render_once.rb

# spec/spec_helper.rb

module RSpec::Rails::ViewExampleGroup::ExampleMethods
  def render_once(*args, &block)
    _rendered = self.class.instance_variable_get(:'@__rendered_once__')
    _doc = self.class.instance_variable_get(:'@__doc_once__')
    _view = self.class.instance_variable_get(:'@__view_once__')

    if _rendered && _view
      @rendered = _rendered
      @view = _view
    else
      render(*args, &block)
      self.class.instance_variable_set(:'@__rendered_once__', rendered)
      self.class.instance_variable_set(:'@__view_once__', view)
    end

    if _doc
      @doc = _doc
    else
      @doc = self.class.instance_variable_set(:'@__doc_once__', Nokogiri::HTML(@rendered))
    end
  end
end