node/test/parallel/test-cluster-server-restart-none.js

'use strict';
const common = require('../common');
const assert = require('assert');
const cluster = require('cluster');

cluster.schedulingPolicy = cluster.SCHED_NONE;

if (cluster.isPrimary) {
  const worker1 = cluster.fork();
  worker1.on('listening', common.mustCall(() => {
    const worker2 = cluster.fork();
    worker2.on('exit', (code, signal) => {
      assert.strictEqual(code, 0,
                         'worker2 did not exit normally. ' +
                         `exited with code ${code}`);
      assert.strictEqual(signal, null,
                         'worker2 did not exit normally. ' +
                         `exited with signal ${signal}`);
      worker1.disconnect();
    });
  }));

  worker1.on('exit', common.mustCall((code, signal) => {
    assert.strictEqual(code, 0,
                       'worker1 did not exit normally. ' +
                       `exited with code ${code}`);
    assert.strictEqual(signal, null,
                       'worker1 did not exit normally. ' +
                       `exited with signal ${signal}`);
  }));
} else {
  const net = require('net');
  const server = net.createServer();
  server.listen(0, common.mustCall(() => {
    if (cluster.worker.id === 2) {
      server.close(() => {
        server.listen(0, common.mustCall(() => {
          server.close(() => {
            process.disconnect();
          });
        }));
      });
    }
  }));
}