layout/style/test/test_compute_data_with_start_struct.html

   1 <!DOCTYPE HTML>
   2 <html>
   3 <head>
   4   <title>Test for correct handling of aStartStruct parameter to nsRuleNode::Compute*Data</title>
   5   <script src="/tests/SimpleTest/SimpleTest.js"></script>
   6   <script type="text/javascript" src="property_database.js"></script>
   7   <style type="text/css" id="stylesheet"></style>
   8   <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
   9 </head>
  10 <body>
  11 <a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=216456">Mozilla Bug 216456</a>
  12 <p id="display">
  13   <span id="base"></span>
  14   <span id="test"></span>
  15 </p>
  16 <div id="content" style="display: none">
  17
  18 </div>
  19 <pre id="test">
  20 <script class="testbody" type="text/javascript">
  21
  22 /**
  23  * The purpose of this test was to test that in the old style system
  24  * the nsRuleNode::Compute*Data functions were written correctly.
  25  * In particular, in these functions, when the specified value of a
  26  * property had unit eCSSUnit_Null, touching the computed data is
  27  * forbidden. This is because we sometimes would stop walking up the
  28  * rule tree when we find computed data for an initial subsequence of
  29  * our rules (i.e., an ancestor rule node) that we can use as a starting
  30  * point (aStartStruct) for the computation for the current rule node.
  31  *
  32  * However, we don't cache style structs in the rule tree in the current
  33  * style system code, and property cascading no longer relies on hand
  34  * written functions, so this particular failure mode isn't as likely to
  35  * happen.
  36  */
  37
  38 var gStyleSheet = document.getElementById("stylesheet").sheet;
  39 var gRule1 = gStyleSheet.cssRules[gStyleSheet.insertRule("#base, #test {}", gStyleSheet.cssRules.length)];
  40 var gRule2 = gStyleSheet.cssRules[gStyleSheet.insertRule("#test {}", gStyleSheet.cssRules.length)];
  41
  42 var gBase = getComputedStyle(document.getElementById("base"), "");
  43 var gTest = getComputedStyle(document.getElementById("test"), "");
  44
  45 function test_property(prop, lower_set, higher_set) {
  46   var info = gCSSProperties[prop];
  47   if (info.subproperties || info.logical)
  48     return;
  49
  50   gRule1.style.setProperty(prop, info[lower_set][0]);
  51   gRule2.style.setProperty(prop, info[higher_set][0]);
  52
  53   if ("prerequisites" in info) {
  54     for (var prereq in info.prerequisites) {
  55       gRule2.style.setProperty(prereq, info.prerequisites[prereq], "");
  56     }
  57   }
  58
  59   gBase.getPropertyValue(prop);
  60   var higher_set_val = gTest.getPropertyValue(prop);
  61   gRule2.style.setProperty(prop, info[lower_set][0], "");
  62   var lower_set_val = gTest.getPropertyValue(prop);
  63   isnot(higher_set_val, lower_set_val, "initial and other values of " + prop + " are different");
  64
  65   gRule2.style.removeProperty(prop);
  66   is(gTest.getPropertyValue(prop), lower_set_val, prop + " is not touched when its value comes from aStartStruct");
  67
  68   gRule1.style.removeProperty(prop);
  69   if ("prerequisites" in info) {
  70     for (var prereq in info.prerequisites) {
  71       gRule2.style.removeProperty(prereq);
  72     }
  73   }
  74 }
  75
  76 function round(lower_set, higher_set) {
  77   for (var prop in gCSSProperties)
  78     test_property(prop, lower_set, higher_set);
  79 }
  80
  81 round("other_values", "initial_values");
  82 round("initial_values", "other_values");
  83
  84 </script>
  85 </pre>
  86 </body>
  87 </html>