public void Expired()
{
ResourceCollection<CreditCard> collection = gateway.CreditCard.Expired();
Assert.IsTrue(collection.MaximumCount > 1);
List<string> cards = new List<string>();
foreach (CreditCard card in collection) {
Assert.IsTrue(card.IsExpired.Value);
cards.Add(card.Token);
}
HashSet<string> uniqueCards = new HashSet<string>(cards);
Assert.AreEqual(uniqueCards.Count, collection.MaximumCount);
}