public async Task GetHallIdWithValidId() { ApplicationDbContext dbContext = new ApplicationDbContext(new DbContextOptionsBuilder <ApplicationDbContext>() .UseInMemoryDatabase(databaseName: Guid.NewGuid().ToString()).Options); var service = new GalleryService(new EfDeletableEntityRepository <Pic>(dbContext)); await service.AddAsync( "http://www.test.com", "1"); var pic = await dbContext.Pics.FirstOrDefaultAsync(); string hallId = service.GetHallId(pic.Id); Assert.Equal("1", hallId); dbContext.Database.EnsureDeleted(); }