view-timeline-sticky-offscreen-2.html

<!DOCTYPE html>
<html id="top">
<head>
<meta charset="utf-8">
<title>View timeline with sticky during entry/exit</title>
<link rel="help" href="https://drafts.csswg.org/scroll-animations-1/#viewtimeline-interface">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/web-animations/testcommon.js"></script>
<script src="/scroll-animations/scroll-timelines/testcommon.js"></script>
<script src="/scroll-animations/view-timelines/testcommon.js"></script>
<style>

#container {
  height: 500px;
  overflow: auto;
}
.space {
  height: 550px;
}

/* bottom-sticky during entry and top-sticky during exit */
.stickycase2 {
  background: yellow;
  position: sticky;
  top: -100px;
  bottom: -100px;
  height: 200px;
}

#target {
  position: relative;
  top: 50px;
  background: orange;
  height: 100px;
}

</style>
</head>
<body>
<div id="container">
  <div class="space"></div>
  <div class="space">
    <div style="height: 150px"></div>
    <div id="sticky" class="stickycase2">
      <div id="target">Subject</div>
    </div>
  </div>
  <div class="space"></div>
</div>
<script type="text/javascript">

// The "cover" range would be [STATIC_START, STATIC_END] if we ignored
// stickiness (i.e., considered only static position).
//
// STATIC_START = scroll distance to second spacer (50px)
//              + position of sticky element within its container (150px)
//              + position of target within sticky element (50px)
// STATIC_END = STATIC_START
//            + viewport height (500px)
//            + target height (100px)
const STATIC_START = 250;
const STATIC_END = 850;

// This is how far the sticky element can move upwards when bottom-stuck.
const ROOM_ABOVE = 150;

// This is how far the sticky element can move downwards when top-stuck.
const ROOM_BELOW = 200;

const TARGET_HEIGHT = 100;
const VIEWPORT_HEIGHT = 500;

promise_test(async t => {
  await runTimelineRangeTest(t, {
    rangeStart: { rangeName: 'cover', offset: CSS.percent(0) } ,
    rangeEnd: { rangeName: 'cover', offset: CSS.percent(100) },
    startOffset: STATIC_START - ROOM_ABOVE,
    endOffset: STATIC_END + ROOM_BELOW,
    axis: 'block'
  });
  await runTimelineRangeTest(t, {
    rangeStart: { rangeName: 'contain', offset: CSS.percent(0) } ,
    rangeEnd: { rangeName: 'contain', offset: CSS.percent(100) },
    startOffset: STATIC_START + TARGET_HEIGHT,
    endOffset: STATIC_END - TARGET_HEIGHT,
    axis: 'block'
  });
  await runTimelineRangeTest(t, {
    rangeStart: { rangeName: 'entry', offset: CSS.percent(0) },
    rangeEnd: { rangeName: 'entry', offset: CSS.percent(100) },
    startOffset: STATIC_START - ROOM_ABOVE,
    endOffset: STATIC_START + TARGET_HEIGHT,
    axis: 'block'
  });
  await runTimelineRangeTest(t, {
    rangeStart: { rangeName: 'entry-crossing', offset: CSS.percent(0) },
    rangeEnd: { rangeName: 'entry-crossing', offset: CSS.percent(100) },
    startOffset: STATIC_START - ROOM_ABOVE,
    endOffset: STATIC_START + TARGET_HEIGHT,
    axis: 'block'
  });
  await runTimelineRangeTest(t, {
    rangeStart:  { rangeName: 'exit', offset: CSS.percent(0) },
    rangeEnd: { rangeName: 'exit', offset: CSS.percent(100) },
    startOffset: STATIC_END - TARGET_HEIGHT,
    endOffset: STATIC_END + ROOM_BELOW,
    axis: 'block'
  });
  await runTimelineRangeTest(t, {
    rangeStart:  { rangeName: 'exit-crossing', offset: CSS.percent(0) },
    rangeEnd: { rangeName: 'exit-crossing', offset: CSS.percent(100) },
    startOffset: STATIC_END - TARGET_HEIGHT,
    endOffset: STATIC_END + ROOM_BELOW,
    axis: 'block'
  });
}, 'View timeline bottom-sticky during entry and top-sticky during exit.');

</script>
</body>
</html>
chromium/third_party/blink/web_tests/external/wpt/scroll-animations/view-timelines/sticky/view-timeline-sticky-offscreen-2.html
