class RuboCop::Cop::AnnotationComment

def regex
  KEYWORDS_REGEX_CACHE[keywords] ||= begin
    keywords_regex = Regexp.new(
      Regexp.union(keywords.sort_by { |w| -w.length }).source,
      Regexp::IGNORECASE
    )
    /^(# ?)(\b#{keywords_regex}\b)(\s*:)?(\s+)?(\S+)?/i
  end
end