scrollbar-gutter-propagation-003.html (1736B)
1 <!doctype html> 2 <meta charset="utf-8"> 3 <title>CSS Overflow: scrollbar-gutter on the root with overflow:auto, not scrolling</title> 4 <link rel="author" title="Felipe Erias Morandeira" href="mailto:felipeerias@igalia.com" /> 5 <link rel="help" href="https://drafts.csswg.org/css-overflow-4/#scrollbar-gutter-property" /> 6 <script src="/resources/testharness.js"></script> 7 <script src="/resources/testharnessreport.js"></script> 8 <script src="/css/support/parsing-testcommon.js"></script> 9 <style> 10 body, 11 html { 12 margin: 0; 13 padding: 0; 14 border: none; 15 } 16 17 :root { 18 scrollbar-gutter: stable; 19 overflow: auto; 20 } 21 22 #content { 23 background: green; 24 width: 100%; 25 height: 100px; 26 } 27 </style> 28 29 <body> 30 31 <div id="content"></div> 32 33 <script type="text/javascript"> 34 setup({ explicit_done: true }); 35 36 test(function () { 37 let root = document.documentElement; 38 let body = document.body; 39 let content = document.getElementById('content'); 40 41 // Note: as per the spec, the clientWidth of the root element is 42 // "viewport width excluding the size of a rendered scroll bar (if any)" 43 // which does not take scrollbar-gutter into account. 44 // Since no such special case exists for offsetWidth, this means that here 45 // root.clientWidth is greater than root.offsetWidth (!!!). 46 47 assert_less_than(root.offsetWidth, window.innerWidth, "viewport has gutter"); 48 assert_equals(body.offsetWidth, root.offsetWidth, "body matches root"); 49 assert_equals(body.clientWidth, body.offsetWidth, "body has no gutter"); 50 assert_equals(content.offsetWidth, body.clientWidth, "content matches body"); 51 }, "viewport has gutter, others do not"); 52 53 done(); 54 55 </script> 56 </body>