<html>
<head>
<title>Service Worker Fetch Event</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
</head>
<body>
<iframe id='myframe'></iframe>
<script>
promise_test(async () => {
    const promise = new Promise(resolve => window.resolveCallback = resolve);
    myframe.contentDocument.write(`
    <body>
        <script>
            navigator.serviceWorker.register('about-blank-iframe-worker.js').then(registration => {
                window.worker = registration.active ? registration.active : registration.installing;
                parent.resolveCallback();
            });
        </${'script'}>
    </body>`);
    return promise;
}, "setup");

promise_test(async () => {
    const promise = new Promise((resolve, reject) => {
        navigator.serviceWorker.addEventListener("message", (event) => {
            resolve(event.data);
        });
        setTimeout(() => reject("No response message from service worker"), 5000);
    });

    myframe.contentWindow.worker.postMessage("hello");
    assert_equals(await promise, "hello");
}, "post messaging from an iframe");

promise_test(async () => {
    const registrations = await navigator.serviceWorker.getRegistrations();
    for (let registration of registrations)
        await registration.unregister();
    myframe.remove();
}, "remove iframe");
</script>
</body>
</html>