content-visibility-anchor-positioning-002.html

<!doctype HTML>
<meta charset=utf8>
<title>CSS Content Visibility: hidden never anchors</title>
<link rel="author" title="Chris Harrelson" href="mailto:[email protected]">
<link rel="help" href="https://drafts.csswg.org/css-anchor-position-1/#anchor-relevance">
<script src="/web-animations/testcommon.js"></script>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>

<style>
#anchor, #positioned {
  width: 200px;
  height: 200px;
}

#lock {
  height: 400px;
  width: 400px;
  content-visibility: hidden;
  border: 1px solid black;
}

pre {
  position: relative;
  top: 200px;
}

#container {
  position:relative;
  height: 10000px;
}

#anchor {
  anchor-name: --anchor;
  background-color: lightblue;
}

#positioned {
  position: absolute;
  background-color: lightgreen;
  left: anchor(right);
}
</style>
<div id=container>
  <div id=lock>
    <div id=anchor></div>
    <div id=anchor2></div>
  </div>
  <div id=positioned></div>
</div>

<pre id=output>
</pre>
<script>
"use strict";

promise_test(async t => {
  window.scrollTo(0, 10000);
  await waitForAnimationFrames(1);

  // When the anchor applies, the positioned element is moved right by 200px.
  positioned.style.positionAnchor = "--anchor";
  assert_equals(positioned.getBoundingClientRect().left, 8,
    '#positioned should not be anchored because #anchor is hidden (always skipped).');

  window.scrollTo(0, 0);
  await waitForAnimationFrames(2);

  assert_equals(positioned.getBoundingClientRect().left, 8,
    '#positioned should not be anchored because #anchor is hidden (always skipped).');

  window.scrollTo(0, 10000);
  await waitForAnimationFrames(2);

  assert_equals(positioned.getBoundingClientRect().left, 8,
    '#positioned should not be anchored because #anchor is hidden (always skipped).');

  lock.style.contentVisibility = "visible";

  assert_equals(positioned.getBoundingClientRect().left, 209,
    "#positioned should be anchored because it's not under a content-visibility ancestor");

  window.scrollTo(0, 0);
  await waitForAnimationFrames(2);
  assert_equals(positioned.getBoundingClientRect().left, 209,
    '#positioned should be anchored regardless of scroll offset.');

  window.scrollTo(0, 10000);
  await waitForAnimationFrames(2);

  assert_equals(positioned.getBoundingClientRect().left, 209,
    '#positioned should be anchored regardless of scroll offset.');

  lock.style.contentVisibility = "hidden";
  await waitForAnimationFrames(1);

  assert_equals(positioned.getBoundingClientRect().left, 8,
    '#positioned should not be anchored because #anchor is hidden (always skipped).');

  positioned.style.right = 'anchor(--anchor2 left)';
  assert_equals(positioned.getBoundingClientRect().left, 8,
    '#positioned should not be anchored because #anchor is hidden (always skipped).');

  positioned.style.left = 'auto';
  assert_equals(positioned.getBoundingClientRect().right, 208,
    '#positioned should not be anchored because #anchor is hidden (always skipped).');

});

</script>
chromium/third_party/blink/web_tests/external/wpt/css/css-contain/content-visibility/content-visibility-anchor-positioning-002.html
