diff -r 000000000000 -r 6474c204b198 toolkit/devtools/gcli/commands/tools.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/devtools/gcli/commands/tools.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,87 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const { Cc, Ci, Cu } = require("chrome");
+const Services = require("Services");
+const { OS } = require("resource://gre/modules/osfile.jsm");
+const { devtools } = require("resource://gre/modules/devtools/Loader.jsm");
+const gcli = require("gcli/index");
+
+const BRAND_SHORT_NAME = Cc["@mozilla.org/intl/stringbundle;1"]
+                           .getService(Ci.nsIStringBundleService)
+                           .createBundle("chrome://branding/locale/brand.properties")
+                           .GetStringFromName("brandShortName");
+
+exports.items = [
+  {
+    name: "tools",
+    description: gcli.lookupFormat("toolsDesc2", [ BRAND_SHORT_NAME ]),
+    manual: gcli.lookupFormat("toolsManual2", [ BRAND_SHORT_NAME ]),
+    get hidden() gcli.hiddenByChromePref(),
+  },
+  {
+    name: "tools srcdir",
+    description: gcli.lookup("toolsSrcdirDesc"),
+    manual: gcli.lookupFormat("toolsSrcdirManual2", [ BRAND_SHORT_NAME ]),
+    get hidden() gcli.hiddenByChromePref(),
+    params: [
+      {
+        name: "srcdir",
+        type: "string" /* {
+          name: "file",
+          filetype: "directory",
+          existing: "yes"
+        } */,
+        description: gcli.lookup("toolsSrcdirDir")
+      }
+    ],
+    returnType: "string",
+    exec: function(args, context) {
+      let clobber = OS.Path.join(args.srcdir, "CLOBBER");
+      return OS.File.exists(clobber).then(function(exists) {
+        if (exists) {
+          let str = Cc["@mozilla.org/supports-string;1"]
+                      .createInstance(Ci.nsISupportsString);
+          str.data = args.srcdir;
+          Services.prefs.setComplexValue("devtools.loader.srcdir",
+                                         Ci.nsISupportsString, str);
+          devtools.reload();
+
+          let msg = gcli.lookupFormat("toolsSrcdirReloaded", [ args.srcdir ]);
+          throw new Error(msg);
+        }
+
+        return gcli.lookupFormat("toolsSrcdirNotFound", [ args.srcdir ]);
+      });
+    }
+  },
+  {
+    name: "tools builtin",
+    description: gcli.lookup("toolsBuiltinDesc"),
+    manual: gcli.lookup("toolsBuiltinManual"),
+    get hidden() gcli.hiddenByChromePref(),
+    returnType: "string",
+    exec: function(args, context) {
+      Services.prefs.clearUserPref("devtools.loader.srcdir");
+      devtools.reload();
+      return gcli.lookup("toolsBuiltinReloaded");
+    }
+  },
+  {
+    name: "tools reload",
+    description: gcli.lookup("toolsReloadDesc"),
+    get hidden() {
+      return gcli.hiddenByChromePref() ||
+             !Services.prefs.prefHasUserValue("devtools.loader.srcdir");
+    },
+
+    returnType: "string",
+    exec: function(args, context) {
+      devtools.reload();
+      return gcli.lookup("toolsReloaded2");
+    }
+  }
+];