watch *.p[lm] and *.t then notify test results

watchr.rb

watch('(.*).(p[ml])') { |m| code_changed(m[0]) }
watch('(.*).t') { |m| code_changed(m[0]) }

def code_changed(file)
    run "prove -cv"
end

def run(cmd)
  result = `#{cmd}`
    growl result rescue nil
end

def growl(message)
  puts(message)
  message = message.split("\n").last(2);
  osn = Config::CONFIG["target_os"].downcase
  growlnotify = `which growlnotify`.chomp if osn.include?("darwin")
  growlnotify = `which notify-send`.chomp if osn.include?("linux")

  title = message.find { |e| /Result:\sFAIL/ =~ e } ? "FAILURES" : "PASS"
  info = message[0]
  options = "-n Watchr '#{title}' -m '#{info}'" if osn.include?("darwin")
  options = "'#{title}' '#{info}'" if osn.include?("linux")
  system %(#{growlnotify} #{options} &)
end