public GroceryItemScanner(IEnumerable <IGroceryItem> items,
                           IGroceryItemOrderFactory orderFactory)
 {
     this.OrderFactory = orderFactory;
     Items             = new List <IGroceryItem>(items);
 }
 public GroceryItemScanner(IGroceryItemOrderFactory orderFactory)
 {
     this.OrderFactory = orderFactory;
     Items             = new List <IGroceryItem>();
 }