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<!DOCTYPE HTML>
<head>
<title>APZ overscroll handoff for fixed elements</title>
<script type="application/javascript" src="apz_test_utils.js"></script>
<script type="application/javascript" src="apz_test_native_event_utils.js"></script>
<script src="/tests/SimpleTest/paint_listener.js"></script>
<meta name="viewport" content="width=device-width"/>
<style>
html, body {
margin: 0;
}
#scrolled {
overflow: auto;
background: blue;
width: 400px;
height: 400px;
}
.spacer {
height: 2000px;
}
#fixed {
position: fixed;
background: red;
top: 0;
left: 0;
}
#subframe {
overflow: auto;
width: 200px;
height: 200px;
}
</style>
</head>
<div id="scrolled">
<div id="fixed">
<div>
<div id="subframe">
<div id="firstspacer" class="spacer"></div>
</div>
</div>
</div>
<div id="secondspacer" class="spacer"></div>
</div>
<script type="application/javascript">
async function test() {
// Scroll to the bottom of the fixed position element that should not
// allow overscroll handoff.
subframe.scrollTop = subframe.scrollHeight;
// After scrolling to bottom tick the refresh driver.
await promiseFrame();
info("Before scroll: subframe=" + subframe.scrollTop + " scrolled=" +
scrolled.scrollTop);
// Async scroll the fixed element by 200 pixels using the mouse-wheel.
// This should not handoff the overscroll.
await promiseMoveMouseAndScrollWheelOver(subframe, 50, 50, false, 200);
// Make sure scrolling that has happened is propagated to the main thread.
await promiseApzFlushedRepaints();
// Try another gesture to ensure the overscroll handoff runs.
await promiseMoveMouseAndScrollWheelOver(subframe, 50, 50, false, 200);
await promiseApzFlushedRepaints();
info("After scroll: subframe=" + subframe.scrollTop + " scrolled=" +
scrolled.scrollTop);
// Ensure that the scrolled element has not scrolled.
is(scrolled.scrollTop, 0, "scrolled: The overscroll should not handoff");
}
waitUntilApzStable()
.then(test)
.then(subtestDone, subtestFailed);
</script>