From 421cc4e4499a582a3ad38f99b1a455ff54539431 Mon Sep 17 00:00:00 2001
From: tamenol <37591107+tamenol@users.noreply.github.com>
Date: Tue, 21 Jun 2022 11:39:18 +0200
Subject: [PATCH 1/3] fix typing in add_listener and remove_listener

Use the union to typecheck these functions
---
 can/notifier.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/can/notifier.py b/can/notifier.py
index f7c004c4e..cbf7cde5d 100644
--- a/can/notifier.py
+++ b/can/notifier.py
@@ -166,7 +166,7 @@ def _on_error(self, exc: Exception) -> bool:
 
         return was_handled
 
-    def add_listener(self, listener: Listener) -> None:
+    def add_listener(self, listener: MessageRecipient) -> None:
         """Add new Listener to the notification list.
         If it is already present, it will be called two times
         each time a message arrives.
@@ -175,7 +175,7 @@ def add_listener(self, listener: Listener) -> None:
         """
         self.listeners.append(listener)
 
-    def remove_listener(self, listener: Listener) -> None:
+    def remove_listener(self, listener: MessageRecipient) -> None:
         """Remove a listener from the notification list. This method
         throws an exception if the given listener is not part of the
         stored listeners.

From 6980507e927a29b8f61e2b0028ec398384b92aaa Mon Sep 17 00:00:00 2001
From: tamenol <37591107+tamenol@users.noreply.github.com>
Date: Tue, 21 Jun 2022 12:35:55 +0200
Subject: [PATCH 2/3] add awaitable to MessageRecipient definition; remove
 unneeded cast

---
 can/notifier.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/can/notifier.py b/can/notifier.py
index cbf7cde5d..4df969115 100644
--- a/can/notifier.py
+++ b/can/notifier.py
@@ -14,7 +14,7 @@
 
 logger = logging.getLogger("can.Notifier")
 
-MessageRecipient = Union[Listener, Callable[[Message], None]]
+MessageRecipient = Union[Listener, Callable[[Message], Union[Awaitable[None], None]]]
 
 
 class Notifier:
@@ -140,7 +140,7 @@ def _on_message_available(self, bus: BusABC) -> None:
 
     def _on_message_received(self, msg: Message) -> None:
         for callback in self.listeners:
-            res = cast(Union[None, Optional[Awaitable[Any]]], callback(msg))
+            res = callback(msg)
             if res is not None and self._loop is not None and asyncio.iscoroutine(res):
                 # Schedule coroutine
                 self._loop.create_task(res)

From d431a3a30795ad16a63e147d659ceadde9d9661b Mon Sep 17 00:00:00 2001
From: tamenol <37591107+tamenol@users.noreply.github.com>
Date: Wed, 22 Jun 2022 11:04:00 +0200
Subject: [PATCH 3/3] remove unused imports

---
 can/notifier.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/can/notifier.py b/can/notifier.py
index 4df969115..2adae431e 100644
--- a/can/notifier.py
+++ b/can/notifier.py
@@ -6,7 +6,7 @@
 import logging
 import threading
 import time
-from typing import Any, Callable, cast, Iterable, List, Optional, Union, Awaitable
+from typing import Callable, Iterable, List, Optional, Union, Awaitable
 
 from can.bus import BusABC
 from can.listener import Listener