Fallback to inspect.getmodule for models not exported in the app's …

…models module (#66)

src/django_autotyping/stubbing/django_context/django_context.py

@@ -1,6 +1,8 @@
 from __future__ import annotations
 
+import inspect
 from collections import defaultdict
+from types import ModuleType
 
 from django.apps.registry import Apps
 from django.conf import LazySettings
@@ -25,12 +27,26 @@ def __init__(self, apps: Apps, settings: LazySettings) -> None:
 
     @staticmethod
     def _get_model_alias(model: ModelType) -> str:
-        """Return an alias of the model, by converting the app label to PascalCase and joining
+        """Return an alias of the model.
+
+        The alias is constructed by converting the app label to PascalCase and joining
         the app label to the model name.
         """
         app_label = to_pascal(model._meta.app_label)
         return f"{app_label}{model.__name__}"
 
+    @staticmethod
+    def _get_model_module(model: ModelType) -> ModuleType:
+        """Return the module object where the model class is exported or defined.
+
+        Use the models module of the app where the model is defined, and fallback
+        to the actual module of the model class in case the model is not exported
+        or present in the models module.
+        """
+        if model._meta.app_config.models_module is not None:
+            return model._meta.app_config.models_module
+        return inspect.getmodule(model)  # type: ignore
+
     @property
     def models(self) -> list[ModelType]:
         """All the defined models. Abstract models are not included."""
@@ -45,7 +61,7 @@ def model_imports(self) -> list[ImportItem]:
 
         return [
             ImportItem(
-                module_name=model._meta.app_config.models_module.__name__,
+                module_name=self._get_model_module(model).__name__,
                 obj_name=model.__name__,
                 alias=self._get_model_alias(model) if self.is_duplicate(model) else None,
             )

tests/stubstestproj/appwithoutmodelsmodule/apps.py

@@ -0,0 +1,10 @@
+from django.apps import AppConfig
+
+
+class AppwithoutmodelsmoduleConfig(AppConfig):
+    default_auto_field = "django.db.models.BigAutoField"
+    name = "stubstestproj.appwithoutmodelsmodule"
+
+    def ready(self) -> None:
+        # See https://github.com/Viicos/django-autotyping/issues/59 for more context:
+        from .extra_models import ExtraModel

tests/stubstestproj/appwithoutmodelsmodule/extra_models/__init__.py

@@ -0,0 +1,11 @@
+from django.db import models
+
+
+class ExtraModel(models.Model):
+    # `ModelBase.__new__` registers every model to the default `Apps` class,
+    # even if the model is not defined/exported in the `AppConfig`'s models module.
+    # This can lead to cases where `AppConfig.models_module` is `None` because
+    # no models module exists, however models are still registered under this
+    # specific `AppConfig`.
+    # See https://github.com/Viicos/django-autotyping/issues/59 as an example.
+    pass

tests/stubstestproj/settings.py

@@ -32,6 +32,7 @@
     "stubstestproj.accounts",
     "stubstestproj.firstapp",
     "stubstestproj.secondapp",
+    "stubstestproj.appwithoutmodelsmodule",
 ]
 
 MIDDLEWARE = [