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 /*

  * Any copyright is dedicated to the Public Domain.

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

  */

 var gTestfile = 'proxy-__proto__.js';

 var BUGNUMBER = 770344;

 var summary = "Behavior of __proto__ on proxies";

 print(BUGNUMBER + ": " + summary);

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

  * BEGIN TEST *

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

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

 var protoGetter = protoDesc.get;

 var protoSetter = protoDesc.set;

 function pp(arr)

 {

   return arr.map(function(v) { return "" + v; }).join(", ");

 }

 function testProxy(creator, args, proto)

 {

   print("Now testing behavior for " +

         "Proxy." + creator + "(" + pp(args) + ")");

   var pobj = Proxy[creator].apply(Proxy, args);

   // Check [[Prototype]] before attempted mutation

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

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

   // Attempt [[Prototype]] mutation

   protoSetter.call(pobj, null);

   // Check [[Prototype]] after attempted mutation

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

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

 }

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

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

 var nonNullHandler = { toString: function() { return "non-null handler"; } };

 testProxy("create", [nonNullHandler, nonNullProto], nonNullProto);

 // Proxy object with null [[Prototype]]

 var nullProto = null;

 var nullHandler = { toString: function() { return "null handler"; } };

 testProxy("create", [nullHandler, nullProto], nullProto);

 // Proxy function with [[Call]]

 var callForCallOnly = function () { };

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

 var callOnlyHandler = { toString: function() { return "call-only handler"; } };

 testProxy("createFunction",

           [callOnlyHandler, callForCallOnly], Function.prototype);

 // Proxy function with [[Call]] and [[Construct]]

 var callForCallConstruct = function() { };

 callForCallConstruct.toString = function() { return "call/construct call"; };

 var constructForCallConstruct = function() { };

 constructForCallConstruct.toString =

   function() { return "call/construct construct"; };

 var handlerForCallConstruct =

   { toString: function() { return "call/construct handler"; } };

 testProxy("createFunction",

           [handlerForCallConstruct,

            callForCallConstruct,

            constructForCallConstruct],

           Function.prototype);

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

 if (typeof reportCompare === "function")

   reportCompare(true, true);

 print("Tests complete");