WIP: provide typing default for optional typevar

Author: CoderJoshDK

disnake/ui/button.py

@@ -3,7 +3,17 @@
 from __future__ import annotations
 
 import os
-from typing import TYPE_CHECKING, Any, Callable, ClassVar, Optional, Tuple, TypeVar, Union, overload
+from typing import (
+    TYPE_CHECKING,
+    Any,
+    Callable,
+    ClassVar,
+    Optional,
+    Tuple,
+    TypeVar,
+    Union,
+    overload,
+)
 
 from ..components import Button as ButtonComponent
 from ..enums import ButtonStyle, ComponentType
@@ -17,18 +27,23 @@
 )
 
 if TYPE_CHECKING:
-    from typing_extensions import ParamSpec, Self
+    from typing_extensions import (
+        ParamSpec,
+        Self,
+        TypeVar,  # noqa: TC004
+    )
 
     from ..emoji import Emoji
     from .item import ItemCallbackType
     from .view import View
 
+    V_co = TypeVar("V_co", bound="Optional[View]", covariant=True, default=None)
 else:
     ParamSpec = TypeVar
+    V_co = TypeVar("V_co", bound="Optional[View]", covariant=True)
 
 B = TypeVar("B", bound="Button")
 B_co = TypeVar("B_co", bound="Button", covariant=True)
-V_co = TypeVar("V_co", bound="Optional[View]", covariant=True)
 P = ParamSpec("P")
 
 

disnake/ui/item.py

@@ -25,11 +25,12 @@
     "Item",
 )
 
-I = TypeVar("I", bound="Item[Any]")  # noqa: E741
-V_co = TypeVar("V_co", bound="Optional[View]", covariant=True)
 
 if TYPE_CHECKING:
-    from typing_extensions import Self
+    from typing_extensions import (
+        Self,
+        TypeVar,  # noqa: TC004
+    )
 
     from ..client import Client
     from ..components import ActionRowChildComponent, Component
@@ -38,8 +39,18 @@
     from ..types.components import ActionRowChildComponent as ActionRowChildComponentPayload
     from .view import View
 
+    V_co = TypeVar("V_co", bound="Optional[View]", covariant=True, default=None)
+    I = TypeVar("I", bound="Item[Any]", default="Item[None]")  # noqa: E741
     ItemCallbackType = Callable[[V_co, I, MessageInteraction], Coroutine[Any, Any, Any]]
 
+    SelfViewT = TypeVar("SelfViewT", bound="Optional[View]", default=None)
+else:
+    I = TypeVar("I", bound="Item[Any]")  # noqa: E741
+    V_co = TypeVar("V_co", bound="Optional[View]", covariant=True)
+
+    SelfViewT = TypeVar("SelfViewT", bound="Optional[View]")
+
+
 ClientT = TypeVar("ClientT", bound="Client")
 UIComponentT = TypeVar("UIComponentT", bound="UIComponent")
 
@@ -220,9 +231,6 @@ async def callback(self, interaction: MessageInteraction[ClientT], /) -> None:
         pass
 
 
-SelfViewT = TypeVar("SelfViewT", bound="Optional[View]")
-
-
 # While the decorators don't actually return a descriptor that matches this protocol,
 # this protocol ensures that type checkers don't complain about statements like `self.button.disabled = True`,
 # which work as `View.__init__` replaces the handler with the item.

disnake/ui/select/base.py

@@ -28,19 +28,24 @@
 __all__ = ("BaseSelect",)
 
 if TYPE_CHECKING:
-    from typing_extensions import ParamSpec, Self
+    from typing_extensions import (
+        ParamSpec,
+        Self,
+        TypeVar,  # noqa: TC004
+    )
 
     from ...abc import Snowflake
     from ...interactions import MessageInteraction
     from ..item import ItemCallbackType
     from ..view import View
 
+    V_co = TypeVar("V_co", bound="Optional[View]", covariant=True, default=None)
 else:
     ParamSpec = TypeVar
+    V_co = TypeVar("V_co", bound="Optional[View]", covariant=True)
 
 
 S_co = TypeVar("S_co", bound="BaseSelect", covariant=True)
-V_co = TypeVar("V_co", bound="Optional[View]", covariant=True)
 SelectMenuT = TypeVar("SelectMenuT", bound=AnySelectMenu)
 SelectValueT = TypeVar("SelectValueT")
 P = ParamSpec("P")

disnake/ui/view.py

@@ -170,7 +170,7 @@ async def __timeout_task_impl(self) -> None:
             await asyncio.sleep(self.__timeout_expiry - now)
 
     def to_components(self) -> List[ActionRowPayload]:
-        def key(item: Item[View]) -> int:
+        def key(item: Item[Self]) -> int:
             return item._rendered_row or 0
 
         children = sorted(self.children, key=key)