| <!DOCTYPE html> |
| <title>Sticky positioning can cause overflow but must be accessible.</title> |
| <link rel="help" href="https://www.w3.org/TR/css-position-3/#sticky-pos" /> |
| <meta name="assert" content="This test checks that a sticky positioned element |
| can cause overflow but must still be accessible through scrolling" /> |
| |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| |
| <style> |
| .container { |
| overflow: scroll; |
| width: 100px; |
| height: 100px; |
| } |
| |
| .box { |
| background-color: green; |
| height: 50px; |
| width: 50px; |
| } |
| |
| .sticky { |
| position: sticky; |
| top: 200px; /* Forces the sticky position element below the overflow. */ |
| } |
| </style> |
| |
| <div id="scroller1" class="container"> |
| <div class="sticky box"></div> |
| </div> |
| |
| <div id="scroller2" class="container"> |
| <div class="sticky box"></div> |
| </div> |
| |
| <script> |
| test(() => { |
| var scroller = document.getElementById('scroller1'); |
| var sticky = scroller.querySelector('.sticky'); |
| |
| var stickyOffset = sticky.offsetTop - |
| scroller.scrollTop - scroller.offsetTop; |
| assert_equals(stickyOffset, 200); |
| assert_equals(scroller.scrollHeight, 250); |
| }, 'sticky position offset should be able to cause overflow'); |
| |
| test(() => { |
| var scroller = document.getElementById('scroller2'); |
| var sticky = scroller.querySelector('.sticky'); |
| |
| scroller.scrollTop = 150; |
| var stickyOffset = sticky.offsetTop - |
| scroller.scrollTop - scroller.offsetTop; |
| assert_equals(stickyOffset, 50); |
| // Scroll height should be unaffected. |
| assert_equals(scroller.scrollHeight, 250); |
| |
| }, 'sticky position offset in overflow should be accessible'); |
| </script> |
