1 files changed, 49 insertions, 0 deletions
diff --git a/testing/web-platform/tests/css/css-scroll-snap/scroll-padding.html b/testing/web-platform/tests/css/css-scroll-snap/scroll-padding.html
new file mode 100644
index 0000000000..0c637ed6db
--- /dev/null
+++ b/testing/web-platform/tests/css/css-scroll-snap/scroll-padding.html
@@ -0,0 +1,49 @@
+<!DOCTYPE html>
+<link rel="help" href="https://drafts.csswg.org/css-scroll-snap-1/#scroll-padding" />
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<style>
+div {
+  position: absolute;
+  margin: 0px;
+}
+#scroller {
+  height: 500px;
+  width: 500px;
+  overflow: hidden;
+  scroll-snap-type: both mandatory;
+}
+#target {
+  width: 300px;
+  height: 300px;
+  background-color: blue;
+}
+</style>
+
+<div id="scroller">
+  <div style="width: 2000px; height: 2000px;"></div>
+  <div id="target"></div>
+</div>
+
+<script>
+test(() => {
+  scroller.style.scrollPadding = "100px";
+
+  target.style.scrollSnapAlign = "start";
+  target.style.left = "300px";
+  target.style.top = "300px";
+
+  scroller.scrollTo(0, 0);
+  // `target position (300px, 300px)` - `padding (100px, 100px)`.
+  assert_equals(scroller.scrollLeft, 200);
+  assert_equals(scroller.scrollTop, 200);
+
+  target.style.scrollSnapAlign = "end";
+
+  // `target position (300px, 300px)` + `target size (300px, 300px) +
+  // `padding (100px, 100px) - `scroller size (500px, 500px)`.
+  scroller.scrollTo(0, 0);
+  assert_equals(scroller.scrollLeft, 200);
+  assert_equals(scroller.scrollTop, 200);
+}, "Snaps to the positions adjusted by scroll-padding");
+</script>