Gem::Commands::UpdateCommand#preparing_gem_layout_for

# File tmp/rubies/ruby-4.0.0/lib/rubygems/commands/update_command.rb, line 195
def preparing_gem_layout_for(version)
  if Gem::Version.new(version) >= Gem::Version.new("3.2.a")
    yield
  else
    require "tmpdir"
    Dir.mktmpdir("gem_update") do |tmpdir|
      FileUtils.mv Gem.plugindir, tmpdir

      status = yield

      unless status
        FileUtils.mv File.join(tmpdir, "plugins"), Gem.plugindir
      end

      status
    end
  end
end