diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/debug/Object-script-lazy.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/debug/Object-script-lazy.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,43 @@
+// Asking for the script of a Debugger.Object should work, even when lazy
+// functions are involved.
+
+// Note that we never hand out the scripts of non-debuggee functions, and
+// putting a compartment in debug mode automatically de-lazifies all its
+// functions. (This ensures that findScripts works, too.)
+//
+// So here we create a reference to a non-debuggee function, verify that we
+// can't access its interesting properties, make it a debuggee, and verify
+// that everything becomes available.
+
+// Create functions f, g in a non-debuggee compartment.
+var g1 = newGlobal();
+g1.eval('function f() { return "from f"; }');
+g1.eval('function g() { return "from g"; }');
+
+// Create a debuggee compartment with CCWs referring to f and g.
+var g2 = newGlobal();
+var dbg = new Debugger;
+var g2w = dbg.addDebuggee(g2);
+g2.f = g1.f;
+g2.g = g1.g;
+
+// At this point, g1.f should still be a lazy function. Unwrapping a D.O
+// referring to g2's CCW of f should yield a D.O referring to f directly.
+// Asking for that second D.O's script should yield null, because it's not
+// a debuggee.
+var fDO = g2w.getOwnPropertyDescriptor('f').value;
+assertEq(fDO.global, g2w);
+assertEq(fDO.unwrap().global === g2w, false);
+assertEq(fDO.unwrap().script, null);
+
+// Similarly for g1.g, and asking for its parameter names.
+var gDO = g2w.getOwnPropertyDescriptor('g').value;
+assertEq(gDO.global, g2w);
+assertEq(gDO.unwrap().global === g2w, false);
+assertEq(gDO.unwrap().parameterNames, undefined);
+
+// Add g1 as a debuggee, and verify that we can get everything.
+dbg.addDebuggee(g1);
+assertEq(fDO.unwrap().script instanceof Debugger.Script, true);
+assertEq(gDO.unwrap().parameterNames instanceof Array, true);
+