ruby-on-rails - refile simple_form undefined method attachment_field

Question

ビューに refile を接続しようとしていますが、次のエラーが発生します。

ここに私のモデルがあります：

class Job < ActiveRecord::Base
  acts_as_paranoid

  acts_as_taggable
  acts_as_taggable_on :languages

  belongs_to :company
  belongs_to :category

  validates :title,
            :location,
            :category,
            :language_list,
            :short_description,
            :description,
            :application_process,
            presence: true
end

class Company < ActiveRecord::Base
  acts_as_paranoid
  has_many :jobs

  attachment :company_logo, type: :image

  validates :name, :url, :email, presence: true
end

そして simple_form ビュー (binding.pry は無視してください)

= render layout: 'header' do
  = simple_form_for(@job) do |j|
    div[class='panel-heading']
      h3[class='panel-title']
        |Position Details
    div[class='panel-body']
      = j.input :title
      = j.input :location
      = j.association :category, as: :radio_buttons
      = j.input :language_list, as: :check_boxes, collection: @tags
      = j.input :short_description
      = j.input :description, input_html: { class: 'textarea-height wysihtml5' }
      = j.input :application_process
    div[class='panel-heading']
      h3[class='panel-title']
        |Company Details
    div[class='panel-body']
      = j.simple_fields_for :company do |jc|
        = jc.input :name

        = binding.pry

        = jc.input :company_logo, as: :attachment
        = jc.input :url
        = jc.input :email
    div[class='panel-heading panel-heading-info']
      h3[class='panel-title']
        |Would you like your job posting featured?
    div[class='panel-body']
      p
        |Featured posted are promoted with additional design elements to grab the
          job seeker's attention.  This additional marketing capability can be purchased
          for an additonal $#{AppConfig.product['settings']['job_base_featured_price']}.

      = j.input :is_featured

      = j.button :button, type: 'button', class: 'btn-primary' do
        = job_posting_button_step_label
        =>
        i[class='fa fa-arrow-circle-right']

ドキュメントを解析している間、attachment_field未定義の理由がわかりません。

また、次のように初期化子 refile.rb をセットアップしています。

require 'refile/rails'
require 'refile/simple_form'

これを次のように切り替えると、ドキュメントがめちゃくちゃになっているのか、simple_form の部分が壊れているのか疑問に思っています。

= jc.input :company_logo, as: :file, direct: true, presigned: true