# File lib/nanoc/cli/error_handler.rb, line 181
    def gems_and_versions
      gems = {}
      Gem::Specification.find_all.sort_by { |s| [ s.name, s.version ] }.each do |spec|
        gems[spec.name] ||= []
        gems[spec.name] << spec.version.to_s
      end
      gems
    end