public void CallCreateServiceMethodCreateArtistOnce_WhenInvoked()
        {
            // Arrange
            var createService = new Mock <ICreationService>();
            var artistService = new Mock <IArtistService>();
            var albumService  = new Mock <IAlbumService>();
            var genreService  = new Mock <IGenreService>();

            createService.Setup(x => x.CreateArtist(It.IsAny <string>()));

            var sut = new CreateController(
                createService.Object,
                artistService.Object,
                albumService.Object,
                genreService.Object);

            var model = new CreateArtistViewModel()
            {
                Name = "Artist Name"
            };

            // Act
            sut.CreateArtist(model);

            // Assert
            createService.Verify(x => x.CreateArtist(It.IsAny <string>()), Times.Once);
        }