summaryrefslogtreecommitdiffstats
path: root/testing/web-platform/tests/css/css-scroll-anchoring/opt-out-dynamic.html
diff options
context:
space:
mode:
Diffstat (limited to 'testing/web-platform/tests/css/css-scroll-anchoring/opt-out-dynamic.html')
-rw-r--r--testing/web-platform/tests/css/css-scroll-anchoring/opt-out-dynamic.html51
1 files changed, 51 insertions, 0 deletions
diff --git a/testing/web-platform/tests/css/css-scroll-anchoring/opt-out-dynamic.html b/testing/web-platform/tests/css/css-scroll-anchoring/opt-out-dynamic.html
new file mode 100644
index 0000000000..ec548dc3d6
--- /dev/null
+++ b/testing/web-platform/tests/css/css-scroll-anchoring/opt-out-dynamic.html
@@ -0,0 +1,51 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<link rel="help" href="https://drafts.csswg.org/css-scroll-anchoring-1/">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<style>
+
+#scroller {
+ overflow: scroll;
+ width: 300px;
+ height: 300px;
+}
+#before { height: 50px; }
+#content { margin-top: 100px; margin-bottom: 600px; }
+.no { overflow-anchor: none; }
+
+</style>
+<div id="scroller">
+ <div id="before"></div>
+ <div id="content">content</div>
+</div>
+<script>
+
+// Tests that dynamic styling 'overflow-anchor' on an anchor node has the
+// same effect as initial styling
+
+test(() => {
+ let scroller = document.querySelector("#scroller");
+ let before = document.querySelector("#before");
+ let content = document.querySelector("#content");
+
+ // Scroll down so that #content is the first element in the viewport
+ scroller.scrollTop = 100;
+
+ // Change the height of #before to trigger a scroll adjustment. This ensures
+ // that #content was selected as a scroll anchor
+ before.style.height = "100px";
+ assert_equals(scroller.scrollTop, 150);
+
+ // Now set 'overflow-anchor: none' on #content. This should invalidate the
+ // scroll anchor, and #scroller should recalculate its anchor. There are no
+ // other valid anchors in the viewport, so there should be no anchor.
+ content.className = 'no';
+
+ // Change the height of #before and make sure we don't adjust. This ensures
+ // that #content was not selected as a scroll anchor
+ before.style.height = "150px";
+ assert_equals(scroller.scrollTop, 150);
+}, "Dynamically styling 'overflow-anchor: none' on the anchor node should prevent scroll anchoring");
+
+</script>