add DatabaseError wrapping for aggregate() queries

Author: timgraham

django_mongodb/features.py

@@ -102,9 +102,6 @@ class DatabaseFeatures(BaseDatabaseFeatures):
         # 'Col' object has no attribute 'utcoffset'
         "expressions.tests.IterableLookupInnerExpressionsTests.test_expressions_in_lookups_join_choice",
         "expressions.tests.IterableLookupInnerExpressionsTests.test_in_lookup_allows_F_expressions_and_expressions_for_datetimes",
-        # pymongo.errors.OperationFailure:  $multiply only supports numeric
-        # types, not date. (should be wrapped in DatabaseError).
-        "expressions.tests.FTimeDeltaTests.test_invalid_operator",
         # alias().order_by() doesn't work.
         "annotations.tests.AliasTests.test_order_by_alias",
         # annotate() + values_list() + order_by() loses annotated value.

django_mongodb/query.py

@@ -91,6 +91,7 @@ def delete(self):
         options = self.connection.operation_flags.get("delete", {})
         return self.collection.delete_many(self.mongo_query, **options).deleted_count
 
+    @wrap_database_errors
     def get_cursor(self):
         if self.query.low_mark == self.query.high_mark:
             return []