scrollbar-gutter-propagation-001.html (1706B)
1 <!doctype html> 2 <meta charset="utf-8"> 3 <title>CSS Overflow: scrollbar-gutter on the root, 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 } 20 21 #content { 22 background: green; 23 width: 100%; 24 height: 100px; 25 } 26 </style> 27 28 <body> 29 30 <div id="content"></div> 31 32 <script type="text/javascript"> 33 setup({ explicit_done: true }); 34 35 test(function () { 36 let root = document.documentElement; 37 let body = document.body; 38 let content = document.getElementById('content'); 39 40 // Note: as per the CSSOM spec, the clientWidth of the root element is 41 // "viewport width excluding the size of a rendered scroll bar (if any)" 42 // which does not take scrollbar-gutter into account. 43 // Since no such special case exists for offsetWidth, this means that here 44 // root.clientWidth is actually greater than root.offsetWidth. 45 46 assert_less_than(root.offsetWidth, window.innerWidth, "viewport has gutter"); 47 assert_equals(body.offsetWidth, root.offsetWidth, "body matches root"); 48 assert_equals(body.clientWidth, body.offsetWidth, "body has no gutter"); 49 assert_equals(content.offsetWidth, body.clientWidth, "content matches body"); 50 }, "viewport has gutter, others do not"); 51 52 done(); 53 54 </script> 55 </body>