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Test Info: Warnings
- This test has a WPT meta file that expects 1 subtest issues.
- This WPT test may be referenced by the following Test IDs:
- /css/css-contain/content-visibility/content-visibility-anchor-positioning-001.html - WPT Dashboard Interop Dashboard
<!doctype HTML>
<meta charset=utf8>
<title>CSS Content Visibility: auto prevents existing anchors to unskipped content
from becoming skipped</title>
<link rel="author" title="Chris Harrelson" href="mailto:chrishtr@chromium.org">
<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: auto;
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 off-screen and skipped.');
window.scrollTo(0, 0);
await waitForAnimationFrames(2);
assert_equals(positioned.getBoundingClientRect().left, 209,
'#positioned should be anchored because #anchor is on-screen.');
window.scrollTo(0, 10000);
await waitForAnimationFrames(2);
assert_equals(positioned.getBoundingClientRect().left, 209,
'#positioned should be anchored because it was anchored to #anchor before #anchor was scrolled offscreen, so #anchor does not become 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 because it was anchored to #anchor before #anchor was scrolled offscreen, so #anchor does not become skipped.');
lock.style.contentVisibility = "auto";
await waitForAnimationFrames(1);
assert_equals(positioned.getBoundingClientRect().left, 209,
'#positioned should be anchored because it was anchored to #anchor before #anchor was scrolled offscreen, so #anchor does not become skipped.');
positioned.style.right = 'anchor(--anchor2 left)';
assert_equals(positioned.getBoundingClientRect().left, 209,
'#positioned should be anchored because it was anchored to #anchor before #anchor was scrolled offscreen, so #anchor does not become skipped.');
positioned.style.left = 'auto';
assert_equals(positioned.getBoundingClientRect().right, 208,
'#positioned should be anchored because it still has one more anchor.');
});
</script>