gistfile1.rb

  def details
    original_details = read_attribute(:details) 
    value = original_details.blank? ? product.try(:details) : original_details
    value ||= ""

    if alcohol_by_volume.present?
      variations = ["#{alcohol_by_volume}%", "#{alcohol_by_volume}0%"]
      variations << "#{alcohol_by_volume.to_i}%" if alcohol_by_volume % 1 == 0.0
      unless variations.any? { |variation| value.to_s.include?(variation.to_s) }
        value += " #{alcohol_by_volume}% alcohol by volume."
      end
    end
    value.strip
  end