Bug 391899: getItemForID returns an empty nsIUpdateItem if the item doesn't exist. r=robstrong

browser/fuel/src/fuelApplication.js

@@ -527,10 +527,7 @@ Extensions.prototype = {
   },
   
   has : function exts_has(aId) {
-    // getItemForID never returns null for a non-existent id, so we
-    // check the type of the returned update item, which should be
-    // greater than 1 for a valid extension.
-    return !!(this._extmgr.getItemForID(aId).type);
+    return this._extmgr.getItemForID(aId) != null;
   },
   
   get : function exts_get(aId) {

toolkit/mozapps/extensions/public/nsIExtensionManager.idl

@@ -311,7 +311,8 @@ interface nsIExtensionManager : nsISupports
    * Gets a nsIUpdateItem for the item with the specified id.
    * @param   id
    *          The GUID of the item to construct a nsIUpdateItem for.
-   * @returns The nsIUpdateItem representing the item.
+   * @returns The nsIUpdateItem representing the item or null if the item does
+   *          not exist.
    */
   nsIUpdateItem getItemForID(in AString id);
 

toolkit/mozapps/extensions/src/nsExtensionManager.js.in

@@ -6561,6 +6561,9 @@ ExtensionsDataSource.prototype = {
    * @returns The nsIUpdateItem for the id.
    */  
   getItemForID: function(id) {
+    if (!this.visibleItems[id])
+      return null;
+
     var r = getResourceForID(id);
     if (!r)
       return null;

toolkit/mozapps/extensions/test/unit/test_bug391899.js

@@ -0,0 +1,64 @@
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is
+ *      Dave Townsend <dtownsend@oxymoronical.com>.
+ *
+ * Portions created by the Initial Developer are Copyright (C) 2007
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK *****
+ */
+
+const ADDON = "test_bug257155";
+const ID = "bug257155@tests.mozilla.org";
+
+function run_test()
+{
+  // Setup for test
+  createAppInfo("xpcshell@tests.mozilla.org", "XPCShell", "1");
+  startupEM();
+  
+  // Install an extension
+  gEM.installItemFromFile(do_get_addon(ADDON), NS_INSTALL_LOCATION_APPPROFILE);
+  var addon = gEM.getItemForID(ID);
+  do_check_neq(addon, null);
+  do_check_eq(addon.id, ID);
+  restartEM();
+
+  // Check after the restart
+  addon = gEM.getItemForID(ID);
+  do_check_neq(addon, null);
+  do_check_eq(addon.id, ID);
+
+  // Dummy extension should not exist
+  addon = gEM.getItemForID("test-dummy-extension@mozilla.org");
+  do_check_eq(addon, null);
+  shutdownEM();
+}