Fixed typing of limit, offset and fetch to allow ``None``.

Fixes: #9183
Change-Id: I1ac3e3698034826122ea8a0cdc9f8f55a10ed6c1

3 files changed, 13 insertions, 12 deletions

diff --git a/lib/sqlalchemy/sql/_typing.py b/lib/sqlalchemy/sql/_typing.py
index 5c1a501e4..e1190f7dd 100644
--- a/lib/sqlalchemy/sql/_typing.py
+++ b/lib/sqlalchemy/sql/_typing.py
@@ -260,6 +260,8 @@ _TypeEngineArgument = Union[Type["TypeEngine[_T]"], "TypeEngine[_T]"]
 
 _EquivalentColumnMap = Dict["ColumnElement[Any]", Set["ColumnElement[Any]"]]
 
+_LimitOffsetType = Union[int, _ColumnExpressionArgument[int], None]
+
 if TYPE_CHECKING:
 
     def is_sql_compiler(c: Compiled) -> TypeGuard[SQLCompiler]:
diff --git a/lib/sqlalchemy/sql/selectable.py b/lib/sqlalchemy/sql/selectable.py
index f43e6b43f..47cf68357 100644
--- a/lib/sqlalchemy/sql/selectable.py
+++ b/lib/sqlalchemy/sql/selectable.py
@@ -109,6 +109,7 @@ if TYPE_CHECKING:
     from ._typing import _ColumnExpressionOrStrLabelArgument
     from ._typing import _FromClauseArgument
     from ._typing import _JoinTargetArgument
+    from ._typing import _LimitOffsetType
     from ._typing import _MAYBE_ENTITY
     from ._typing import _NOT_ENTITY
     from ._typing import _OnClauseArgument
@@ -3955,7 +3956,7 @@ class GenerativeSelect(SelectBase, Generative):
 
     def _offset_or_limit_clause(
         self,
-        element: Union[int, _ColumnExpressionArgument[Any]],
+        element: _LimitOffsetType,
         name: Optional[str] = None,
         type_: Optional[_TypeEngineArgument[int]] = None,
     ) -> ColumnElement[Any]:
@@ -4041,8 +4042,7 @@ class GenerativeSelect(SelectBase, Generative):
 
     @_generative
     def limit(
-        self: SelfGenerativeSelect,
-        limit: Union[int, _ColumnExpressionArgument[int]],
+        self: SelfGenerativeSelect, limit: _LimitOffsetType
     ) -> SelfGenerativeSelect:
         """Return a new selectable with the given LIMIT criterion
         applied.
@@ -4078,7 +4078,7 @@ class GenerativeSelect(SelectBase, Generative):
     @_generative
     def fetch(
         self: SelfGenerativeSelect,
-        count: Union[int, _ColumnExpressionArgument[int]],
+        count: _LimitOffsetType,
         with_ties: bool = False,
         percent: bool = False,
     ) -> SelfGenerativeSelect:
@@ -4133,8 +4133,7 @@ class GenerativeSelect(SelectBase, Generative):
 
     @_generative
     def offset(
-        self: SelfGenerativeSelect,
-        offset: Union[int, _ColumnExpressionArgument[int]],
+        self: SelfGenerativeSelect, offset: _LimitOffsetType
     ) -> SelfGenerativeSelect:
         """Return a new selectable with the given OFFSET criterion
         applied.
diff --git a/lib/sqlalchemy/sql/util.py b/lib/sqlalchemy/sql/util.py
index a92ee9d1a..1dad9ce68 100644
--- a/lib/sqlalchemy/sql/util.py
+++ b/lib/sqlalchemy/sql/util.py
@@ -71,8 +71,8 @@ from ..util.typing import Literal
 from ..util.typing import Protocol
 
 if typing.TYPE_CHECKING:
-    from ._typing import _ColumnExpressionArgument
     from ._typing import _EquivalentColumnMap
+    from ._typing import _LimitOffsetType
     from ._typing import _TypeEngineArgument
     from .elements import BinaryExpression
     from .elements import TextClause
@@ -1411,7 +1411,7 @@ class ColumnAdapter(ClauseAdapter):
 
 
 def _offset_or_limit_clause(
-    element: Union[int, _ColumnExpressionArgument[int]],
+    element: _LimitOffsetType,
     name: Optional[str] = None,
     type_: Optional[_TypeEngineArgument[int]] = None,
 ) -> ColumnElement[int]:
@@ -1427,8 +1427,8 @@ def _offset_or_limit_clause(
 
 
 def _offset_or_limit_clause_asint_if_possible(
-    clause: Optional[Union[int, _ColumnExpressionArgument[int]]]
-) -> Optional[Union[int, _ColumnExpressionArgument[int]]]:
+    clause: _LimitOffsetType,
+) -> _LimitOffsetType:
     """Return the offset or limit clause as a simple integer if possible,
     else return the clause.
 
@@ -1443,8 +1443,8 @@ def _offset_or_limit_clause_asint_if_possible(
 
 
 def _make_slice(
-    limit_clause: Optional[Union[int, _ColumnExpressionArgument[int]]],
-    offset_clause: Optional[Union[int, _ColumnExpressionArgument[int]]],
+    limit_clause: _LimitOffsetType,
+    offset_clause: _LimitOffsetType,
     start: int,
     stop: int,
 ) -> Tuple[Optional[ColumnElement[int]], Optional[ColumnElement[int]]]: