You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: comments_helper.rb
    path of file: ./repos/open-build-service/src/api/app/helpers/webui
    
    the code of the file until where you have to start completion: module Webui::CommentsHelper
  def comment_user_role_tit
    
  def comment_user_role_titles(comment)
    roles = []

    case
    when comment.commentable.is_a?(BsRequest)
      roles = roles_for_request(comment)
    when comment.commentable.is_a?(Project)
      roles << 'maintainer' if roles_for_project(comment).any?
    when comment.commentable.is_a?(Package)
      roles << 'maintainer' if roles_for_package(comment).any?
      roles << 'project maintainer' if roles_for_project(comment).any?
    end