var Cc = Components.classes; var Ci = Components.interfaces; function run_test() { var f = Cc["@mozilla.org/file/directory_service;1"]. getService(Ci.nsIProperties).get("CurProcD", Ci.nsIFile); var terminated = false; for (var i = 0; i < 100; i++) { if (f == null) { terminated = true; break; } f = f.parent; } do_check_true(terminated); }