diff -r 000000000000 -r 6474c204b198 dom/src/json/test/unit/test_decodeFromStream.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/src/json/test/unit/test_decodeFromStream.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,29 @@
+var Ci = Components.interfaces;
+var Cc = Components.classes;
+
+var nativeJSON = Cc["@mozilla.org/dom/json;1"].createInstance(Ci.nsIJSON);
+
+function run_test()
+{
+  function read_file(path)
+  {
+    try
+    {
+      var f = do_get_file(path);
+      var istream = Cc["@mozilla.org/network/file-input-stream;1"].createInstance(Ci.nsIFileInputStream);
+      istream.init(f, -1, -1, false);
+      return nativeJSON.decodeFromStream(istream, istream.available());
+    }
+    finally
+    {
+      istream.close();
+    }
+  }
+
+  var x = read_file("decodeFromStream-01.json");
+  do_check_eq(x["JSON Test Pattern pass3"]["The outermost value"], "must be an object or array.");
+  do_check_eq(x["JSON Test Pattern pass3"]["In this test"], "It is an object.");
+
+  x = read_file("decodeFromStream-small.json");
+  do_check_eq(x.toSource(), "({})", "empty object parsed");
+}