Merge "Add support for typing.Literal in Mapped" into main

2 files changed, 14 insertions, 3 deletions

diff --git a/lib/sqlalchemy/orm/decl_api.py b/lib/sqlalchemy/orm/decl_api.py
index c36089fde..e3e2611da 100644
--- a/lib/sqlalchemy/orm/decl_api.py
+++ b/lib/sqlalchemy/orm/decl_api.py
@@ -77,6 +77,7 @@ from ..util import typing as compat_typing
 from ..util.typing import CallableReference
 from ..util.typing import flatten_newtype
 from ..util.typing import is_generic
+from ..util.typing import is_literal
 from ..util.typing import is_newtype
 from ..util.typing import Literal
 
@@ -1218,10 +1219,19 @@ class registry:
     ) -> Optional[sqltypes.TypeEngine[Any]]:
 
         search: Iterable[Tuple[_MatchedOnType, Type[Any]]]
+        python_type_type: Type[Any]
 
         if is_generic(python_type):
-            python_type_type: Type[Any] = python_type.__origin__
-            search = ((python_type, python_type_type),)
+            if is_literal(python_type):
+                python_type_type = cast("Type[Any]", python_type)
+
+                search = (  # type: ignore[assignment]
+                    (python_type, python_type_type),
+                    (Literal, python_type_type),
+                )
+            else:
+                python_type_type = python_type.__origin__
+                search = ((python_type, python_type_type),)
         elif is_newtype(python_type):
             python_type_type = flatten_newtype(python_type)
             search = ((python_type, python_type_type),)
diff --git a/lib/sqlalchemy/orm/decl_base.py b/lib/sqlalchemy/orm/decl_base.py
index 0462a8945..a858f12cb 100644
--- a/lib/sqlalchemy/orm/decl_base.py
+++ b/lib/sqlalchemy/orm/decl_base.py
@@ -66,6 +66,7 @@ from ..util import topological
 from ..util.typing import _AnnotationScanType
 from ..util.typing import de_stringify_annotation
 from ..util.typing import is_fwd_ref
+from ..util.typing import is_literal
 from ..util.typing import Protocol
 from ..util.typing import TypedDict
 from ..util.typing import typing_get_args
@@ -1165,7 +1166,7 @@ class _ClassScanMapperConfig(_MapperConfig):
 
         extracted_mapped_annotation, mapped_container = extracted
 
-        if attr_value is None:
+        if attr_value is None and not is_literal(extracted_mapped_annotation):
             for elem in typing_get_args(extracted_mapped_annotation):
                 if isinstance(elem, str) or is_fwd_ref(
                     elem, check_generic=True