The Tor Browser / file revision

 // Make sure we behave appropriately when asking for content-disposition

 const Cc = Components.classes;

 const Ci = Components.interfaces;

 const path = "data/test_bug589292.zip";

 function run_test() {

   var ios = Cc["@mozilla.org/network/io-service;1"].

             getService(Ci.nsIIOService);

   var spec = "jar:" + ios.newFileURI(do_get_file(path)).spec + "!/foo.txt";

   var channel = ios.newChannel(spec, null, null);

   instr = channel.open();

   var val;

   try {

     val = channel.contentDisposition;

     do_check_true(false, "The channel has content disposition?!");

   } catch (e) {

     // This is what we want to happen - there's no underlying channel, so no

     // content-disposition header is available

     do_check_true(true, "How are you reading this?!");

   }

 }