public async Task GetRelatedEntitiesCountShouldReturnCorrectValues() { var options = new DbContextOptionsBuilder <NeedForCarsDbContext>() .UseInMemoryDatabase("RelatedEntitiesDb_models") .Options; var context = new NeedForCarsDbContext(options); var makesService = new MakesService(context); var modelsService = new ModelsService(context, makesService); var make = new Make { Name = "Make", Description = "Desc" }; await context.Makes.AddAsync(make); var model = new Model { MakeId = make.Id, Name = "Model1", }; await context.Models.AddAsync(model); var generation = new Generation { ModelId = model.Id, Name = "Model1" }; await context.Generations.AddAsync(generation); var engine = new Engine { Name = "engine", MaxHP = 100, FuelType = Models.Enums.FuelType.Diesel, Creator = "creator" }; await context.Engines.AddAsync(engine); var car = new Car { GenerationId = generation.Id, EngineId = engine.Id, Transmission = Models.Enums.Transmission.Automatic, DriveWheel = Models.Enums.DriveWheel.AllWheelDrive, BeginningOfProductionYear = 2000, BeginningOfProductionMonth = 1 }; await context.Cars.AddAsync(car); var user = new NeedForCarsUser { Email = "*****@*****.**", UserName = "******", PasswordHash = "HASHEDPASSWORD", FirstName = "First", LastName = "Last", PhoneNumber = "1234567890" }; await context.Users.AddAsync(user); var userCar = new UserCar { OwnerId = user.Id, CarId = car.Id, Color = "color", ProductionDateYear = 2000, ProductionDateMonth = 1, Mileage = 0 }; await context.UserCars.AddAsync(userCar); await context.SaveChangesAsync(); modelsService.GetRelatedEntitiesCount(model, out int generations, out int cars, out int userCars); Assert.True(generations == 1 && cars == 1 && userCars == 1); }