зеркало из https://github.com/mozilla/gecko-dev.git
133 строки
4.0 KiB
HTML
133 строки
4.0 KiB
HTML
<!DOCTYPE HTML>
|
|
<html>
|
|
<!--
|
|
https://bugzilla.mozilla.org/show_bug.cgi?id=1378586
|
|
-->
|
|
<head>
|
|
<meta charset="utf-8">
|
|
<title>Test for Bug 1378586</title>
|
|
<script src="/tests/SimpleTest/SimpleTest.js"></script>
|
|
<link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
|
|
</head>
|
|
<body>
|
|
<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1378586">Mozilla Bug 1378586</a>
|
|
|
|
<script>
|
|
SimpleTest.waitForExplicitFinish();
|
|
|
|
// We need to clear our nesting level periodically. We do this by firing
|
|
// a postMessage() to get a runnable on the event loop without any setTimeout()
|
|
// nesting.
|
|
function clearNestingLevel() {
|
|
return new Promise(resolve => {
|
|
window.addEventListener('message', function onMessage() {
|
|
window.removeEventListener('message', onMessage);
|
|
resolve();
|
|
});
|
|
postMessage('done', '*');
|
|
});
|
|
}
|
|
|
|
function delayByTimeoutChain(iterations) {
|
|
return new Promise(resolve => {
|
|
let count = 0;
|
|
function tick() {
|
|
count += 1;
|
|
if (count >= iterations) {
|
|
resolve();
|
|
return;
|
|
}
|
|
setTimeout(tick, 0);
|
|
}
|
|
setTimeout(tick, 0);
|
|
});
|
|
}
|
|
|
|
function delayByInterval(iterations) {
|
|
return new Promise(resolve => {
|
|
let count = 0;
|
|
function tick() {
|
|
count += 1;
|
|
if (count >= iterations) {
|
|
resolve();
|
|
return;
|
|
}
|
|
}
|
|
setInterval(tick, 0);
|
|
});
|
|
}
|
|
|
|
// Use a very long clamp delay to make it easier to measure the change
|
|
// in automation. Some of our test servers are very slow and noisy.
|
|
const clampDelayMS = 10000;
|
|
|
|
// We expect that we will clamp on the 5th callback. This should
|
|
// be the same for both setTimeout() chains and setInterval().
|
|
const expectedClampIteration = 5;
|
|
|
|
async function runTests() {
|
|
// Things like pushPrefEnv() can use setTimeout() internally which may give
|
|
// us a nesting level. Clear the nesting level to start so this doesn't
|
|
// confuse the test.
|
|
await clearNestingLevel();
|
|
|
|
// Verify a setTimeout() chain clamps correctly
|
|
let start = performance.now();
|
|
await delayByTimeoutChain(expectedClampIteration);
|
|
let stop = performance.now();
|
|
let delta = stop - start;
|
|
|
|
ok(delta >= clampDelayMS, "setTimeout() chain clamped: " + stop + " - " + start + " = " + delta);
|
|
ok(delta < (2*clampDelayMS), "setTimeout() chain did not clamp twice");
|
|
|
|
await clearNestingLevel();
|
|
|
|
// Verify setInterval() clamps correctly
|
|
start = performance.now();
|
|
await delayByInterval(expectedClampIteration);
|
|
stop = performance.now();
|
|
delta = stop - start;
|
|
|
|
ok(delta >= clampDelayMS, "setInterval() clamped: " + stop + " - " + start + " = " + delta);
|
|
ok(delta < (2*clampDelayMS), "setInterval() did not clamp twice");
|
|
|
|
await clearNestingLevel();
|
|
|
|
// Verfy a setTimeout() chain will continue to clamp past the first
|
|
// expected iteration.
|
|
const expectedDelay = (1 + expectedClampIteration) * clampDelayMS;
|
|
|
|
start = performance.now();
|
|
await delayByTimeoutChain(2 * expectedClampIteration);
|
|
stop = performance.now();
|
|
delta = stop - start;
|
|
|
|
ok(delta >= expectedDelay, "setTimeout() chain continued to clamp: " + stop + " - " + start + " = " + delta);
|
|
|
|
await clearNestingLevel();
|
|
|
|
// Verfy setInterval() will continue to clamp past the first expected
|
|
// iteration.
|
|
start = performance.now();
|
|
await delayByTimeoutChain(2 * expectedClampIteration);
|
|
stop = performance.now();
|
|
delta = stop - start;
|
|
|
|
ok(delta >= expectedDelay, "setInterval() continued to clamp: " + stop + " - " + start + " = " + delta);
|
|
|
|
SimpleTest.finish();
|
|
}
|
|
|
|
// It appears that it's possible to get unlucky with time jittering and fail this test.
|
|
// If start is jittered upwards, everything executes very quickly, and delta has
|
|
// a very high midpoint, we may have taken between 10 and 10.002 seconds to execute; but
|
|
// it will appear to be 9.998. Turn off jitter (and add logging) to test this.
|
|
SpecialPowers.pushPrefEnv({ 'set': [
|
|
["dom.min_timeout_value", clampDelayMS],
|
|
["privacy.resistFingerprinting.reduceTimerPrecision.jitter", false],
|
|
]}, runTests);
|
|
</script>
|
|
|
|
</body>
|
|
</html>
|