chromium/third_party/blink/web_tests/external/wpt/webaudio/the-audio-api/the-audionode-interface/channel-mode-interp-basic.html

<!DOCTYPE html>
<html>
  <head>
    <title>
      Test Setting of channelCountMode and channelInterpretation
    </title>
    <script src="/resources/testharness.js"></script>
    <script src="/resources/testharnessreport.js"></script>
    <script src="/webaudio/resources/audit-util.js"></script>
    <script src="/webaudio/resources/audit.js"></script>
  </head>
  <body>
    <script id="layout-test-code">
      // Fairly arbitrary sample rate and number of frames, except the number of
      // frames should be more than a few render quantums.
      let sampleRate = 16000;
      let renderFrames = 10 * 128;

      let audit = Audit.createTaskRunner();

      audit.define('interp', (task, should) => {
        let context = new OfflineAudioContext(1, renderFrames, sampleRate);
        let node = context.createGain();

        // Set a new interpretation and verify that it changed.
        node.channelInterpretation = 'discrete';
        let value = node.channelInterpretation;
        should(value, 'node.channelInterpretation').beEqualTo('discrete');
        node.connect(context.destination);

        context.startRendering()
            .then(function(buffer) {
              // After rendering, the value should have been changed.
              should(
                  node.channelInterpretation,
                  'After rendering node.channelInterpretation')
                  .beEqualTo('discrete');
            })
            .then(() => task.done());
      });

      audit.define('mode', (task, should) => {
        let context = new OfflineAudioContext(1, renderFrames, sampleRate);
        let node = context.createGain();

        // Set a new mode and verify that it changed.
        node.channelCountMode = 'explicit';
        let value = node.channelCountMode;
        should(value, 'node.channelCountMode').beEqualTo('explicit');
        node.connect(context.destination);

        context.startRendering()
            .then(function(buffer) {
              // After rendering, the value should have been changed.
              should(
                  node.channelCountMode,
                  'After rendering node.channelCountMode')
                  .beEqualTo('explicit');
            })
            .then(() => task.done());
      });

      audit.run();
    </script>
  </body>
</html>