Solution of the FizzBuzz problem in an OCP dojo

gistfile1.js

describe('fizz buzz',function(){
  var self = this;
  beforeEach(function(){
    var threeChecker = new Checker(3, "Fizz");
    var fiveChecker = new Checker(5, "Buzz");
    var sevenChecker = new Checker(7, "Bang");
    self.fizzBuzzer = new FizzBuzzer([threeChecker, fiveChecker, sevenChecker]);
  });

  it('Default is say the number',function(){
    expect(self.fizzBuzzer.say(1)).toBe('1');
  });
  
  it('If the number is multiple of 3 say Fizz',function(){
    expect(self.fizzBuzzer.say(3)).toBe('Fizz');
  });

  it('If the number is multiple of 5 say Buzz',function(){
    expect(self.fizzBuzzer.say(5)).toBe('Buzz');
  });
  
  it ('FizzBuzz', function(){
    expect(self.fizzBuzzer.say(15)).toBe('FizzBuzz');
  });
  
  it ('Bang', function(){
    expect(self.fizzBuzzer.say(7)).toBe('Bang');
  });
  
  it ('FizzBang', function(){
    expect(self.fizzBuzzer.say(21)).toBe('FizzBang');
  });

});

gistfile2.js

var Checker = (function(Checker){
  Checker = function(number, result) {
    this.number = number;
    this.result = result;
  };
  
  Checker.prototype.check = function(n) {
    return (n%this.number === 0) ? this.result: "";
  };
  return Checker;
}());

function FizzBuzzer(checkers) {
  this.checkers = checkers;
};

FizzBuzzer.prototype.say = function(n) {
  var results = [];
  this.checkers.forEach(function(checker) {
    results.push(checker.check(n));
  });
  
  var result = results.join("");
  if (result.length > 0) {
    return result;
  }
  return n.toString();
};