<!DOCTYPE html>
<html>
<head>
<link rel="help" href="https://drafts.csswg.org/css-scroll-snap" />
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/dom/events/scrolling/scroll_support.js"></script>
<script src="/resources/testdriver.js"></script>
<script src="/resources/testdriver-actions.js"></script>
<script src="/resources/testdriver-vendor.js"></script>
<script src="resources/common.js" ></script>
</head>
<body>
<style>
.scroller {
overflow: scroll;
position: relative;
height: 400px;
width: 400px;
border:solid 1px black;
scroll-snap-type: y mandatory;
}
.no-snap { scroll-snap-align: none }
.scroller div:focus {
border: solid 1px red;
}
.large-space {
height: 300vh;
width: 300vw;
position: absolute;
}
.target {
scroll-snap-align: start;
position: absolute;
width: 100px;
height: 100px;
border: solid 1px black;
}
.top {
top: 0px;
}
.left {
left: 0px;
}
.right {
left: 200px;
}
.bottom {
top: 200px;
}
.inner {
text-align: right;
}
.inner1 {
height: 150px;
width: 150px;
top: 150px;
left: 100px;
background-color: blue;
}
.inner2 {
height: 100px;
width: 100px;
top: 150px;
left: 100px;
background-color: pink;
}
.inner3 {
height: 75px;
width: 75px;
top: 150px;
left: 100px;
background-color: green;
}
.inner4 {
height: 50px;
width: 50px;
top: 150px;
left: 100px;
background-color: grey;
}
.outer {
height: 200px;
width: 200px;
top: 150px;
left: 50px;
left: 50px;
background-color: yellow;
}
</style>
<div id="scroller" class="scroller">
<div class="large-space"></div>
<div class="top left target">Top Left</div>
<div class="top right target">Top Right</div>
<div class="outer target" id="outer">Outer</div>
<div class="inner inner1 target" id="inner1">I1</div>
<div class="inner inner2 target" id="inner2">I2</div>
<div class="inner inner3 target" id="inner3">I3</div>
<div class="inner inner4 target" id="inner4">I4</div>
</div>
<script>
function cleanup() {
inner.style.top = 100;
outer.style.top = 100;
}
window.onload = (async () => {
const inner1 = document.getElementById("inner1");
const inner2 = document.getElementById("inner2");
const inner3 = document.getElementById("inner3");
const inner4 = document.getElementById("inner4");
const outer = document.getElementById("outer");
const scroller = document.getElementById("scroller");
promise_test(async (t) => {
await waitForCompositorCommit();
await runScrollSnapSelectionVerificationTest(t, scroller,
/*aligned_elements_x=*/[],
/*aligned_elements_y=*/[inner1, inner2, inner3, inner4, outer],
/*axis=*/"y",
/*expected_target_x*/null,
/*expected_target_y*/inner4);
// Push inner4 outside the snapport. It should no longer be considered
// the snap target; inner3 is next in line.
inner4.style.left = "500px";
await runScrollSnapSelectionVerificationTest(t, scroller,
/*aligned_elements_x=*/[],
/*aligned_elements_y=*/[inner1, inner2, inner3, inner4, outer],
/*axis=*/"y",
/*expected_target_x*/null,
/*expected_target_y*/inner3);
// Reset inner4's style.
inner4.style.left = "100px";
}, "snap container selects innermost area as snap target");
promise_test(async (t) => {
t.add_cleanup(() => {
outer.style.top = "150px";
});
await waitForCompositorCommit();
// Move outer target below inner targets.
outer.style.top = "400px";
// Snap to now-below outer target.
scroller.scrollTop = outer.offsetTop;
runLayoutSnapSeletionVerificationTest(t, scroller,
[inner1, inner2, inner3, inner4], outer, "y");
}, "snap container follows selected snap target after layout change " +
"(the pre-existing snap target should not be overriden because of " +
"the innermost area)");
});
</script>
</body>
</html>