public void PlayTestWithShadows()
{
var helper = new PlayTestHelper();
// queue with one item, add shadow
helper.Enqueue(QueueItems[0]);
helper.Manager.NextSongShadow = QueueItems[1];
helper.Play(QueueItems[0], 0);
// first song is playing, check that the shadow is preparing
helper.CheckIsPreparing(QueueItems[1]);
helper.Enqueue(QueueItems[2]);
// a new song is enqueued, check that it is preparing
helper.CheckIsPreparing(QueueItems[2]);
helper.CheckTasksCanceled(1);
// next song index is valid
helper.CheckNextSongIndex(1);
helper.InvokeSongEnd();
helper.Play(QueueItems[2], 1);
// shadow is kept
helper.CheckIsPreparing(QueueItems[1]);
// next song index is still valid
helper.CheckNextSongIndex(2);
helper.InvokeSongEnd();
helper.AssertAtEndOfQueue();
// Add the shadow song when not playing and at end of queue
helper.Enqueue(QueueItems[1]);
helper.Play(QueueItems[1], 2);
// shadow gets cleared after play
Assert.AreSame(helper.Manager.NextSongShadow, null);
helper.CheckIsPreparing(null);
helper.CheckNextSongIndex(3);
helper.InvokeSongEnd();
helper.AssertAtEndOfPlay();
helper.CheckTasksCanceled(1);
}