michael@0: // obj.hasOwnProperty(id), Object.getOwnPropertyDescriptor(obj, id), and
michael@0: // Object.defineProperty(obj, id, desc) do not look at obj's prototype.
michael@0: 
michael@0: var angryHandler = new Proxy({}, {
michael@0:     has: () => true,
michael@0:     get: (t, id) => {
michael@0:         throw new Error("angryHandler should not be queried (" + id + ")");
michael@0:     }
michael@0: });
michael@0: var angryProto = new Proxy({}, angryHandler);
michael@0: 
michael@0: var obj = Object.create(angryProto, {
michael@0:     // Define hasOwnProperty directly on obj since we are poisoning its
michael@0:     // prototype chain.
michael@0:     hasOwnProperty: {
michael@0:         value: Object.prototype.hasOwnProperty
michael@0:     }
michael@0: });
michael@0: 
michael@0: assertEq(Object.getOwnPropertyDescriptor(obj, "foo"), undefined);
michael@0: assertEq(obj.hasOwnProperty("foo"), false);
michael@0: Object.defineProperty(obj, "foo", {value: 5});
michael@0: assertEq(obj.hasOwnProperty("foo"), true);
michael@0: assertEq(obj.foo, 5);