mozilla-release/dom/media/mediasource/test/test_TruncatedDuration_mp4.html

<!DOCTYPE HTML>
<html>
<head>
  <title>MSE: truncating the media seeks to end of media and update buffered range</title>
  <script src="/tests/SimpleTest/SimpleTest.js"></script>
  <script type="text/javascript" src="mediasource.js"></script>
  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
</head>
<body>
<pre id="test">
<script class="testbody" type="text/javascript">

// This test append data to a mediasource and then seek to half the duration
// of the video.
// We then shorten the video to 1/3rd of its original size.
// We ensure that the buffered range immediately reflect the truncation
// and that we've seeked to the new end of the media as per W3C spec and
// video.currentTime got updated.

SimpleTest.waitForExplicitFinish();

const round = n => Math.round(n * 1000) / 1000;

runWithMSE(async (ms, v) => {
  await once(ms, "sourceopen");
  const sb = ms.addSourceBuffer("video/mp4");

  sb.appendBuffer(new Uint8Array(await fetchWithXHR("bipbop/bipbop2s.mp4")));
  await once(sb, "updateend");
  // mp4 metadata states 10s when we only have 1.6s worth of video.
  sb.remove(sb.buffered.end(0), Infinity);
  await once(sb, "updateend");
  ms.duration = sb.buffered.end(0);
  is(v.duration, ms.duration, "current time updated with mediasource duration");
  v.currentTime = v.duration / 2;
  is(v.currentTime, v.duration / 2, "current time was updated");
  ok(v.seeking, "seeking is true");
  await once(v, "seeked");
  const duration = round(v.duration / 3);
  is(sb.updating, false, "sourcebuffer isn't updating");
  sb.remove(duration, Infinity);
  await once(sb, "updateend");
  ms.duration = duration;
  // frames aren't truncated, so duration may be slightly more.
  isfuzzy(v.duration, duration, 1 / 30, "element duration was updated");
  sb.abort(); // this shouldn't abort updating the duration (bug 1130826).
  ok(v.seeking, "seeking is true");
  // test playback position was updated (bug 1130839).
  is(v.currentTime, v.duration, "current time was updated");
  is(sb.buffered.length, 1, "One buffered range");
  // Truncated mediasource duration will cause the video element to seek.
  await once(v, "seeking");
  SimpleTest.finish();
});

</script>
</pre>
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