How do I find where a ruby method is declared?

Question

I have a ruby method (deactivate!) that is on an activeRecord class. However, I can't seem to find where that method is declared.

There have been numerous developers on this project, so it could be anywhere. There is a deactivate! on an unrelated class, but it doesn't seem to get called.

Any ideas how to find all the superclasses for an instace, or where to find the code for deactivate!?

Answer 1

First question would be: is it an actual method? Does obj.method(:deactivate!) raise an error?

If it doesn't, then you can use Method#source_location(in Ruby 1.9 only, and backports can't support it):

obj.method(:deactivate!).source_location

If it does raise a NoMethodError, it is handled via method_missing. This makes it hard to track. If it accepts arguments, I'd try sending the wrong type and using the backtrace of the raised exception.

Are you using state_machine? If you have an event transition called :deactivate, the model will have the method #deactivate! created automatically.