验证是否使用moq调用抽象方法

Question

I have created an abstract baseclass with some abstract methods:

public abstract class MyBaseClass<T> where T: class, IEntity
{

  public T Load(long id)
  {
     //if in cache continue with cached value 
     //else make use of protected abstract LoadFromContext
  }

  protected abstract T LoadFromContext(long id);
}

now I want to check if the LoadFromContext us called but I get an error : System.ArgumentException: Member FakeCacheRepository.LoadFromContext does not exist

Unittest Moq Setup where FakeCacheRepository is a derived type of MyBaseClass:

Mock<FakeCacheRepository> personRepoMock = new Mock<FakeCacheRepository>();
personRepoMock.Setup(x => x.Load(14)).Returns(new Person() { ID = 14, Name = "Developer14" });
personRepoMock.Protected().Setup("LoadFromContext");

var person = new FakeCacheRepository().Load(14);

Assert.AreEqual("Developer14", person.Name);
personRepoMock.Protected().Verify("LoadFromContext", Times.Once());

What an I doing wrong and are there any good tutorials about moq for a better understanding without having to Google each individual question.

Answer 1

In addition to what TomDoesCode already said:

To use Protected() the way you do, you'll have to use the generic version, since LoadFromContext returns a value ( Person ). Also, you'll have to pass the parameter:

personRepoMock.Protected().Setup<Person>("LoadFromContext", 14L);

Likewise, your Verify has to look like

personRepoMock.Protected().Verify<Person>("LoadFromContext", Times.Once(), 14L);

But even if you would change that, your test would not work. You create a mock of FakeCacheRepository , but then call Load(14) on a new instance of FakeCacheRepository , not on the mock.

You should take a step back and think about what exactly you want to test. If you want to test if FakeCacheRepository calls LoadFromContext from Load , then moq is not the right tool for the job.

Answer 2

The mock object personRepoMock that you setup doesn't appear to be being used by the FakeCacheRepository object person . So your setup and verify aren't used.

However, I don't think that this is the correct approach for testing this, I would just test the FakeCacheRepository class without mocking. Externally, it shouldn't matter that FakeCacheRepository inherits from MyBaseClass , so just test the methods that FakeCacheRepository exposes.

If you want to share code between multiple classes, extract that code into a separate class - inheritance shouldn't be used for sharing code.