Unit test to verify that a base class method is called

Question

I have a base class:

public abstract class MyBaseClass
{
    protected virtual void Method1()
    {    
    }
} 

and a derived class:

Answer 1

What you're describing is not a test of your code, but a test of the behavior of the language. That's fine, because it's a good way to ensure that the language behaves the way we think it does. I used to write lots of little console apps when I was learning. I wish I'd known about unit testing then because it's a better way to go about it.

But once you've tested it and confirmed that the language behaves the way you expect, I wouldn't keep writing tests for that. You can just test the behavior of your code.

Here's a real simple example:

public class TheBaseClass
{
    public readonly List Output = new List();

    public virtual void WriteToOutput()
    {
        Output.Add("TheBaseClass");
    }
}

public class TheDerivedClass : TheBaseClass
{
    public override void WriteToOutput()
    {
        Output.Add("TheDerivedClass");
        base.WriteToOutput();
    }
}

Unit test

    [TestMethod]
    public void EnsureDerivedClassCallsBaseClass()
    {
        var testSubject = new TheDerivedClass();
        testSubject.WriteToOutput();
        Assert.IsTrue(testSubject.Output.Contains("TheBaseClass"));
    }