diff --git a/xpcom/tests/utils/dirs.js b/xpcom/tests/utils/dirs.js
new file mode 100644
index 000000000000..53ba5b60199d
--- /dev/null
+++ b/xpcom/tests/utils/dirs.js
@@ -0,0 +1,153 @@
+function dumpPathOfProperty(prop)
+{
+    dump(prop +' = ');
+
+    try
+    {
+        var file = dsprops.get(prop, Components.interfaces.nsIFile);
+        dump(file.path + '\n');
+    }
+    catch (ar)
+    {
+        dump('undefined or error \n');
+    }
+}
+
+var dsprogid = "component://netscape/file/directory_service";  // XXX old-style
+var ds = Components.classes[dsprogid].getService();
+var dsprops = ds.QueryInterface(Components.interfaces.nsIProperties);
+
+dump("xpcom locations::\n");
+// XPCOM Locations:
+    dumpPathOfProperty ("xpcom.currentProcess");
+    dumpPathOfProperty ("xpcom.currentProcess.componentRegistry");
+    dumpPathOfProperty ("xpcom.currentProcess.componentDirectory");
+    dumpPathOfProperty ("system.OS_DriveDirectory");
+    dumpPathOfProperty ("system.OS_TemporaryDirectory");
+    dumpPathOfProperty ("system.OS_CurrentProcessDirectory");
+    dumpPathOfProperty ("system.OS_CurrentWorkingDirectory");
+
+dump("Mac locations::\n");
+// Mac
+    dumpPathOfProperty ("system.SystemDirectory");
+    dumpPathOfProperty ("system.DesktopDirectory");
+    dumpPathOfProperty ("system.TrashDirectory");
+    dumpPathOfProperty ("system.StartupDirectory");
+    dumpPathOfProperty ("system.ShutdownDirectory");
+    dumpPathOfProperty ("system.AppleMenuDirectory");
+    dumpPathOfProperty ("system.ControlPanelDirectory");
+    dumpPathOfProperty ("system.ExtensionDirectory");
+    dumpPathOfProperty ("system.FontsDirectory");
+    dumpPathOfProperty ("system.PreferencesDirectory");
+    dumpPathOfProperty ("system.DocumentsDirectory");
+    dumpPathOfProperty ("system.InternetSearchDirectory");
+
+dump("PC locations::\n");
+// PC
+    dumpPathOfProperty ("system.SystemDirectory");
+    dumpPathOfProperty ("system.WindowsDirectory");
+    dumpPathOfProperty ("system.HomeDirectory");
+    dumpPathOfProperty ("system.Desktop");
+    dumpPathOfProperty ("system.Programs");
+    dumpPathOfProperty ("system.Controls");
+    dumpPathOfProperty ("system.Printers");
+    dumpPathOfProperty ("system.Personal");
+    dumpPathOfProperty ("system.Favorites");
+    dumpPathOfProperty ("system.Startup");
+    dumpPathOfProperty ("system.Recent");
+    dumpPathOfProperty ("system.Sendto");
+    dumpPathOfProperty ("system.Bitbucket");
+    dumpPathOfProperty ("system.Startmenu");
+    dumpPathOfProperty ("system.Desktopdirectory");
+    dumpPathOfProperty ("system.Drives");
+    dumpPathOfProperty ("system.Network");
+    dumpPathOfProperty ("system.Nethood");
+    dumpPathOfProperty ("system.Fonts");
+    dumpPathOfProperty ("system.Templates");
+    dumpPathOfProperty ("system.Common_Startmenu");
+    dumpPathOfProperty ("system.Common_Programs");
+    dumpPathOfProperty ("system.Common_Startup");
+    dumpPathOfProperty ("system.Common_Desktopdirectory");
+    dumpPathOfProperty ("system.Appdata");
+    dumpPathOfProperty ("system.Printhood");
+
+dump("Unix locations::\n");
+// Unix
+
+    dumpPathOfProperty ("system.LocalDirectory");
+    dumpPathOfProperty ("system.LibDirectory");
+    dumpPathOfProperty ("system.HomeDirectory");
+
+dump("Beos locations::\n");
+// Beos
+
+    dumpPathOfProperty ("system.SettingsDirectory");
+    dumpPathOfProperty ("system.HomeDirectory");
+    dumpPathOfProperty ("system.DesktopDirectory");
+    dumpPathOfProperty ("system.SystemDirectory");
+
+dump("OS2 locations::\n");
+// OS2
+    dumpPathOfProperty ("system.SystemDirectory");
+
+
+// XPFE locations:
+
+
+// application Directories: 
+    dumpPathOfProperty ("app.res.directory");
+    dumpPathOfProperty ("app.defaults.directory");
+    dumpPathOfProperty ("app.chrome.directory");
+    dumpPathOfProperty ("app.chrome.user.directory");
+    dumpPathOfProperty ("app.plugins.directory");
+
+// application Files:
+
+    dumpPathOfProperty ("app.registry.file.4");
+    dumpPathOfProperty ("app.registry.file.5");
+    dumpPathOfProperty ("app.local.store.file.5");
+    dumpPathOfProperty ("app.history.file.5");
+    dumpPathOfProperty ("app.user.panels.5");
+
+// Preferences:
+
+//   dumpPathOfProperty ("app.prefs.directory.3");
+//   dumpPathOfProperty ("app.prefs.directory.4");
+    dumpPathOfProperty ("app.prefs.directory.5");
+    dumpPathOfProperty ("app.pref.default.directory.5");
+    
+//   dumpPathOfProperty ("app.prefs.file.3");
+//   dumpPathOfProperty ("app.prefs.file.4");
+    dumpPathOfProperty ("app.prefs.file.5");
+
+// Profile:
+
+//   dumpPathOfProperty ("app.profile.user.directory.3");
+//   dumpPathOfProperty ("app.profile.user.directory.4");
+    dumpPathOfProperty ("app.profile.user.directory.5");
+//   dumpPathOfProperty ("app.profile.default.user.directory.3");
+//   dumpPathOfProperty ("app.profile.default.user.directory.4");
+    dumpPathOfProperty ("app.profile.default.user.directory.5");
+//   dumpPathOfProperty ("app.profile.defaults.directory.3");
+//   dumpPathOfProperty ("app.profile.defaults.directory.4");
+    dumpPathOfProperty ("app.profile.defaults.directory.5");
+
+
+
+// Bookmarks:
+
+//   dumpPathOfProperty ("app.bookmark.file.3");
+//   dumpPathOfProperty ("app.bookmark.file.4");
+    dumpPathOfProperty ("app.bookmark.file.5");
+
+// Search
+    dumpPathOfProperty ("app.search.file.5");
+    dumpPathOfProperty ("app.search.directory.5");
+    
+
+// MailNews:
+
+    dumpPathOfProperty ("app.mail.directory.5");
+    dumpPathOfProperty ("app.mail.imap.directory.5");
+    dumpPathOfProperty ("app.mail.news.directory.5");
+    dumpPathOfProperty ("app.mail.messenger.cache.directory.5");
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