public async Task AllShouldReturnAllAuthors() { var optionsBuilder = new DbContextOptionsBuilder <BookTubeContext>() .UseInMemoryDatabase(Guid.NewGuid().ToString()); var dbContext = new BookTubeContext(optionsBuilder.Options); var service = new AuthorsService(dbContext); var authors = new List <Author> { new Author { Id = 1, Name = "Ivan Vazov", Bio = "Born in Sopot, Bulgaria" }, new Author { Id = 2, Name = "Aleko Konstantinov", Bio = "Born in Svishtov, Bulgaria" }, new Author { Id = 3, Name = "Elin Pelin", Bio = "Born in Bailovo, Bulgaria" } }; foreach (var author in authors) { await dbContext.Authors.AddAsync(author); } await dbContext.SaveChangesAsync(); var sortedPublishers = authors.OrderBy(x => x.Name).ToList(); var actual = service.All(); Assert.Equal(sortedPublishers, actual); }