code: function checkArguments () {
      var obj = flag(this, 'object')
        , type = Object.prototype.toString.call(obj);
      this.assert(
          '[object Arguments]' === type
        , 'expected #{this} to be arguments but got ' + type
        , 'expected #{this} to not be arguments'
      );
    }
docs: ### .arguments
  
  Asserts that the target is an arguments object.
  
  function test () {
  expect(arguments).to.be.arguments;
  }
  
  @name arguments
  @alias Arguments
  @api public