Fix metabox reordering

packages/edit-post/README.md

@@ -37,11 +37,15 @@ call initializeEditor(). This is due to metaBox timing.
 _Parameters_
 
 -   _id_ `string`: Unique identifier for editor instance.
--   _postType_ `Object`: Post type of the post to edit.
+-   _postType_ `string`: Post type of the post to edit.
 -   _postId_ `Object`: ID of the post to edit.
 -   _settings_ `?Object`: Editor settings object.
 -   _initialEdits_ `Object`: Programmatic edits to apply initially, to be considered as non-user-initiated (bypass for unsaved changes prompt).
 
+_Returns_
+
+-   `Promise`: Promise that resolves when editor is initialized.
+
 <a name="PluginBlockSettingsMenuItem" href="#PluginBlockSettingsMenuItem">#</a> **PluginBlockSettingsMenuItem**
 
 Renders a new item in the block settings menu.

packages/edit-post/src/editor.js

@@ -35,6 +35,7 @@ function Editor( {
 	settings,
 	initialEdits,
 	onError,
+	markEditorReady,
 	...props
 } ) {
 	const {
@@ -50,6 +51,7 @@ function Editor( {
 		keepCaretInsideBlock,
 		isTemplateMode,
 		template,
+		isEditorReady,
 	} = useSelect( ( select ) => {
 		const {
 			isFeatureActive,
@@ -61,7 +63,9 @@ function Editor( {
 		const { getEntityRecord, getPostType, getEntityRecords } = select(
 			'core'
 		);
-		const { getEditorSettings } = select( 'core/editor' );
+		const { getEditorSettings, __unstableIsEditorReady } = select(
+			'core/editor'
+		);
 		const { getBlockTypes } = select( blocksStore );
 		const isTemplate = [ 'wp_template', 'wp_template_part' ].includes(
 			postType
@@ -102,6 +106,7 @@ function Editor( {
 					? getEditedPostTemplate()
 					: null,
 			post: postObject,
+			isEditorReady: __unstableIsEditorReady(),
 		};
 	} );
 
@@ -165,6 +170,14 @@ function Editor( {
 		return null;
 	}
 
+	/**
+	 * Some features like back compat metaboxes rely on editor notifying that
+	 * it's ready by calling markEditorReady.
+	 */
+	if ( markEditorReady && isEditorReady ) {
+		markEditorReady();
+	}
+
 	return (
 		<StrictMode>
 			<EditPostSettings.Provider value={ settings }>

packages/edit-post/src/index.js

@@ -15,7 +15,6 @@ import { render, unmountComponentAtNode } from '@wordpress/element';
  */
 import './hooks';
 import './plugins';
-export { store } from './store';
 import Editor from './editor';
 
 /**
@@ -68,12 +67,13 @@ export function reinitializeEditor(
  * call initializeEditor(). This is due to metaBox timing.
  *
  * @param {string}  id           Unique identifier for editor instance.
- * @param {Object}  postType     Post type of the post to edit.
+ * @param {string}  postType     Post type of the post to edit.
  * @param {Object}  postId       ID of the post to edit.
  * @param {?Object} settings     Editor settings object.
  * @param {Object}  initialEdits Programmatic edits to apply initially, to be
  *                               considered as non-user-initiated (bypass for
  *                               unsaved changes prompt).
+ * @return {Promise} Promise that resolves when editor is initialized.
  */
 export function initializeEditor(
 	id,
@@ -138,16 +138,19 @@ export function initializeEditor(
 		} );
 	}
 
-	render(
-		<Editor
-			settings={ settings }
-			onError={ reboot }
-			postId={ postId }
-			postType={ postType }
-			initialEdits={ initialEdits }
-		/>,
-		target
-	);
+	return new Promise( ( resolve ) => {
+		render(
+			<Editor
+				settings={ settings }
+				onError={ reboot }
+				postId={ postId }
+				postType={ postType }
+				initialEdits={ initialEdits }
+				markEditorReady={ resolve }
+			/>,
+			target
+		);
+	} );
 }
 
 export { default as PluginBlockSettingsMenuItem } from './components/block-settings-menu/plugin-block-settings-menu-item';
@@ -160,3 +163,4 @@ export { default as PluginSidebar } from './components/sidebar/plugin-sidebar';
 export { default as PluginSidebarMoreMenuItem } from './components/header/plugin-sidebar-more-menu-item';
 export { default as __experimentalFullscreenModeClose } from './components/header/fullscreen-mode-close';
 export { default as __experimentalMainDashboardButton } from './components/header/main-dashboard-button';
+export { store } from './store';