Ruby on rails 无法加载这样的文件--activerecord（LoadError）

我正在尝试将一个非常旧的应用程序从Rails 2.3.12升级到Rails 3.0.0（作为将其升级到Rails 4的起点）。我一直在慢慢地通过移除旧宝石等方式修复升级后损坏的任何东西

我遇到了一个似乎无法解决的问题

我在运行轨道3，Ruby1.9.3

尝试运行rails服务器时，出现以下错误：

    => Booting WEBrick
=> Rails 3.0.0 application starting in development on http://0.0.0.0:3000
=> Call with -d to detach
=> Ctrl-C to shutdown server
Exiting
/home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:239:in `require': cannot load such file -- activerecord (LoadError)
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:239:in `block in require'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:225:in `block in load_dependency'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:591:in `new_constants_in'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:225:in `load_dependency'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:239:in `require'
        from /home/camillavk/Documents/Work/Saild/saild/vendor/plugins/acts_as_commentable/lib/commentable_methods.rb:1:in `<top (required)>'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:239:in `require'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:239:in `block in require'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:225:in `block in load_dependency'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:591:in `new_constants_in'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:225:in `load_dependency'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:239:in `require'
        from /home/camillavk/Documents/Work/Saild/saild/vendor/plugins/acts_as_commentable/lib/acts_as_commentable.rb:1:in `<top (required)>'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:239:in `require'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:239:in `block in require'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:225:in `block in load_dependency'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:591:in `new_constants_in'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:225:in `load_dependency'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:239:in `require'
        from /home/camillavk/Documents/Work/Saild/saild/vendor/plugins/acts_as_commentable/rails/init.rb:1:in `block in <class:Plugin>'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/railties-3.0.0/lib/rails/plugin.rb:81:in `eval'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/railties-3.0.0/lib/rails/plugin.rb:81:in `block in <class:Plugin>'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/railties-3.0.0/lib/rails/initializable.rb:25:in `instance_exec'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/railties-3.0.0/lib/rails/initializable.rb:25:in `run'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/railties-3.0.0/lib/rails/initializable.rb:50:in `block in run_initializers'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/railties-3.0.0/lib/rails/initializable.rb:49:in `each'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/railties-3.0.0/lib/rails/initializable.rb:49:in `run_initializers'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/railties-3.0.0/lib/rails/application.rb:134:in `initialize!'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/railties-3.0.0/lib/rails/application.rb:77:in `method_missing'
        from /home/camillavk/Documents/Work/Saild/saild/config/environment.rb:7:in `<top (required)>'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:239:in `require'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:239:in `block in require'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:225:in `block in load_dependency'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:591:in `new_constants_in'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:225:in `load_dependency'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:239:in `require'
        from /home/camillavk/Documents/Work/Saild/saild/config.ru:3:in `block in <main>'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/rack-1.2.8/lib/rack/builder.rb:46:in `instance_eval'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/rack-1.2.8/lib/rack/builder.rb:46:in `initialize'
        from /home/camillavk/Documents/Work/Saild/saild/config.ru:1:in `new'
        from /home/camillavk/Documents/Work/Saild/saild/config.ru:1:in `<main>'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/rack-1.2.8/lib/rack/builder.rb:35:in `eval'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/rack-1.2.8/lib/rack/builder.rb:35:in `parse_file'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/rack-1.2.8/lib/rack/server.rb:162:in `app'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/rack-1.2.8/lib/rack/server.rb:253:in `wrapped_app'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/rack-1.2.8/lib/rack/server.rb:204:in `start'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/railties-3.0.0/lib/rails/commands/server.rb:65:in `start'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/railties-3.0.0/lib/rails/commands.rb:30:in `block in <top (required)>'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/railties-3.0.0/lib/rails/commands.rb:27:in `tap'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/railties-3.0.0/lib/rails/commands.rb:27:in `<top (required)>'
        from script/rails:6:in `require'
        from script/rails:6:in `<main>'

在升级到Rails 3之前，还有其他人遇到过这个问题吗？我在谷歌上找不到关于它的任何信息

或者是否有人对我如何发现/解决问题提出建议

---

非常感谢

让我们看看您的堆栈跟踪。堆栈跟踪从上到下读取。如果有函数A调用函数B调用函数C，则在发生错误时，堆栈跟踪显示

C
B
A

我们可以看到，第一行都来自Rails本身：

/home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:239:in `require': cannot load such file -- activerecord (LoadError)
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:239:in `block in require'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:225:in `block in load_dependency'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:591:in `new_constants_in'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:225:in `load_dependency'
        from /home/camillavk/.rvm/gems/ruby-1.9.3-p551@rails3/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:239:in `require'

由于Rails本身通常不太可能是罪魁祸首，因此我们会寻找来自其他地方的第一行代码——您自己的代码或第三方库

下一行就是：

        from /home/camillavk/Documents/Work/Saild/saild/vendor/plugins/acts_as_commentable/lib/commentable_methods.rb:1:in `<top (required)>'

from/home/camillavk/Documents/Work/Saild/Saild/vendor/plugins/acts\u as\u commentable/lib/commentable\u methods.rb:1:in`'

我们在

vendor/plugins

上看到了它的代码，这使它成为一个旧的、Rails 2.3风格的插件。它们在中被弃用，并完全停止在Rails 4中工作。它们被通过Gemfile和Bundler添加的“Gem插件”取代，而不是

供应商/插件

---

因此，

扮演可评论的角色

是罪魁祸首的最佳人选。该页面显示了一个专门针对Rails 3的版本，因此删除旧插件并用该Gem替换它可以很好地解决此问题。

看起来错误发生在一个名为

的旧的Rails 2.3风格插件中，该插件可作为可注释的
。尝试删除
vendor/plugins/acts\u as\u commentable
并将其Rails 3后续版本添加到您的gem文件中：
gem'acts\u as\u commentable'，'3.0.1'
我将给出一个答案，并尝试解释一下我是如何找到它的。你可能会遇到更多这样的情况。祝你移民好运！那太棒了！我一直在设法猜测错误在哪里，并将它们拼凑在一起，但我并没有真正理解插件和gems之间的区别，因为我以前没有遇到过Rails 2或3（Rails非常新！），所以我自己无法解决这个问题：-）好吧，如果我理解正确，我最终需要浏览所有的供应商/插件文件夹，为每个文件夹找到新的Rails 3 gem版本？恐怕没有办法，是的……你有很多吗？大约有20个……哦，好吧，我想我知道我周五下午剩下的时间在做什么！：-D
        from /home/camillavk/Documents/Work/Saild/saild/vendor/plugins/acts_as_commentable/lib/commentable_methods.rb:1:in `<top (required)>'