public async Task GetAllByCountryIdAsync_ShouldReturnCorrectResult() { MapperInitializer.InitializeMapper(); var context = ApplicationDbContextInMemoryFactory.InitializeContext(); var townRepository = new EfDeletableEntityRepository <Town>(context); var countryRepository = new EfDeletableEntityRepository <Country>(context); var townsService = new TownsService(townRepository); var seeder = new DbContextTestsSeeder(); await seeder.SeedCountriesAsync(context); await seeder.SeedTownsAsync(context); var countryId = await countryRepository.All() .Select(c => c.Id) .FirstOrDefaultAsync(); var result = await townsService.GetAllByCountryIdAsync(countryId); Assert.True(result.ToList().Count == 1, ErrorMessage); }