Make Qtconsole work with PyZMQ 25 (#914)

Co-authored-by: Steven Silvester <steven.silvester@ieee.org>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

jupyter_client/threaded.py

@@ -71,7 +71,7 @@ def __init__(
         def setup_stream():
             assert self.socket is not None
             self.stream = zmqstream.ZMQStream(self.socket, self.ioloop)
-            self.stream.on_recv(self._handle_recv)  # type:ignore[arg-type]
+            self.stream.on_recv(self._handle_recv)
             evt.set()
 
         assert self.ioloop is not None
@@ -115,21 +115,24 @@ def thread_send():
         assert self.ioloop is not None
         self.ioloop.add_callback(thread_send)
 
-    def _handle_recv(self, future_msg: Awaitable) -> None:
+    def _handle_recv(self, msg: Union[List[bytes], Awaitable]) -> None:
         """Callback for stream.on_recv.
 
         Unpacks message, and calls handlers with it.
         """
-        assert self.ioloop is not None
-        loop = self.ioloop._asyncio_event_loop  # type:ignore[attr-defined]
-        msg_list = loop.run_until_complete(get_msg(future_msg))
+        if asyncio.isfuture(msg):
+            assert self.ioloop is not None
+            loop = self.ioloop._asyncio_event_loop  # type:ignore[attr-defined]
+            msg_list = loop.run_until_complete(get_msg(msg))
+        else:
+            msg_list = msg
         assert self.session is not None
         ident, smsg = self.session.feed_identities(msg_list)
-        msg = self.session.deserialize(smsg)
+        new_msg = self.session.deserialize(smsg)
         # let client inspect messages
         if self._inspect:
-            self._inspect(msg)
-        self.call_handlers(msg)
+            self._inspect(new_msg)
+        self.call_handlers(new_msg)
 
     def call_handlers(self, msg: Dict[str, Any]) -> None:
         """This method is called in the ioloop thread when a message arrives.