lol

venv/Lib/site-packages/sqlalchemy/orm/decl_base.py

@@ -1434,9 +1434,9 @@ class _ClassScanMapperConfig(_MapperConfig):
             cls, "_sa_decl_prepare_nocascade", strict=True
         )
 
+        allow_unmapped_annotations = self.allow_unmapped_annotations
         expect_annotations_wo_mapped = (
-            self.allow_unmapped_annotations
-            or self.is_dataclass_prior_to_mapping
+            allow_unmapped_annotations or self.is_dataclass_prior_to_mapping
         )
 
         look_for_dataclass_things = bool(self.dataclass_setup_arguments)
@@ -1531,7 +1531,15 @@ class _ClassScanMapperConfig(_MapperConfig):
                     # Mapped[] etc. were not used.  If annotation is None,
                     # do declarative_scan so that the property can raise
                     # for required
-                    if mapped_container is not None or annotation is None:
+                    if (
+                        mapped_container is not None
+                        or annotation is None
+                        # issue #10516: need to do declarative_scan even with
+                        # a non-Mapped annotation if we are doing
+                        # __allow_unmapped__, for things like col.name
+                        # assignment
+                        or allow_unmapped_annotations
+                    ):
                         try:
                             value.declarative_scan(
                                 self,
@@ -1609,7 +1617,7 @@ class _ClassScanMapperConfig(_MapperConfig):
                         setattr(cls, k, value)
                         continue
 
-            our_stuff[k] = value  # type: ignore
+            our_stuff[k] = value
 
     def _extract_declared_columns(self) -> None:
         our_stuff = self.properties
@@ -1979,7 +1987,7 @@ class _DeferredMapperConfig(_ClassScanMapperConfig):
 
     # mypy disallows plain property override of variable
     @property  # type: ignore
-    def cls(self) -> Type[Any]:  # type: ignore
+    def cls(self) -> Type[Any]:
         return self._cls()  # type: ignore
 
     @cls.setter
@@ -1999,7 +2007,7 @@ class _DeferredMapperConfig(_ClassScanMapperConfig):
     @classmethod
     def raise_unmapped_for_cls(cls, class_: Type[Any]) -> NoReturn:
         if hasattr(class_, "_sa_raise_deferred_config"):
-            class_._sa_raise_deferred_config()  # type: ignore
+            class_._sa_raise_deferred_config()
 
         raise orm_exc.UnmappedClassError(
             class_,