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 /*

  * Any copyright is dedicated to the Public Domain.

  * http://creativecommons.org/licenses/publicdomain/

  */

 var gTestfile = 'proxy-__proto__.js';

 var BUGNUMBER = 950407;

 var summary = "Behavior of __proto__ on ES6 proxies";

 print(BUGNUMBER + ": " + summary);

 /**************

  * BEGIN TEST *

  **************/

 var protoDesc = Object.getOwnPropertyDescriptor(Object.prototype, "__proto__");

 var protoGetter = protoDesc.get;

 var protoSetter = protoDesc.set;

 function testProxy(target, initialProto)

 {

   print("Now testing behavior for new Proxy(" + ("" + target) + ", {})");

   var pobj = new Proxy(target, {});

   // Check [[Prototype]] before attempted mutation

   assertEq(Object.getPrototypeOf(pobj), initialProto);

   assertEq(protoGetter.call(pobj), initialProto);

   // Attempt [[Prototype]] mutation

   protoSetter.call(pobj, null);

   // Check [[Prototype]] after attempted mutation

   assertEq(Object.getPrototypeOf(pobj), null);

   assertEq(protoGetter.call(pobj), null);

   assertEq(Object.getPrototypeOf(target), null);

 }

 // Proxy object with non-null [[Prototype]]

 var nonNullProto = { toString: function() { return "non-null prototype"; } };

 var target = Object.create(nonNullProto);

 testProxy(target, nonNullProto);

 // Proxy object with null [[Prototype]]

 target = Object.create(null);

 target.toString = function() { return "null prototype" };

 testProxy(target, null);

 // Proxy function with [[Call]]

 var callForCallOnly = function () { };

 callForCallOnly.toString = function() { return "callable target"; };

 testProxy(callForCallOnly, Function.prototype);

 /******************************************************************************/

 if (typeof reportCompare === "function")

   reportCompare(true, true);

 print("Tests complete");