text: (function(global, module) {
  
      var exports = module.exports;
  
      /**
       * Exports.
       */
  
      module.exports = expect;
      expect.Assertion = Assertion;
  
      /**
       * Exports version.
       */
  
      expect.version = '0.3.1';
  
      /**
       * Possible assertion flags.
       */
  
      var flags = {
          not: ['to', 'be', 'have', 'include', 'only']
          , to: ['be', 'have', 'include', 'only', 'not']
          , only: ['have']
          , have: ['own']
          , be: ['an']
      };
  
      function expect(obj) {
          return new Assertion(obj);
      }
  
      /**
       * Constructor
       *
       * @api private
       */
  
      function Assertion(obj, flag, parent) {
          this.obj = obj;
          this.flags = {};
  
          if (undefined != parent) {
              this.flags[flag] = true;
  
              for (var i in parent.flags) {
                  if (parent.flags.hasOwnProperty(i)) {
                      this.flags[i] = true;
                  }
              }
          }
  
          var $flags = flag ? flags[flag] : keys(flags)
                  , self = this;
  
          if ($flags) {
              for (var i = 0, l = $flags.length; i < l; i++) {
                  // avoid recursion
                  if (this.flags[$flags[i]])
                      continue;
  
                  var name = $flags[i]
                          , assertion = new Assertion(this.obj, name, this)
  
                  if ('function' == typeof Assertion.prototype[name]) {
                      // clone the function, make sure we dont touch the prot reference
                      var old = this[name];
                      this[name] = function() {
                          return old.apply(self, arguments);
                      };
  
                      for (var fn in Assertion.prototype) {
                          if (Assertion.prototype.hasOwnProperty(fn) && fn != name) {
                              this[name][fn] = bind(assertion[fn], assertion);
                          }
                      }
                  } else {
                      this[name] = assertion;
                  }
              }
          }
      }
  
      /**
       * Performs an assertion
       *
       * @api private
       */
  
      Assertion.prototype.assert = function(truth, msg, error, expected) {
          var msg = this.flags.not ? error : msg
                  , ok = this.flags.not ? !truth : truth
                  , err;
  
          if (!ok) {
              err = new Error(msg.call(this));
              if (arguments.length > 3) {
                  err.actual = this.obj;
                  err.expected = expected;
                  err.showDiff = true;
              }
              throw err;
          }
  
          this.and = new Assertion(this.obj);
      };
  
      /**
       * Check if the value is truthy
       *
       * @api public
       */
  
      Assertion.prototype.ok = function() {
          this.assert(
                  !!this.obj
                  , function() {
                      return 'expected ' + i(this.obj) + ' to be truthy'
                  }
          , function() {
              return 'expected ' + i(this.obj) + ' to be falsy'
          });
      };
  
      /**
       * Creates an anonymous function which calls fn with arguments.
       *
       * @api public
       */
  
      Assertion.prototype.withArgs = function() {
          expect(this.obj).to.be.a('function');
          var fn = this.obj;
          var args = Array.prototype.slice.call(arguments);
          return expect(function() {
              fn.apply(null, args);
          });
      };
  
      /**
       * Assert that the function throws.
       *
       * @param {Function|RegExp} callback, or regexp to match error string against
       * @api public
       */
  
      Assertion.prototype.throwError =
              Assertion.prototype.throwException = function(fn) {
                  expect(this.obj).to.be.a('function');
  
                  var thrown = false
                          , not = this.flags.not;
  
                  try {
                      this.obj();
                  } catch (e) {
                      if (isRegExp(fn)) {
                          var subject = 'string' == typeof e ? e : e.message;
                          if (not) {
                              expect(subject).to.not.match(fn);
                          } else {
                              expect(subject).to.match(fn);
                          }
                      } else if ('function' == typeof fn) {
                          fn(e);
                      }
                      thrown = true;
                  }
  
                  if (isRegExp(fn) && not) {
                      // in the presence of a matcher, ensure the `not` only applies to
                      // the matching.
                      this.flags.not = false;
                  }
  
                  var name = this.obj.name || 'fn';
                  this.assert(
                          thrown
                          , function() {
                              return 'expected ' + name + ' to throw an exception'
                          }
                  , function() {
                      return 'expected ' + name + ' not to throw an exception'
                  });
              };
  
      /**
       * Checks if the array is empty.
       *
       * @api public
       */
  
      Assertion.prototype.empty = function() {
          var expectation;
  
          if ('object' == typeof this.obj && null !== this.obj && !isArray(this.obj)) {
              if ('number' == typeof this.obj.length) {
                  expectation = !this.obj.length;
              } else {
                  expectation = !keys(this.obj).length;
              }
          } else {
              if ('string' != typeof this.obj) {
                  expect(this.obj).to.be.an('object');
              }
  
              expect(this.obj).to.have.property('length');
              expectation = !this.obj.length;
          }
  
          this.assert(
                  expectation
                  , function() {
                      return 'expected ' + i(this.obj) + ' to be empty'
                  }
          , function() {
              return 'expected ' + i(this.obj) + ' to not be empty'
          });
          return this;
      };
  
      /**
       * Checks if the obj exactly equals another.
       *
       * @api public
       */
  
      Assertion.prototype.be =
              Assertion.prototype.equal = function(obj) {
                  this.assert(
                          obj === this.obj
                          , function() {
                              return 'expected ' + i(this.obj) + ' to equal ' + i(obj)
                          }
                  , function() {
                      return 'expected ' + i(this.obj) + ' to not equal ' + i(obj)
                  });
                  return this;
              };
  
      /**
       * Checks if the obj sortof equals another.
       *
       * @api public
       */
  
      Assertion.prototype.eql = function(obj) {
          this.assert(
                  expect.eql(this.obj, obj)
                  , function() {
                      return 'expected ' + i(this.obj) + ' to sort of equal ' + i(obj)
                  }
          , function() {
              return 'expected ' + i(this.obj) + ' to sort of not equal ' + i(obj)
          }
          , obj);
          return this;
      };
  
      /**
       * Assert within start to finish (inclusive).
       *
       * @param {Number} start
       * @param {Number} finish
       * @api public
       */
  
      Assertion.prototype.within = function(start, finish) {
          var range = start + '..' + finish;
          this.assert(
                  this.obj >= start && this.obj <= finish
                  , function() {
                      return 'expected ' + i(this.obj) + ' to be within ' + range
                  }
          , function() {
              return 'expected ' + i(this.obj) + ' to not be within ' + range
          });
          return this;
      };
  
      /**
       * Assert typeof / instance of
       *
       * @api public
       */
  
      Assertion.prototype.a =
              Assertion.prototype.an = function(type) {
                  if ('string' == typeof type) {
                      // proper english in error msg
                      var n = /^[aeiou]/.test(type) ? 'n' : '';
  
                      // typeof with support for 'array'
                      this.assert(
                              'array' == type ? isArray(this.obj) :
                              'regexp' == type ? isRegExp(this.obj) :
                              'object' == type
                              ? 'object' == typeof this.obj && null !== this.obj
                              : type == typeof this.obj
                              , function() {
                                  return 'expected ' + i(this.obj) + ' to be a' + n + ' ' + type
                              }
                      , function() {
                          return 'expected ' + i(this.obj) + ' not to be a' + n + ' ' + type
                      });
                  } else {
                      // instanceof
                      var name = type.name || 'supplied constructor';
                      this.assert(
                              this.obj instanceof type
                              , function() {
                                  return 'expected ' + i(this.obj) + ' to be an instance of ' + name
                              }
                      , function() {
                          return 'expected ' + i(this.obj) + ' not to be an instance of ' + name
                      });
                  }
  
                  return this;
              };
  
      /**
       * Assert numeric value above _n_.
       *
       * @param {Number} n
       * @api public
       */
  
      Assertion.prototype.greaterThan =
              Assertion.prototype.above = function(n) {
                  this.assert(
                          this.obj > n
                          , function() {
                              return 'expected ' + i(this.obj) + ' to be above ' + n
                          }
                  , function() {
                      return 'expected ' + i(this.obj) + ' to be below ' + n
                  });
                  return this;
              };
  
      /**
       * Assert numeric value below _n_.
       *
       * @param {Number} n
       * @api public
       */
  
      Assertion.prototype.lessThan =
              Assertion.prototype.below = function(n) {
                  this.assert(
                          this.obj < n
                          , function() {
                              return 'expected ' + i(this.obj) + ' to be below ' + n
                          }
                  , function() {
                      return 'expected ' + i(this.obj) + ' to be above ' + n
                  });
                  return this;
              };
  
      /**
       * Assert string value matches _regexp_.
       *
       * @param {RegExp} regexp
       * @api public
       */
  
      Assertion.prototype.match = function(regexp) {
          this.assert(
                  regexp.exec(this.obj)
                  , function() {
                      return 'expected ' + i(this.obj) + ' to match ' + regexp
                  }
          , function() {
              return 'expected ' + i(this.obj) + ' not to match ' + regexp
          });
          return this;
      };
  
      /**
       * Assert property "length" exists and has value of _n_.
       *
       * @param {Number} n
       * @api public
       */
  
      Assertion.prototype.length = function(n) {
          expect(this.obj).to.have.property('length');
          var len = this.obj.length;
          this.assert(
                  n == len
                  , function() {
                      return 'expected ' + i(this.obj) + ' to have a length of ' + n + ' but got ' + len
                  }
          , function() {
              return 'expected ' + i(this.obj) + ' to not have a length of ' + len
          });
          return this;
      };
  
      /**
       * Assert property _name_ exists, with optional _val_.
       *
       * @param {String} name
       * @param {Mixed} val
       * @api public
       */
  
      Assertion.prototype.property = function(name, val) {
          if (this.flags.own) {
              this.assert(
                      Object.prototype.hasOwnProperty.call(this.obj, name)
                      , function() {
                          return 'expected ' + i(this.obj) + ' to have own property ' + i(name)
                      }
              , function() {
                  return 'expected ' + i(this.obj) + ' to not have own property ' + i(name)
              });
              return this;
          }
  
          if (this.flags.not && undefined !== val) {
              if (undefined === this.obj[name]) {
                  throw new Error(i(this.obj) + ' has no property ' + i(name));
              }
          } else {
              var hasProp;
              try {
                  hasProp = name in this.obj
              } catch (e) {
                  hasProp = undefined !== this.obj[name]
              }
  
              this.assert(
                      hasProp
                      , function() {
                          return 'expected ' + i(this.obj) + ' to have a property ' + i(name)
                      }
              , function() {
                  return 'expected ' + i(this.obj) + ' to not have a property ' + i(name)
              });
          }
  
          if (undefined !== val) {
              this.assert(
                      val === this.obj[name]
                      , function() {
                          return 'expected ' + i(this.obj) + ' to have a property ' + i(name)
                                  + ' of ' + i(val) + ', but got ' + i(this.obj[name])
                      }
              , function() {
                  return 'expected ' + i(this.obj) + ' to not have a property ' + i(name)
                          + ' of ' + i(val)
              });
          }
  
          this.obj = this.obj[name];
          return this;
      };
  
      /**
       * Assert that the array contains _obj_ or string contains _obj_.
       *
       * @param {Mixed} obj|string
       * @api public
       */
  
      Assertion.prototype.string =
              Assertion.prototype.contain = function(obj) {
                  if ('string' == typeof this.obj) {
                      this.assert(
                              ~this.obj.indexOf(obj)
                              , function() {
                                  return 'expected ' + i(this.obj) + ' to contain ' + i(obj)
                              }
                      , function() {
                          return 'expected ' + i(this.obj) + ' to not contain ' + i(obj)
                      });
                  } else {
                      this.assert(
                              ~indexOf(this.obj, obj)
                              , function() {
                                  return 'expected ' + i(this.obj) + ' to contain ' + i(obj)
                              }
                      , function() {
                          return 'expected ' + i(this.obj) + ' to not contain ' + i(obj)
                      });
                  }
                  return this;
              };
  
      /**
       * Assert exact keys or inclusion of keys by using
       * the `.own` modifier.
       *
       * @param {Array|String ...} keys
       * @api public
       */
  
      Assertion.prototype.key =
              Assertion.prototype.keys = function($keys) {
                  var str
                          , ok = true;
  
                  $keys = isArray($keys)
                          ? $keys
                          : Array.prototype.slice.call(arguments);
  
                  if (!$keys.length)
                      throw new Error('keys required');
  
                  var actual = keys(this.obj)
                          , len = $keys.length;
  
                  // Inclusion
                  ok = every($keys, function(key) {
                      return ~indexOf(actual, key);
                  });
  
                  // Strict
                  if (!this.flags.not && this.flags.only) {
                      ok = ok && $keys.length == actual.length;
                  }
  
                  // Key string
                  if (len > 1) {
                      $keys = map($keys, function(key) {
                          return i(key);
                      });
                      var last = $keys.pop();
                      str = $keys.join(', ') + ', and ' + last;
                  } else {
                      str = i($keys[0]);
                  }
  
                  // Form
                  str = (len > 1 ? 'keys ' : 'key ') + str;
  
                  // Have / include
                  str = (!this.flags.only ? 'include ' : 'only have ') + str;
  
                  // Assertion
                  this.assert(
                          ok
                          , function() {
                              return 'expected ' + i(this.obj) + ' to ' + str
                          }
                  , function() {
                      return 'expected ' + i(this.obj) + ' to not ' + str
                  });
  
                  return this;
              };
  
      /**
       * Assert a failure.
       *
       * @param {String ...} custom message
       * @api public
       */
      Assertion.prototype.fail = function(msg) {
          var error = function() {
              return msg || "explicit failure";
          }
          this.assert(false, error, error);
          return this;
      };
  
      /**
       * Function bind implementation.
       */
  
      function bind(fn, scope) {
          return function() {
              return fn.apply(scope, arguments);
          }
      }
  
      /**
       * Array every compatibility
       *
       * @see bit.ly/5Fq1N2
       * @api public
       */
  
      function every(arr, fn, thisObj) {
          var scope = thisObj || global;
          for (var i = 0, j = arr.length; i < j; ++i) {
              if (!fn.call(scope, arr[i], i, arr)) {
                  return false;
              }
          }
          return true;
      }
  
      /**
       * Array indexOf compatibility.
       *
       * @see bit.ly/a5Dxa2
       * @api public
       */
  
      function indexOf(arr, o, i) {
          if (Array.prototype.indexOf) {
              return Array.prototype.indexOf.call(arr, o, i);
          }
  
          if (arr.length === undefined) {
              return -1;
          }
  
          for (var j = arr.length, i = i < 0 ? i + j < 0 ? 0 : i + j : i || 0
                  ; i < j && arr[i] !== o; i++)
              ;
  
          return j <= i ? -1 : i;
      }
  
      // https://gist.github.com/1044128/
      var getOuterHTML = function(element) {
          if ('outerHTML' in element)
              return element.outerHTML;
          var ns = "http://www.w3.org/1999/xhtml";
          var container = document.createElementNS(ns, '_');
          var xmlSerializer = new XMLSerializer();
          var html;
          if (document.xmlVersion) {
              return xmlSerializer.serializeToString(element);
          } else {
              container.appendChild(element.cloneNode(false));
              html = container.innerHTML.replace('><', '>' + element.innerHTML + '<');
              container.innerHTML = '';
              return html;
          }
      };
  
      // Returns true if object is a DOM element.
      var isDOMElement = function(object) {
          if (typeof HTMLElement === 'object') {
              return object instanceof HTMLElement;
          } else {
              return object &&
                      typeof object === 'object' &&
                      object.nodeType === 1 &&
                      typeof object.nodeName === 'string';
          }
      };
  
      /**
       * Inspects an object.
       *
       * @see taken from node.js `util` module (copyright Joyent, MIT license)
       * @api private
       */
  
      function i(obj, showHidden, depth) {
          var seen = [];
  
          function stylize(str) {
              return str;
          }
  
          function format(value, recurseTimes) {
              // Provide a hook for user-specified inspect functions.
              // Check that value is an object with an inspect function on it
              if (value && typeof value.inspect === 'function' &&
                      // Filter out the util module, it's inspect function is special
                      value !== exports &&
                      // Also filter out any prototype objects using the circular check.
                      !(value.constructor && value.constructor.prototype === value)) {
                  return value.inspect(recurseTimes);
              }
  
              // Primitive types cannot have properties
              switch (typeof value) {
                  case 'undefined':
                      return stylize('undefined', 'undefined');
  
                  case 'string':
                      var simple = '\'' + json.stringify(value).replace(/^"|"$/g, '')
                              .replace(/'/g, "\\'")
                              .replace(/\\"/g, '"') + '\'';
                      return stylize(simple, 'string');
  
                  case 'number':
                      return stylize('' + value, 'number');
  
                  case 'boolean':
                      return stylize('' + value, 'boolean');
              }
              // For some reason typeof null is "object", so special case here.
              if (value === null) {
                  return stylize('null', 'null');
              }
  
              if (isDOMElement(value)) {
                  return getOuterHTML(value);
              }
  
              // Look up the keys of the object.
              var visible_keys = keys(value);
              var $keys = showHidden ? Object.getOwnPropertyNames(value) : visible_keys;
  
              // Functions without properties can be shortcutted.
              if (typeof value === 'function' && $keys.length === 0) {
                  if (isRegExp(value)) {
                      return stylize('' + value, 'regexp');
                  } else {
                      var name = value.name ? ': ' + value.name : '';
                      return stylize('[Function' + name + ']', 'special');
                  }
              }
  
              // Dates without properties can be shortcutted
              if (isDate(value) && $keys.length === 0) {
                  return stylize(value.toUTCString(), 'date');
              }
  
              // Error objects can be shortcutted
              if (value instanceof Error) {
                  return stylize("[" + value.toString() + "]", 'Error');
              }
  
              var base, type, braces;
              // Determine the object type
              if (isArray(value)) {
                  type = 'Array';
                  braces = ['[', ']'];
              } else {
                  type = 'Object';
                  braces = ['{', '}'];
              }
  
              // Make functions say that they are functions
              if (typeof value === 'function') {
                  var n = value.name ? ': ' + value.name : '';
                  base = (isRegExp(value)) ? ' ' + value : ' [Function' + n + ']';
              } else {
                  base = '';
              }
  
              // Make dates with properties first say the date
              if (isDate(value)) {
                  base = ' ' + value.toUTCString();
              }
  
              if ($keys.length === 0) {
                  return braces[0] + base + braces[1];
              }
  
              if (recurseTimes < 0) {
                  if (isRegExp(value)) {
                      return stylize('' + value, 'regexp');
                  } else {
                      return stylize('[Object]', 'special');
                  }
              }
  
              seen.push(value);
  
              var output = map($keys, function(key) {
                  var name, str;
                  if (value.__lookupGetter__) {
                      if (value.__lookupGetter__(key)) {
                          if (value.__lookupSetter__(key)) {
                              str = stylize('[Getter/Setter]', 'special');
                          } else {
                              str = stylize('[Getter]', 'special');
                          }
                      } else {
                          if (value.__lookupSetter__(key)) {
                              str = stylize('[Setter]', 'special');
                          }
                      }
                  }
                  if (indexOf(visible_keys, key) < 0) {
                      name = '[' + key + ']';
                  }
                  if (!str) {
                      if (indexOf(seen, value[key]) < 0) {
                          if (recurseTimes === null) {
                              str = format(value[key]);
                          } else {
                              str = format(value[key], recurseTimes - 1);
                          }
                          if (str.indexOf('\n') > -1) {
                              if (isArray(value)) {
                                  str = map(str.split('\n'), function(line) {
                                      return '  ' + line;
                                  }).join('\n').substr(2);
                              } else {
                                  str = '\n' + map(str.split('\n'), function(line) {
                                      return '   ' + line;
                                  }).join('\n');
                              }
                          }
                      } else {
                          str = stylize('[Circular]', 'special');
                      }
                  }
                  if (typeof name === 'undefined') {
                      if (type === 'Array' && key.match(/^\d+$/)) {
                          return str;
                      }
                      try {
                          name = json.stringify('' + key);
                      } catch (e) {
                          alert("ddd")
                      }
                      if (name.match(/^"([a-zA-Z_][a-zA-Z_0-9]*)"$/)) {
                          name = name.substr(1, name.length - 2);
                          name = stylize(name, 'name');
                      } else {
                          name = name.replace(/'/g, "\\'")
                                  .replace(/\\"/g, '"')
                                  .replace(/(^"|"$)/g, "'");
                          name = stylize(name, 'string');
                      }
                  }
  
                  return name + ': ' + str;
              });
  
              seen.pop();
  
              var numLinesEst = 0;
              var length = reduce(output, function(prev, cur) {
                  numLinesEst++;
                  if (indexOf(cur, '\n') >= 0)
                      numLinesEst++;
                  return prev + cur.length + 1;
              }, 0);
  
              if (length > 50) {
                  output = braces[0] +
                          (base === '' ? '' : base + '\n ') +
                          ' ' +
                          output.join(',\n  ') +
                          ' ' +
                          braces[1];
  
              } else {
                  output = braces[0] + base + ' ' + output.join(', ') + ' ' + braces[1];
              }
  
              return output;
          }
          return format(obj, (typeof depth === 'undefined' ? 2 : depth));
      }
  
      expect.stringify = i;
  
      function isArray(ar) {
          return Object.prototype.toString.call(ar) === '[object Array]';
      }
  
      function isRegExp(re) {
          var s;
          try {
              s = '' + re;
          } catch (e) {
              return false;
          }
  
          return re instanceof RegExp || // easy case
                  // duck-type for context-switching evalcx case
                  typeof (re) === 'function' &&
                  re.constructor.name === 'RegExp' &&
                  re.compile &&
                  re.test &&
                  re.exec &&
                  s.match(/^\/.*\/[gim]{0,3}$/);
      }
  
      function isDate(d) {
          return d instanceof Date;
      }
  
      function keys(obj) {
          if (Object.keys) {
              return Object.keys(obj);
          }
  
          var keys = [];
  
          for (var i in obj) {
              if (Object.prototype.hasOwnProperty.call(obj, i)) {
                  keys.push(i);
              }
          }
  
          return keys;
      }
  
      function map(arr, mapper, that) {
          if (Array.prototype.map) {
              return Array.prototype.map.call(arr, mapper, that);
          }
  
          var other = new Array(arr.length);
  
          for (var i = 0, n = arr.length; i < n; i++)
              if (i in arr)
                  other[i] = mapper.call(that, arr[i], i, arr);
  
          return other;
      }
  
      function reduce(arr, fun) {
          if (Array.prototype.reduce) {
              return Array.prototype.reduce.apply(
                      arr
                      , Array.prototype.slice.call(arguments, 1)
                      );
          }
  
          var len = +this.length;
  
          if (typeof fun !== "function")
              throw new TypeError();
  
          // no value to return if no initial value and an empty array
          if (len === 0 && arguments.length === 1)
              throw new TypeError();
  
          var i = 0;
          if (arguments.length >= 2) {
              var rv = arguments[1];
          } else {
              do {
                  if (i in this) {
                      rv = this[i++];
                      break;
                  }
  
                  // if array contains no values, no initial value to return
                  if (++i >= len)
                      throw new TypeError();
              } while (true);
          }
  
          for (; i < len; i++) {
              if (i in this)
                  rv = fun.call(null, rv, this[i], i, this);
          }
  
          return rv;
      }
  
      /**
       * Asserts deep equality
       *
       * @see taken from node.js `assert` module (copyright Joyent, MIT license)
       * @api private
       */
  
      expect.eql = function eql(actual, expected) {
          // 7.1. All identical values are equivalent, as determined by ===.
          if (actual === expected) {
              return true;
          } else if ('undefined' != typeof Buffer
                  && Buffer.isBuffer(actual) && Buffer.isBuffer(expected)) {
              if (actual.length != expected.length)
                  return false;
  
              for (var i = 0; i < actual.length; i++) {
                  if (actual[i] !== expected[i])
                      return false;
              }
  
              return true;
  
              // 7.2. If the expected value is a Date object, the actual value is
              // equivalent if it is also a Date object that refers to the same time.
          } else if (actual instanceof Date && expected instanceof Date) {
              return actual.getTime() === expected.getTime();
  
              // 7.3. Other pairs that do not both pass typeof value == "object",
              // equivalence is determined by ==.
          } else if (typeof actual != 'object' && typeof expected != 'object') {
              return actual == expected;
              // If both are regular expression use the special `regExpEquiv` method
              // to determine equivalence.
          } else if (isRegExp(actual) && isRegExp(expected)) {
              return regExpEquiv(actual, expected);
              // 7.4. For all other Object pairs, including Array objects, equivalence is
              // determined by having the same number of owned properties (as verified
              // with Object.prototype.hasOwnProperty.call), the same set of keys
              // (although not necessarily the same order), equivalent values for every
              // corresponding key, and an identical "prototype" property. Note: this
              // accounts for both named and indexed properties on Arrays.
          } else {
              return objEquiv(actual, expected);
          }
      };
  
      function isUndefinedOrNull(value) {
          return value === null || value === undefined;
      }
  
      function isArguments(object) {
          return Object.prototype.toString.call(object) == '[object Arguments]';
      }
  
      function regExpEquiv(a, b) {
          return a.source === b.source && a.global === b.global &&
                  a.ignoreCase === b.ignoreCase && a.multiline === b.multiline;
      }
  
      function objEquiv(a, b) {
          if (isUndefinedOrNull(a) || isUndefinedOrNull(b))
              return false;
          // an identical "prototype" property.
          if (a.prototype !== b.prototype)
              return false;
          //~~~I've managed to break Object.keys through screwy arguments passing.
          //   Converting to array solves the problem.
          if (isArguments(a)) {
              if (!isArguments(b)) {
                  return false;
              }
              a = pSlice.call(a);
              b = pSlice.call(b);
              return expect.eql(a, b);
          }
          try {
              var ka = keys(a),
                      kb = keys(b),
                      key, i;
          } catch (e) {//happens when one is a string literal and the other isn't
              return false;
          }
          // having the same number of owned properties (keys incorporates hasOwnProperty)
          if (ka.length != kb.length)
              return false;
          //the same set of keys (although not necessarily the same order),
          ka.sort();
          kb.sort();
          //~~~cheap key test
          for (i = ka.length - 1; i >= 0; i--) {
              if (ka[i] != kb[i])
                  return false;
          }
          //equivalent values for every corresponding key, and
          //~~~possibly expensive deep test
          for (i = ka.length - 1; i >= 0; i--) {
              key = ka[i];
              if (!expect.eql(a[key], b[key]))
                  return false;
          }
          return true;
      }
  
      var json = (function() {
          "use strict";
  
          if ('object' == typeof JSON && JSON.parse && JSON.stringify) {
              return {
                  parse: nativeJSON.parse
                  , stringify: nativeJSON.stringify
              }
          }
  
          var JSON = {};
  
          function f(n) {
              // Format integers to have at least two digits.
              return n < 10 ? '0' + n : n;
          }
  
          function date(d, key) {
              return isFinite(d.valueOf()) ?
                      d.getUTCFullYear() + '-' +
                      f(d.getUTCMonth() + 1) + '-' +
                      f(d.getUTCDate()) + 'T' +
                      f(d.getUTCHours()) + ':' +
                      f(d.getUTCMinutes()) + ':' +
                      f(d.getUTCSeconds()) + 'Z' : null;
          }
  
          var cx = /[\u0000\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
                  escapable = /[\\\"\x00-\x1f\x7f-\x9f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
                  gap,
                  indent,
                  meta = {// table of character substitutions
                      '\b': '\\b',
                      '\t': '\\t',
                      '\n': '\\n',
                      '\f': '\\f',
                      '\r': '\\r',
                      '"': '\\"',
                      '\\': '\\\\'
                  },
          rep;
  
  
          function quote(string) {
  
              // If the string contains no control characters, no quote characters, and no
              // backslash characters, then we can safely slap some quotes around it.
              // Otherwise we must also replace the offending characters with safe escape
              // sequences.
  
              escapable.lastIndex = 0;
              return escapable.test(string) ? '"' + string.replace(escapable, function(a) {
                  var c = meta[a];
                  return typeof c === 'string' ? c :
                          '\\u' + ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
              }) + '"' : '"' + string + '"';
          }
  
  
          function str(key, holder) {
  
              // Produce a string from holder[key].
  
              var i, // The loop counter.
                      k, // The member key.
                      v, // The member value.
                      length,
                      mind = gap,
                      partial,
                      value = holder[key];
  
              // If the value has a toJSON method, call it to obtain a replacement value.
  
              if (value instanceof Date) {
                  value = date(key);
              }
  
              // If we were called with a replacer function, then call the replacer to
              // obtain a replacement value.
  
              if (typeof rep === 'function') {
                  value = rep.call(holder, key, value);
              }
  
              // What happens next depends on the value's type.
  
              switch (typeof value) {
                  case 'string':
                      return quote(value);
  
                  case 'number':
  
                      // JSON numbers must be finite. Encode non-finite numbers as null.
  
                      return isFinite(value) ? String(value) : 'null';
  
                  case 'boolean':
                  case 'null':
  
                      // If the value is a boolean or null, convert it to a string. Note:
                      // typeof null does not produce 'null'. The case is included here in
                      // the remote chance that this gets fixed someday.
  
                      return String(value);
  
                      // If the type is 'object', we might be dealing with an object or an array or
                      // null.
  
                  case 'object':
  
                      // Due to a specification blunder in ECMAScript, typeof null is 'object',
                      // so watch out for that case.
  
                      if (!value) {
                          return 'null';
                      }
  
                      // Make an array to hold the partial results of stringifying this object value.
  
                      gap += indent;
                      partial = [];
  
                      // Is the value an array?
  
                      if (Object.prototype.toString.apply(value) === '[object Array]') {
  
                          // The value is an array. Stringify every element. Use null as a placeholder
                          // for non-JSON values.
  
                          length = value.length;
                          for (i = 0; i < length; i += 1) {
                              partial[i] = str(i, value) || 'null';
                          }
  
                          // Join all of the elements together, separated with commas, and wrap them in
                          // brackets.
  
                          v = partial.length === 0 ? '[]' : gap ?
                                  '[\n' + gap + partial.join(',\n' + gap) + '\n' + mind + ']' :
                                  '[' + partial.join(',') + ']';
                          gap = mind;
                          return v;
                      }
  
                      // If the replacer is an array, use it to select the members to be stringified.
  
                      if (rep && typeof rep === 'object') {
                          length = rep.length;
                          for (i = 0; i < length; i += 1) {
                              if (typeof rep[i] === 'string') {
                                  k = rep[i];
                                  v = str(k, value);
                                  if (v) {
                                      partial.push(quote(k) + (gap ? ': ' : ':') + v);
                                  }
                              }
                          }
                      } else {
  
                          // Otherwise, iterate through all of the keys in the object.
  
                          for (k in value) {
                              if (Object.prototype.hasOwnProperty.call(value, k)) {
                                  v = str(k, value);
                                  if (v) {
                                      partial.push(quote(k) + (gap ? ': ' : ':') + v);
                                  }
                              }
                          }
                      }
  
                      // Join all of the member texts together, separated with commas,
                      // and wrap them in braces.
  
                      v = partial.length === 0 ? '{}' : gap ?
                              '{\n' + gap + partial.join(',\n' + gap) + '\n' + mind + '}' :
                              '{' + partial.join(',') + '}';
                      gap = mind;
                      return v;
              }
          }
  
          // If the JSON object does not yet have a stringify method, give it one.
  
          JSON.stringify = function(value, replacer, space) {
  
              // The stringify method takes a value and an optional replacer, and an optional
              // space parameter, and returns a JSON text. The replacer can be a function
              // that can replace values, or an array of strings that will select the keys.
              // A default replacer method can be provided. Use of the space parameter can
              // produce text that is more easily readable.
  
              var i;
              gap = '';
              indent = '';
  
              // If the space parameter is a number, make an indent string containing that
              // many spaces.
  
              if (typeof space === 'number') {
                  for (i = 0; i < space; i += 1) {
                      indent += ' ';
                  }
  
                  // If the space parameter is a string, it will be used as the indent string.
  
              } else if (typeof space === 'string') {
                  indent = space;
              }
  
              // If there is a replacer, it must be a function or an array.
              // Otherwise, throw an error.
  
              rep = replacer;
              if (replacer && typeof replacer !== 'function' &&
                      (typeof replacer !== 'object' ||
                              typeof replacer.length !== 'number')) {
                  throw new Error('JSON.stringify');
              }
  
              // Make a fake root object containing our value under the key of ''.
              // Return the result of stringifying the value.
  
              return str('', {'': value});
          };
  
          // If the JSON object does not yet have a parse method, give it one.
  
          JSON.parse = function(text, reviver) {
              // The parse method takes a text and an optional reviver function, and returns
              // a JavaScript value if the text is a valid JSON text.
  
              var j;
  
              function walk(holder, key) {
  
                  // The walk method is used to recursively walk the resulting structure so
                  // that modifications can be made.
  
                  var k, v, value = holder[key];
                  if (value && typeof value === 'object') {
                      for (k in value) {
                          if (Object.prototype.hasOwnProperty.call(value, k)) {
                              v = walk(value, k);
                              if (v !== undefined) {
                                  value[k] = v;
                              } else {
                                  delete value[k];
                              }
                          }
                      }
                  }
                  return reviver.call(holder, key, value);
              }
  
  
              // Parsing happens in four stages. In the first stage, we replace certain
              // Unicode characters with escape sequences. JavaScript handles many characters
              // incorrectly, either silently deleting them, or treating them as line endings.
  
              text = String(text);
              cx.lastIndex = 0;
              if (cx.test(text)) {
                  text = text.replace(cx, function(a) {
                      return '\\u' +
                              ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
                  });
              }
  
              // In the second stage, we run the text against regular expressions that look
              // for non-JSON patterns. We are especially concerned with '()' and 'new'
              // because they can cause invocation, and '=' because it can cause mutation.
              // But just to be safe, we want to reject all unexpected forms.
  
              // We split the second stage into 4 regexp operations in order to work around
              // crippling inefficiencies in IE's and Safari's regexp engines. First we
              // replace the JSON backslash pairs with '@' (a non-JSON character). Second, we
              // replace all simple value tokens with ']' characters. Third, we delete all
              // open brackets that follow a colon or comma or that begin the text. Finally,
              // we look to see that the remaining characters are only whitespace or ']' or
              // ',' or ':' or '{' or '}'. If that is so, then the text is safe for eval.
  
              if (/^[\],:{}\s]*$/
                      .test(text.replace(/\\(?:["\\\/bfnrt]|u[0-9a-fA-F]{4})/g, '@')
                              .replace(/"[^"\\\n\r]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g, ']')
                              .replace(/(?:^|:|,)(?:\s*\[)+/g, ''))) {
  
                  // In the third stage we use the eval function to compile the text into a
                  // JavaScript structure. The '{' operator is subject to a syntactic ambiguity
                  // in JavaScript: it can begin a block or an object literal. We wrap the text
                  // in parens to eliminate the ambiguity.
  
                  j = eval('(' + text + ')');
  
                  // In the optional fourth stage, we recursively walk the new structure, passing
                  // each name/value pair to a reviver function for possible transformation.
  
                  return typeof reviver === 'function' ?
                          walk({'': j}, '') : j;
              }
  
              // If the text is not JSON parseable, then a SyntaxError is thrown.
  
              throw new SyntaxError('JSON.parse');
          };
  
          return JSON;
      })();
  
      if ('undefined' != typeof window) {
          window.expect = module.exports;
      }
  
  })(
          this
          , 'undefined' != typeof module ? module : {exports: {}}
  );