Mocking entity repository using Moq

If you have a repository class wich enables all CRUD methods on your entity you need a Mocking Library in order to unit test your repository. Without a Mocking Library your unit test will work with real data and that is something you don't want.

Example mocking an Entity Repository

The repository class:

    public class Repository : IRepository
    {
        private ObjectContext database;

        public Repository()
        {
            database = new DWH_IntertEntities();
        }

        public List GetLijst() where T: class
        {
            return database.CreateObjectSet().ToList();
        }
    }

The repository interface

    public interface IRepository
    {
        System.Collections.Generic.List GetLijst() where T : class;
    }

The method wich instantiates the mockup object

        private IRepository Mockup; 
        private void PopulateRepository(Mock mockRepos)
        {
            List filiaalen = new List ();
            
            for (int i = 0; i < 25; i++)
            {
                filiaalen.Add( new Filialen(){ LidNr = i.ToString(), OndernemerNaam = i.ToString()});
            }
            
            mockRepos.Setup(mr => mr.GetLijst()).Returns(filiaalen);
            Mockup = mockRepos.Object;
        }

A litle test method wich shows the mocked data in a datagrid :

        public void Test(DataGridView datagridview)
        {
            var mockRepos = new Mock();
            PopulateRepository(mockRepos);
            datagridview.DataSource = Mockup.GetLijst();
        }