public void CalculateOrders_EnumerableNull_ThrowsNullArgumentException()
{
var service = new CardService();
void action() => service.CalculateOrders(null);
Assert.Throws <ArgumentNullException>(action);
}
public void CalculateOrders_EnumerableInstance_CallsChangeOrderFromSequence()
{
var service = new CardService();
var card1 = Card.Create("card1-title");
var card2 = Card.Create("card2-title");
var cards = new List <Card> {
card1, card2
};
service.CalculateOrders(cards);
Assert.Equal(0, card1.Order);
Assert.Equal(1, card2.Order);
}