public async Task CheckRoomsShouldWorkCorrectlyIfTypeOfRoomIsAll() { //Arange var options = new DbContextOptionsBuilder <ApplicationDbContext>() .UseInMemoryDatabase(databaseName: Guid.NewGuid().ToString()).Options; var db = new ApplicationDbContext(options); var config = new MapperConfiguration(cfg => { cfg.AddProfile <ApplicationProfile>(); }); var mapper = new Mapper(config); var roomService = new RoomService(db, mapper); //Act var room = new Room { Adults = 1, CheckIn = new DateTime(2020, 12, 20), CheckOut = new DateTime(2020, 12, 21), Image = "no image", Description = "no description", Price = 5, RoomCount = 5, RoomType = RoomType.Single, }; db.Rooms.Add(room); await db.SaveChangesAsync(); var models = roomService.CheckRooms(new DateTime(2020, 12, 22), new DateTime(2020, 12, 24), "1", "All"); //assert Assert.True(models.Count() == 1); }