module Hoe::Package

def install_gem name, version = nil, rdoc = true
  should_not_sudo = Hoe::WINDOZE || ENV["NOSUDO"] || File.writable?(Gem.dir)
  null_dev = Hoe::WINDOZE ? "> NUL 2>&1" : "> /dev/null 2>&1"
  gem_cmd = Gem.default_exec_format % "gem"
  sudo    = "sudo "                  unless should_not_sudo
  local   = "--local"                unless version
  version = "--version '#{version}'" if     version
  cmd  = "#{sudo}#{gem_cmd} install #{local} #{name} #{version}"
  cmd += " --no-document" unless rdoc
  cmd += " #{null_dev}" unless Rake.application.options.trace
  puts cmd if Rake.application.options.trace
  system cmd
end