diff -r 000000000000 -r 6474c204b198 toolkit/devtools/webconsole/test/unit/test_js_property_provider.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/devtools/webconsole/test/unit/test_js_property_provider.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,71 @@
+/* -*- js2-basic-offset: 2; indent-tabs-mode: nil; -*- */
+// Any copyright is dedicated to the Public Domain.
+// http://creativecommons.org/publicdomain/zero/1.0/
+
+"use strict";
+const { devtools } = Components.utils.import("resource://gre/modules/devtools/Loader.jsm", {});
+let JSPropertyProvider = devtools.require("devtools/toolkit/webconsole/utils").JSPropertyProvider;
+
+Components.utils.import("resource://gre/modules/jsdebugger.jsm");
+addDebuggerToGlobal(this);
+
+function run_test() {
+  const testArray = 'var testArray = [\
+    {propA: "A"},\
+    {\
+      propB: "B", \
+      propC: [\
+        {propD: "D"}\
+      ]\
+    },\
+    [\
+      {propE: "E"}\
+    ]\
+  ];'
+
+  const testObject = 'var testObject = {"propA": [{"propB": "B"}]}';
+
+  let sandbox = Components.utils.Sandbox("http://example.com");
+  let dbg = new Debugger;
+  let dbgObject = dbg.addDebuggee(sandbox);
+  Components.utils.evalInSandbox(testArray, sandbox);
+  Components.utils.evalInSandbox(testObject, sandbox);
+
+  let results = JSPropertyProvider(dbgObject, null, "testArray[0].");
+  do_print("Test that suggestions are given for 'foo[n]' where n is an integer.");
+  test_has_result(results, "propA");
+
+  do_print("Test that suggestions are given for multidimensional arrays.");
+  results = JSPropertyProvider(dbgObject, null, "testArray[2][0].");
+  test_has_result(results, "propE");
+
+  do_print("Test that suggestions are not given for index that's out of bounds.");
+  results = JSPropertyProvider(dbgObject, null, "testArray[10].");
+  do_check_null(results);
+
+  do_print("Test that no suggestions are given if an index is not numerical somewhere in the chain.");
+  results = JSPropertyProvider(dbgObject, null, "testArray[0]['propC'][0].");
+  do_check_null(results);
+
+  results = JSPropertyProvider(dbgObject, null, "testObject['propA'][0].");
+  do_check_null(results);
+
+  results = JSPropertyProvider(dbgObject, null, "testArray[0]['propC'].");
+  do_check_null(results);
+
+  results = JSPropertyProvider(dbgObject, null, "testArray[][1].");
+  do_check_null(results);
+}
+
+/**
+ * A helper that ensures (required) results were found.
+ * @param Object aResults
+ *        The results returned by JSPropertyProvider.
+ * @param String aRequiredSuggestion
+ *        A suggestion that must be found from the results.
+ */
+function test_has_result(aResults, aRequiredSuggestion) {
+  do_check_neq(aResults, null);
+  do_check_true(aResults.matches.length > 0);
+  do_check_true(aResults.matches.indexOf(aRequiredSuggestion) !== -1);
+}