rspec subject with factorygirl

factory_girl.rb

module FactoryGirlHelpers

  # extract subject attributes and produce factory object from them
  #
  # @example subject_factory(:build_stubbed)
  # @example subject_factory(:create, :comment_reply)
  def subject_factory(method, factory_name = nil)
    changed_attrbiutes = subject.changed
    attributes = subject.attributes.slice changed_attrbiutes

    factory_name ||= subject.class.to_s.parameterize

    FactoryGirl.public_send method, factory_name, attributes
  end
end

RSpec.configure do |config|
  include FactoryGirlHelpers
end