Without the self[:attr] form of referencing the attribute the tests fail because the values cant be found after being set ie: disapproved_by = user.id # or @disapproved_by = user.id # or self.disapproved_by = user.id # or

gistfile1.txt

# Requires on the model that mixes this concern in:
# => approved_by integer
# => approved_at DateTime
# => disapproved_by integer
# => disapproved_at DateTime

module Moderation
  extend ActiveSupport::Concern
  
  included do
    belongs_to :approved_by,    class_name: "User", foreign_key: :approved_by
    belongs_to :disapproved_by, class_name: "User", foreign_key: :disapproved_by
    
    scope :approved,    where("approved_at IS NOT NULL")
    scope :disapproved, where("disapproved_at IS NOT NULL")
  end
  
  def published?
    self[:disapproved_at].blank?
  end

  def approve!(user)
    self[:disapproved_by] = self[:disapproved_at] = nil
    self[:approved_by]    = user.id
    self[:approved_at]    = DateTime.now.utc
    save
  end

  def dissaprove!(user)
    self[:approved_by]    = self[:approved_at] = nil
    self[:disapproved_by] = user.id
    self[:disapproved_at] = DateTime.now.utc
    save
  end
end