if !defined? RSpec say "RSpec was not installed. Adding it now..." gem "rspec-rails" , group: [:development, :test] run "bundle install" generate "rspec:install" end gem 'shoulda-matchers', group: [:test] run 'bundle install' inject_into_file 'spec/rails_helper.rb', after: '# config.filter_gems_from_backtrace("gem name")' + "\nend" do <<~EOF \n Shoulda::Matchers.configure do |config| config.integrate do |with| with.test_framework :rspec with.library :rails end end EOF end