Hi Jason, I heartily support unit testing practices and introducing a mocking framework into ignite development environment. Today I can hardly find a single unit test in Apache Ignite, which does not allow me to use the best TDD and CI/CD practices like running tests on every commit (or even on every "save file"!).
I recently started developing an isolated component based on Apache Ignite and, since I use TDD and write lots of unit tests, I had to add a mocking framework to my project. I started from Mockito (version 1.something) and found I could not do some things with Mockito due to Ignite currently not designed for unit testing. I believe I could not find a way to mock some private initialisation block with Mockito. Thus, I switched to JMockit - it allowed me to mock what I wanted and it seems you can mock virtually everything with JMockit. I know that a situation when you have to mock something private or static indicates not very modular and extendable design but you do not have much of a choice with Ignite since you already have huge amount of code and it would be really hard to refactor everything to make it testable since Ignite development process is heavy and your project could be stuck waiting for Ignite changes. Did you consider JMockit over Mockito? It seems JMockit supports both record-replay-verity and setup-run-verify models as well as BDD semantics API.
