Smartpy Michelson errors only on deployment (inconsistent_annotations, inconsistent_types)

Question

Getting this error ONLY when deploying the smartpy contract. There are otherwise no errors when testing/compiling the code. Is there a way to get a better error message? Is there a way to trigger these errors without having to deploy the contract? It's hard to understand exactly what is wrong with the data I'm storing.

Error:

failed(permanent: proto.008-PtEdo2Zk.michelson_v1.ill_typed_contract), (permanent: proto.008-PtEdo2Zk.michelson_v1.bad_stack), (permanent: proto.008-PtEdo2Zk.michelson_v1.bad_stack_item), (permanent: proto.008-PtEdo2Zk.michelson_v1.inconsistent_types), (permanent: proto.008-PtEdo2Zk.michelson_v1.inconsistent_annotations)

The culprit for this exception is the storage for TZOrder.purchased_items

class TZOrder:
    """
        Stored confirmed order.
    """
    def get_type():
        return sp.TRecord(
            buyer = sp.TAddress, 
            total_cost=sp.TNat, 
            purchased_items = sp.TList(TZItemOrderData.get_type())
        ).layout(( "buyer", ("total_cost", ("purchased_items"))))

    def make(buyer, total_cost, date, purchased_items):
        return sp.set_type_expr(
            sp.record(buyer = buyer, total_cost = total_cost, purchased_items = purchased_items),
            TZOrder.get_type())


@sp.entry_point
    def buy_item(self, params):
        sp.set_type(params.checkout, TZCheckoutParams.get_type())
        tz_item_orders_data = sp.local('tz_item_orders_data', sp.list())

        sp.for item_to_purchase in params.checkout.items_to_purchase.items():
            sp.set_type(item_to_purchase, sp.TRecord(key = sp.TNat, value = sp.TNat))
            
            # verify item exists
            sp.verify(self.data.shop_items.contains(item_to_purchase.key), message=TZErrorMessage.ITEM_DOESNT_EXIST)

            # verify there is enough inventory
            sp.verify(self.data.shop_items[item_to_purchase.key].amount >= item_to_purchase.value, message=TZErrorMessage.NOT_ENOUGH_INVENTORY)
            
            # deduct amount that was bought
            self.data.shop_items[item_to_purchase.key].amount = sp.as_nat(self.data.shop_items[item_to_purchase.key].amount - item_to_purchase.value)

            # append to list to save under the Order model
            tz_item_orders_data.value.push(TZItemOrderData.make(item_to_purchase.key,item_to_purchase.value))
        # ensure order id isn't already taken
        sp.verify(~self.data.orders.contains(self.data.next_order_id), message=TZErrorMessage.ID_ALREADY_IN_USE)

        self.data.orders[self.data.next_order_id] = TZOrder.make(
            sp.sender,
            # self.data.next_order_id,
            sp.as_nat(0),
            sp.now,
            tz_item_orders_data.value
        )

Full code here

Answer 1

That was fixed in granadanet by this merge request: https://gitlab.com/tezos/tezos/-/merge_requests/2815

You need to add self.add_flag("initial-cast") in the contract constructor to solve the issue until mainnet adopts the new protocol.