implement ObjectIdAutoField.get_internal_type()

It also requires implementing DatabaseOperations.integer_field_range() since
the base class's implementation doesn't handle "ObjectIdAutoField" and
ObjectIdAutoField accepts integers.

Author: timgraham

django_mongodb/fields/auto.py

@@ -39,6 +39,9 @@ def get_prep_value(self, value):
                 return int(value)
             raise ValueError(f"Field '{self.name}' expected an ObjectId but got {value!r}.") from e
 
+    def get_internal_type(self):
+        return "ObjectIdAutoField"
+
     def db_type(self, connection):
         return "objectId"
 

django_mongodb/operations.py

@@ -214,6 +214,17 @@ def explain_query_prefix(self, format=None, **options):
         super().explain_query_prefix(format, **options)
         return validated_options
 
+    def integer_field_range(self, internal_type):
+        # MongODB doesn't enforce any integer constraints, but it supports
+        # integers up to 64 bits.
+        if internal_type in {
+            "PositiveBigIntegerField",
+            "PositiveIntegerField",
+            "PositiveSmallIntegerField",
+        }:
+            return (0, 9223372036854775807)
+        return (-9223372036854775808, 9223372036854775807)
+
     def prepare_join_on_clause(self, lhs_table, lhs_field, rhs_table, rhs_field):
         lhs_expr, rhs_expr = super().prepare_join_on_clause(
             lhs_table, lhs_field, rhs_table, rhs_field

tests/model_fields_/test_autofield.py

@@ -11,6 +11,10 @@ def test_deconstruct(self):
         self.assertEqual(args, [])
         self.assertEqual(kwargs, {"primary_key": True})
 
+    def test_get_internal_type(self):
+        f = ObjectIdAutoField()
+        self.assertEqual(f.get_internal_type(), "ObjectIdAutoField")
+
     def test_to_python(self):
         f = ObjectIdAutoField()
         self.assertEqual(f.to_python("1"), 1)