public void Next_should_be_called_properly()
{
// Arrange
var client = A.Fake <ISpotifyClient>();
A.CallTo(() => client.Player.SkipNext()).Returns(true);
var sut = new NextCommand(client);
// Act
sut.RunCommand();
// Assert
A.CallTo(() => client.Player.SkipNext()).MustHaveHappenedOnceExactly();
}