Fix #298 -- create m2m when using _bulk_create=True

CHANGELOG.md

@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Changed
 - Fixed a bug with `seq` being passed a tz-aware start value [PR #353](https://github.com/model-bakers/model_bakery/pull/353)
+- Create m2m when using `_bulk_create=True` [PR #354](https://github.com/model-bakers/model_bakery/pull/354)
 
 ### Removed
 

model_bakery/baker.py

@@ -787,4 +787,21 @@ def _save_related_objs(model, objects) -> None:
     else:
         manager = baker.model._base_manager
 
-    return manager.bulk_create(entries)
+    created_entries = manager.bulk_create(entries)
+    # set many-to-many relations from kwargs
+    for entry in created_entries:
+        for field in baker.model._meta.many_to_many:
+            if field.name in kwargs:
+                through_model = getattr(entry, field.name).through
+                through_model.objects.bulk_create(
+                    [
+                        through_model(
+                            **{
+                                field.remote_field.name: entry,
+                                field.related_model._meta.model_name: obj,
+                            }
+                        )
+                        for obj in kwargs[field.name]
+                    ]
+                )
+    return created_entries

tests/test_baker.py

@@ -1032,3 +1032,15 @@ def test_annotation_within_manager_get_queryset_are_run_on_make(self):
             _from_manager="objects",
         )
         assert movie.title == movie.name
+
+
+class TestCreateM2MWhenBulkCreate(TestCase):
+    @pytest.mark.django_db
+    def test_create(self):
+        with self.assertNumQueries(22):
+            person = baker.make(models.Person)
+            baker.make(
+                models.Classroom, students=[person], _quantity=20, _bulk_create=True
+            )
+        c1, c2 = models.Classroom.objects.all()[:2]
+        assert list(c1.students.all()) == list(c2.students.all()) == [person]