<debug_request> publish the <status:idle> while an <execute_request> is running

In ipykernel 5.5.6，both and put msgs into and process the msg with . Although both and publish the ，there are no conflicts.

When it comes to ipykernel 6.5.0, put msgs into and process the msg with , while shell_stream still works in the old way. This means and will publish the in the same time.

I found this problem in jupyterlab when i executed a cell(sleep 600s) in an ipykernel with ，i switched to another ipynb and switched back. The cell was still running, but the kernel execution_state became idle. Then i found the ipykernel received multi and published the status to idle.

As https://jupyter-client.readthedocs.io/en/latest/messaging.html said "Debug requests and replies are sent over the control channel to prevent queuing behind execution requests". It confuses me that why control_requests affect the kernel's execution_state? Should we use another state like control_state?

Start with the Jupyter messaging documentation linked in the issue, then trace control_stream, shell_stream, process_control, and dispatch_shell around control_queue and msg_queue. Reproduce the long-running execute_request with debugger requests and establish how execution_state should behave while control messages are processed.

Scritto dal modello di indicizzazione a partire dal testo della issue.