I have to make a method public and virtual to using Moq Setup

Question

I have a repository that has a few private methods in to help in some general stuff that needs to be done within that repository (don't feel you need to read all the code):

public class EFBlogRepository : EFGenericRepository<Blog>, IBlogRepository
{
    public EFBlogRepository( EFDbContext context )
        : base( context )
    {
        this.context = context;
    }

    // Problematic method
    private IQueryable<Blog> PrepareAllBlogsQuery( int page, int amount, string sort, string order, ISearchCriteria searchCriteria )
    {
        var query = context.Blogs
            .Where( x => x.DeletedAt == null );

        ...

        return query;
    }

    public IEnumerable<Blog> GetAllBlogs( int page, int amount, string sort, string order, ISearchCriteria searchCriteria )
    {
        return this.PrepareAllBlogsQuery( page, amount, sort, order, searchCriteria )
            .Skip( ( page - 1 ) * amount )
            .Take( amount );
    }

    public int CountAllBlogs( int page, int amount, string sort, string order, ISearchCriteria searchCriteria )
    {
        return this.PrepareAllBlogsQuery( page, amount, sort, order, searchCriteria )
            .Count();
    }

The problem comes when I try and unit test this...

I have had to make the PrepareAllBlogsQuery public and virtual to get this to work (You just need to read the commented bit):

// Arrange
DateTime now = DateTime.Now;

var mockDbContext = new Mock<EFDbContext>();
var blogRepository = new Mock<EFBlogRepository>(mockDbContext.Object);

IDbSet<Blog> blogDbSet = new FakeDbSet<Blog>();

List<Blog> blogs = new List<Blog> {                 
    new Blog { BlogID = 1, Description = "1", Status = true, PublishDate = now },
    new Blog { BlogID = 2, Description = "2", Status = true, PublishDate = now },
    new Blog { BlogID = 3, Description = "3", Status = true, PublishDate = now },
    new Blog { BlogID = 4, Description = "4", Status = true, PublishDate = now },
    new Blog { BlogID = 5, Description = "5", Status = true, PublishDate = now },
    new Blog { BlogID = 6, Description = "6", Status = true, PublishDate = now },
};

IQueryable<Blog> blogsQueryable = blogs.AsQueryable();

mockDbContext.SetupGet(c => c.Blogs).Returns(blogDbSet);

// This Setup requires my method to be public and virtual :(
blogRepository.SetupGet(c => c.PrepareAllBlogsQuery(2, 2, SortDirection.DESC, null, null)).Returns(blogsQueryable);                 
// Act
List<Blog> result = blogRepository.Object.GetAllBlogs(2, 2, SortDirection.DESC, null, null).ToList();

// Assert     
Assert.AreEqual("3", result[0].Description);

Is there any way around this?

It's not like I even want to test the PrepareAllBlogsQuery method, I just need the mock framework to know what that method returns regardless of its content.

Answer 1

Yes, you should create an interface for your repository which is the thing you mock in your unit test:

public interface IEFBlogRepository
{
    IEnumerable<Blog> GetAllBlogs( int page, int amount, string sort, string order, ISearchCriteria searchCriteria )
}

public class EFBlogRepository : IEFBlogRepository
{
   ...
}

Then in your unit test, you can mock the IEFBlogRepository and you don't need to go anywhere near EF.

var mockRepository = new Mock<IEFBlogRepository>();
mockRepository.Setup(r => r.....);

var thing = new Thing(mockRepository.Object);
thing.DoSomeStuffWhichCallsRepository();

Update

Since it seems you are trying to test EFBlogRepository, you shouldn't be mocking that class, you should use EFBlogRepository itself and just mock its dependencies. You should be able to do something like this to get the correct DB set although I don't know what your FakeDbSet<Blog> actually is:

var blogs = new List<Blog> { ... };
var blogDbSet = new FakeDbSet<Blog>(blogs.AsQueryable());

mockDbContext.SetupGet(c => c.Blogs).Returns(blogDbSet);

The reason Blogs is null for you is because blogDbSet isn't actually configured to return the blogsQueryable

Answer 2

You can have the method declared as internal and expose internals to specific Assembly in your case unit test project's output assembly.

Below attributes needs to be mentioned in the AssemblyInfo.cs of the project being tested. [assembly:InternalsVisibleToAttribute("UnitTestAssemblyName")]

In case of strongly named

[assembly: System.Runtime.CompilerServices.InternalsVisibleTo("BoardEx_BusinessObjects.Tests, PublicKey=0024000004800000940000000602000000240000525341310004000001000100fb3a2")]

there's a similar thread answering the same click here