'use strict'; const common = require('../common'); const assert = require('assert'); const net = require('net'); function check(addressType, cb) { const server = net.createServer(function(client) { client.end(); server.close(); cb && cb(); }); const address = addressType === 4 ? common.localhostIPv4 : '::1'; server.listen(0, address, common.mustCall(function() { net.connect({ port: this.address().port, host: 'localhost', family: addressType, lookup: lookup }).on('lookup', common.mustCall(function(err, ip, type) { assert.strictEqual(err, null); assert.strictEqual(address, ip); assert.strictEqual(type, addressType); })); })); function lookup(host, dnsopts, cb) { dnsopts.family = addressType; if (addressType === 4) { process.nextTick(function() { cb(null, common.localhostIPv4, 4); }); } else { process.nextTick(function() { cb(null, '::1', 6); }); } } } check(4, function() { common.hasIPv6 && check(6); });