Rather than update readonlyrest.yml (or via the UI) and take the risk of screwing up the permissions, it would be really nice to write “unit tests”. Maybe this would be using a bit the es-plugin to write junit tests.
No, really I want a jar file where I can write real unit tests for rules. Of course I can fire up a es node in docker and run tests against that. A bit slower, but certainly workable. So I would rate this very low priority.
But I haven’t looked at your tests and mocks in the code, so maybe what I want is already there.