Editor: Register the core entity actions on the server

Gruntfile.js

@@ -697,7 +697,7 @@ module.exports = function(grunt) {
 				src: 'vendor/composer/ca-bundle/res/cacert.pem',
 				dest: SOURCE_DIR + 'wp-includes/certificates/ca-bundle.crt'
 			},
-			// Gutenberg PHP infrastructure files (routes.php, pages.php, constants.php, pages/).
+			// Gutenberg PHP infrastructure files (routes.php, pages.php, constants.php, pages/, core actions).
 			'gutenberg-php': {
 				options: {
 					process: function( content ) {
@@ -716,6 +716,8 @@ module.exports = function(grunt) {
 						'pages.php',
 						'constants.php',
 						'pages/**/*.php',
+						// The actions Core registers through the entity actions API.
+						'scripts/core-actions/**/*.php',
 					],
 					dest: SOURCE_DIR + 'wp-includes/build/',
 				} ],

src/wp-includes/default-filters.php

@@ -855,6 +855,7 @@
 
 // Entity Actions API.
 add_action( 'admin_footer', '_wp_add_entity_action_modules_to_editor_script', 10, 0 );
+add_filter( 'block_editor_rest_api_preload_paths', '_wp_preload_entity_actions', 10, 2 );
 
 // Entity Fields API.
 add_action( 'admin_footer', '_wp_add_entity_field_modules_to_editor_script', 10, 0 );

src/wp-includes/entity-actions.php

@@ -15,7 +15,8 @@
  *
  * Actions are registered on the `wp_entity_actions_api_init` action, and only there,
  * with {@see wp_register_entity_actions()} and {@see wp_unregister_entity_actions()}. The
- * other functions read the registry.
+ * other functions read the registry. WordPress core registers its own
+ * actions the same way, from packages/core-actions.
  *
  * @package WordPress
  * @subpackage Entity Actions
@@ -186,3 +187,32 @@ function _wp_add_entity_action_modules_to_editor_script( $scripts = null ) {
 		$scripts->add_data( 'wp-editor', 'module_dependencies', $dependencies );
 	}
 }
+
+/**
+ * Preloads the actions of the post type the post editor edits.
+ *
+ * The actions menu of the post editor reads them from the `wp/v2/entity-actions`
+ * route as it loads, see `useEntityActions()` in
+ * packages/editor/src/dataviews/entity-actions-loader.ts. The path must match the
+ * request of the `getEntityActionsConfig` core data resolver, see
+ * packages/core-data/src/resolvers.js.
+ *
+ * @since 7.2.0
+ *
+ * @param array                   $paths   REST API paths to preload.
+ * @param WP_Block_Editor_Context $context Block editor context.
+ * @return array Filtered preload paths.
+ */
+function _wp_preload_entity_actions( $paths, $context ) {
+	if ( 'core/edit-post' === $context->name && isset( $context->post ) ) {
+		$paths[] = add_query_arg(
+			array(
+				'kind' => 'postType',
+				'name' => $context->post->post_type,
+			),
+			'/wp/v2/entity-actions'
+		);
+	}
+
+	return $paths;
+}

src/wp-settings.php

@@ -254,6 +254,9 @@
 if ( file_exists( ABSPATH . WPINC . '/build/pages.php' ) ) {
 	require ABSPATH . WPINC . '/build/pages.php';
 }
+if ( file_exists( ABSPATH . WPINC . '/build/scripts/core-actions/index.php' ) ) {
+	require ABSPATH . WPINC . '/build/scripts/core-actions/index.php';
+}
 require ABSPATH . WPINC . '/taxonomy.php';
 require ABSPATH . WPINC . '/class-wp-taxonomy.php';
 require ABSPATH . WPINC . '/class-wp-term.php';

tests/phpunit/tests/entity-actions.php

@@ -8,6 +8,7 @@
  * @group entity-actions
  *
  * @covers ::_wp_add_entity_action_modules_to_editor_script
+ * @covers ::_wp_preload_entity_actions
  * @covers ::wp_register_entity_actions
  * @covers ::wp_unregister_entity_actions
  * @covers WP_Entity_Actions_Registry::initialize
@@ -17,12 +18,15 @@
 class Tests_Entity_Actions extends WP_UnitTestCase {
 
 	/**
-	 * Sets up each test: the default actions of the tests are registered at
-	 * priority 0, so every test runs against a registry holding actions
-	 * registered before the callbacks hooked at the default priority run.
+	 * Sets up each test: the actions WordPress registers are replaced with
+	 * the default actions of the tests, hooked at priority 0 as WordPress
+	 * registers its own, so every test runs against a registry holding
+	 * actions registered before the callbacks hooked at the default priority
+	 * run.
 	 */
 	public function set_up() {
 		parent::set_up();
+		remove_action( 'wp_entity_actions_api_init', 'register_core_entity_actions', 0 );
 		add_action( 'wp_entity_actions_api_init', array( __CLASS__, 'register_default_actions' ), 0 );
 	}
 
@@ -31,8 +35,9 @@ public function set_up() {
 	 *
 	 * Resetting the registry drops the actions a test registered along with
 	 * the defaults; the next read fires `wp_entity_actions_api_init` again and
-	 * registers the defaults anew. The test case removes the callbacks the
-	 * test hooked, the defaults included.
+	 * registers the defaults anew. The test case restores the hooks: it
+	 * removes the callbacks the test hooked, the defaults included, and hooks
+	 * the actions WordPress registers back.
 	 */
 	public function tear_down() {
 		self::reset_registry();
@@ -387,6 +392,51 @@ public function test_action_script_modules_reach_the_import_map() {
 		$this->assertArrayHasKey( 'plugin/feature', $import_map['imports'] );
 	}
 
+	/**
+	 * The post editor preloads the actions of the post type it edits, with
+	 * the path the `getEntityActionsConfig` resolver of core data requests.
+	 *
+	 * @ticket 66343
+	 */
+	public function test_the_post_editor_preloads_the_actions_of_the_post_type() {
+		$context = new WP_Block_Editor_Context( array( 'post' => self::factory()->post->create_and_get( array( 'post_type' => 'page' ) ) ) );
+
+		$paths = apply_filters( 'block_editor_rest_api_preload_paths', array(), $context );
+
+		$this->assertContains( '/wp/v2/entity-actions?kind=postType&name=page', $paths, 'The actions of pages are preloaded.' );
+	}
+
+	/**
+	 * The preloaded path serves the actions of the post type.
+	 *
+	 * @ticket 66343
+	 */
+	public function test_the_preloaded_actions_path_serves_the_actions() {
+		wp_set_current_user( self::factory()->user->create( array( 'role' => 'administrator' ) ) );
+		$context = new WP_Block_Editor_Context( array( 'post' => self::factory()->post->create_and_get( array( 'post_type' => 'page' ) ) ) );
+
+		$paths     = _wp_preload_entity_actions( array(), $context );
+		$preloaded = array_reduce( $paths, 'rest_preload_api_request', array() );
+
+		$this->assertSame(
+			array( 'rename-post', 'move-to-trash' ),
+			array_column( $preloaded['/wp/v2/entity-actions?kind=postType&name=page']['body']['actions'], 'id' ),
+			'The preloaded response holds the actions of pages.'
+		);
+	}
+
+	/**
+	 * Only the post editor preloads the actions: the other editors have no
+	 * post type of their own.
+	 *
+	 * @ticket 66343
+	 */
+	public function test_other_editors_do_not_preload_the_actions() {
+		$context = new WP_Block_Editor_Context( array( 'name' => 'core/edit-site' ) );
+
+		$this->assertSame( array( '/wp/v2/types' ), _wp_preload_entity_actions( array( '/wp/v2/types' ), $context ), 'The paths are unchanged.' );
+	}
+
 	/**
 	 * Reading the registry fires `wp_entity_actions_api_init` once, whichever
 	 * getter is read first and however many times it is read.