context-time-monotonic-on-setsinkid.https.html

Enable keyboard shortcuts

This test has a WPT meta file that expects 1 subtest issues.
This WPT test may be referenced by the following Test IDs:
- /webaudio/the-audio-api/the-audiocontext-interface/context-time-monotonic-on-setsinkid.https.html - WPT Dashboard Interop Dashboard

<!DOCTYPE html>

<html>

<head>

<title>currentTime and getOutputTimestamp().contextTime after setSinkId</title>

<meta name="flags" content="--use-fake-device-for-media-stream">

<script src="/resources/testharness.js"></script>

<script src="/resources/testharnessreport.js"></script>

</head>

<body>

<script>

promise_test(async t => {

  // A timeout for waiting for the audio context to transition to a new state.

  const TRANSITION_TIMEOUT = 250;

  const context = new AudioContext();

  t.add_cleanup(() => context.close());

  await context.resume();

  // Let it run for a bit to ensure time values are advancing.

  await new Promise(resolve => t.step_timeout(resolve, TRANSITION_TIMEOUT));

  const initialCurrentTime = context.currentTime;

  const initialContextTime = context.getOutputTimestamp().contextTime;

  assert_true(

      initialCurrentTime > 0,

      'Pre-check: currentTime should be > 0 after running for a while');

  assert_true(

      initialContextTime > 0,

      'Pre-check: contextTime should be > 0 after running for a while');

  const devices = await navigator.mediaDevices.enumerateDevices();

  const audioOutputDevices = devices.filter(d => d.kind === 'audiooutput');

  if (audioOutputDevices.length < 2) {

    // This test requires at least two audio output devices.

    assert_unreached(

        'Not enough audio output devices to run this test. Need at least 2.');

  // Find a device that is not the current one.

  const newDeviceId =

      audioOutputDevices.find(d => d.deviceId !== context.sinkId)?.deviceId;

  if (!newDeviceId) {

    assert_unreached('Could not find a different device to switch to.');

  // Capture timestamps just before the switch.

  const timeBeforeSetSinkId = context.currentTime;

  const contextTimeBeforeSetSinkId = context.getOutputTimestamp().contextTime;

  await context.setSinkId(newDeviceId);

  // Capture timestamps immediately after the switch.

  const timeAfterSetSinkId = context.currentTime;

  const contextTimeAfterSetSinkId = context.getOutputTimestamp().contextTime;

  // The time should not go backwards for either currentTime or contextTime.

  assert_true(

      timeAfterSetSinkId >= timeBeforeSetSinkId,

      `currentTime should not go backwards after setSinkId. Before: ${

          timeBeforeSetSinkId}, after: ${timeAfterSetSinkId}`);

  assert_true(

      contextTimeAfterSetSinkId >= contextTimeBeforeSetSinkId,

      `contextTime should not go backwards after setSinkId. Before: ${

          contextTimeBeforeSetSinkId}, after: ${contextTimeAfterSetSinkId}`);

  // The time should not jump too far ahead. A small delta is expected for the

  // device change while the context is running.

  assert_true(

      timeAfterSetSinkId - timeBeforeSetSinkId < 1,

      `setSinkId took too long or currentTime jumped. Before: ${

          timeBeforeSetSinkId}, after: ${timeAfterSetSinkId}`);

  // Let it run for a bit more to ensure it's still advancing.

  await new Promise(resolve => t.step_timeout(resolve, TRANSITION_TIMEOUT));

  const finalCurrentTime = context.currentTime;

  const finalContextTime = context.getOutputTimestamp().contextTime;

  assert_true(

      finalCurrentTime > timeAfterSetSinkId,

      `currentTime should increase after setSinkId. After switch: ${

          timeAfterSetSinkId}, final: ${finalCurrentTime}`);

  assert_true(

      finalContextTime > contextTimeAfterSetSinkId,

      `contextTime should increase after setSinkId. After switch: ${

          contextTimeAfterSetSinkId}, final: ${finalContextTime}`);

}, 'currentTime and getOutputTimestamp().contextTime should not reset after ' +

       'setSinkId');

</script>

</body>

</html>