The read and write functions will be called by a higher up layer, so I
need to open the file manually in the test.
Signed-off-by: Anna Schumaker <schumaker.anna@gmail.com>
I make sure to remove empty playlists from the deck and throw an error
if there are no playable tracks on the deck.
Signed-off-by: Anna Schumaker <schumaker.anna@gmail.com>
