Bug 1621166 - part4 : add test. r=MeFisto94

Differential Revision: https://phabricator.services.mozilla.com/D67385

--HG--
extra : moz-landing-system : lando

dom/media/mediacontrol/tests/browser.ini

@@ -8,6 +8,7 @@ support-files =
   ../../test/gizmo.mp4
   ../../test/gizmo-noaudio.webm
   ../../test/gizmo-short.mp4
+  !/toolkit/components/pictureinpicture/tests/head.js
   ../../../../toolkit/content/tests/browser/silentAudioTrack.webm
 
 [browser_audio_focus_management.js]
@@ -15,3 +16,4 @@ support-files =
 [browser_media_control_keys_event.js]
 [browser_media_control_non_eligible_media.js]
 [browser_media_control_playback_state.js]
+[browser_media_control_stop_timer.js]

dom/media/mediacontrol/tests/browser_media_control_stop_timer.js

@@ -0,0 +1,80 @@
+/* eslint-disable no-undef */
+
+// Import this in order to use `triggerPictureInPicture()`.
+/* import-globals-from ../../../../../toolkit/components/pictureinpicture/tests/head.js */
+Services.scriptloader.loadSubScript(
+  "chrome://mochitests/content/browser/toolkit/components/pictureinpicture/tests/head.js",
+  this
+);
+
+const PAGE_NON_AUTOPLAY =
+  "https://example.com/browser/dom/media/mediacontrol/tests/file_non_autoplay.html";
+
+const testVideoId = "video";
+
+add_task(async function setupTestingPref() {
+  await SpecialPowers.pushPrefEnv({
+    set: [
+      ["media.mediacontrol.testingevents.enabled", true],
+// As `main-media-controller-playback-changed` is dispatched asynchronously, if
+// we want to receive it after pausing media, we should postpone the time of
+// triggering the stop timer. That value should be changed to 0 after landing
+// bug1620113.
+      ["media.mediacontrol.stopcontrol.timer.ms", 2000],
+    ],
+  });
+});
+
+/**
+ * This test is used to check the stop timer for media element, which would stop
+ * media control for the specific element when the element has been paused over
+ * certain length of time. (That is controlled by the value of the pref
+ * `media.mediacontrol.stopcontrol.timer.ms`) In this test, we set the pref to 0
+ * which means the stop timer would be triggered after the media is paused.
+ * However, if the media is being used in PIP mode, we won't start the stop
+ * timer for it.
+ */
+add_task(async function testStopMediaControlAfterPausingMedia() {
+  info(`open media page`);
+  const tab = await createTabAndLoad(PAGE_NON_AUTOPLAY);
+
+  info(`start media`);
+  await playMedia(tab, testVideoId);
+
+  info(`pause media and the stop timer would stop media control`);
+  await pauseMediaAndMediaControlShouldBeStopped(tab, testVideoId);
+
+  info(`remove tab`);
+  await BrowserTestUtils.removeTab(tab);
+});
+
+add_task(async function testNotToStopMediaControlForPIPVideo() {
+  info(`open media page`);
+  const tab = await createTabAndLoad(PAGE_NON_AUTOPLAY);
+
+  info(`start media`);
+  await playMedia(tab, testVideoId);
+
+  info(`trigger PIP mode`);
+  let pipWin = await triggerPictureInPicture(tab.linkedBrowser, testVideoId);
+
+  info(`pause media and the stop timer would not stop media control`);
+  await pauseMedia(tab, testVideoId);
+
+  info(`pressing 'play' key should start PIP video again`);
+  await generateMediaControlKeyEvent("play");
+  await checkOrWaitUntilMediaStartedPlaying(tab, testVideoId);
+
+  info(`remove tab`);
+  await BrowserTestUtils.removeTab(tab);
+});
+
+/**
+ * The following is helper function.
+ */
+function pauseMediaAndMediaControlShouldBeStopped(tab, testVideoId) {
+  // After pausing media, the stop timer would be triggered and stop the media
+  // control, which would reset the current main media controller.
+  const controllerChangedPromise = waitUntilMainMediaControllerChanged();
+  return Promise.all([pauseMedia(tab, testVideoId), controllerChangedPromise]);
+}

dom/media/mediacontrol/tests/head.js

@@ -18,6 +18,23 @@ async function createTabAndLoad(url, inputWindow = null) {
   return tab;
 }
 
+/**
+ * Returns a promise that resolves when generated media control keys has
+ * triggered the main media controller's corresponding method and changes its
+ * playback state.
+ *
+ * @param {string} event
+ *        The event name of the media control key
+ * @return {Promise}
+ *         Resolve when the main controller receives the media control key event
+ *         and change its playback state.
+ */
+function generateMediaControlKeyEvent(event) {
+  const playbackStateChanged = waitUntilMainMediaControllerPlaybackChanged();
+  ChromeUtils.generateMediaControlKeysTestEvent(event);
+  return playbackStateChanged;
+}
+
 /**
  * Play the specific media and wait until it plays successfully and the main
  * controller has been updated.