diff -r 000000000000 -r 6474c204b198 browser/devtools/styleinspector/test/browser_styleinspector_csslogic-specificity.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/devtools/styleinspector/test/browser_styleinspector_csslogic-specificity.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,69 @@
+/* vim: set ft=javascript ts=2 et sw=2 tw=80: */
+/* Any copyright is dedicated to the Public Domain.
+ http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Tests that CSS specificity is properly calculated.
+
+const DOMUtils = Cc["@mozilla.org/inspector/dom-utils;1"]
+                   .getService(Ci.inIDOMUtils);
+const TEST_DATA = [
+  {text: "*", expected: 0},
+  {text: "LI", expected: 1},
+  {text: "UL LI", expected: 2},
+  {text: "UL OL + LI", expected: 3},
+  {text: "H1 + [REL=\"up\"]", expected: 257},
+  {text: "UL OL LI.red", expected: 259},
+  {text: "LI.red.level", expected: 513},
+  {text: ".red .level", expected: 512},
+  {text: "#x34y", expected: 65536},
+  {text: "#s12:not(FOO)", expected: 65537},
+  {text: "body#home div#warning p.message", expected: 131331},
+  {text: "* body#home div#warning p.message", expected: 131331},
+  {text: "#footer :not(nav) li", expected: 65538},
+  {text: "bar:nth-child(n)", expected: 257},
+  {text: "li::-moz-list-number", expected: 1},
+  {text: "a:hover", expected: 257}
+];
+
+let test = asyncTest(function*() {
+  yield addTab("data:text/html,Computed view specificity test");
+  createDocument();
+
+  info("Creating a CssLogic instance");
+  let cssLogic = new CssLogic();
+  cssLogic.highlight(content.document.body);
+  let cssSheet = cssLogic.sheets[0];
+  let cssRule = cssSheet.domSheet.cssRules[0];
+  let selectors = CssLogic.getSelectors(cssRule);
+
+  info("Iterating over the test selectors")
+  for (let i = 0; i < selectors.length; i++) {
+    let selectorText = selectors[i];
+    info("Testing selector " + selectorText);
+
+    let selector = new CssSelector(cssRule, selectorText, i);
+    let expected = getExpectedSpecificity(selectorText);
+    let specificity = DOMUtils.getSpecificity(selector.cssRule,
+                                              selector.selectorIndex)
+    is(specificity, expected,
+      'Selector "' + selectorText + '" has a specificity of ' + expected);
+  }
+});
+
+function createDocument() {
+  let doc = content.document;
+  doc.body.innerHTML = getStylesheetText();
+  doc.title = "Computed view specificity test";
+}
+
+function getStylesheetText() {
+  info("Creating the test stylesheet");
+  let text = TEST_DATA.map(i=>i.text).join(",");
+  return '<style type="text/css">' + text + " {color:red;}</style>";
+}
+
+function getExpectedSpecificity(selectorText) {
+  return TEST_DATA.filter(i=>i.text === selectorText)[0].expected;
+}