How to do In-Memory repository unit test when working with EF6 with asp.net mvc 4/5

Question

User1183902823 posted

suppose this is my repository

public interface IUserRepository:IDisposable
    {
        IEnumerable<User> GetUsers();
        User GetUserByID(int userId);
        void InsertUser(User user);
        void DeleteUser(int userId);
        void UpdateUser(User user);
        void Save();
    }

public class UserRepository:IUserRepository
    {
        private MVCEntities context;

        public UserRepository(MVCEntities context)
        {
            this.context = context;
        }

        public IEnumerable<User> GetUsers()
        {
            return context.Users.ToList();
        }

        public User GetUserByID(int userId)
        {
            return context.Users.Find(userId);
        }

        public void InsertUser(User user)
        {
            context.Users.Add(user);
        }

        public void DeleteUser(int userId)
        {
            User user = context.Users.Find(userId);
            context.Users.Remove(user);
        }

        public void UpdateUser(User user)
        {
            context.Entry(user).State = EntityState.Modified;
        }

        public void Save()
        {
            context.SaveChanges();
        }

        private bool disposed = false;

        protected virtual void Dispose(bool disposing)
        {
            if (!this.disposed)
            {
                if (disposing)
                {
                    context.Dispose();
                }
            }
            this.disposed = true;
        }

        public void Dispose()
        {
            Dispose(true);
            GC.SuppressFinalize(this);
        }
    }

please provide me guidance with code example that how to do In-Memory repository unit test when working with EF6 with asp.net mvc 4/5.

why people choose sql lite or sql CE as database for EF in-memory test ?
why not they choose sql server local db which reside in app_data folder for EF in-memory test ?

thanks

Answer 1

User617292609 posted

You need to start using mocking frameworks. Moq is a good one:

https://www.nuget.org/packages/Moq/

https://github.com/Moq/moq4/wiki/Quickstart

Here's also an article that might be useful: https://msdn.microsoft.com/en-us/library/dn314429(v=vs.113).aspx

Answer 2

User1400794712 posted

Hi tridip1974,

1) About testing with InMemory, please refer to this article.

https://docs.microsoft.com/en-us/ef/core/miscellaneous/testing/in-memory 

2) SQLite has an in-memory model that allows us to use SQLite to write tests against a relational database, without the overhead of actual database operations. So, it's convenient to use SQLite. Actually, we can also use local db for testing, please refer to this article:

https://guyharwood.co.uk/2013/03/30/entity_framework_tests_with_local_db/ 

Best Regards,

Daisy

Answer 3

User1183902823 posted
@daisy i have one request. I am not a advance developer. here i have given a code for my repository.So would you post code to unit test my repo with in-memory approach. I am using asp.net mvc v4/5.

i saw articles exit for EF core in-memory test but i found none for EF6.

Answer 4

User1183902823 posted

@daisy

i checked your url for in-memory testing.

see this code

protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{
    if (!optionsBuilder.IsConfigured)
    {
        optionsBuilder.UseSqlServer(@"Server=(localdb)\mssqllocaldb;Database=EFProviders.InMemory;Trusted_Connection=True;ConnectRetryCount=0");
    }
}

what is the meaning of the above line? are they using sql server for in-memory test? are they using local db?

[TestMethod]
        public void Add_writes_to_database()
        {
            var options = new DbContextOptionsBuilder<BloggingContext>()
                .UseInMemoryDatabase(databaseName: "Add_writes_to_database")
                .Options;

            // Run the test against one instance of the context
            using (var context = new BloggingContext(options))
            {
                var service = new BlogService(context);
                service.Add("http://sample.com");
            }

            // Use a separate instance of the context to verify correct data was saved to database
            using (var context = new BloggingContext(options))
            {
                Assert.AreEqual(1, context.Blogs.Count());
                Assert.AreEqual("http://sample.com", context.Blogs.Single().Url);
            }
        }

what is the meaning of this line databaseName: "Add_writes_to_database"

what is the meaning of this line

                var service = new BlogService(context);
                service.Add("http://sample.com");

thanks