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<!DOCTYPE HTML>
<html>
<!--
https://bugzilla.mozilla.org/show_bug.cgi?id=1462891
-->
<head>
<title>Test for Bug 1462891</title>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<script src="/tests/SimpleTest/SimpleTest.js"></script>
</head>
<body>
<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1462891">Mozilla Bug 1462891 - Navigation Timing API</a>
<div id="content">
</div>
<pre id="test">
<script class="testbody" type="text/javascript">
var index = 0;
let isRounded = (x, shouldRound, expectedPrecision) => {
if (!shouldRound)
return true;
let rounded = (Math.floor(x / expectedPrecision) * expectedPrecision);
// First we do the perfectly normal check that should work just fine
if (rounded === x || x === 0)
return true;
// When we're diving by non-whole numbers, we may not get perfect
// multiplication/division because of floating points.
// When dealing with ms since epoch, a double's precision is on the order
// of 1/5 of a microsecond, so we use a value a little higher than that as
// our epsilon.
// To be clear, this error is introduced in our re-calculation of 'rounded'
// above in JavaScript.
if (Math.abs(rounded - x + expectedPrecision) < .0005) {
return true;
} else if (Math.abs(rounded - x) < .0005) {
return true;
}
// Then we handle the case where you're sub-millisecond and the timer is not
// We check that the timer is not sub-millisecond by assuming it is not if it
// returns an even number of milliseconds
if (expectedPrecision < 1 && Math.round(x) == x) {
if (Math.round(rounded) == x) {
return true;
}
}
ok(false, "Looming Test Failure, Additional Debugging Info: Expected Precision: " + expectedPrecision + " Measured Value: " + x +
" Rounded Vaue: " + rounded + " Fuzzy1: " + Math.abs(rounded - x + expectedPrecision) +
" Fuzzy 2: " + Math.abs(rounded - x));
return false;
};
var metrics = [
"unloadEventStart",
"unloadEventEnd",
"domInteractive",
"domContentLoadedEventStart",
"domContentLoadedEventEnd",
"domComplete",
"loadEventStart",
"loadEventEnd"
];
async function runTests(resistFingerprinting, reduceTimerPrecision, expectedPrecision) {
await SpecialPowers.pushPrefEnv({
"set": [["privacy.resistFingerprinting", resistFingerprinting],
["privacy.reduceTimerPrecision", reduceTimerPrecision],
["privacy.resistFingerprinting.reduceTimerPrecision.microseconds", expectedPrecision * 1000]
]});
var entries = performance.getEntriesByType("navigation");
is(entries.length, 1, "Checking PerformanceNavigationEntry count");
for (let i=0; i<entries.length; i++) {
for (let j=0; j<metrics.length; j++) {
ok(isRounded(entries[i][metrics[j]], reduceTimerPrecision, expectedPrecision),
"Testing " + metrics[j] + " with value " + entries[i][metrics[j]] +
" with resistFingerprinting " + resistFingerprinting + " reduceTimerPrecision " +
reduceTimerPrecision + " precision " + expectedPrecision);
}
}
}
async function startTests() {
await runTests(false, false, 2);
await runTests(true, false, 2);
await runTests(true, true, 2);
await runTests(false, true, 1000);
await runTests(false, true, 133);
await runTests(false, true, 13);
await runTests(false, true, 2);
await runTests(false, true, 1);
SimpleTest.finish();
}
SimpleTest.waitForExplicitFinish();
addLoadEvent(startTests);
</script>
</pre>
</body>
</html>
|
