public void LessThen1_ThrowException(int n)
        {
            var fizzBuzzService = new FizzBuzzService();
            var ex = Assert.Throws <ArgumentException>(() => {
                fizzBuzzService.GetWord(n);
            });

            Assert.Contains("は1以上としてください", ex.Message);
        }
        public void ReturnsValidString(int n, string word)
        {
            var fizzBuzzService = new FizzBuzzService();

            Assert.Equal(word, fizzBuzzService.GetWord(n));
        }