2 files changed, 9 insertions, 80 deletions

diff --git a/demo/src/task-scheduler.spec.ts b/demo/src/task-scheduler.spec.ts
deleted file mode 100644
index 9b3eeff..0000000
--- a/demo/src/task-scheduler.spec.ts
+++ /dev/null
@@ -1,66 +0,0 @@
-/**
- * remove-me @jest-environment jsdom
- */
-/// <reference lib="dom" />
-
-import { MicroTaskScheduler } from './task-scheduler';
-
-/*
- * We're skipping this test due to JSDOM issue:
- * https://github.com/jsdom/jsdom/issues/2961
- *
- * It should pass on Node >= 12.0, but since the core library
- * is expected to run on Node >= 10.0, and this test only applies
- * to the demo project, it's better disabling it for now than
- * getting false negatives.
- *
- * When this test is eventually re-enabled, don't forget to remove
- * the `remove-me` text at the top of this file to re-enable the
- * loading of jsdom.
- */
-// eslint-disable-next-line jest/no-disabled-tests
-describe.skip('task-scheduler', () => {
-  let taskScheduler: MicroTaskScheduler;
-  let task: jest.Mock;
-
-  beforeEach(() => {
-    taskScheduler = new MicroTaskScheduler();
-    task = jest.fn();
-  });
-
-  it('should execute task', async () => {
-    taskScheduler.start();
-    taskScheduler.postTask(task);
-    await new Promise((resolve) => setTimeout(resolve, 0));
-    expect(task).toHaveBeenCalledTimes(1);
-  });
-
-  it('should execute task twice when posted twice', async () => {
-    taskScheduler.start();
-    taskScheduler.postTask(task);
-    taskScheduler.postTask(task);
-    await new Promise((resolve) => setTimeout(resolve, 0));
-    expect(task).toHaveBeenCalledTimes(2);
-  });
-
-  it('should not execute task when not started', async () => {
-    taskScheduler.postTask(task);
-    await new Promise((resolve) => setTimeout(resolve, 0));
-    expect(task).not.toHaveBeenCalled();
-  });
-
-  it('should not execute task when stopped', async () => {
-    taskScheduler.start();
-    taskScheduler.stop();
-    taskScheduler.postTask(task);
-    await new Promise((resolve) => setTimeout(resolve, 0));
-    expect(task).not.toHaveBeenCalled();
-  });
-
-  it('should not register listener twice', async () => {
-    const addEventListenerSpy = jest.spyOn(window, 'addEventListener');
-    taskScheduler.start();
-    taskScheduler.start();
-    expect(addEventListenerSpy).toHaveBeenCalledTimes(1);
-  });
-});
diff --git a/demo/src/task-scheduler.ts b/demo/src/task-scheduler.ts
index 5364d92..46413ef 100644
--- a/demo/src/task-scheduler.ts
+++ b/demo/src/task-scheduler.ts
@@ -1,39 +1,34 @@
-// Faster setTimeout(fn, 0) implementation using postMessage API
-// Based on https://dbaron.org/log/20100309-faster-timeouts
 export type IMicroTaskCallback = () => void;
 
 export class MicroTaskScheduler {
-  readonly messageName = 'zero-timeout-message';
-
+  private readonly channel = new MessageChannel();
   private executionQueue: Array<IMicroTaskCallback> = [];
   private stopped = true;
 
   start() {
     if (this.stopped) {
       this.stopped = false;
-      window.addEventListener('message', this.handleMessage, true);
+      this.channel.port2.onmessage = this.handleMessage;
     }
   }
 
   stop() {
     this.stopped = true;
-    window.removeEventListener('message', this.handleMessage, true);
+    this.executionQueue.splice(0, this.executionQueue.length);
+    this.channel.port2.onmessage = null;
   }
 
   postTask(fn: IMicroTaskCallback) {
     if (!this.stopped) {
       this.executionQueue.push(fn);
-      window.postMessage(this.messageName, '*');
+      this.channel.port1.postMessage(null);
     }
   }
 
-  private handleMessage = (event: MessageEvent) => {
-    if (event.data === this.messageName) {
-      event.stopPropagation();
-      const executeJob = this.executionQueue.shift();
-      if (executeJob !== undefined) {
-        executeJob();
-      }
+  private handleMessage = () => {
+    const executeJob = this.executionQueue.shift();
+    if (executeJob !== undefined) {
+      executeJob();
     }
   };
 }