public async Task DeletePlayListShouldDeletePlayList()
{
var playList = new PlayList {
Id = 1
};
_mixBLMock.Setup(x => x.DeletePlayListAsync(It.IsAny <PlayList>())).Returns(Task.FromResult <PlayList>(playList));
var playlistController = new PlayListController(_mixBLMock.Object);
var result = await playlistController.DeletePlayListAsync(playList.Id);
Assert.IsAssignableFrom <NoContentResult>(result);
_mixBLMock.Verify(x => x.DeletePlayListAsync((It.IsAny <PlayList>())));
}