( 'register_post_type_args', 'gutenberg_update_templates_template_parts_rest_controller', 10, 2 );
 
-/**
- * Add the `modified` value to the `wp_template` schema.
- *
- * @since 6.3.0 Added 'modified' property and response value.
- */
-function add_modified_wp_template_schema() {
+if ( ! function_exists( 'add_modified_wp_template_schema' ) ) {
+	/**
+	 * Add the `modified` value to the `wp_template` schema.
+	 *
+	 * @since 6.3.0 Added 'modified' property and response value.
+	 */
+	function add_modified_wp_template_schema() {
 		register_rest_field(
 			array( 'wp_template', 'wp_template_part' ),
 			'modified',
@@ -80,6 +81,7 @@ function add_modified_wp_template_schema() {
 				},
 			)
 		);
+	}
 }
 add_filter( 'rest_api_init', 'add_modified_wp_template_schema' );
 

lib/compat/wordpress-6.3/theme-previews.php

@@ -51,14 +51,15 @@ function gutenberg_attach_theme_preview_middleware() {
 	);
 }
 
-/**
- * Temporary function to add a live preview button to block themes.
- * Remove when https://core.trac.wordpress.org/ticket/58190 lands.
- */
-function add_live_preview_button() {
-	global $pagenow;
-	if ( 'themes.php' === $pagenow ) {
-		?>
+if ( ! function_exists( 'add_live_preview_button' ) ) {
+	/**
+	 * Temporary function to add a live preview button to block themes.
+	 * Remove when https://core.trac.wordpress.org/ticket/58190 lands.
+	 */
+	function add_live_preview_button() {
+		global $pagenow;
+		if ( 'themes.php' === $pagenow ) {
+			?>
 <script type="text/javascript">
 	jQuery( document ).ready( function() {
 		addLivePreviewButton();
@@ -95,21 +96,23 @@ function addLivePreviewButton() {
 		});
 	}
 </script>
-		<?php
+			<?php
+		}
 	}
-
 }
 
-/**
- * Adds a nonce for the theme activation link.
- */
-function block_theme_activate_nonce() {
-	$nonce_handle = 'switch-theme_' . gutenberg_get_theme_preview_path();
-	?>
+if ( ! function_exists( 'block_theme_activate_nonce' ) ) {
+	/**
+	 * Adds a nonce for the theme activation link.
+	 */
+	function block_theme_activate_nonce() {
+		$nonce_handle = 'switch-theme_' . gutenberg_get_theme_preview_path();
+		?>
 <script type="text/javascript">
 	window.WP_BLOCK_THEME_ACTIVATE_NONCE = '<?php echo wp_create_nonce( $nonce_handle ); ?>';
 </script>
-	<?php
+		<?php
+	}
 }
 
 /**

lib/experimental/class--wp-editors.php

@@ -8,6 +8,10 @@
 
 // phpcs:disable PEAR.NamingConventions.ValidClassName.StartWithCapital
 
+if ( class_exists( '_WP_Editors' ) ) {
+	return;
+}
+
 /**
  * Placeholder class.
  * Used to disable loading of TinyMCE assets.

lib/experimental/class-wp-rest-block-editor-settings-controller.php

@@ -6,6 +6,10 @@
  * @subpackage REST_API
  */
 
+if ( class_exists( 'WP_REST_Block_Editor_Settings_Controller' ) ) {
+	return;
+}
+
 /**
  * Core class used to retrieve the block editor settings via the REST API.
  *

lib/experimental/class-wp-rest-customizer-nonces.php

@@ -5,6 +5,10 @@
  * @package gutenberg
  */
 
+if ( class_exists( 'WP_Rest_Customizer_Nonces' ) ) {
+	return;
+}
+
 /**
  * Class that returns the customizer "save" nonce that's required for the
  * batch save operation using the customizer API endpoint.

lib/experimental/interactivity-api/class-wp-directive-context.php

@@ -6,6 +6,10 @@
  * @subpackage Interactivity API
  */
 
+if ( class_exists( 'WP_Directive_Context' ) ) {
+	return;
+}
+
 /**
  * This is a data structure to hold the current context.
  *

lib/experimental/interactivity-api/class-wp-directive-processor.php

@@ -6,6 +6,10 @@
  * @subpackage Interactivity API
  */
 
+if ( class_exists( 'WP_Directive_Processor' ) ) {
+	return;
+}
+
 /**
  * This processor is built on top of the HTML Tag Processor and augments its
  * capabilities to process the Interactivity API directives.

lib/experimental/interactivity-api/class-wp-interactivity-store.php

@@ -9,6 +9,10 @@
  * @subpackage Interactivity API
  */
 
+if ( class_exists( 'WP_Interactivity_Store' ) ) {
+	return;
+}
+
 /**
  * Manages the initial state of the Interactivity API store in the server and
  * its serialization so it can be restored in the browser upon hydration.