gistfile1.rb

module NotMonkeyPatchable
  def method_added(name)
    @methods ||= {}

    if @methods[name] and not @unpatching
      @unpatching = true
      method = @methods[name] 
      define_method(name) { |*args, &block|
        method.bind(self).call(*args, &block)
      }
      @unpatching = false
    else
      @methods[name] = instance_method(name)
    end
  end
end

class Monkey
  extend NotMonkeyPatchable
  
  def see
    'clearly'
  end

  def do
    'do'
  end
end

class Monkey
  def see
    'patchy'
  end
end

class Monkey
  def see
    'nothing'
  end
end

require 'rspec/autorun'

describe Monkey do
  it 'should see clearly' do
    subject.see.should == 'clearly'
  end
end