class Gem::Commands::UpdateCommand

def install_rubygems(spec) # :nodoc:
  args = update_rubygems_arguments
  version = spec.version
  update_dir = File.join spec.base_dir, "gems", "rubygems-update-#{version}"
  Dir.chdir update_dir do
    say "Installing RubyGems #{version}" unless options[:silent]
    installed = preparing_gem_layout_for(version) do
      system Gem.ruby, "--disable-gems", "setup.rb", *args
    end
    unless options[:silent]
      say "RubyGems system software updated" if installed
    end
  end
end