using System;

using System.IO;

using NUnit.Framework;

​

/*

    Aufgabe:

    Überführen Sie die if-else-Konstrukte in der Methode "Calculator" in eine switch-case-Anweisung, 

    ohne das Verhalten des Programms zu verändern.

*/

​

public class Program

{

    //sollen vorgegebene Tests verwendet werden?

        //Ja -> true

        //Nein -> false

    public static bool useUnitTests = true;

    public static void Calculator() 

    {

        double a = Convert.ToDouble(Console.ReadLine());

        double b = Convert.ToDouble(Console.ReadLine());

        char c = Console.ReadLine()[0];

​

    switch (c)

    {

            case'+':

            Console.WriteLine(a + b);

            break;

            case'-':

            Console.WriteLine(a - b);

            break;

            case'*':

            Console.WriteLine(a * b);

            break;

            case'/':

            // Division durch 0 verhindern

            if (b != 0)

            {

                Console.WriteLine(a / b);

            }

            else

            {

                Console.WriteLine("Division durch 0 ist nicht erlaubt");

            }

            break;

        default:

                Console.WriteLine("Unbekannter Operator");

            break;

    }

    }

    public static void Main(string[] args)

    {

        if(!useUnitTests)

        {

            Calculator();

        }

        else

        {

            //inspired by https://dotnetfiddle.net/6JwsSK - thank you!

            var x = new NUnitLite.AutoRun().Execute(new string[]{"--test:ProgramTests", "--noc", "--timeout=1000", "--noresult", "--noh"});

            Console.WriteLine("");

            Console.WriteLine("----------------------------------------------");

            Console.WriteLine(x==0?"All Test Passed... :¬)": string.Format("{0} tests failed... :¬(", x));

            Console.WriteLine("----------------------------------------------");

        }

    }

}

​

[TestFixture]

public class ProgramTests

{

    [TestCase(5, 10, '+', 15)]

    [TestCase(6, 7, '*', 42)]

    [TestCase(99, 9, '-', 90)]

    [TestCase(100, 100, '/', 1)]

    [Test]

    public void ComputesCorrectly(double a, double b, char c, double expected)

    {

        StringWriter testOutput = new StringWriter();

        StringReader fakeInput = new StringReader(a.ToString() + "\n" + b.ToString() + "\n" + c.ToString() + "\n");

        Console.SetIn(fakeInput);

        Console.SetOut(testOutput);

        Program.Calculator();

        string result = testOutput.ToString().Trim();

        Assert.That(result, Does.Match($"{expected}"),

        $"\nmindeste erwartete Ausgabe: {expected}\n");

    }

}