| <!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> |