lib/mongoid/slug.rb
def build_slug
      if localized?
        begin
          orig_locale = I18n.locale
          all_locales.each do |target_locale|
            I18n.locale = target_locale
            apply_slug
          end
        ensure
          I18n.locale = orig_locale
        end
      else
        apply_slug
      end
      true
    end
def build_slug
      if localized?
        begin
          orig_locale = I18n.locale
          all_locales.each do |target_locale|
            I18n.locale = target_locale
            apply_slug
          end
        ensure
          I18n.locale = orig_locale
        end
      else
        apply_slug
      end
      true
    end
Builds a new slug.

 @return [true]