header-user-agent-async.htm | Explore in Territory

<!DOCTYPE html>
<html>
<head>
    <title>Test that async requests (both OPTIONS preflight and regular) are sent with the User-Agent header</title>
    <script src="/resources/testharness.js"></script>
    <script src="/resources/testharnessreport.js"></script>
    <script src="/common/get-host-info.sub.js"></script>
</head>
<body>
<script type="text/javascript">
  async_test((test) => {
    let xhr = new XMLHttpRequest;
    xhr.open("GET", get_host_info().HTTP_REMOTE_ORIGIN + "/xhr/resources/header-user-agent.py");
    xhr.setRequestHeader("x-test", "foobar");

    xhr.onerror = test.unreached_func("Unexpected error");

    xhr.onload = test.step_func_done(() => {
      assert_equals(xhr.responseText, "PASS");
    });

    xhr.send();
  }, "Async request has User-Agent header");
</script>
</body>
</html>

chromium/third_party/blink/web_tests/external/wpt/xhr/header-user-agent-async.htm