chromium/third_party/blink/web_tests/external/wpt/remote-playback/prompt-and-watch-availability-no-device-manual.html

<!DOCTYPE html>
<html>
  <title>
    Test that watchAvailability() runs the callback with false when there is no device for the user to select
  </title>
  <script src="/resources/testharness.js"></script>
  <script src="/resources/testharnessreport.js"></script>
  <script src="/common/media.js"></script>
  <script>
    setup({ explicit_timeout: true });
  </script>
  <body>
    <div id="prep">
      <p>Please make sure <b>no device is available</b> for remote playback.</p>
      <button id="prompt-button-prep">Show devices</button>
      <button id="start-button">Start test</button>
    </div>
    <div id="pick-device" style="display: none">
      <p>
        Click the button below to prompt for a remote playback device and
        cancel!
      </p>
      <button id="prompt-button">Pick device</button>
    </div>
  </body>
  <script src="./prepare-device.js"></script>
  <script>
    let v = document.createElement("video");
    v.src = getVideoURI("/media/movie_5");

    async_test(t => {
      let deviceAvailable = false;
      let button = document.getElementById("prompt-button");
      button.onclick = function () {
        v.remote
          .watchAvailability(t.step_func(avail => (deviceAvailable = avail)))
          .then(
            t.step_func(() => {
              assert_false(deviceAvailable);
              promise_rejects_dom(t, 'NotFoundError', v.remote.prompt())
              .then(() => {
                t.done();
              });
            }),
            t.unreached_func()
          );
      };
    }, "Test that watchAvailability() runs the callback with false when there is no device for the user to select.");
  </script>
</html>