How to test a socket.io server based on events emitted by the client

I'm trying to set up a server to respond to socket.io clients using nodejs, express and socket.io. I want to write tests to probe the server and make sure it's handling the events correctly and sending appropriate responses to the client.

I tried writing some automated tests using jest but I couldn't figure out how to actually emit events to the server and have it respond.

Unit testing Node.js and WebSockets (Socket.io)

I checked out the above post but it didn't work for me...