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<!DOCTYPE HTML>
<html>
<head>
  <title>APZ overscroll handoff for sticky 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 {
  height: 100%;
  overflow: hidden;
  margin: 0;
}
#main {
  height: 100%;
  overflow: auto;
}
#spacer  {
  height: 5000px;
}
#sticky {
  position: sticky;
  top: 50%;
  left: 0;
  width: 100%;
  height: 100px;
  background: red;
  overflow: auto;
}
#long {
  height: 250px;
  width: 50%;
  position: absolute;
  background: green;
  top: 0;
  left: 25%;
}
  </style>
</head>
<body>
  <div id="main">
    <div id="sticky">
      <div id="long">
      </div>
    </div>
    <div id="spacer">
    </div>
  </div>
</body>
<script type="application/javascript">
async function test() {
  // Scroll to the bottom of the sticky position element that should not
  // allow overscroll handoff.
  sticky.scrollTop = sticky.scrollHeight;
  // After scrolling to bottom tick the refresh driver.
  await promiseFrame();
  info("Start: sticky=" + sticky.scrollTop + " main=" + main.scrollTop);
  let transformEnd = promiseTransformEnd();
  // Async scroll the sticky element by 200 pixels using the mouse-wheel.
  // This should handoff the overscroll to the parent element.
  await promiseMoveMouseAndScrollWheelOver(sticky, 25, 25, false, 200);
  // Wait for the trasform triggered by the gesture to complete.
  await transformEnd;
  await promiseApzFlushedRepaints();
  info("After scroll: sticky=" + sticky.scrollTop + " main=" + main.scrollTop);
  // Ensure that the main element has scrolled.
  isnot(main.scrollTop, 0, "The overscroll should handoff");
}
waitUntilApzStable()
.then(test)
.then(subtestDone, subtestFailed);
</script>
</html>