Which gem is best suited to use when using ruby to test

Ruby
1

I am working in a medium sized it-company as a tester. We are currentlty
using ruby to test our product.
I wonder which gem to you prefer to use when you test?

test-unit
minitest-unit
rspec
a.s.o

2

Currently I am using Cucumber to write Acceptance tests.

If life was fair, Elvis would be alive and all the impersonators would
be
dead.

3

It depends on what kind of testing you’re doing. I tend to use
Cucumber for acceptance, and rspec for unit tests. Another great combo
is rspec’s request specs with capybara::DSL to do acceptance, and
rspec for unit tests. Or minitest for unit tests and capy::DSL for
acceptance.