Workflow unit tests

I would like to define a series of unit tests for my workflows, is this possible or planned?
For a given input, I expect a given output.

If you want to test a whole workflow end-to-end, you could just create another workflow to test it (using a "Retool Workflow" resource query) with some test code around it.

If you want to test some aspects of the workflow internals (e.g. code in specific blocks), I'm currently taking the approach of keeping the code in a git repo with some tests and then copying it across to the necessary blocks. I dare say the new source control features available in the enterprise version may also facilitate something along these lines, without the need to copy the code.