non-integer quantities now translated to 0 in the cart-update view

collective/shoppingbehavior/shop.py

@@ -193,7 +193,7 @@ def update_cart(self, form):
         new_qtys = form.get('quantities', [])
         for qty_info in new_qtys:
             item_id = qty_info['id']
-            qty = int(qty_info['quantity'])
+            qty = self._as_integer(qty_info['quantity'])
             self.shopper.update_quantity(item_id, qty)
 
     def items(self):
@@ -211,6 +211,15 @@ def items(self):
             contents.append(data)
         return contents
 
+    def _as_integer(self, value):
+        # un-castable values translate to 0
+        try:
+            qty = int(value)
+        except ValueError:
+            qty = 0
+
+        return qty
+
     @property
     def currency(self):
         return u"$"