Unit testing and volume of objects - how to test private / internal methods, etc.?

Question

Say I have a project that is a class library. I have a class in this library, and this class has some methods that are used only inside the class. Like this:

public class MyClass
{
  public void MyPublicMethod
  {
    int k

    // do something ...

    int z = MyInternalMethod(k);
    // do something else ...

  }

  internal int MyInternalMethod(int i)
  {
        // do something ...

  }
}

Now I want to write unit tests for these methods. I would create a Unit Tests project, reference nunit, and write something like this

[TestFixture]
public class UnitTests
{
  private MyClass myClass;

  [SetUp]
  public void SetupTest
  {
    myClass = new MyClass();
  }

  [Test]
  public void TestMyInternalMethod
  {
    int z = 100;
    int k = myClass.MyInternalMethod(z); //CAN NOT DO THIS!
    Assert.AreEqual(k, 100000);
  }

  [TearDown]
  public void TearDown
  {
    myClass = null;
  }
}

Of course, I cannot do this due to the scope of MyInternalMethod. What would be the right way to deal with this situation?

Answer 1

, InternalsVisibleToAttribute.

Answer 2

, , , ? . , (java) unit test. , .

Answer 3

( , , , ).

, , !

Answer 4

:

http://www.codeproject.com/KB/cs/testnonpublicmembers.aspx

- , - . , , , . , . , , , . .

Answer 5

, , API. , , .

Answer 6

: - , . - , , , .

, TDD, spring, , .

Answer 7

Visual Studio . , MSDN. , VS2005 unit test. , , . VS2008 unit test. NUnit, , . . , - / .

Answer 8

, . , . , , .

( ). , , , .

, , , ; , code-and-data-together = object object-and-doc-comments = documented-object. : code-and-data-and-test-and-doc-comments-together = cohesive-unit.

.

Answer 9

. , unit test "" . - . , , . , .

public static class ReflectionHelper
{
    public static object RunStaticMethod<TInstance>(string methodName, params object[] methodParams)
    {
        var methodType = BindingFlags.Static | BindingFlags.Public | BindingFlags.NonPublic;
        return RunMethod<TInstance>(null, methodName, methodType, methodParams);
    }

    public static object RunInstanceMethod<TInstance>(this TInstance instance, string methodName, params object[] methodParams)
    {
        var methodType = BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic;
        return RunMethod<TInstance>(instance, methodName, methodType, methodParams);
    }

    private static object RunMethod<TInstance>(object instance, string methodName, BindingFlags methodType, params object[] methodParams)
    {
        var instanceType = typeof(TInstance);
        var method = instanceType.GetMethod(methodName, methodType);
        if (method == null)
        {
            throw new ArgumentException(string.Format("There is no method '{0}' for type '{1}'.", methodName, instanceType));
        }

        var result = method.Invoke(instance, methodParams);

        return result;
    }
}

,

public class User
{
    public string FirstName { get; set; }
    public string LastName { get; set; }

    internal string GetPrettyName()
    {
        return string.Concat(FirstName, " ", LastName);
    }

    static internal int GetSystemId(string userName)
    {
        // some magic here
        return 13;
    }
}

var user = new User { FirstName = "Peter", LastName = "Gibbons" };

var name = user.RunInstanceMethod("GetPrettyName");
Assert.That(name, Is.EqualTo("Peter Gibbons"));

var id = ReflectionHelper.RunStaticMethod<User>("GetSystemId", "tester");
Assert.That(id, Is.EqualTo(13));

Answer 10

, , . : -, , , -, , , .

Not everyone agrees with this approach (see this SO question that I asked earlier), but so far I have not found or did not have any shortcomings in it pointed me out. I do unit tests in a way to go after 4 or 5 years.

#if UNITTEST
using NUnit.Framework;
#endif

public class MyBlackMagic
{
    private int DoMagic()
    {
        return 1;
    }

    #if UNITTEST

    [TestFixture]
    public class MyBlackMagicUnitTest
    {
         [TestFixtureSetUp]
         public void Init()
         {
             log4net.Config.BasicConfigurator.Configure();
         }

         [Test]
         public void DoMagicTest()
         {
             Console.WriteLine(System.Reflection.MethodBase.GetCurrentMethod().Name);
             Assert.IsTrue(DoMagic() == 1, "You are not a real magician!");
         }
     }

     #endif
 }