nodejs/test/parallel/test-http-bind-twice.js

'use strict';
require('../common');
var assert = require('assert');
var http = require('http');

var gotError = false;

process.on('exit', function() {
  assert(gotError);
});

function dontCall() {
  assert(false);
}

var server1 = http.createServer(dontCall);
server1.listen(0, '127.0.0.1', function() {
  var server2 = http.createServer(dontCall);
  server2.listen(this.address().port, '127.0.0.1', dontCall);

  server2.on('error', function(e) {
    assert.equal(e.code, 'EADDRINUSE');
    server1.close();
    gotError = true;
  });
});