Write differential testing driver using ibc-go framework

[danwt]

Idea

A driver will be needed for differential testing. For the first application, the driver should have the actions outlined by Marius and should orchestrate the system in memory using ibc-go/testing.

In particular the actions are

• on provider
  • delegate(D, V, A), where D is a delegator, V is a validator and A is an amount
  • undelegate(D, V, A)
  • redelegate(D, Vsrc, Vdst, A)
  • slash(V, infractionHeight, slashFactor)
  • jumpToBlock(h), where h is a height larger than the current height
• on consumer
  • slash(V, infractionHeight, slashFactor)
  • jumpToBlock(h)

Tasks

• Locate the code locations where these abstract actions can be called
• Write a driver using ibc-go/testing to call these actions
• Write some input traces by hand to check if the driver is sensible

Resources

• Parent issue: Apply differential testing based on a reference implementation #60
• Sibling issue: Write reference implementation to generate traces for differential testing #88

[danwt]

Closed as PR

• In-memory differential testing for established chains #126

tackles this but now it is blocked by the TDD dev cycle. That is: the tests in the PR fail due to a the SUT not being fully implemented. I'm not sure if it makes sense to merge the PR currently, so I'll create another issue for further work.