74 lines
3.2 KiB
HTML
74 lines
3.2 KiB
HTML
<!DOCTYPE html>
|
|
<title>Nested top-constrainted position:sticky elements should render correctly</title>
|
|
<link rel="help" href="https://www.w3.org/TR/css-position-3/#sticky-pos" />
|
|
<meta name="assert" content="This test checks that nested position:sticky elements with a top constraint render correctly" />
|
|
|
|
<script src="/resources/testharness.js"></script>
|
|
<script src="/resources/testharnessreport.js"></script>
|
|
|
|
<script src="../resources/sticky-util.js"></script>
|
|
|
|
<body></body>
|
|
|
|
<script>
|
|
test(() => {
|
|
const elements = setupNestedStickyTest('top', 50, 60);
|
|
elements.scroller.scrollTop = 100;
|
|
const nonStickyTopY = elements.container.offsetTop +
|
|
elements.filler.clientHeight;
|
|
assert_equals(elements.sticky.offsetTop, nonStickyTopY);
|
|
// The inner sticky should not be offset from the outer.
|
|
assert_equals(elements.innerSticky.offsetTop, 0);
|
|
}, 'before reaching the sticking point, neither sticky box should be offset');
|
|
|
|
test(() => {
|
|
const elements = setupNestedStickyTest('top', 50, 60);
|
|
elements.scroller.scrollTop = 145;
|
|
const nonStickyTopY = elements.container.offsetTop +
|
|
elements.filler.clientHeight;
|
|
assert_equals(elements.sticky.offsetTop, nonStickyTopY);
|
|
assert_equals(elements.innerSticky.offsetTop, 5);
|
|
}, 'the inner sticky can stick before the outer one if necessary');
|
|
|
|
test(() => {
|
|
const elements = setupNestedStickyTest('top', 50, 60);
|
|
elements.scroller.scrollTop = 200;
|
|
|
|
// This math cancels to sticky.offsetTop == (scroller.scrollTop + 50), but
|
|
// for clarity the calculations are left explicit.
|
|
const nonStickyTopY = elements.container.offsetTop +
|
|
elements.filler.clientHeight;
|
|
const targetTopY = elements.scroller.scrollTop + 50;
|
|
const stickyOffset = targetTopY - nonStickyTopY;
|
|
assert_equals(elements.sticky.offsetTop, nonStickyTopY + stickyOffset);
|
|
|
|
// The inner sticky has similar math, but its offsetTop is relative to the
|
|
// sticky element and in this test is the difference between the top values.
|
|
assert_equals(elements.innerSticky.offsetTop, 10);
|
|
}, 'both sticky boxes can be stuck at the same time');
|
|
|
|
test(() => {
|
|
const elements = setupNestedStickyTest('top', 50, 60);
|
|
elements.scroller.scrollTop = 300;
|
|
const maxOffsetInContainer = elements.container.offsetTop +
|
|
elements.container.clientHeight - elements.sticky.clientHeight;
|
|
assert_equals(elements.sticky.offsetTop, maxOffsetInContainer);
|
|
const maxOffsetInOuterSticky = elements.sticky.clientHeight -
|
|
elements.innerSticky.clientHeight;
|
|
assert_equals(elements.innerSticky.offsetTop, maxOffsetInOuterSticky);
|
|
}, 'neither sticky can escape their containing block');
|
|
|
|
test(() => {
|
|
const elements = setupNestedStickyTest('top', 50, 300);
|
|
elements.scroller.scrollTop = 100;
|
|
// The outer sticky has not stuck yet.
|
|
const nonStickyTopY = elements.container.offsetTop +
|
|
elements.filler.clientHeight;
|
|
assert_equals(elements.sticky.offsetTop, nonStickyTopY);
|
|
// But the inner sticky still cannot escape the outer sticky (as it is the
|
|
// containing block).
|
|
const maxOffsetInOuterSticky = elements.sticky.clientHeight -
|
|
elements.innerSticky.clientHeight;
|
|
assert_equals(elements.innerSticky.offsetTop, maxOffsetInOuterSticky);
|
|
}, 'the inner sticky cannot be pushed outside the outer sticky');
|
|
</script>
|