<html>
<!--
https://bugzilla.mozilla.org/show_bug.cgi?id=1268195
-->
<head>
<meta charset="utf-8">
<title>Test for Bug 1268195</title>
<script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
<link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
<style>
html, body {
margin: 0;
padding: 0;
}
.noscroll {
overflow: hidden;
height: 100%;
}
/* Toggling this on and off triggers a frame reconstruction on the <body> */
html.reconstruct-body::before {
top: 0;
content: '';
display: block;
height: 2px;
position: absolute;
width: 100%;
z-index: 99;
}
</style>
<script type="application/javascript">
SimpleTest.waitForExplicitFinish();
function run() {
// Make sure we have the right scroll element
SimpleTest.is(document.body.scrollTopMax > 0, true, "Body is the scrolling element");
// Scroll to the bottom
document.body.scrollTop = document.body.scrollTopMax;
SimpleTest.is(document.body.scrollTop > 0, true, "Scrolled body");
// Do a frame reconstruction on the body while also shortening the
// height.
document.body.classList.toggle('noscroll');
document.documentElement.classList.toggle('reconstruct-body');
document.getElementById('spacer').style.height = '1px';
SimpleTest.is(document.body.scrollTop, 0, "Scroll forced to top");
// Do another frame reconstruction while lengthening the height again.
document.body.classList.toggle('noscroll');
document.documentElement.classList.toggle('reconstruct-body');
document.getElementById('spacer').style.height = '5000px';
SimpleTest.is(document.body.scrollTop, 0, "Scroll remained at top");
SimpleTest.finish();
}
</script>
</head>
<body onload="setTimeout(run, 0)">
<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1268195">Mozilla Bug 1268195</a><br/>
The scroll position should end the top of the page. This is the top, yay!
<div id="spacer" style="height: 5000px"></div>
The scroll position should end the top of the page. This is the bottom!
<pre id="test">
</pre>
</body>
</html>