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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title> CSS Scroll Snap 2 Test: scroll-start-target*</title>
<link rel="help" href="https://drafts.csswg.org/css-scroll-snap-2/#scroll-start-target">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/resources/testdriver.js"></script>
<script src="/resources/testdriver-actions.js"></script>
<script src="/resources/testdriver-vendor.js"></script>
<script src="/dom/events/scrolling/scroll_support.js"></script>
</head>
<body>
<style>
#space-filler {
width: 500px;
height: 500px;
background-color: green;
}
#outer-container {
width: 400px;
height: 400px;
overflow: scroll;
background-color: yellow;
}
#inner-container {
top: 20px;
left: 20px;
width: 300px;
height: 300px;
overflow: visible;
position: relative;
background-color: blue;
}
#target {
width: 100px;
height: 100px;
background-color: pink;
scroll-start-target: auto auto;
}
</style>
<div id="outer-container">
<div id="space-filler"></div>
<div id="inner-container">
<div id="space-filler"></div>
<div id="target">
</div>
</div>
</div>
<script>
let outer_container = document.getElementById("outer-container");
let inner_container = document.getElementById("inner-container");
let space_filler = document.getElementById("space-filler");
let target = document.getElementById("target");
const inner_scroller_top_offset = 20;
const target_height = target.getBoundingClientRect().height;
const space_filler_height = space_filler.getBoundingClientRect().height;
const inner_content_height = target_height + space_filler_height;
const inner_container_height = inner_container.getBoundingClientRect().height;
async function resetDisplay() {
return new Promise((resolve) => {
if (getComputedStyle(outer_container).display == "block" &&
getComputedStyle(inner_container).display == "block" &&
getComputedStyle(target).display == "block") {
resolve();
} else {
outer_container.style.display = "block";
inner_container.style.display = "block";
target.style.display = "block";
requestAnimationFrame(async () => {
await resetDisplay();
resolve();
});
}
});
}
async function waitForCSSProperty(element, property, value) {
return new Promise((resolve) => {
if (getComputedStyle(element)[property] == value) {
resolve();
} else {
requestAnimationFrame(async () => {
await waitForCSSProperty(element, property, value);
resolve();
})
}
});
}
async function waitForDisplay(element, value) {
return waitForCSSProperty(element, "display", value);
}
async function waitForOverflow(element, value) {
return waitForCSSProperty(element, "overflow", value);
}
let initial_expected_scroll_top = space_filler_height +
inner_scroller_top_offset + inner_content_height -
outer_container.clientHeight;
promise_test(async (t) => {
await resetDisplay();
assert_equals(outer_container.scrollTop, initial_expected_scroll_top,
"outer-container is scrolled to scroll-start-target");
inner_container.style.display = "none";
await waitForDisplay(inner_container, "none");
assert_equals(outer_container.scrollTop,
space_filler_height - outer_container.clientHeight,
"outer-container has no content to scroll");
inner_container.style.display = "block";
await waitForDisplay(inner_container, "block");
assert_equals(outer_container.scrollTop, initial_expected_scroll_top,
"outer-scroller is updated as scroll-start-target reappears");
}, "display:none scroll-start-target becomes display:block");
promise_test(async (t) => {
await waitForCompositorCommit();
await resetDisplay();
assert_equals(outer_container.scrollTop, initial_expected_scroll_top,
"outer-container is scrolled to scroll-start-target");
inner_container.style.overflow = "scroll";
await waitForOverflow(inner_container, "scroll");
// inner-container has become a scroller and should be scrolled to
// scroll-start-target.
assert_equals(inner_container.scrollTop,
inner_content_height - inner_container.clientHeight,
"inner-container is fully scrolled to target");
// outer-container should be adjusted to its new max scroll offset.
const scrollbar_width = outer_container.offsetHeight -
outer_container.clientHeight;
assert_equals(outer_container.scrollTop,
space_filler_height + inner_scroller_top_offset +
inner_container_height - outer_container.clientHeight,
"outer-container's overflowing content is only its direct " +
"children");
inner_container.style.overflow = "visible";
await waitForOverflow(inner_container, "visible");
assert_equals(inner_container.scrollTop, 0,
"inner-container is no longer a scroll container");
assert_equals(outer_container.scrollTop, initial_expected_scroll_top,
"outer-scroller is the scroll container for target once again");
}, "intermediate overflow:visible container becomes overflow:scroll");
promise_test(async (t) => {
// This test verifies that:
// 1. when both the child and grandchild are scroll-start-targets, the
// grandchild wins/is scrolled to.
// 2. if/when the grandchild stops being a scroll-start-target, the
// child (inner container) is scrolled to.
await waitForCompositorCommit();
await resetDisplay();
t.add_cleanup(async () => {
target.style.scrollStartTarget = "auto auto";
await waitForCSSProperty(target, "scroll-start-target", "auto");
});
assert_equals(outer_container.scrollTop, initial_expected_scroll_top,
"outer-container is scrolled to scroll-start-target");
// Make the inner container a scroll-start-target.
inner_container.style.scrollStartTarget = "auto auto";
await waitForCSSProperty(inner_container, "scroll-start-target", "auto");
// The inner container has overflow: visible, so it's not the scroll
// container of target.
assert_equals(outer_container.scrollTop, initial_expected_scroll_top,
"outer-container is still scrolled to inner scroll-start-target");
// Make target no longer a scroll-start-target. The outer container's
// scroll-start-target should now be the inner container.
target.style.scrollStartTarget = "none none";
await waitForCSSProperty(target, "scroll-start-target", "none");
assert_equals(outer_container.scrollTop,
space_filler_height + inner_scroller_top_offset,
"outer-container is scrolled to inner-container");
}, "inner scroll-start-target takes precedence over outer");
promise_test(async (t) => {
// This test verifies that a child which is a scroller, is a
// scroll-start-target, and has a scroll-start-target is scrolled to by
// its scrolling container, and also scrolls to its own
// scroll-start-target.
await waitForCompositorCommit();
await resetDisplay();
t.add_cleanup(async () => {
inner_container.style.overflow = "visible";
inner_container.style.scrollStartTarget = "none none";
await waitForCSSProperty(inner_container, "overflow",
"visible");
await waitForCSSProperty(inner_container, "scroll-start-target",
"none");
});
assert_equals(outer_container.scrollTop, initial_expected_scroll_top,
"outer-container is scrolled to scroll-start-target");
// Make the inner container a scroll-start-target.
inner_container.style.scrollStartTarget = "auto auto";
await waitForCSSProperty(inner_container, "scroll-start-target", "auto");
assert_equals(outer_container.scrollTop, initial_expected_scroll_top,
"outer-container is still scrolled to inner scroll-start-target");
// Make the inner container a scroller.
inner_container.style.overflow = "scroll";
await waitForOverflow(inner_container, "scroll");
assert_equals(outer_container.scrollTop,
space_filler_height + inner_scroller_top_offset +
inner_container.offsetHeight - outer_container.clientHeight,
"outer-container is scrolled to the inner container");
assert_equals(inner_container.scrollTop,
space_filler_height + target.offsetHeight -
inner_container.clientHeight,
"inner-container is scrolled to target");
}, "scroll containers can also be scroll-start-targets");
</script>
</body>
</html>
|
