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<!DOCTYPE html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/speculation-rules/prerender/resources/utils.js"></script>
<div id="target"></div>
<iframe id="i" srcdoc="<html><body>Hello</body></html>"></iframe>
<script>
assert_true(document.prerendering);
const params = new URLSearchParams(location.search);
const uid = params.get('uid');
i.contentWindow.onbeforeunload = function(e) {
// Call preventDefault() or set `returnValue` to trigger the prompt
// on beforeunload event.
// The prompt actually doesn't show up in a prerendered page and
// unload proceeds.
e.preventDefault();
e.returnValue = 'You have a return value.';
}
async function navigateWindowLocation() {
const bc = new PrerenderChannel('inner-channel', uid);
const promise = new Promise(resolve => {
bc.addEventListener('message', e => {
resolve(e.data);
bc.close();
}, {
once: true
});
});
i.contentWindow.location.href = `prompt-by-before-unload-inner-frame.html?uid=${uid}`;
return promise;
}
async function asyncPromptOnBeforeUnload() {
const bc = new PrerenderChannel('prerender-channel', uid);
try {
const result = await navigateWindowLocation();
if (result == 'a new page is loaded')
bc.postMessage('unloaded without the prompt by beforeunload.');
else
bc.postMessage('unexpected result.');
} catch (err) {
bc.postMessage(err);
} finally {
bc.close();
}
}
asyncPromptOnBeforeUnload();
</script>