text: (function (global, module) {
  
    var exports = module.exports;
  
    /**
     * Exports.
     */
  
    module.exports = expect;
    expect.Assertion = Assertion;
  
    /**
     * Exports version.
     */
  
    expect.version = '0.1.2';
  
    /**
     * 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;
            }
            name = json.stringify('' + key);
            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: {}}
  );
  