Best way to structure async integration tests

Hey everyone! I'm writing a library that represents a node in a network (cryptographic) protocol. I want to write an integration test simulating having several nodes talking to each other and make sure it goes to completion as expected. Faking out the network interface is easy, but I'm not sure how best to structure the actual integration test. In particular I want to check that the state machine works the way it's intended and reports the right states to clients. For example: pub enum StateKin...