using System;

using System.Collections.Generic;

using Moq;

using NUnit.Framework;

using System.Threading.Tasks;

​

public class Program 

{

    public static void Main() 

    {       

        // try catch is only for .net fiddle demo

        try

        {

            // CODE FOR ASSERT EXCEPTIONS IN NUNIT

            // arrange

            var myDependencyMock = new Mock<IMyDependency>();

            var sut = new SystemUnderTest(myDependencyMock.Object);

​

            // act

            // assert

            var ex = Assert.Throws<Exception>(() => sut.DoSomething());

            Assert.True(ex.Message.StartsWith("some error"));

            Console.WriteLine("passed");            

        }

        catch(Exception ex)

        {

            Console.WriteLine("failed " + ex.ToString());

        }

    }

}

​

public class SystemUnderTest

{

    private IMyDependency _myDependency;

    public SystemUnderTest(IMyDependency myDependency)

    {

        _myDependency = myDependency;

    }       

    public string DoSomething()

    {

        if (_myDependency.DoJob() == null)

        {

            throw new Exception("some error");

        }

        else

        {

            return "OK";

        }

    }

}

​

public class MyDependency : IMyDependency

{

    public int? DoJob()

    {

        return null;

    }

}

​

public interface IMyDependency

{

    int? DoJob();

}

​

​