intermittent unexpected socket closure on Mac OS X

[Trott]

Ref: #1100
Ref: nodejs/node-v0.x-archive#16805

The following code will throw on OS X. It might take a while but it will happen. I usually see the error before runcount hits 2000.

'use strict';
const fork = require('child_process').fork;
const net = require('net');
const count = 12;
const port = 12346;

if (process.argv[2] === 'child') {
 let sockets = [];

 process.on('message', function(m, socket) {
 function sendClosed(id) {
 process.send({ id: id, status: 'closed'});
 };

 if (m.cmd === 'new') {
 sockets.push(socket);
 }

 if (m.cmd === 'close') {
 if (sockets[m.id].destroyed) {
 throw new Error('socket already destroyed');
 }
 sockets[m.id].once('close', sendClosed.bind(null, m.id));
 sockets[m.id].destroy();
 }

 if (m.cmd === 'clear') {
 sockets = [];
 }
 });

} else {
 const child = fork(process.argv[1], ['child']);

 const server = net.createServer();
 let sockets = [];

 server.on('connection', function(socket) {
 child.send({ cmd: 'new' }, socket);
 sockets.push(socket);

 if (sockets.length === count) {
 closeSockets(0);
 }
 });

 function createSockets() {
 let j = count, client;
 while (j--) {
 client = net.connect(port, '127.0.0.1');
 }
 }

 server.on('listening', function() {
 createSockets();
 });

 let runCount = 0;
 function closeSockets(i) {
 if (i === count) {
 console.log('run count: ' + ++runCount);
 child.send({ cmd: 'clear' });
 sockets = [];
 return createSockets();
 }

 child.once('message', function(m) {
 server.getConnections(function(err, num) {
 closeSockets(i + 1);
 });
 });
 child.send({ id: i, cmd: 'close' });
 };

 server.listen(port, '127.0.0.1');
}

[brendanashworth]

@Trott any chance we could stick a loop inside the test? That way the error is easier to reproduce?