我在下载的测试应用中没有任何功能。我还没写过代码。我运行rake cucumber来测试它是否正常工作，它给了我以下错误。
/home/user/.rvm/gems/ruby-2.2.1/gems/activesupport-3.2.18/lib/active_support/values/time_zone.rb:270: warning: circular argument reference - now
/home/user/.rvm/rubies/ruby-2.2.1/bin/ruby -S bundle exec cucumber --profile default
/home/user/.rvm/gems/ruby-2.2.1/gems/cucumber-1.3.15/lib/cucumber/ast/step.rb:80: warning: circular argument reference - name
/home/user/.rvm/gems/ruby-2.2.1/gems/activesupport-3.2.18/lib/active_support/values/time_zone.rb:270: warning: circular argument reference - now
cannot load such file -- test/unit (LoadError)
/home/user/.rvm/gems/ruby-2.2.1/gems/activesupport-3.2.18/lib/active_support/dependencies.rb:251:in `require'
/home/user/.rvm/gems/ruby-2.2.1/gems/activesupport-3.2.18/lib/active_support/dependencies.rb:251:in `block in require'
/home/user/.rvm/gems/ruby-2.2.1/gems/activesupport-3.2.18/lib/active_support/dependencies.rb:236:in `load_dependency'
/home/user/.rvm/gems/ruby-2.2.1/gems/activesupport-3.2.18/lib/active_support/dependencies.rb:251:in `require'
/home/user/.rvm/gems/ruby-2.2.1/gems/railties-3.2.18/lib/rails/test_help.rb:5:in `<top (required)>'
/home/user/.rvm/gems/ruby-2.2.1/gems/activesupport-3.2.18/lib/active_support/dependencies.rb:251:in `require'
/home/user/.rvm/gems/ruby-2.2.1/gems/activesupport-3.2.18/lib/active_support/dependencies.rb:251:in `block in require'
/home/user/.rvm/gems/ruby-2.2.1/gems/activesupport-3.2.18/lib/active_support/dependencies.rb:236:in `load_dependency'
/home/user/.rvm/gems/ruby-2.2.1/gems/activesupport-3.2.18/lib/active_support/dependencies.rb:251:in `require'
/home/user/.rvm/gems/ruby-2.2.1/gems/cucumber-rails-1.4.1/lib/cucumber/rails.rb:11:in `<top (required)>'
/home/user/SE/bdd-tdd-cycle/rottenpotatoes/features/support/env.rb:7:in `require'
/home/user/SE/bdd-tdd-cycle/rottenpotatoes/features/support/env.rb:7:in `<top (required)>'
/home/user/.rvm/gems/ruby-2.2.1/gems/cucumber-1.3.15/lib/cucumber/rb_support/rb_language.rb:95:in `load'
/home/user/.rvm/gems/ruby-2.2.1/gems/cucumber-1.3.15/lib/cucumber/rb_support/rb_language.rb:95:in `load_code_file'
/home/user/.rvm/gems/ruby-2.2.1/gems/cucumber-1.3.15/lib/cucumber/runtime/support_code.rb:180:in `load_file'
/home/user/.rvm/gems/ruby-2.2.1/gems/cucumber-1.3.15/lib/cucumber/runtime/support_code.rb:83:in `block in load_files!'
/home/user/.rvm/gems/ruby-2.2.1/gems/cucumber-1.3.15/lib/cucumber/runtime/support_code.rb:82:in `each'
/home/user/.rvm/gems/ruby-2.2.1/gems/cucumber-1.3.15/lib/cucumber/runtime/support_code.rb:82:in `load_files!'
/home/user/.rvm/gems/ruby-2.2.1/gems/cucumber-1.3.15/lib/cucumber/runtime.rb:184:in `load_step_definitions'
/home/user/.rvm/gems/ruby-2.2.1/gems/cucumber-1.3.15/lib/cucumber/runtime.rb:42:in `run!'
/home/user/.rvm/gems/ruby-2.2.1/gems/cucumber-1.3.15/lib/cucumber/cli/main.rb:47:in `execute!'
/home/user/.rvm/gems/ruby-2.2.1/gems/cucumber-1.3.15/bin/cucumber:13:in `<top (required)>'
/home/user/.rvm/gems/ruby-2.2.1/bin/cucumber:23:in `load'
/home/user/.rvm/gems/ruby-2.2.1/bin/cucumber:23:in `<main>'
/home/user/.rvm/gems/ruby-2.2.1/bin/ruby_executable_hooks:15:in `eval'
/home/user/.rvm/gems/ruby-2.2.1/bin/ruby_executable_hooks:15:in `<main>'
有人能告诉我发生了什么事吗？ 这个问题的解决方案是什么？理想情况下，它应该输出没有可用的测试并且通过了0/0步骤。