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 // obj.hasOwnProperty(id), Object.getOwnPropertyDescriptor(obj, id), and

 // Object.defineProperty(obj, id, desc) do not look at obj's prototype.

 var angryHandler = new Proxy({}, {

     has: () => true,

     get: (t, id) => {

         throw new Error("angryHandler should not be queried (" + id + ")");

     }

 });

 var angryProto = new Proxy({}, angryHandler);

 var obj = Object.create(angryProto, {

     // Define hasOwnProperty directly on obj since we are poisoning its

     // prototype chain.

     hasOwnProperty: {

         value: Object.prototype.hasOwnProperty

     }

 });

 assertEq(Object.getOwnPropertyDescriptor(obj, "foo"), undefined);

 assertEq(obj.hasOwnProperty("foo"), false);

 Object.defineProperty(obj, "foo", {value: 5});

 assertEq(obj.hasOwnProperty("foo"), true);

 assertEq(obj.foo, 5);