chromium/third_party/blink/web_tests/external/wpt/reporting/disconnect.html

<!DOCTYPE HTML>
<meta charset=utf-8>
<title>Reporting: Disconnect</title>
<link rel="author" title="Paul Meyer" href="[email protected]">
<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>
<script>
promise_test(async test => {
    let observer;
    const reportsPromise = new Promise(resolve => {
      observer = new ReportingObserver(resolve);
      observer.observe();
    });

    // The observer should still receive this report even though disconnect()
    // is called immediately afterwards.
    await test_driver.generate_test_report("Test message.")
        .then(() => { observer.disconnect(); });

    const reports = await reportsPromise;
    assert_equals(reports.length, 1);
    assert_equals(reports[0].body.message, "Test message.");
  }, "Disconnect");
</script>