test: fix cluster-worker-wait-server-close races

Wait for data to arrive from worker before doing a disconnect. Without
this, whether the disconnect arrives at the worker before the master
accepts and forwards the connection descriptor to the worker is a race.

test/parallel/test-cluster-worker-wait-server-close.js

@@ -8,7 +8,9 @@ var net = require('net');
 if (cluster.isWorker) {
  net.createServer(function(socket) {
  // Wait for any data, then close connection
- socket.on('data', socket.end.bind(socket));
+ socket.write('.');
+ socket.on('data', function discard() {
+ });
  }).listen(common.PORT, common.localhostIPv4);
 } else if (cluster.isMaster) {
 
@@ -22,11 +24,15 @@ if (cluster.isWorker) {
  worker.once('listening', function() {
  net.createConnection(common.PORT, common.localhostIPv4, function() {
  var socket = this;
- worker.disconnect();
- setTimeout(function() {
- socket.write('.');
- connectionDone = true;
- }, 1000);
+ this.on('data', function() {
+ console.log('got data from client');
+ // socket definitely connected to worker if we got data
+ worker.disconnect();
+ setTimeout(function() {
+ socket.end();
+ connectionDone = true;
+ }, 1000);
+ });
  });
  });