I wanted to write out a full reply rather than continue a back-and-forth Twitter conversation. I don't want to be "that guy" that publicly does a "drive-by-shit-on" regarding an open-source project. I realize how much time and effort it takes to keep a project like minitest-rails running!
I think my problem with minitest-rails is part philosophical, part practical. Practically, it was a bitch to get working. That's weird to me. I figured the point of minitest-rails would be to just drop it into my Rails project's gemfile and minitest should "just work". But after about 3 hours of trying, it just wouldn't. I ended up writing my own helpers to get minitest working with Rails, and it ended up being a) simpler than I expected, and b) much clearer than what minitest-rails was doing. I'm sure I maybe just missed a few details here and there with minitest-rails that prevented my tests from working, but I'll attach the very minimal code that was required to get minitest working. My question is - why can't minitest rails just do that, add some generators, and let me get on with my life?
Philosophically, I do find it strange that the base minitest-rails class inherits from the Spec DSL rather than the base Minitest class. I couldn't get non-spec-syntax tests working, I figured it was because of this inheritance. Maybe I was wrong, but when I dove into the Minitest-rails source and saw that inheritance, I just figured non-Spec-syntax tests were not supported.
Also philosophically, the whole reason I'm switching to minitest in the first place was because I was frustrated with how much Rspec was "doing for me". As a testimonial in the minitest README says, "Rspec is a testing DSL, minitest is just ruby". I wish that kind of philosophy was evident in minitest-rails, but I just didn't feel like it is.
Anyway, those are my limited impressions from futzing with minitest-rails for 3 hours. I've attached the code I used to get minitest working for me without minitest-rails as a reference. At the end of the day, maybe this is just a documentation problem. An example Rails project with some minitest-rails examples would have been very helpful.