我正在尝试运行自动测试，有一次它正在为我工作然后停止。我一直在关注ruby on rails教程。
lexi87$ autotest
Invalid gemspec in [/Users/lexi87/.rvm/gems/ruby-1.9.3-p374/specifications/ZenTest-4.8.4.gemspec]: Illformed requirement ["< 2.1, >= 1.8"]
Invalid gemspec in [/Users/lexi87/.rvm/gems/ruby-1.9.3-p374/specifications/ZenTest-4.8.4.gemspec]: Illformed requirement ["< 2.1, >= 1.8"]
loading autotest/rspec2
/Users/lexi87/rails_projects/sample_app/.autotest:1:in `require': cannot load such file -- autotest/growl (LoadError)
from /Users/lexi87/rails_projects/sample_app/.autotest:1:in `<top (required)>'
from /Users/lexi87/.rvm/gems/ruby-1.9.3-p374/gems/ZenTest-4.8.3/lib/autotest.rb:315:in `load'
因此，如果有人可以提供正确的步骤，让自动测试工作，这将是伟大的！感谢