Wait until server is closed before invoking callback

Author: Pwndrian

lib/portfinder.js

@@ -39,8 +39,10 @@ internals.testPort = function(options, callback) {
     debugTestPort("done w/ testPort(): OK", options.host, "port", options.port);
 
     options.server.removeListener('error', onError);
-    options.server.close();
-    callback(null, options.port);
+    options.server.close(function () {
+      debugTestPort("done w/ testPort(): Server closed", options.host, "port", options.port);
+      callback(null, options.port);
+    });
   }
 
   function onError (err) {