diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/debug/Source-element-01.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/debug/Source-element-01.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,13 @@
+// Source.prototype.element can be an object or undefined.
+
+var g = newGlobal();
+var dbg = new Debugger;
+var gw = dbg.addDebuggee(g);
+g.evaluate("function f(x) { return 2*x; }", {element: { foo: "bar" }});
+var fw = gw.getOwnPropertyDescriptor('f').value;
+assertEq(typeof fw.script.source.element, "object");
+assertEq(fw.script.source.element instanceof Debugger.Object, true);
+assertEq(fw.script.source.element.getOwnPropertyDescriptor("foo").value, "bar");
+g.evaluate("function f(x) { return 2*x; }");
+var fw = gw.getOwnPropertyDescriptor('f').value;
+assertEq(typeof fw.script.source.element, "undefined");