Made it possible to change an application's label in its configuration.

Fixed #21683.

1 files changed, 21 insertions, 0 deletions

diff --git a/django/apps/registry.py b/django/apps/registry.py
index 317bde33fe..7ff1c6625d 100644
--- a/django/apps/registry.py
+++ b/django/apps/registry.py
@@ -201,6 +201,27 @@ class Apps(object):
         app_config = self.app_configs.get(app_name.rpartition(".")[2])
         return app_config is not None and app_config.name == app_name
 
+    def get_containing_app_config(self, object_name):
+        """
+        Look for an app config containing a given object.
+
+        object_name is the dotted Python path to the object.
+
+        Returns the app config for the inner application in case of nesting.
+        Returns None if the object isn't in any registered app config.
+
+        It's safe to call this method at import time, even while the registry
+        is being populated.
+        """
+        candidates = []
+        for app_config in self.app_configs.values():
+            if object_name.startswith(app_config.name):
+                subpath = object_name[len(app_config.name):]
+                if subpath == '' or subpath[0] == '.':
+                    candidates.append(app_config)
+        if candidates:
+            return sorted(candidates, key=lambda ac: -len(ac.name))[0]
+
     def get_registered_model(self, app_label, model_name):
         """
         Similar to get_model(), but doesn't require that an app exists with