我刚开始使用Ruby / Rails并且正在浏览一个示例应用程序。一切正常，直到我将OSX升级到El Capitan然后它不再有效。
我卸载了ruby，自制软件，rbenv，rails等...并重新安装了新的。
rails new testapp
...
...
create vendor/assets/javascripts/.keep
create vendor/assets/stylesheets
create vendor/assets/stylesheets/.keep
run bundle install
/usr/local/lib/ruby/site_ruby/2.2.0/rubygems/core_ext/kernel_require.rb:128:in `require': cannot load such file -- bundler (LoadError)
from /usr/local/lib/ruby/site_ruby/2.2.0/rubygems/core_ext/kernel_require.rb:128:in `rescue in require'
from /usr/local/lib/ruby/site_ruby/2.2.0/rubygems/core_ext/kernel_require.rb:39:in `require'
from /usr/local/lib/ruby/gems/2.2.0/gems/railties-4.2.4/lib/rails/generators/app_base.rb:319:in `bundle_command'
from /usr/local/lib/ruby/gems/2.2.0/gems/railties-4.2.4/lib/rails/generators/app_base.rb:335:in `run_bundle'
from (eval):1:in `run_bundle'
from /usr/local/lib/ruby/gems/2.2.0/gems/thor-0.19.1/lib/thor/command.rb:27:in `run'
from /usr/local/lib/ruby/gems/2.2.0/gems/thor-0.19.1/lib/thor/invocation.rb:126:in `invoke_command'
from /usr/local/lib/ruby/gems/2.2.0/gems/thor-0.19.1/lib/thor/invocation.rb:133:in `block in invoke_all'
from /usr/local/lib/ruby/gems/2.2.0/gems/thor-0.19.1/lib/thor/invocation.rb:133:in `each'
from /usr/local/lib/ruby/gems/2.2.0/gems/thor-0.19.1/lib/thor/invocation.rb:133:in `map'
from /usr/local/lib/ruby/gems/2.2.0/gems/thor-0.19.1/lib/thor/invocation.rb:133:in `invoke_all'
from /usr/local/lib/ruby/gems/2.2.0/gems/thor-0.19.1/lib/thor/group.rb:232:in `dispatch'
from /usr/local/lib/ruby/gems/2.2.0/gems/thor-0.19.1/lib/thor/base.rb:440:in `start'
from /usr/local/lib/ruby/gems/2.2.0/gems/railties-4.2.4/lib/rails/commands/application.rb:17:in `<top (required)>'
from /usr/local/lib/ruby/site_ruby/2.2.0/rubygems/core_ext/kernel_require.rb:69:in `require'
from /usr/local/lib/ruby/site_ruby/2.2.0/rubygems/core_ext/kernel_require.rb:69:in `require'
from /usr/local/lib/ruby/gems/2.2.0/gems/railties-4.2.4/lib/rails/cli.rb:14:in `<top (required)>'
from /usr/local/lib/ruby/site_ruby/2.2.0/rubygems/core_ext/kernel_require.rb:69:in `require'
from /usr/local/lib/ruby/site_ruby/2.2.0/rubygems/core_ext/kernel_require.rb:69:in `require'
from /usr/local/lib/ruby/gems/2.2.0/gems/railties-4.2.4/bin/rails:9:in `<top (required)>'
from /usr/local/bin/rails:23:in `load'
from /usr/local/bin/rails:23:in `<main>'
有什么想法吗？ THX。