<!doctype html>
<html>
<head>
<title>XMLHttpRequest: setRequestHeader() before open()</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<link rel="help" href="https://xhr.spec.whatwg.org/#the-setrequestheader()-method" data-tested-assertations="following::ol/li[1]" />
</head>
<body>
<div id="log"></div>
<script>
test(function() {
var client = new XMLHttpRequest()
assert_throws("InvalidStateError", function() { client.setRequestHeader("x-test", "test") })
}, 'setRequestHeader invoked before open()')
</script>
</body>
</html>