Bug: Incompatible signatures when using WebsocketListener class

[olzhasar]

Description

mypy complains about incompatible signatures when trying to use the WebsocketListener class. The issue can be reproduced by running mypy over the documentation example.

mypy produces the following error:

docs/examples/websockets/listener_class_based_async.py:8: error: Signature of "on_accept" incompatible with supertype "WebsocketListener"  [override]
docs/examples/websockets/listener_class_based_async.py:8: note:      Superclass:
docs/examples/websockets/listener_class_based_async.py:8: note:          Optional[Callable[..., Any]]
docs/examples/websockets/listener_class_based_async.py:8: note:      Subclass:
docs/examples/websockets/listener_class_based_async.py:8: note:          def on_accept(self, socket: WebSocket[Any, Any, Any]) -> Coroutine[Any, Any, None]
docs/examples/websockets/listener_class_based_async.py:11: error: Signature of "on_disconnect" incompatible with supertype "WebsocketListener"  [override]
docs/examples/websockets/listener_class_based_async.py:11: note:      Superclass:
docs/examples/websockets/listener_class_based_async.py:11: note:          Optional[Callable[..., Any]]
docs/examples/websockets/listener_class_based_async.py:11: note:      Subclass:
docs/examples/websockets/listener_class_based_async.py:11: note:          def on_disconnect(self, socket: WebSocket[Any, Any, Any]) -> Coroutine[Any, Any, None]

I'm convinced that docs/examples should be typed checked, it seems that they are currently not.

URL to code causing the issue

No response

MCVE

from litestar import Litestar, WebSocket
from litestar.handlers import WebsocketListener


class Handler(WebsocketListener):
    path = "/"

    async def on_accept(self, socket: WebSocket) -> None:
        print("Connection accepted")

    async def on_disconnect(self, socket: WebSocket) -> None:
        print("Connection closed")

    async def on_receive(self, data: str) -> str:
        return data


app = Litestar([Handler])

Steps to reproduce

1. Run `mypy docs/examples/websockets/listener_class_based_async.py`

Logs

No response

Litestar Version

2.12.1

Platform

• [X] Linux
• [X] Mac
• [ ] Windows
• [ ] Other (Please specify in the description above)

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