Question

I’m using the Unit Of Work Pattern with my data layer.

public interface IUnitOfWork{
    IRepository<Class1> Class1s {get;}
    IRepository<Class2> Class2s {get;}
    ...
}

public interface IRepository<T> where T:class{
    IQueryable<T> GetAll();
}

This is working as expected with my codebase; however, I’m having issues testing this
in my service layer.

public class SomeService{
    private readonly IUnitOfWork uow;
    public SomeService(IUnitOfWork u){
        uow = u;
    }

    public IEnumerable<ViewModel1> GetViewModel(){
        var result1 = uow.Class1s.GetAll();
        var result2 = uow.Class2s.GetAll();
        var query = from r1 in result1
                    from r2 in result2
                       where r1.key == r2.key
                       select new ViewModel1{...};
        return result;
    }
}

(The test) using Moq

[Test]
public void TestMethod(){
    var uow = new Mock<IUnitOfWork>();
    uow.Setup(u => u.Class1s.GetAll()).Returns(new []{ new Class1{...}}.AsQueryable());
    uow.Setup(u => u.Class2s.GetAll()).Returns(new []{ new Class2{...}}.AsQueryable());
    var service = new SomeService(uow.Object);
    var result = service.GetViewModel();
    Assert.AreEqual(1,result.Count());
}

The test is throwing an exception saying that result1 (and result2) are null. I realized this was because I’m not directly instantiating the properties. But I was wondering if there was a way to not have to also mock the properties inside of the mock. If not with Moq then maybe some other mocking framework?

Answer 1

No, Moq won’t help you here. You’ll have to set them manually (although you can mock them aswell):

var class1Mock = new Mock<IRepository<Class1>>();
var class2Mock = new Mock<IRepository<Class2>>();
var uow = new Mock<IUnitOfWork>();
uow.Setup(u => u.Class1).Returns(class1Mock.Object);
uow.Setup(u => u.Class2).Returns(class2Mock.Object);

Note that you’ll now have to do .Setup for GetAll on class1Mock and class2Mock:

class1Mock
    .Setup(c => c.GetAll())
    .Returns(new [] { new Class1 {...} }.AsQueryable());

If you want to have this kind of control over your mocks, there’s no shortcuts I’m afraid.

Note: even though it wont help in your case (since you want direct control over mocks), AutoFixture with Moq is definitely worth checking out in similar scenarios.