| <!DOCTYPE html> |
| <script src="../../resources/testharness.js"></script> |
| <script src="../../resources/testharnessreport.js"></script> |
| <style> |
| div::-webkit-scrollbar { |
| display: none; |
| } |
| </style> |
| <div id=scroller style="width: 400px; height: 400px; overflow-y: scroll; will-change: transform"> |
| <div style="height: 400px"></div> |
| <div id=overlap style="backface-visibility: hidden; width: 100px; height: 100px; background-color: red"></div> |
| <div id=target style="position: relative; top: -50px; left: 50px; width: 100px; height: 100px; background-color: green"></div> |
| </div> |
| <div id="notscrolled" style="position: relative; width: 50px; height: 300px; background: lightgray"></div> |
| <script> |
| // Test passes if 'target' (green) is on top of 'overlap' (red). |
| // The actual test output is a layerization where 'overlap' has a composited layer, |
| // and 'target' does, but not 'notscrolled'. 'target' has a composited layer because |
| // it overlaps 'overlap'. 'notscrolled' does not have one because it does not |
| // intersect the scroller and is outside of it. |
| |
| function drawsContentAndLayoutObject(layer) { |
| if (layer.drawsContent === false) |
| return false; |
| if (!layer.name.includes("Layout")) |
| return false; |
| return true; |
| } |
| |
| var t = async_test(); |
| |
| onload = function() { |
| requestAnimationFrame(function() { |
| requestAnimationFrame(function() { |
| scroller.scrollTop = 400; |
| if (internals) { |
| t.step(function() { |
| var layers_dump = internals.layerTreeAsText(document); |
| var layers = JSON.parse(layers_dump).layers; |
| var desiredLayers = layers.filter(drawsContentAndLayoutObject); |
| assert_equals(desiredLayers.length, 3, "Actual layers: " + layers_dump); |
| assert_true(desiredLayers[0].name.includes("scroller"), "scroller"); |
| assert_true(desiredLayers[1].name.includes("overlap"), "overlap"); |
| assert_true(desiredLayers[2].name.includes("target"), "target"); |
| }); |
| } |
| t.done(); |
| }); |
| }); |
| }; |
| </script> |