public void UpdateAuthor_ShouldUpdateValidAuthor() { // Fixture setup var author = new Author() { FirstName = "fhlkhsdgasd", LastName = "klhlkhjsdg", Synopsis = "zlkhzoiutqwp" }; var authorRepo = new InMemoryRepository <Author>(); authorRepo.Add(author); var authorService = new AuthorApplicationService(authorRepo); var expected = new Author() { FirstName = "blah", LastName = "fdlskhgdsa", Synopsis = "fhlkhdfaslkhjgoiuwer" }; // Exercise the SUT (system under test) authorService.UpdateAuthor( author.Id, expected.FirstName, expected.LastName, expected.Synopsis); // State verification var actual = authorRepo.Get(author.Id); Assert.Equal(1, authorRepo.Count()); Assert.Equal(expected.FirstName, actual.FirstName); Assert.Equal(expected.LastName, actual.LastName); Assert.Equal(expected.Synopsis, actual.Synopsis); }