is this a correct way to test a presenter - asp.net

Question

i'm creating a shopping website using web forms and MVP pattern in a three layered architecture. i also decided to do the validation and type castings inside of presenter class.for testing framework i use NUnit and for my mocks i use NSubstitude. here is my category model class:
//we're doing Dependency injection here.
public abstract class BaseRepository
{
EntityContext context;
public BaseRepository()
{
context = new EntityContext();
}
public EntityContext Context
{
get { return context; }
}
}
public class CategoryRepository : BaseRepository
{
public int Add(long id, string name)
{
Category cat = new Category();
cat.Id = id;
cat.Name = name;
Context.Category.Add(cat);
Context.SaveChanges();
}
}
here is the category presenter:
public class CategoryPresenter : BasePresenter //has nothing but a dependency property to Logger
{
BaseRepository _model;
IView _view;
public CategoryPresenter(IView view)
{
_model = new CategoryRepository();
_view = view;
}
public void Add()
{
//havn't passed the tests yet since i'm not sure if i'm on the correct path.
//whatever validation, loggin and type casting will go here.
_model.Add(_view.CategoryId, _view.CategoryName);
}
}
and here is the test class for the presenter:
[Test]
public void Add_NullId_ThrowException()
{
_view.CategoryId.Returns(p => null);
_view.CategoryName.Returns(p => "test");
Assert.Throws(typeof(InvalidOperationException), _presenter.Add());
}
[Test]
public void Add_EmptyId_ThrowException()
{
_view.CategoryId.Returns(p => "");
_view.CategoryName.Returns(p => "test");
Assert.Throws(typeof(InvalidOperationException), _presenter.Add());
}
[Test]
public void Add_SpaceOnlyId_ThrowException()
{
_view.CategoryId.Returns(p => " ");
_view.CategoryName.Returns(p => "test");
Assert.Throws(typeof(InvalidOperationException), _presenter.Add());
}
[Test]
public void Add_InvalidLowBoundId_ThrowException()
{
_view.CategoryId.Returns(p => "-1");
_view.CategoryName.Returns(p => "test");
Assert.Throws(typeof(InvalidOperationException), _presenter.Add());
}
[Test]
public void Add_InvalidHighBoundId_ThrowException()
{
_view.CategoryId.Returns(p => long.MaxValue.ToString() + "1");
_view.CategoryName.Returns(p => "test");
Assert.Throws(typeof(InvalidOperationException), _presenter.Add());
}
[Test]
public void Add_EmptyName_ThrowException()
{
_view.CategoryId.Returns(p => "1");
_view.CategoryName.Returns(p => "");
Assert.Throws(typeof(InvalidOperationException), _presenter.Add());
}
[Test]
public void Add_NullName_ThrowException()
{
_view.CategoryId.Returns(p => "1");
_view.CategoryName.Returns(p => null);
Assert.Throws(typeof(InvalidOperationException), _presenter.Add());
}
[Test]
public void Add_SpaceOnlyName_ThrowException()
{
_view.CategoryId.Returns(p => "1");
_view.CategoryName.Returns(p => " ");
Assert.Throws(typeof(InvalidOperationException), _presenter.Add());
}
[Test]
public void Add_NumberOnlyName_ThrowException()
{
_view.CategoryId.Returns(p => "1");
_view.CategoryName.Returns(p => "123");
Assert.Throws(typeof(InvalidOperationException), _presenter.Add());
}
am i testing correctly? i mean is this what the test class should look like? i'm i missing something? is this too much? like "you don't need to test emptiness" or any other issues associated with my tests or code? if you notice anything wrong within my whole code and/or architecture i appreciate it if you correct me. thanks!
Update: IView is inherited by a .aspx page. on code behind i simply call the presenter method from inside of a click event that user is triggered by pressing a button. as for memory i havn't gone that far yet. simply stuck on TDD.

Answer 1

I'd remove the validation logic from the application layer (where presenters live) and extract it into the domain layer (where the repositories live).
Then don't do the validation right there in the presenter, but instead have the presenter call the necessary validators.
For unit tests of the presenter you provide validator mock objects to the presenter and verify that the correct validation methods are called for the data.
So you have to test two things:
1) Test if the presenter calls the validators with the data from the view
2) Test the validators on their own
Tests might look like this:
For the presenter (class CategoryPresenterTests):
[Test]
public void Add_CallsTheValidatorWithDataFromTheView()
{
_viewMock.CategoryId.Returns(p => "id");
_viewMock.CategoryName.Returns(p => "name");
_presenter.Add();
_categoryValidatorMock.Verify(x=>x.Validate("id", "name"), Times.Once);
}
[Test]
public void Add_ForwardsValidationExceptions()
{
_viewMock.CategoryId.Returns(p => "id");
_viewMock.CategoryName.Returns(p => "name");
_categoryValidatorMock.Setup(x=>x.Validate(...)).Throws<ValidationException>();
Assert.Throws<ValidationException>(() => _presenter.Add());
}
Note that we don't care about concrete inputs from the view, only that the validator is called with this exact data from the view and that the result (in this case exception or no exception) is passed back.
For the validator (class CategoryValidatorTests. Basically all your current tests go here):
[Test]
public void NullId_ThrowsException() {
string id = null;
string name = "test";
Assert.Throws<ValidationException>(() => _validator.Validate(id, name));
}
Note that I don't know NSubstitutes syntax so the above is pseudo code.. hope you can decipher it :)
Besides that I wouldn't create the repositories within the presenters, instead inject their interfaces through the constructor (like you did with the IView). Then provide mock objects and, like with the validators, verify that they are called correctly by the presenter.
All of the above should allow you to reuse your validation logic outside of the presenters and it'll take some complexity away from the presenters, allowing them to concentrate more on their actual purpose of mediating between model and view and handling workflows.