Friendly_id:slug_candidates没有正确命名slug

我的模型中有以下内容:

class Dispenser < ActiveRecord::Base

  extend FriendlyId

  friendly_id :slug_candidates, use: :slugged

  def slug_candidates
    [
      :full_name,
      [:full_name, :id]
    ]
  end

end

这会产生像下面这样的slu ::

=> 'bob-barker-bob-barker-15'

实际上它应该是bob-barker或bob-barker-15,但不能同时使用.

https://github.com/norman/friendly_id