Fix AttributeError on ManyToOneRel fields (#575)

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ### Added
 
 ### Changed
+- Fix AttributeError when processing models with reverse ForeignKey relations (`ManyToOneRel`) ([#575](https://github.com/model-bakers/model_bakery/issues/575))
 - [dev] Replace mypy with ty as the primary type checker with stricter type checks
 
 ### Removed

model_bakery/baker.py

@@ -25,7 +25,11 @@
 from django.db.models.fields.related import (
     ReverseManyToOneDescriptor as ForeignRelatedObjectsDescriptor,
 )
-from django.db.models.fields.reverse_related import ManyToOneRel, OneToOneRel
+from django.db.models.fields.reverse_related import (
+    ForeignObjectRel,
+    ManyToOneRel,
+    OneToOneRel,
+)
 
 from . import generators, random_gen
 from ._types import M, NewM
@@ -612,6 +616,11 @@ def _skip_field(self, field: Field) -> bool:  # noqa: C901
         if isinstance(field, OneToOneField) and self._remote_field(field).parent_link:
             return True
 
+        # Skip reverse relations (ManyToOneRel, OneToOneRel, ManyToManyRel)
+        # These are handled separately in create_by_related_name
+        if isinstance(field, ForeignObjectRel):
+            return True
+
         other_fields_to_skip = [
             AutoField,
             OrderWrt,

tests/test_baker.py

@@ -5,7 +5,7 @@
 
 from django.apps import apps
 from django.conf import settings
-from django.db.models import Manager
+from django.db.models import Manager, ManyToOneRel
 from django.db.models.signals import m2m_changed
 from django.test import TestCase, override_settings
 
@@ -1445,3 +1445,16 @@ def test_auto_field_generators_start_from_one(self):
 
         small_values = [random_gen.gen_small_auto_field() for _ in range(100)]
         assert all(v >= 1 for v in small_values), "SmallAutoField values should be >= 1"
+
+
+class TestReverseRelations:
+    """Regression tests for issue #575."""
+
+    def test_skip_field_skips_reverse_relation_with_fill_optional(self):
+        reverse_rel = next(
+            f for f in models.Person._meta.get_fields() if isinstance(f, ManyToOneRel)
+        )
+
+        baker_instance = baker.Baker(models.Person)
+        baker_instance.fill_in_optional = True
+        assert baker_instance._skip_field(reverse_rel) is True