Do not allow deleting gifts from order.

saleor/graphql/order/mutations/order_line_delete.py

@@ -3,6 +3,7 @@
 from ....core.taxes import zero_taxed_money
 from ....core.tracing import traced_atomic_transaction
 from ....order import events
+from ....order.error_codes import OrderErrorCode
 from ....order.fetch import OrderLineInfo
 from ....order.search import update_order_search_vector
 from ....order.utils import (
@@ -16,6 +17,7 @@
 from ...core.doc_category import DOC_CATEGORY_ORDERS
 from ...core.mutations import BaseMutation
 from ...core.types import OrderError
+from ...core.utils import raise_validation_error
 from ...plugins.dataloaders import get_plugin_manager_promise
 from ..types import Order, OrderLine
 from .utils import EditableOrderValidationMixin, get_webhook_handler_by_order_status
@@ -48,8 +50,7 @@ def perform_mutation(  # type: ignore[override]
             only_type=OrderLine,
         )
         order = line.order
-        cls.check_channel_permissions(info, [order.channel_id])
-        cls.validate_order(line.order)
+        cls.validate(info, order, line)
 
         db_id = line.id
         warehouse_pk = (
@@ -99,3 +100,14 @@ def perform_mutation(  # type: ignore[override]
             func = get_webhook_handler_by_order_status(order.status, manager)
             cls.call_event(func, order)
         return OrderLineDelete(order=order, order_line=line)
+
+    @classmethod
+    def validate(cls, info, order, line):
+        cls.check_channel_permissions(info, [order.channel_id])
+        cls.validate_order(line.order)
+        if line.is_gift:
+            raise_validation_error(
+                message="Order line marked as gift can't be deleted.",
+                field="id",
+                code=OrderErrorCode.NON_REMOVABLE_GIFT_LINE.value,
+            )

saleor/graphql/order/tests/mutations/test_order_line_delete.py

@@ -6,6 +6,7 @@
 
 from .....order import OrderStatus
 from .....order import events as order_events
+from .....order.error_codes import OrderErrorCode
 from .....order.models import OrderEvent
 from .....warehouse.models import Stock
 from ....tests.utils import assert_no_permission, get_graphql_content
@@ -17,6 +18,7 @@
             errors {
                 field
                 message
+                code
             }
             orderLine {
                 id
@@ -232,3 +234,31 @@ def test_draft_order_properly_recalculate_total_after_shipping_product_removed(
     assert data["order"]["total"]["net"]["amount"] == float(
         line.total_price_net_amount
     ) + float(order.shipping_price_net_amount)
+
+
+def test_order_line_delete_non_removable_gift(
+    draft_order,
+    permission_group_manage_orders,
+    staff_api_client,
+):
+    # given
+    query = ORDER_LINE_DELETE_MUTATION
+    permission_group_manage_orders.user_set.add(staff_api_client.user)
+    order = draft_order
+    line = order.lines.first()
+    line.is_gift = True
+    line.save(update_fields=["is_gift"])
+    line_id = graphene.Node.to_global_id("OrderLine", line.id)
+    variables = {"id": line_id}
+
+    # when
+    response = staff_api_client.post_graphql(query, variables)
+    content = get_graphql_content(response)
+
+    # then
+    data = content["data"]["orderLineDelete"]
+    assert not data["orderLine"]
+    errors = data["errors"]
+    assert len(errors) == 1
+    assert errors[0]["field"] == "id"
+    assert errors[0]["code"] == OrderErrorCode.NON_REMOVABLE_GIFT_LINE.name

saleor/graphql/schema.graphql

@@ -12799,6 +12799,7 @@ enum OrderErrorCode @doc(category: "Orders") {
   INVALID_VOUCHER
   INVALID_VOUCHER_CODE
   NON_EDITABLE_GIFT_LINE_QUANTITY
+  NON_REMOVABLE_GIFT_LINE
 }
 
 """An enumeration."""

saleor/order/error_codes.py

@@ -37,6 +37,7 @@ class OrderErrorCode(Enum):
     INVALID_VOUCHER = "invalid_voucher"
     INVALID_VOUCHER_CODE = "invalid_voucher_code"
     NON_EDITABLE_GIFT_LINE_QUANTITY = "non_editable_gift_line_quantity"
+    NON_REMOVABLE_GIFT_LINE = "non_removable_gift_line"
 
 
 class OrderGrantRefundCreateErrorCode(Enum):