如何找出拦截'method_missing'的内容

Question

使用Ruby 1.8.6/Rails 2.3.2

我注意到在我的任何ActiveRecord模型类上调用的任何方法都返回nil而不是NoMethodError.除了恼人的,这是打破了动态查找器(find_by_name,find_by_id,等),因为他们总是返回nil即使记录存在.不从ActiveRecord :: Base派生的标准类不受影响.

有没有办法在ActiveRecord :: Base之前跟踪什么是拦截method_missing？

更新:

切换到1.8.7后,我发现(感谢@MichaelKohl)will_paginate插件首先处理method_missing.但是will_paginate在我们的系统中已经存在了很长一段时间(并且没有改变),罪魁祸首必须是后来的链接.任何想法如何看到这个链中的下一步？

更新:

事实证明,有一个gem(annotate-2.4.0)是猴子修补ActiveRecord::Base#method_missing作为一个空白的方法.卸载gem解决了我的问题.虽然没有给出的答案实际上找到了问题,但@Yanhao的答案最接近,因为它只需要一个小调整来发现有问题的别名方法

Answer 1

我认为@Sebi的回答很有帮助，但我想像这样改进它：

set_trace_func proc { |event, file, line, id, binding, classname|
  printf "%8s %s:%-2d %10s %8s\n", event, file, line, id, classname if id.to_s == 'method_missing'
}

结果是这样的：

ruby-1.8.7-p334 :036 > SomeModel.some_missing_method
    call /Users/.../.rvm/gems/ruby-1.8.7-p334/gems/activerecord-2.3.12/lib/active_record/base.rb:1873 method_missing ActiveRecord::Base
    line /Users/.../.rvm/gems/ruby-1.8.7-p334/gems/activerecord-2.3.12/lib/active_record/base.rb:1874 method_missing ActiveRecord::Base
    line /Users/.../.rvm/gems/ruby-1.8.7-p334/gems/activerecord-2.3.12/lib/active_record/base.rb:1874 method_missing ActiveRecord::Base
    line /Users/.../.rvm/gems/ruby-1.8.7-p334/gems/activerecord-2.3.12/lib/active_record/base.rb:1981 method_missing ActiveRecord::Base
    line /Users/.../.rvm/gems/ruby-1.8.7-p334/gems/activerecord-2.3.12/lib/active_record/base.rb:1998 method_missing ActiveRecord::Base
  c-call /Users/.../.rvm/gems/ruby-1.8.7-p334/gems/activerecord-2.3.12/lib/active_record/base.rb:1998 method_missing   Kernel
   raise /Users/.../.rvm/gems/ruby-1.8.7-p334/gems/activerecord-2.3.12/lib/active_record/base.rb:1998 method_missing ActiveRecord::Base
c-return /Users/.../.rvm/gems/ruby-1.8.7-p334/gems/activerecord-2.3.12/lib/active_record/base.rb:1998 method_missing   Kernel
  return /Users/.../.rvm/gems/ruby-1.8.7-p334/gems/activerecord-2.3.12/lib/active_record/base.rb:1998 method_missing ActiveRecord::Base