Test::unit and Rubymine "No tests were found"

I'm a newbie in Ruby and I try to use the test::unit framework with the RubyMine IDE (3.1.1).

I don't understand the note about test::unit here: http://www.jetbrains.com/ruby/webhelp/test-unit-special-note.html

Specially this instruction: "Include test-unit gem in your Gemfile." I use gem install "test-unit" and attach it to my project but I still got 0 tests and the error message "No tests were found"

Make sure that you have a Gemfile in your project root which contains:

gem 'test-unit'

There is another reason that can cause some scenario not to be recognized. If there is an scenario with the same name in other feature, it may cause your scenario not to be detected.