<!DOCTYPE html>
<title>cssom-view - scroll-behavior: smooth</title>
<meta name="timeout" content="long">
<link rel="author" title="Rune Lillesveen" href="mailto:[email protected]">
<link rel="help" href="https://drafts.csswg.org/cssom-view/#smooth-scrolling">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/dom/events/scrolling/scroll_support.js"></script>
<style>
.filler { height: 10000px }
.smooth {
scroll-behavior: smooth;
}
#scrollable {
overflow: scroll;
width: 100px;
height: 100px;
}
</style>
<div id="testContainer">
<div id="scrollable">
<div class="filler"></div>
</div>
<div class="filler"></div>
</div>
<script>
promise_test(async () => {
await waitForCompositorReady();
}, "Make sure the page is ready for animation.");
test(() => {
scrollable.scrollTo(0, 5000);
assert_equals(scrollable.scrollTop, 5000, "Initially scrolls instantly");
scrollable.scrollTo(0, 0);
scrollable.className = "smooth";
scrollable.scrollTo(0, 5000);
assert_less_than(scrollable.scrollTop, 5000, "scroll-behavior:smooth should not scroll instantly");
scrollable.className = "";
scrollable.scrollTo(0, 0);
}, "scroll-behavior: smooth on DIV element");
test(() => {
window.scrollTo(0, 5000);
assert_equals(window.scrollY, 5000, "Initially scrolls instantly");
window.scrollTo(0, 0);
document.documentElement.className = "smooth";
assert_less_than(window.scrollY, 5000, "scroll-behavior:smooth should not scroll instantly");
document.documentElement.className = "";
window.scrollTo(0, 0);
}, "HTML element scroll-behavior should propagate to viewport");
test(() => {
window.scrollTo(0, 5000);
assert_equals(window.scrollY, 5000, "Initially scrolls instantly");
window.scrollTo(0, 0);
document.body.className = "smooth";
window.scrollTo(0, 5000);
assert_equals(window.scrollY, 5000, "scroll-behavior:smooth on BODY should scroll viewport instantly");
document.body.className = "";
window.scrollTo(0, 0);
}, "BODY element scroll-behavior should not propagate to viewport");
testContainer.style.display = "none";
</script>
Codebase Browser
chromium