# File lib/commands/plugin/rails_environment.rb, line 76
  def externals=(items)
    unless items.is_a? String
      items = items.map{|name,uri| "#{name.ljust(29)} #{uri.chomp('/')}"}.join("\n")
    end
    Tempfile.open("svn-set-prop") do |file|
      file.write(items)
      file.flush
      system("svn propset -q svn:externals -F \"#{file.path}\" \"#{root}/vendor/plugins\"")
    end
  end