    # File lib/rubygems/commands/stale_command.rb, line 12
      def execute
        gem_to_atime = {}
        Gem.source_index.each do |name, spec|
          Dir["#{spec.full_gem_path}/**/*.*"].each do |file|
            next if File.directory?(file)
            stat = File.stat(file)
            gem_to_atime[name] ||= stat.atime
            gem_to_atime[name] = stat.atime if gem_to_atime[name] < stat.atime
          end
        end

        gem_to_atime.sort_by { |_, atime| atime }.each do |name, atime|
          say "#{name} at #{atime.strftime '%c'}"
        end
      end