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Test Info: Warnings
- This test has a WPT meta file that expects 4 subtest issues.
- This WPT test may be referenced by the following Test IDs:
- /css/css-anchor-position/anchor-scroll-position-try-011.html - WPT Dashboard Interop Dashboard
<!DOCTYPE html>
<title>Tests position fallback with initially out-of-viewport anchor in columb-reverse flexbox</title>
<link rel="author" href="mailto:xiaochengh@chromium.org">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="support/test-common.js"></script>
<style>
.flex {
display: flex;
flex-direction: column-reverse;
}
#container {
transform: scale(1);
width: fit-content;
height: fit-content;
margin: 100px;
}
#scroller {
width: 400px;
height: 400px;
overflow: scroll;
}
#scroll-content {
min-width: 800px;
min-height: 800px;
}
#anchor {
anchor-name: --a;
width: 100px;
height: 100px;
margin-bottom: 400px;
margin-inline-start: 400px;
background: orange;
}
#anchored {
position: absolute;
width: 100px;
height: 100px;
background: green;
position-anchor: --a;
position-try-fallbacks: --pf1, --pf2, --pf3;
bottom: anchor(top);
left: anchor(right);
}
@position-try --pf1 {
inset: auto;
top: anchor(bottom);
left: anchor(right);
}
@position-try --pf2 {
inset: auto;
bottom: anchor(top);
right: anchor(left);
}
@position-try --pf3 {
inset: auto;
top: anchor(bottom);
right: anchor(left);
}
</style>
<!-- Use flex column-reverse to make everything bottom-up -->
<div id="container" class="flex">
<div id="scroller" class="flex">
<div id="scroll-content" class="flex">
<div id="anchor" class="flex"></div>
</div>
</div>
<div id="anchored" class="flex"></div>
</div>
<script>
promise_test(async () => {
await waitUntilNextAnimationFrame();
assert_fallback_position(anchored, anchor, 'bottom');
assert_fallback_position(anchored, anchor, 'left');
}, 'Should use the last fallback position initially');
promise_test(async () => {
// Scroll up to have enough space above the anchor, but not enough right.
scroller.scrollTop = -250;
scroller.scrollLeft = 150;
await waitUntilNextAnimationFrame();
assert_fallback_position(anchored, anchor, 'top');
assert_fallback_position(anchored, anchor, 'left');
}, 'Should use the third fallback position with enough space above');
promise_test(async () => {
// Scroll right to have enough space right to the anchor, but not enough above.
scroller.scrollTop = -150;
scroller.scrollLeft = 250;
await waitUntilNextAnimationFrame();
assert_fallback_position(anchored, anchor, 'bottom');
assert_fallback_position(anchored, anchor, 'right');
}, 'Should use the second fallback position with enough space right');
promise_test(async () => {
// Scroll up and right to have enough space on both axes.
scroller.scrollTop = -250;
scroller.scrollLeft = 250;
await waitUntilNextAnimationFrame();
assert_fallback_position(anchored, anchor, 'top');
assert_fallback_position(anchored, anchor, 'right');
}, 'Should use the first fallback position with enough space above and right');
</script>