| <!DOCTYPE html> | 
 | <title>window.requestIdleCallback exists</title> | 
 | <link rel="author" title="Ross McIlroy" href="mailto:rmcilroy@chromium.org" /> | 
 | <script src="/resources/testharness.js"></script> | 
 | <script src="/resources/testharnessreport.js"></script> | 
 | <script> | 
 | // The window.requestIdleCallback function is used to request callbacks during browser-defined idle time. | 
 | test(function() { | 
 |  assert_equals(typeof window.requestIdleCallback, "function"); | 
 | }, "window.requestIdleCallback is defined"); | 
 |  | 
 | // The window.cancelIdleCallback function is used to cancel callbacks scheduled via requestIdleCallback. | 
 | test(function() { | 
 |  assert_equals(typeof window.cancelIdleCallback, "function"); | 
 | }, "window.cancelIdleCallback is defined"); | 
 |  | 
 | // The requestIdleCallback method MUST return a long | 
 | test(function() { | 
 |  assert_equals(typeof window.requestIdleCallback(function() {}), "number"); | 
 | }, "window.requestIdleCallback() returns a number"); | 
 |  | 
 | // The cancelIdleCallback method MUST return void | 
 | test(function() { | 
 |  assert_equals(typeof window.cancelIdleCallback(1), "undefined"); | 
 | }, "window.cancelIdleCallback() returns undefined"); | 
 |  | 
 | async_test(function() { | 
 |  // Check whether requestIdleCallback schedules a callback which gets executed | 
 |  // and the deadline argument is passed correctly. | 
 |  requestIdleCallback(this.step_func_done(function(deadline) { | 
 |  assert_equals(arguments.length, 1, "Only one argument should be passed to callback."); | 
 |  assert_class_string(deadline, "IdleDeadline"); | 
 |  assert_equals(typeof deadline.timeRemaining, "function", "IdleDeadline.timeRemaining MUST be a function which returns the time remaining in milliseconds"); | 
 |  assert_equals(typeof deadline.timeRemaining(), "number", "IdleDeadline.timeRemaining MUST return a double of the time remaining in milliseconds"); | 
 |  assert_true(deadline.timeRemaining() <= 50, "IdleDeadline.timeRemaining() MUST be less than or equal to 50ms in the future."); | 
 |  assert_equals(typeof deadline.didTimeout, "boolean", "IdleDeadline.didTimeout MUST be a boolean"); | 
 |  assert_false(deadline.didTimeout, "IdleDeadline.didTimeout MUST be false if requestIdleCallback wasn't scheduled due to a timeout"); | 
 |  })); | 
 | }, 'requestIdleCallback schedules callbacks'); | 
 |  | 
 | async_test(function() { | 
 |  // Check whether requestIdleCallback schedules a callback which gets executed | 
 |  // and the deadline argument is passed correctly. | 
 |  var handle = requestIdleCallback(this.step_func(function(deadline) { | 
 |  assert_unreached("callback should not be called if canceled with cancelIdleCallback"); | 
 |  })); | 
 |  cancelIdleCallback(handle); | 
 |  step_timeout(this.step_func_done(), 200); | 
 | }, 'cancelIdleCallback cancels callbacks'); | 
 |  | 
 | </script> | 
 | <h1>Basic requestIdleCallback Tests</h1> | 
 | <div id="log"></div> |