diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/debug/Object-defineProperty-06.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/debug/Object-defineProperty-06.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,21 @@
+// obj.defineProperty with vague descriptors works like Object.defineProperty
+
+var g = newGlobal();
+var dbg = new Debugger;
+var gw = dbg.addDebuggee(g);
+
+gw.defineProperty("p", {configurable: true, enumerable: true});
+assertEq(g.p, undefined);
+var desc = g.Object.getOwnPropertyDescriptor(g, "p");
+assertEq(desc.configurable, true);
+assertEq(desc.enumerable, true);
+assertEq(desc.value, undefined);
+assertEq(desc.writable, false);
+
+gw.defineProperty("q", {});
+assertEq(g.q, undefined);
+var desc = g.Object.getOwnPropertyDescriptor(g, "q");
+assertEq(desc.configurable, false);
+assertEq(desc.enumerable, false);
+assertEq(desc.value, undefined);
+assertEq(desc.writable, false);