class Gem::Commands::SetupCommand

def install_lib(lib_dir)
  say "Installing RubyGems" if @verbose
  lib_files = rb_files_in 'lib'
  Dir.chdir 'lib' do
    lib_files.each do |lib_file|
      dest_file = File.join lib_dir, lib_file
      dest_dir = File.dirname dest_file
      mkdir_p dest_dir unless File.directory? dest_dir
      install lib_file, dest_file, :mode => 0644
    end
  end
end