public void ShouldCreateToDoItemWithEmptyUser() { var createToDoItemInput = new CreateToDoItemInput { AssignedUserId = null, Description = Faker.Lorem.Sentence() }; using (this.Repository.Record()) { Expect.Call(this.DbContextScopeFactory.Create()); Expect.Call(this.UserRepository.Get(string.Empty)).Constraints(Is.Equal(null)).Repeat.Never(); Expect.Call(this.ToDoItemRepository.Add(null)).Constraints(Is.Anything()).Repeat.Once(); Expect.Call(() => this.Logger.Info(Arg.Text.Contains("Creating ToDoItem for input:"))).Repeat.Once(); Expect.Call(() => this.Logger.Info(Arg.Text.Contains("Created ToDoItem for input:"))).Repeat.Once(); } using (this.Repository.Playback()) { var toDoItemApplicationService = new ToDoItemApplicationService( this.ToDoItemRepository, this.UserRepository, this.DbContextScopeFactory, this.Mapper, this.Logger); toDoItemApplicationService.CreateToDoItem(createToDoItemInput); } }