Test for Node.js oneshot signal handlers https://github.com/nodejs/node/issues/15654

stubborn.js

/*jslint indent: 2, maxlen: 80, node: true */
/* -*- tab-width: 2 -*- */
'use strict';

var EX = module.exports, fork = require('child_process').fork,
  equal = require('assert').deepStrictEqual,
  busyWait = true;


EX.main = function () {
  var args = process.argv.slice(2);
  if (args[0] === '--sig') { return EX.stubbornMode(args[1]); }
  EX.testMode();
};

function noop() { return; }

EX.stubbornMode = function (sig) {
  process.once('SIG' + sig, function () { console.log('Nope.'); });
  setTimeout(noop, 1e9);
  while (busyWait) { noop(); }
};

EX.testMode = function () {
  var customSignal = 'INT', activeTimers = {}, signalsSent = [],
    child = fork(module.filename, [ '--sig', customSignal ]);
  if (!(child || false).pid) { throw new Error('Unable to fork'); }
  child.spawnedAt = Date.now();

  function killSoon(sig, delaySec) {
    activeTimers[delaySec] = setTimeout(function () {
      delete activeTimers[delaySec];
      child.kill('SIG' + sig);
      signalsSent.push(sig);
    }, delaySec * 1000);
  }
  killSoon(customSignal, 0.2);
  killSoon(customSignal, 0.4);
  killSoon('KILL', 5);

  function abandonTimers() {
    Object.keys(activeTimers).forEach(function (timer) {
      clearTimeout(activeTimers[timer]);
      activeTimers[timer] = null;
    });
  }
  child.once('close', abandonTimers);

  function verifyTest(rv, sig) {
    child.closedAt = Date.now();
    equal(rv, null);
    equal(sig, 'SIG' + customSignal);
    equal(signalsSent, [ customSignal, customSignal ]);
    var childDurationSec = (child.closedAt - child.spawnedAt) / 1000;
    equal(Math.floor(childDurationSec), 0);
    console.log('+OK test passed');
  }
  child.once('close', verifyTest);
};







if (require.main === module) { EX.main(); }