angular · JiaLiPassion · Sep 19, 2020
diff --git a/goldens/size-tracking/integration-payloads.json b/goldens/size-tracking/integration-payloads.json
@@ -4,7 +4,7 @@
       "uncompressed": {
         "runtime-es2015": 1485,
         "main-es2015": 140899,
-        "polyfills-es2015": 36571
+        "polyfills-es2015": 36964
       }
     }
   },
@@ -22,7 +22,7 @@
       "uncompressed": {
         "runtime-es2015": 1485,
         "main-es2015": 146698,
-        "polyfills-es2015": 36571
+        "polyfills-es2015": 36964
       }
     }
   },
@@ -31,7 +31,7 @@
       "uncompressed": {
         "runtime-es2015": 1485,
         "main-es2015": 136062,
-        "polyfills-es2015": 37392
+        "polyfills-es2015": 37641
       }
     }
   },

diff --git a/packages/zone.js/lib/browser/browser.ts b/packages/zone.js/lib/browser/browser.ts
@@ -25,6 +25,15 @@ Zone.__load_patch('legacy', (global: any) => {
   }
 });
 
+Zone.__load_patch('queueMicrotask', (global: any, Zone: ZoneType, api: _ZonePrivate) => {
+  api.patchMethod(global, 'queueMicrotask', delegate => {
+    return function(self: any, args: any[]) {
+      Zone.current.scheduleMicroTask('queueMicrotask', args[0]);
+    }
+  });
+});
+
+
 Zone.__load_patch('timers', (global: any) => {
   const set = 'set';
   const clear = 'clear';

diff --git a/packages/zone.js/lib/zone.configurations.api.ts b/packages/zone.js/lib/zone.configurations.api.ts
@@ -294,6 +294,34 @@ interface ZoneGlobalConfigurations {
    */
   __Zone_disable_requestAnimationFrame?: boolean;
 
+  /**
+   *
+   * Disable the monkey patching of the browser's `queueMicrotask()` API.
+   *
+   * By default, `zone.js` monkey patches the browser's `queueMicrotask()` API
+   * to ensure that `queueMicrotask()` callback is invoked in the same zone as zone used to invoke
+   * `queueMicrotask()`. And also the callback is running as `microTask` like
+   * `Promise.prototype.then()`.
+   *
+   * Consider the following example:
+   *
+   * ```
+   * const zone = Zone.current.fork({name: 'myZone'});
+   * zone.run(() => {
+   *   queueMicrotask(() => {
+   *     console.log('queueMicrotask() callback is invoked in the zone', Zone.current.name);
+   *     // Since `queueMicrotask()` was invoked in `myZone`, same zone is restored
+   *     // when 'queueMicrotask() callback is invoked, resulting in `myZone` being console logged.
+   *   });
+   * });
+   * ```
+   *
+   * If you set `__Zone_disable_queueMicrotask = true` before importing `zone.js`,
+   * `zone.js` does not monkey patch the `queueMicrotask()` API and the above code
+   * output will change to: 'queueMicrotask() callback is invoked in the zone <root>'.
+   */
+  __Zone_disable_queueMicrotask?: boolean;
+
   /**
    *
    * Disable the monkey patch of the browser blocking APIs(`alert()`/`prompt()`/`confirm()`).

diff --git a/packages/zone.js/test/browser/queue-microtask.spec.ts b/packages/zone.js/test/browser/queue-microtask.spec.ts
@@ -0,0 +1,33 @@
+/**
+ * @license
+ * Copyright Google LLC All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import {ifEnvSupports} from '../test-util';
+
+describe(
+    'queueMicrotask', ifEnvSupports('queueMicrotask', function() {
+      it('callback in the queueMicrotask should be scheduled as microTask in the zone',
+         (done: DoneFn) => {
+           const logs: string[] = [];
+           Zone.current
+               .fork({
+                 name: 'queueMicrotask',
+                 onScheduleTask: (delegate: ZoneDelegate, curr: Zone, target: Zone, task: Task) => {
+                   logs.push(task.type);
+                   logs.push(task.source);
+                   return delegate.scheduleTask(target, task);
+                 }
+               })
+               .run(() => {
+                 queueMicrotask(() => {
+                   expect(logs).toEqual(['microTask', 'queueMicrotask']);
+                   expect(Zone.current.name).toEqual('queueMicrotask');
+                   done();
+                 });
+               });
+         });
+    }));
diff --git a/packages/zone.js/test/browser_entry_point.ts b/packages/zone.js/test/browser_entry_point.ts
@@ -29,3 +29,4 @@ import './mocha-patch.spec';
 import './jasmine-patch.spec';
 import './browser/messageport.spec';
 import './extra/cordova.spec';
+import './browser/queue-microtask.spec';