<!DOCTYPE HTML>
<html>
<head>
<title>Test that we don't get unnecessary repaints with fixed backgrounds</title>
<script type="application/javascript" src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
<script type="text/javascript" src="chrome://mochikit/content/tests/SimpleTest/paint_listener.js"></script>
<link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"/>
</head>
<!-- Need a timeout here to allow paint unsuppression before we start the test -->
<body onload="setTimeout(startTest,0)" style="background:url(blue-32x32.png) top left no-repeat fixed; background-size: 100px 2000px; overflow:hidden;">
<div style="height: 2048px"></div>
<pre id="test">
<script type="application/javascript">
SimpleTest.waitForExplicitFinish();
var utils = window.QueryInterface(Components.interfaces.nsIInterfaceRequestor).
getInterface(Components.interfaces.nsIDOMWindowUtils);
function startTest() {
// Do a scroll to ensure we trigger activity heuristics.
document.documentElement.scrollTop = 1;
waitForAllPaintsFlushed(function () {
document.documentElement.scrollTop = 0;
waitForAllPaintsFlushed(function () {
// Clear paint state and scroll down
utils.checkAndClearPaintedState(document.documentElement);
document.documentElement.scrollTop = 100;
waitForAllPaintsFlushed(function () {
// Make sure nothing painted
var painted = utils.checkAndClearPaintedState(document.documentElement);
is(painted, false, "Fixed background should not have been painted when scrolled");
SimpleTest.finish();
});
});
});
}
</script>
</pre>
</body>
</html>