private static bool MainMenu()
        {
            Console.Clear();
            Console.WriteLine("Welcome to the Introduction to Unit Testing");
            Console.WriteLine("We will be running a simple calculator");
            Console.WriteLine("Enter an option:");
            Console.WriteLine("1) Addition");
            Console.WriteLine("2) Subtraction");
            Console.WriteLine("3) Exit");
            Console.Write("\r\nSelect an option: ");

            switch (Console.ReadLine())
            {
            case "1":
                Addition.AddNumbers();
                return(true);

            case "2":
                Console.WriteLine("No exist yet");
                return(true);

            case "3":
                return(false);

            default:
                return(true);
            }
        }
        public void AdditionOperationSumsCorrectly(int number1, int number2, int expectedSum)
        {
            var additionCalculator = new Addition();
            var calculatedSum      = additionCalculator.AddNumbers(number1, number2);

            Assert.AreEqual(expectedSum, calculatedSum);
        }
        public void CheckAdditionMethod()
        {
            Addition additionNumber = new Addition();

            int expectedResult = 9;
            int actualResult   = additionNumber.AddNumbers(5, 4);

            Assert.AreEqual(expectedResult, actualResult);
        }
 public int Add(int number1, int number2)
 {
     return(_addition.AddNumbers(number1, number2));
 }