diff -r 000000000000 -r 6474c204b198 browser/devtools/styleinspector/test/browser_ruleview_livepreview.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/devtools/styleinspector/test/browser_ruleview_livepreview.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,66 @@
+/* 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";
+
+// Test that changes are previewed when editing a property value
+
+// Format
+// {
+//   value : what to type in the field
+//   expected : expected computed style on the targeted element
+// }
+const TEST_DATA = [
+  {value: "inline", expected: "inline"},
+  {value: "inline-block", expected: "inline-block"},
+
+  // Invalid property values should not apply, and should fall back to default
+  {value: "red", expected: "block"},
+  {value: "something", expected: "block"},
+
+  {escape: true, value: "inline", expected: "block"}
+];
+
+let test = asyncTest(function*() {
+  yield addTab("data:text/html,test rule view live preview on user changes");
+
+  let style = '#testid {display:block;}';
+  let styleNode = addStyle(content.document, style);
+  content.document.body.innerHTML = '<div id="testid">Styled Node</div><span>inline element</span>';
+  let testElement = getNode("#testid");
+
+  let {toolbox, inspector, view} = yield openRuleView();
+  yield selectNode(testElement, inspector);
+
+  for (let data of TEST_DATA) {
+    yield testLivePreviewData(data, view, testElement);
+  }
+});
+
+
+function* testLivePreviewData(data, ruleView, testElement) {
+  let idRuleEditor = ruleView.element.children[1]._ruleEditor;
+  let propEditor = idRuleEditor.rule.textProps[0].editor;
+
+  info("Focusing the property value inplace-editor");
+  let editor = yield focusEditableField(propEditor.valueSpan);
+  is(inplaceEditor(propEditor.valueSpan), editor, "The focused editor is the value");
+
+  info("Enter a value in the editor")
+  for (let ch of data.value) {
+    EventUtils.sendChar(ch, ruleView.doc.defaultView);
+  }
+  if (data.escape) {
+    EventUtils.synthesizeKey("VK_ESCAPE", {});
+  } else {
+    EventUtils.synthesizeKey("VK_RETURN", {});
+  }
+
+  yield wait(1);
+
+  // While the editor is still focused in, the display should have changed already
+  is(content.getComputedStyle(testElement).display,
+    data.expected,
+    "Element should be previewed as " + data.expected);
+}