mozilla-central/testing/web-platform/tests/scroll-animations/css/scroll-timeline-nearest-with-absolute-positioned-element.html

Source code

Revision control

Copy as Markdown

Other Tools

Test Info: Warnings

<!DOCTYPE html>
<title>The animation-timeline: scroll-timeline-name</title>
<meta name="viewport" content="width=device-width,initial-scale=1,minimum-scale=1">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/web-animations/testcommon.js"></script>
<script src="support/testcommon.js"></script>
<style>
@keyframes grow-progress {
to { width: 300px; }
}
.scrollcontainer {
overflow-x: scroll;
display: flex;
flex-direction: row;
scroll-timeline: --timeline inline;
}
.progress {
position: absolute;
z-index: 10;
left: 0;
top: 0;
width: 100px;
height: 1em;
background: red;
animation: auto grow-progress linear forwards;
animation-timeline: scroll(inline nearest);
}
.entry {
min-height: 90vh;
min-width: 100vw;
}
.entry:nth-child(even) {
background-color: #eee;
}
.entry:nth-child(odd) {
background-color: #ddd;
}
</style>
<body>
<div class = "scrollcontainer" id = "scroller">
<div class = "progress" id = "target"></div>
<div class = "entry"></div>
<div class = "entry"></div>
<div class = "entry"></div>
</div>
</body>
<script>
"use strict";
setup(assert_implements_animation_timeline);
promise_test(async t => {
const maxScroll = scroller.scrollWidth - scroller.clientWidth;
scroller.scrollLeft = maxScroll;
// Advance to next frame so that scroll-timeline has a valid time.
await waitForNextFrame();
// Flex container is not position relative and therefore not the container for
// the progress element.
assert_equals(getComputedStyle(target).width, "100px");
// Once the scroller is position relative, it becomes the container block for
// the progress element.
scroller.style.position = 'relative';
await waitForNextFrame();
assert_equals(getComputedStyle(target).width, "300px");
}, 'Resolving scroll(nearest) for an absolutely positioned element');
</script>