AsyncUnit is an extension to RackUnit with forms for testing communication over asynchronous channels.
(check-unicast chan v #:description description #:timeout timeout)
Checks that chan produces the message v within timeout seconds, using description as a description of the expected message.
(check-unicast-match chan pat pred #:timeout timeout)
Checks that chan produces a message that matches the pattern pat within timeout seconds. pred acts like it does for check-match.(pred and timeout are optional, but I need to figure out how to show that in Scribble.)