chromium/third_party/blink/web_tests/external/wpt/webaudio/the-audio-api/the-audiobuffer-interface/audiobuffer-getChannelData.html

<!DOCTYPE html>
<html>
  <head>
    <title>
      Test AudioBuffer.getChannelData() Returns the Same Object
    </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>
    <script src="/webaudio/resources/audioparam-testing.js"></script>
  </head>
  <body>
    <script id="layout-test-code">
      let sampleRate = 48000;
      let renderDuration = 0.5;

      let audit = Audit.createTaskRunner();

      audit.define('buffer-eq', (task, should) => {
        // Verify that successive calls to getChannelData return the same
        // buffer.
        let context = new AudioContext();
        let channelCount = 2;
        let frameLength = 1000;
        let buffer =
            context.createBuffer(channelCount, frameLength, context.sampleRate);

        for (let c = 0; c < channelCount; ++c) {
          let a = buffer.getChannelData(c);
          let b = buffer.getChannelData(c);

          let message = 'buffer.getChannelData(' + c + ')';
          should(a === b, message + ' === ' + message).beEqualTo(true);
        }

        task.done();
      });

      audit.define('buffer-not-eq', (task, should) => {
        let context = new AudioContext();
        let channelCount = 2;
        let frameLength = 1000;
        let buffer1 =
            context.createBuffer(channelCount, frameLength, context.sampleRate);
        let buffer2 =
            context.createBuffer(channelCount, frameLength, context.sampleRate);
        let success = true;

        for (let c = 0; c < channelCount; ++c) {
          let a = buffer1.getChannelData(c);
          let b = buffer2.getChannelData(c);

          let message = 'getChannelData(' + c + ')';
          should(a === b, 'buffer1.' + message + ' === buffer2.' + message)
                  .beEqualTo(false) &&
              success;
        }

        task.done();
      });

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