How do I see where in the Class Hierarchy a Method was defined and Overridden in Ruby?

Question

Is there a way to know whether or not a method has been overridden by a subclass programmatically? Something that works like this:

class BaseModel
  def create
    puts "superclass"
  end
end

class SomeModel < BaseModel
  def create
    puts "subclass"
  end
end

puts SomeModel.overridden_instance_methods #=> [:create]

Any ideas?

Answer 1

SomeModel.instance_methods(false) & BaseModel.instance_methods

The false makes instance_methods not include inherited methods. We then use set intersection to find all the methods that were defined on SomeModel which have previously been defined on BaseModel (or Object).