diff -r 000000000000 -r 6474c204b198 browser/devtools/inspector/test/browser_inspector_infobar.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/devtools/inspector/test/browser_inspector_infobar.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,94 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+function test() {
+  waitForExplicitFinish();
+  ignoreAllUncaughtExceptions();
+
+  let doc;
+  let nodes;
+  let cursor;
+  let inspector;
+
+  gBrowser.selectedTab = gBrowser.addTab();
+  gBrowser.selectedBrowser.addEventListener("load", function onload() {
+    gBrowser.selectedBrowser.removeEventListener("load", onload, true);
+    doc = content.document;
+    waitForFocus(setupInfobarTest, content);
+  }, true);
+
+  let style = "body{width:100%;height: 100%} div {position: absolute;height: 100px;width: 500px}#bottom {bottom: 0px}#vertical {height: 100%}#farbottom{bottom: -200px}";
+  let html = "<style>" + style + "</style><div id=vertical></div><div id=top class='class1 class2'></div><div id=bottom></div><div id=farbottom></div>"
+
+  content.location = "data:text/html," + encodeURIComponent(html);
+
+  function setupInfobarTest() {
+    nodes = [
+      {node: doc.querySelector("#top"), position: "bottom", tag: "DIV", id: "#top", classes: ".class1.class2"},
+      {node: doc.querySelector("#vertical"), position: "overlap", tag: "DIV", id: "#vertical", classes: ""},
+      {node: doc.querySelector("#bottom"), position: "top", tag: "DIV", id: "#bottom", classes: ""},
+      {node: doc.querySelector("body"), position: "overlap", tag: "BODY", id: "", classes: ""},
+      {node: doc.querySelector("#farbottom"), position: "top", tag: "DIV", id: "#farbottom", classes: ""},
+    ]
+
+    for (let i = 0; i < nodes.length; i++) {
+      ok(nodes[i].node, "node " + i + " found");
+    }
+
+    openInspector(runTests);
+  }
+
+  function mouseOverContainerToShowHighlighter(node, cb) {
+    let container = getContainerForRawNode(inspector.markup, node);
+    EventUtils.synthesizeMouse(container.tagLine, 2, 2, {type: "mousemove"},
+      inspector.markup.doc.defaultView);
+    executeSoon(cb);
+  }
+
+  function runTests(aInspector) {
+    inspector = aInspector;
+    inspector.selection.setNode(content.document.querySelector("body"));
+    inspector.once("inspector-updated", () => {
+      cursor = 0;
+      executeSoon(function() {
+        mouseOverContainerToShowHighlighter(nodes[0].node, nodeSelected);
+      });
+    });
+  }
+
+  function nodeSelected() {
+    executeSoon(function() {
+      performTest();
+      cursor++;
+      if (cursor >= nodes.length) {
+        finishUp();
+      } else {
+        let node = nodes[cursor].node;
+        mouseOverContainerToShowHighlighter(node, nodeSelected);
+      }
+    });
+  }
+
+  function performTest() {
+    let browser = gBrowser.selectedBrowser;
+    let stack = browser.parentNode;
+
+    let container = stack.querySelector(".highlighter-nodeinfobar-positioner");
+    is(container.getAttribute("position"), nodes[cursor].position, "node " + cursor + ": position matches.");
+
+    let tagNameLabel = stack.querySelector(".highlighter-nodeinfobar-tagname");
+    is(tagNameLabel.textContent, nodes[cursor].tag, "node " + cursor  + ": tagName matches.");
+
+    let idLabel = stack.querySelector(".highlighter-nodeinfobar-id");
+    is(idLabel.textContent, nodes[cursor].id, "node " + cursor  + ": id matches.");
+
+    let classesBox = stack.querySelector(".highlighter-nodeinfobar-classes");
+    is(classesBox.textContent, nodes[cursor].classes, "node " + cursor  + ": classes match.");
+  }
+
+  function finishUp() {
+    doc = nodes = null;
+    gBrowser.removeCurrentTab();
+    finish();
+  }
+}