1 files changed, 27 insertions, 18 deletions
diff --git a/lib/sqlalchemy/orm/util.py b/lib/sqlalchemy/orm/util.py
index c50cc5bac..520c95672 100644
--- a/lib/sqlalchemy/orm/util.py
+++ b/lib/sqlalchemy/orm/util.py
@@ -1927,7 +1927,7 @@ def _getitem(iterable_query: Query[Any], item: Any) -> Any:
 
 
 def _is_mapped_annotation(
-    raw_annotation: Union[type, str], cls: Type[Any]
+    raw_annotation: _AnnotationScanType, cls: Type[Any]
 ) -> bool:
     annotated = de_stringify_annotation(cls, raw_annotation)
     return is_origin_of(annotated, "Mapped", module="sqlalchemy.orm")
@@ -1969,9 +1969,14 @@ def _extract_mapped_subtype(
     attr_cls: Type[Any],
     required: bool,
     is_dataclass_field: bool,
-    superclasses: Optional[Tuple[Type[Any], ...]] = None,
+    expect_mapped: bool = True,
 ) -> Optional[Union[type, str]]:
+    """given an annotation, figure out if it's ``Mapped[something]`` and if
+    so, return the ``something`` part.
 
+    Includes error raise scenarios and other options.
+
+    """
     if raw_annotation is None:
 
         if required:
@@ -1989,25 +1994,29 @@ def _extract_mapped_subtype(
     if is_dataclass_field:
         return annotated
     else:
-        # TODO: there don't seem to be tests for the failure
-        # conditions here
-        if not hasattr(annotated, "__origin__") or (
-            not issubclass(
-                annotated.__origin__,  # type: ignore
-                superclasses if superclasses else attr_cls,
-            )
-            and not issubclass(attr_cls, annotated.__origin__)  # type: ignore
+        if not hasattr(annotated, "__origin__") or not is_origin_of(
+            annotated, "Mapped", module="sqlalchemy.orm"
         ):
-            our_annotated_str = (
-                annotated.__name__
+            anno_name = (
+                getattr(annotated, "__name__", None)
                 if not isinstance(annotated, str)
-                else repr(annotated)
-            )
-            raise sa_exc.ArgumentError(
-                f'Type annotation for "{cls.__name__}.{key}" should use the '
-                f'syntax "Mapped[{our_annotated_str}]" or '
-                f'"{attr_cls.__name__}[{our_annotated_str}]".'
+                else None
             )
+            if anno_name is None:
+                our_annotated_str = repr(annotated)
+            else:
+                our_annotated_str = anno_name
+
+            if expect_mapped:
+                raise sa_exc.ArgumentError(
+                    f'Type annotation for "{cls.__name__}.{key}" '
+                    "should use the "
+                    f'syntax "Mapped[{our_annotated_str}]" or '
+                    f'"{attr_cls.__name__}[{our_annotated_str}]".'
+                )
+
+            else:
+                return annotated
 
         if len(annotated.__args__) != 1:  # type: ignore
             raise sa_exc.ArgumentError(