chromium/third_party/blink/web_tests/wpt_internal/webmidi/loopback-receive.https.html

<!DOCTYPE html>
<html>
<head>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/resources/testdriver.js"></script>
<script src="/resources/testdriver-vendor.js"></script>
</head>
<body>
<script type="module">
import {MockMIDIService} from './resources/mock-midiservice.js';

const mock = new MockMIDIService();

const testData = [
    // Complete messages.
    [0x80, 0x00, 0x00],
    [0x90, 0x00, 0x00],
    [0xa0, 0x00, 0x00],
    [0xb0, 0x00, 0x00],
    [0xc0, 0x00],
    [0xd0, 0x00],
    [0xe0, 0x00, 0x00],

    // Real-Time messages.
    [0xf8],
    [0xfa],
    [0xfb],
    [0xfc],
    [0xfe],
    [0xff],

    // Sysex messages.
    [0xf0, 0x00, 0x01, 0x02, 0x03, 0xf7],
    [0xf0, 0xf8, 0xf7],
];

let receiveCount;

function verifyData(e) {
    assert_array_equals(e.data, testData[receiveCount]);
    receiveCount++;
    if (receiveCount == testData.length) {
      // Clear the event handler in case the input object isn't GC'ed, to
      // prevent it from being called on the second run of test().
      e.target.onmidimessage = undefined;
      e.target.removeEventListener('midimessage', verifyData);
      e.target.resolve();
    }
}

function test(useAddEventListener) {
    receiveCount = 0;
    return new Promise(function(resolve, reject) {
        navigator.requestMIDIAccess({sysex: true}).then(function (a) {
            var input = a.inputs.values().next().value;
            input.resolve = resolve;
            input.reject = reject;
            if (useAddEventListener) {
                input.addEventListener('midimessage', verifyData);
            } else {
                input.onmidimessage = verifyData;
            }
            var output = a.outputs.values().next().value;
            for (var i = 0; i < testData.length; ++i)
                output.send(testData[i]);
        }, function () {
            testFailed("requestMIDIAccess() return an error.");
            reject();
        });
    });
}

promise_test(async _ => {
  await test_driver.set_permission({name: 'midi', sysex: true}, 'granted');
  await test(false);
  await test(true);
}, 'midimessage event handling works as expected');

</script>
</body>
</html>