chore: add type hint for reconstructor (#12527)

* chore: add type hint for reconstructor

* chore: fix attr-defined

* chore: use defined typevar

* chore: ignore type error

(cherry picked from commit 299284cec65076fd4c76bf1efaae60b60f4d4f7b)

diff --git a/lib/sqlalchemy/orm/mapper.py b/lib/sqlalchemy/orm/mapper.py
index eab2be558f69b87ae93dff94a87e0f7a5d86e17f..5844854f9d03188c4d043efae5b95ec4583aa86b 100644 (file)
--- a/lib/sqlalchemy/orm/mapper.py
+++ b/lib/sqlalchemy/orm/mapper.py
@@ -4304,7 +4304,7 @@ def _dispose_registries(registries: Set[_RegistryType], cascade: bool) -> None:
         reg._new_mappers = False
 
 
-def reconstructor(fn):
+def reconstructor(fn: _Fn) -> _Fn:
     """Decorate a method as the 'reconstructor' hook.
 
     Designates a single method as the "reconstructor", an ``__init__``-like
@@ -4330,7 +4330,7 @@ def reconstructor(fn):
         :meth:`.InstanceEvents.load`
 
     """
-    fn.__sa_reconstructor__ = True
+    fn.__sa_reconstructor__ = True  # type: ignore[attr-defined]
     return fn