Async mode in the data module

docs/manifest.json

@@ -725,6 +725,12 @@
 		"markdown_source": "https://raw.githubusercontent.com/WordPress/gutenberg/master/packages/postcss-themes/README.md",
 		"parent": "packages"
 	},
+	{
+		"title": "@wordpress/priority-queue",
+		"slug": "packages-priority-queue",
+		"markdown_source": "https://raw.githubusercontent.com/WordPress/gutenberg/master/packages/priority-queue/README.md",
+		"parent": "packages"
+	},
 	{
 		"title": "@wordpress/redux-routine",
 		"slug": "packages-redux-routine",

lib/packages-dependencies.php

@@ -91,6 +91,7 @@
 		'wp-compose',
 		'wp-element',
 		'wp-is-shallow-equal',
+		'wp-priority-queue',
 		'wp-redux-routine',
 	),
 	'wp-date'                               => array(
@@ -211,6 +212,7 @@
 		'wp-element',
 		'wp-hooks',
 	),
+	'wp-priority-queue'                     => array(),
 	'wp-redux-routine'                      => array(),
 	'wp-rich-text'                          => array(
 		'lodash',

package.json

@@ -42,6 +42,7 @@
 		"@wordpress/notices": "file:packages/notices",
 		"@wordpress/nux": "file:packages/nux",
 		"@wordpress/plugins": "file:packages/plugins",
+		"@wordpress/priority-queue": "file:packages/priority-queue",
 		"@wordpress/redux-routine": "file:packages/redux-routine",
 		"@wordpress/rich-text": "file:packages/rich-text",
 		"@wordpress/shortcode": "file:packages/shortcode",

packages/data/package.json

@@ -25,6 +25,7 @@
 		"@wordpress/compose": "file:../compose",
 		"@wordpress/element": "file:../element",
 		"@wordpress/is-shallow-equal": "file:../is-shallow-equal",
+		"@wordpress/priority-queue": "file:../priority-queue",
 		"@wordpress/redux-routine": "file:../redux-routine",
 		"equivalent-key-map": "^0.2.2",
 		"is-promise": "^2.1.0",

packages/data/src/components/async-mode-provider/index.js

@@ -0,0 +1,10 @@
+/**
+ * WordPress dependencies
+ */
+import { createContext } from '@wordpress/element';
+
+const { Consumer, Provider } = createContext( false );
+
+export const AsyncModeConsumer = Consumer;
+
+export default Provider;

packages/data/src/components/with-select/index.js

@@ -4,11 +4,15 @@
 import { Component } from '@wordpress/element';
 import { isShallowEqualObjects } from '@wordpress/is-shallow-equal';
 import { createHigherOrderComponent } from '@wordpress/compose';
+import { createQueue } from '@wordpress/priority-queue';
 
 /**
  * Internal dependencies
  */
 import { RegistryConsumer } from '../registry-provider';
+import { AsyncModeConsumer } from '../async-mode-provider';
+
+const renderQueue = createQueue();
 
 /**
  * Higher-order component used to inject state-derived props using registered
@@ -70,16 +74,23 @@ const withSelect = ( mapSelectToProps ) => createHigherOrderComponent( ( Wrapped
 		componentWillUnmount() {
 			this.canRunSelection = false;
 			this.unsubscribe();
+			renderQueue.flush( this );
 		}
 
 		shouldComponentUpdate( nextProps, nextState ) {
 			// Cycle subscription if registry changes.
 			const hasRegistryChanged = nextProps.registry !== this.props.registry;
+			const hasSyncRenderingChanged = nextProps.isAsync !== this.props.isAsync;
+
 			if ( hasRegistryChanged ) {
 				this.unsubscribe();
 				this.subscribe( nextProps.registry );
 			}
 
+			if ( hasSyncRenderingChanged ) {
+				renderQueue.flush( this );
+			}
+
 			// Treat a registry change as equivalent to `ownProps`, to reflect
 			// `mergeProps` to rendered component if and only if updated.
 			const hasPropsChanged = (
@@ -89,11 +100,11 @@ const withSelect = ( mapSelectToProps ) => createHigherOrderComponent( ( Wrapped
 
 			// Only render if props have changed or merge props have been updated
 			// from the store subscriber.
-			if ( this.state === nextState && ! hasPropsChanged ) {
+			if ( this.state === nextState && ! hasPropsChanged && ! hasSyncRenderingChanged ) {
 				return false;
 			}
 
-			if ( hasPropsChanged ) {
+			if ( hasPropsChanged || hasSyncRenderingChanged ) {
 				const nextMergeProps = getNextMergeProps( nextProps );
 				if ( ! isShallowEqualObjects( this.mergeProps, nextMergeProps ) ) {
 					// If merge props change as a result of the incoming props,
@@ -137,7 +148,13 @@ const withSelect = ( mapSelectToProps ) => createHigherOrderComponent( ( Wrapped
 		}
 
 		subscribe( registry ) {
-			this.unsubscribe = registry.subscribe( this.onStoreChange );
+			this.unsubscribe = registry.subscribe( () => {
+				if ( this.props.isAsync ) {
+					renderQueue.add( this, this.onStoreChange );
+				} else {
+					this.onStoreChange();
+				}
+			} );
 		}
 
 		render() {
@@ -146,14 +163,19 @@ const withSelect = ( mapSelectToProps ) => createHigherOrderComponent( ( Wrapped
 	}
 
 	return ( ownProps ) => (
-		<RegistryConsumer>
-			{ ( registry ) => (
-				<ComponentWithSelect
-					ownProps={ ownProps }
-					registry={ registry }
-				/>
+		<AsyncModeConsumer>
+			{ ( isAsync ) => (
+				<RegistryConsumer>
+					{ ( registry ) => (
+						<ComponentWithSelect
+							ownProps={ ownProps }
+							registry={ registry }
+							isAsync={ isAsync }
+						/>
+					) }
+				</RegistryConsumer>
 			) }
-		</RegistryConsumer>
+		</AsyncModeConsumer>
 	);
 }, 'withSelect' );
 

packages/data/src/index.js

@@ -12,6 +12,7 @@ import * as plugins from './plugins';
 export { default as withSelect } from './components/with-select';
 export { default as withDispatch } from './components/with-dispatch';
 export { default as RegistryProvider, RegistryConsumer } from './components/registry-provider';
+export { default as __experimentalAsyncModeProvider } from './components/async-mode-provider';
 export { createRegistry } from './registry';
 export { plugins };
 

packages/e2e-tests/specs/plugins/meta-attribute-block.test.js

@@ -40,9 +40,12 @@ describe( 'Block with a meta attribute', () => {
 		await insertBlock( 'Test Meta Attribute Block' );
 		await page.keyboard.type( 'Meta Value' );
 
-		const persistedValues = await page.evaluate( () => Array.from( document.querySelectorAll( '.my-meta-input' ) ).map( ( input ) => input.value ) );
-		persistedValues.forEach( ( val ) => {
-			expect( val ).toBe( 'Meta Value' );
+		const inputs = await page.$$( '.my-meta-input' );
+		await inputs.forEach( async ( input ) => {
+			// Clicking the input selects the block,
+			// and selecting the block enables the sync data mode.
+			await input.click();
+			expect( await input.getProperty( 'value' ) ).toBe( 'Meta Value' );
 		} );
 	} );
 } );

packages/editor/src/components/block-list/index.js

@@ -14,7 +14,11 @@ import {
  * WordPress dependencies
  */
 import { Component } from '@wordpress/element';
-import { withSelect, withDispatch } from '@wordpress/data';
+import {
+	withSelect,
+	withDispatch,
+	__experimentalAsyncModeProvider as AsyncModeProvider,
+} from '@wordpress/data';
 import { compose } from '@wordpress/compose';
 
 /**
@@ -24,6 +28,13 @@ import BlockListBlock from './block';
 import BlockListAppender from '../block-list-appender';
 import { getBlockDOMNode } from '../../utils/dom';
 
+const forceSyncUpdates = ( WrappedComponent ) => ( props ) => {
+	return (
+		<AsyncModeProvider value={ false }>
+			<WrappedComponent { ...props } />
+		</AsyncModeProvider>
+	);
+};
 class BlockList extends Component {
 	constructor( props ) {
 		super( props );
@@ -182,37 +193,54 @@ class BlockList extends Component {
 			blockClientIds,
 			rootClientId,
 			isDraggable,
+			selectedBlockClientId,
+			multiSelectedBlockClientIds,
 		} = this.props;
 
 		return (
 			<div className="editor-block-list__layout">
-				{ map( blockClientIds, ( clientId, blockIndex ) => (
-					<BlockListBlock
-						key={ 'block-' + clientId }
-						index={ blockIndex }
-						clientId={ clientId }
-						blockRef={ this.setBlockRef }
-						onSelectionStart={ this.onSelectionStart }
-						rootClientId={ rootClientId }
-						isFirst={ blockIndex === 0 }
-						isLast={ blockIndex === blockClientIds.length - 1 }
-						isDraggable={ isDraggable }
-					/>
-				) ) }
+				{ map( blockClientIds, ( clientId, blockIndex ) => {
+					return (
+						<AsyncModeProvider
+							key={ 'block-' + clientId }
+							value={
+								selectedBlockClientId !== clientId &&
+							( !! selectedBlockClientId || multiSelectedBlockClientIds.indexOf( clientId ) === -1 )
+							}
+						>
+							<BlockListBlock
+								clientId={ clientId }
+								index={ blockIndex }
+								blockRef={ this.setBlockRef }
+								onSelectionStart={ this.onSelectionStart }
+								rootClientId={ rootClientId }
+								isFirst={ blockIndex === 0 }
+								isLast={ blockIndex === blockClientIds.length - 1 }
+								isDraggable={ isDraggable }
+							/>
+						</AsyncModeProvider>
+					);
+				} ) }
 				<BlockListAppender rootClientId={ rootClientId } />
 			</div>
 		);
 	}
 }
 
 export default compose( [
+	// This component needs to always be synchronous
+	// as it's the one changing the async mode
+	// depending on the block selection.
+	forceSyncUpdates,
 	withSelect( ( select, ownProps ) => {
 		const {
 			getBlockOrder,
 			isSelectionEnabled,
 			isMultiSelecting,
 			getMultiSelectedBlocksStartClientId,
 			getMultiSelectedBlocksEndClientId,
+			getSelectedBlockClientId,
+			getMultiSelectedBlockClientIds,
 		} = select( 'core/editor' );
 		const { rootClientId } = ownProps;
 
@@ -222,6 +250,8 @@ export default compose( [
 			selectionEnd: getMultiSelectedBlocksEndClientId(),
 			isSelectionEnabled: isSelectionEnabled(),
 			isMultiSelecting: isMultiSelecting(),
+			selectedBlockClientId: getSelectedBlockClientId(),
+			multiSelectedBlockClientIds: getMultiSelectedBlockClientIds(),
 		};
 	} ),
 	withDispatch( ( dispatch ) => {

packages/priority-queue/.npmrc

@@ -0,0 +1 @@
+package-lock=false

packages/priority-queue/CHANGELOG.md

@@ -0,0 +1,3 @@
+### 1.0.0 (Unreleased)
+
+Initial release.

packages/priority-queue/README.md

@@ -0,0 +1,32 @@
+# Priority Queue
+
+This module allows you to run a queue of callback while on the browser's idle time making sure the higher-priority work is performed first.
+
+## Installation
+
+Install the module
+
+```bash
+npm install @wordpress/priority-queue --save
+```
+
+_This package assumes that your code will run in an **ES2015+** environment. If you're using an environment that has limited or no support for ES2015+ such as lower versions of IE then using [core-js](https://github.com/zloirock/core-js) or [@babel/polyfill](https://babeljs.io/docs/en/next/babel-polyfill) will add support for these methods. Learn more about it in [Babel docs](https://babeljs.io/docs/en/next/caveats).
+
+## Usage
+
+```js
+import { createQueue } from '@wordpress/priority-queue';
+
+const queue = createQueue();
+
+// Context objects.
+const ctx1 = {};
+const ctx2 = {}; 
+
+// For a given context in the queue, only the last callback is executed.
+queue.add( ctx1, () => console.log( 'This will be printed first' ) );
+queue.add( ctx2, () => console.log( 'This won\'t be printed' ) );
+queue.add( ctx2, () => console.log( 'This will be printed second' ) );
+```
+
+<br/><br/><p align="center"><img src="https://s.w.org/style/images/codeispoetry.png?1" alt="Code is Poetry." /></p>

packages/priority-queue/package.json

@@ -0,0 +1,29 @@
+{
+	"name": "@wordpress/priority-queue",
+	"version": "1.0.0-alpha.0",
+	"description": "Generic browser priority queue.",
+	"author": "The WordPress Contributors",
+	"license": "GPL-2.0-or-later",
+	"keywords": [
+		"wordpress",
+		"browser",
+		"async"
+	],
+	"homepage": "https://github.com/WordPress/gutenberg/tree/master/packages/priority-queue/README.md",
+	"repository": {
+		"type": "git",
+		"url": "https://github.com/WordPress/gutenberg.git"
+	},
+	"bugs": {
+		"url": "https://github.com/WordPress/gutenberg/issues"
+	},
+	"main": "build/index.js",
+	"module": "build-module/index.js",
+	"react-native": "src/index",
+	"dependencies": {
+		"@babel/runtime": "^7.0.0"
+	},
+	"publishConfig": {
+		"access": "public"
+	}
+}