The Java test profiles assume that, particularly default one for InVm transports, the 0-10 protocol will fail, causing renegotiation. If 0-10 InVm support is added then the default protocol will use this. It seems to make more sense to specify exactly the version the client and the broker should announce, and force renegotiation explicitly by disabling various protocol versions on the command line when starting an external Java broker. Note that this is not possible to specify for the InVm profiles anyway. Also, the only protocol that is ever tested will be the highest supported by both broker and client, therefore this is AMQP 0-9-1. In order for the tests not to do surprising things when new protocol versions are added, I think that setting versions explicitly is the best idea. I woulsd also like to add an explicit 0-8 test profile for both InVM and external Java brokers, in order to exercise and get coverage on this code.
In future, I recommend that some form of combinatorial profile system be investigated for the test subsystem, allowing the required protocol, broker type and so on to be specified separately.