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 /*

  * Call the trap with the handler as the this value, the target as the first

  * argument, the name of the property as the second argument, and the descriptor

  * as the third argument.

  */

 var target = {};

 var called = false;

 var handler = {

     defineProperty: function (target1, name, desc1) {

         assertEq(this, handler);

         assertEq(target1, target);

         assertEq(name, 'foo');

         assertEq(desc1 == desc, false);

         assertEq(desc1.value, 'bar');

         assertEq(desc1.writable, true);

         assertEq(desc1.enumerable, false);

         assertEq(desc1.configurable, true);

         called = true;

     }

 }

 var desc = {

     value: 'bar',

     writable: true,

     enumerable: false,

     configurable: true

 };

 var p = new Proxy(target, handler);

 Object.defineProperty(p, 'foo', desc);

 assertEq(called, true);

 assertEq(Object.isExtensible(target), true);

 assertEq(Object.isExtensible(p), true);

 Object.preventExtensions(target);

 assertEq(Object.isExtensible(target), false);

 assertEq(Object.isExtensible(p), false);