webaudio/the-audio-api/the-delaynode-interface/delaynode-maxdelaylimit.html

<!DOCTYPE html>
<html>
  <head>
    <title>
      delaynode-maxdelaylimit.html
    </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/delay-testing.js"></script>
  </head>
  <body>
    <script id="layout-test-code">
      let audit = Audit.createTaskRunner();

      audit.define(
          {
            label: 'test',
            description:
                'Tests attribute and maximum allowed delay of DelayNode'
          },
          function(task, should) {

            // Create offline audio context.
            let context = new OfflineAudioContext(
                1, sampleRate * renderLengthSeconds, sampleRate);
            let toneBuffer = createToneBuffer(
                context, 20, 20 * toneLengthSeconds, sampleRate);  // 20Hz tone

            let bufferSource = context.createBufferSource();
            bufferSource.buffer = toneBuffer;

            window.context = context;
            should(() => context.createDelay(180),
                   'Setting Delay length to 180 seconds or more')
                .throw(DOMException, 'NotSupportedError');
            should(() => context.createDelay(0),
                   'Setting Delay length to 0 seconds')
                .throw(DOMException, 'NotSupportedError');
            should(() => context.createDelay(-1),
                   'Setting Delay length to negative')
                .throw(DOMException, 'NotSupportedError');
            should(() => context.createDelay(NaN),
                   'Setting Delay length to NaN')
                .throw(TypeError);

            let delay = context.createDelay(179);
            delay.delayTime.value = delayTimeSeconds;
            window.delay = delay;
            should(
                delay.delayTime.value,
                'delay.delayTime.value = ' + delayTimeSeconds)
                .beEqualTo(delayTimeSeconds);

            bufferSource.connect(delay);
            delay.connect(context.destination);
            bufferSource.start(0);

            context.startRendering()
                .then(buffer => checkDelayedResult(buffer, toneBuffer, should))
                .then(() => task.done());
          });

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