audioparam-rate-change-357391257.html

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<head>
  <meta name="timeout" content="long"/>
  <title>
    AudioParam automateRate property change - crbug.com/357391257
  </title>
  <script src="../../resources/testharness.js"></script>
  <script src="../../resources/testharnessreport.js"></script>
</head>
<body>
  <script>
    const t = async_test('audio-param-rate-change-357391257');

    // The problematic value used in the reproduction code.
    const testValue = 5;

    // Number of iterations for triggering the issue. A high value can strain
    // testing resources. Empirically determined: the reported repro case was
    // aboe to crash in 3 iterations on average.
    const maxIteration = 3;

    // The original repro only has setValueAtTime() but the fix/test covers
    // all methods.
    const subtestTypes = [
      'setValueAtTime',
      'linearRampToValueAtTime',
      'exponentialRampToValueAtTime',
      'linearRampToValueAtTime',
      'setTargetAtTime',
      'setValueCurveAtTime'
    ];

    let subtestsCompleted = 0;

    const runTest = (iteration, subtestType) => {
      const context = new AudioContext({sampleRate: 768000});
      const scriptNode = context.createScriptProcessor();
      const delayNode = context.createDelay(1);

      scriptNode.onaudioprocess = () => {
        delayNode.delayTime.automationRate = 'k-rate';
        delayNode.delayTime.automationRate = 'a-rate';
      };
      delayNode.delayTime.linearRampToValueAtTime(1, 2);
      scriptNode.connect(delayNode).connect(context.destination);

      switch (subtestTypes[subtestType]) {
        case 'setValueAtTime':
          delayNode.delayTime.setValueAtTime(testValue, context.currentTime);
          break;
        case 'linearRampToValueAtTime':
          delayNode.delayTime.linearRampToValueAtTime(
              testValue, context.currentTime);
          break;
        case 'exponentialRampToValueAtTime':
          delayNode.delayTime.exponentialRampToValueAtTime(
              testValue, context.currentTime);
          break;
        case 'setTargetAtTime':
          delayNode.delayTime.setTargetAtTime(
              testValue, context.currentTime, 0);
          break;
        case 'setValueCurveAtTime':
          const curve = new Float32Array(2);
          curve[0] = testValue;
          curve[1] = 0;
          // To avoid the schedule overlap with setValueAtTime() above, start
          // the automation at 2.5s.
          delayNode.delayTime.setValueCurveAtTime(curve, 2.5, 1);
          break;
        defaut:
          assert_unreached('invalid method test type');
      }

      if (iteration < maxIteration) {
        setTimeout(() => runTest(iteration + 1, subtestType), 100);
      } else {
        if (++subtestsCompleted === subtestTypes.length) {
          context.close();
          t.done();
        }
      }
    };

    window.addEventListener('load', t.step_func(() => {
      subtestTypes.forEach((_, subtestType) => runTest(0, subtestType));
    }));
  </script>
</body>
</html>
chromium/third_party/blink/web_tests/webaudio/AudioParam/audioparam-rate-change-357391257.html
