i18n translation missing monkey patch

i18n_ex.rb

module I18nCustom
  def self.included(base)
    base.send :alias_method_chain, :html_message, :data_attributes
  end

  def html_message_with_data_attributes
    keys.shift # discard the locale
    key = keys.last.to_s.gsub('_', ' ').gsub(/\b('?[a-z])/) { $1.capitalize }
    translation_key = keys.join('.')
    text_to_translate = I18n.t translation_key, :locale => I18n.default_locale, :default => ''
    "<span class=\"translation_missing\" data-translation-key=\"#{translation_key}\" data-translation-text=\"#{text_to_translate}\">#{key}</span>"
  end
end

I18n::MissingTranslationData.send :include, I18nCustom