public void UninitializedAgeShouldBeNull()
{
var year = new Year();
year.Age(DateTime.Now).ShouldBeNull();
}
public void FindAgeFromAYear()
{
var year = new Year(1920);
year.Age(new Year(1980)).ShouldEqual(60);
}
public void FindAge()
{
var year = new Year(1985);
year.Age(new DateTime(1995, 8, 25)).ShouldEqual(10);
}