Add support for django-configurations

README.md

@@ -74,3 +74,18 @@ Otherwise, custom type will be created in mypy, named `MyUser__MyUserManager`, w
 We have Gitter here: <https://gitter.im/mypy-django/Lobby>
 
 If you think you have more generic typing issue, please refer to https://github.com/python/mypy and their Gitter.
+
+
+### Django-configurations support
+
+When using <https://django-configurations.readthedocs.io> you will need to set `django_configuration` in the `[mypy.plugins.django-stubs]` section.
+
+```ini
+[mypy]
+strict_optional = True
+
+; this one is new
+[mypy.plugins.django-stubs]
+django_settings_module = mysettings
+django_configuration = ProductionConfiguration
+```

mypy_django_plugin/django/context.py

@@ -41,10 +41,13 @@ def temp_environ():
         os.environ.update(environ)
 
 
-def initialize_django(settings_module: str) -> Tuple['Apps', 'LazySettings']:
+def initialize_django(settings_module: str, configuration: Optional[str] = None) -> Tuple['Apps', 'LazySettings']:
     with temp_environ():
         os.environ['DJANGO_SETTINGS_MODULE'] = settings_module
 
+        if configuration is not None:
+            os.environ['DJANGO_CONFIGURATION'] = configuration
+
         def noop_class_getitem(cls, key):
             return cls
 
@@ -60,7 +63,13 @@ def noop_class_getitem(cls, key):
         apps.get_swappable_settings_name.cache_clear()  # type: ignore
 
         if not settings.configured:
-            settings._setup()
+            # we are not using django configuration
+            if configuration is None:
+                settings._setup()
+            else:
+                from configurations import importer  # type: ignore
+                importer.install(check_options=True)
+                settings._setup()
 
         apps.populate(settings.INSTALLED_APPS)
 
@@ -182,13 +191,14 @@ def resolve_lookup(self, model_cls: Type[Model], lookup: str) -> Field:
 
 
 class DjangoContext:
-    def __init__(self, django_settings_module: str) -> None:
+    def __init__(self, django_settings_module: str, django_configuration: Optional[str] = None) -> None:
         self.fields_context = DjangoFieldsContext(self)
         self.lookups_context = DjangoLookupsContext(self)
 
         self.django_settings_module = django_settings_module
+        self.django_configuration = django_configuration
 
-        apps, settings = initialize_django(self.django_settings_module)
+        apps, settings = initialize_django(self.django_settings_module, self.django_configuration)
         self.apps_registry = apps
         self.settings = settings
 

mypy_django_plugin/main.py

@@ -69,11 +69,35 @@ def extract_django_settings_module(config_file_path: Optional[str]) -> str:
     return django_settings_module
 
 
+def extract_django_configuration(config_file_path: Optional[str]) -> Optional[str]:
+    errors = Errors()
+    if config_file_path is None:
+        errors.report(0, None,
+                      "'django_settings_module' is not set: no mypy config file specified")
+        errors.raise_error()
+
+    parser = configparser.ConfigParser()
+    parser.read(config_file_path)  # type: ignore
+
+    if not parser.has_section('mypy.plugins.django-stubs'):
+        errors.report(0, None,
+                      "'django_configuration' is not set: no section [mypy.plugins.django-stubs]",
+                      file=config_file_path)
+        errors.raise_error()
+    if not parser.has_option('mypy.plugins.django-stubs', 'django_configuration'):
+        return None
+
+    django_configuration = parser.get('mypy.plugins.django-stubs',
+                                      'django_configuration').strip('\'"')
+    return django_configuration
+
+
 class NewSemanalDjangoPlugin(Plugin):
     def __init__(self, options: Options) -> None:
         super().__init__(options)
         django_settings_module = extract_django_settings_module(options.config_file)
-        self.django_context = DjangoContext(django_settings_module)
+        django_configuration = extract_django_configuration(options.config_file)
+        self.django_context = DjangoContext(django_settings_module, django_configuration)
 
     def _get_current_queryset_bases(self) -> Dict[str, int]:
         model_sym = self.lookup_fully_qualified(fullnames.QUERYSET_CLASS_FULLNAME)