JSTests/test262/test/built-ins/Object/defineProperty/15.2.3.6-4-150.js

// Copyright (c) 2012 Ecma International.  All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.

/*---
es5id: 15.2.3.6-4-150
description: >
    Object.defineProperty - 'O' is an Array, 'name' is the length
    property of 'O', test TypeError is thrown when the [[Value]] field
    of 'desc' is an Object that both toString and valueOf wouldn't
    return primitive value (15.4.5.1 step 3.c)
---*/

var arrObj = [];
var toStringAccessed = false;
var valueOfAccessed = false;
assert.throws(TypeError, function() {
  Object.defineProperty(arrObj, "length", {
    value: {
      toString: function() {
        toStringAccessed = true;
        return {};
      },

      valueOf: function() {
        valueOfAccessed = true;
        return {};
      }
    }
  });
});
assert(toStringAccessed, 'toStringAccessed !== true');
assert(valueOfAccessed, 'valueOfAccessed !== true');