class RSpec::Mocks::MethodDouble

def stash_original_method
  if object_responds_to?(@method_name)
    stashed = stashed_method_name
    orig = @method_name
    object_singleton_class.class_eval do
      alias_method(stashed, orig) if method_defined?(orig) || private_method_defined?(orig)
    end
    @stashed = true
  end
end