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<!DOCTYPE html>
<!-- This Source Code Form is subject to the terms of the Mozilla Public
- License, v. 2.0. If a copy of the MPL was not distributed with this
<html>
<head>
<meta charset="utf-8"/>
<title></title>
</head>
<body>
<script>
"use strict";
// This file is used to test the injection of performance profiles into a front-end,
// specifically the mechanism used to inject into profiler.firefox.com. Rather
// than using some kind of complicated message passing scheme to talk to the test
// harness, modify the title of the page. The tests can easily read the window
// title to see if things worked as expected.
// The following are the titles used to communicate the page's state to the tests.
// Keep these in sync with any tests that read them.
const initialTitle = "Waiting on the profile";
const successTitle = "Profile received";
const errorTitle = "Error"
document.title = initialTitle;
// A function which requests the profile from the browser using the GET_PROFILE
// WebChannel message.
function getProfile() {
return new Promise((resolve, reject) => {
const requestId = 0;
function listener(event) {
window.removeEventListener(
"WebChannelMessageToContent",
listener,
true
);
const { id, message } = event.detail;
if (id !== "profiler.firefox.com" ||
!message ||
typeof message !== "object"
) {
console.error(message);
reject(new Error("A malformed WebChannel event was received."));
return;
}
if (!message.type) {
console.error(message);
reject(new Error("The WebChannel event indicates an error."));
return;
}
if (message.requestId === requestId) {
if (message.type === "SUCCESS_RESPONSE") {
resolve(message.response);
} else {
reject(new Error(message.error));
}
}
}
window.addEventListener("WebChannelMessageToContent", listener, true);
window.dispatchEvent(
new CustomEvent("WebChannelMessageToChrome", {
detail: JSON.stringify({
id: "profiler.firefox.com",
message: { type: "GET_PROFILE", requestId },
}),
})
);
})
}
async function runTest() {
try {
// Get the profile.
const profile = await getProfile();
// Check that the profile is somewhat reasonable. It should be a gzipped
// profile, so we can only lightly check some properties about it, and check
// that it is an ArrayBuffer.
//
// After the check, modify the title of the document, so the tab title gets
// updated. This is an easy way to pass a message to the test script.
if (
profile &&
typeof profile === 'object' &&
(
// The popup injects the compressed profile as an ArrayBuffer.
(profile instanceof ArrayBuffer) ||
// DevTools injects the profile as just the plain object, although
// maybe in the future it could also do it as a compressed profile
Object.keys(profile).includes("threads")
)
) {
// The profile looks good!
document.title = successTitle;
} else {
// The profile doesn't look right, surface the error to the terminal.
dump('The gecko profile was malformed in fake-frontend.html\n');
dump(`Profile: ${JSON.stringify(profile)}\n`);
// Also to the web console.
console.error(profile);
// Report the error to the tab title.
document.title = errorTitle;
}
} catch (error) {
// Catch any error and notify the test.
document.title = errorTitle;
dump('An error was caught in fake-frontend.html\n');
dump(`${error}\n`);
}
}
runTest();
</script>
</body>
</html>