node/test/mjsunit/test-timers.js

include("mjsunit.js");

var WINDOW = 800; // why is does this need to be so big?

var interval_count = 0;
var setTimeout_called = false;

function onLoad () {
  assertInstanceof(setTimeout, Function);
  var starttime = new Date;

  setTimeout(function () {
    var endtime = new Date;
    var diff = endtime - starttime;
    if (diff < 0) diff = -diff;
    assertTrue(1000 - WINDOW < diff && diff < 1000 + WINDOW);
    setTimeout_called = true;
  }, 1000);

  // this timer shouldn't execute
  var id = setTimeout(function () { assertTrue(false); }, 500);
  clearTimeout(id);

  setInterval(function () {
    interval_count += 1;
    var endtime = new Date;
    var diff = endtime - starttime;
    if (diff < 0) diff = -diff;

    var t = interval_count * 1000;

    assertTrue(t - WINDOW < diff && diff < t + WINDOW);
    
    assertTrue(interval_count <= 3);
    if (interval_count == 3)
      clearInterval(this);
  }, 1000);
}

function onExit () {
  assertTrue(setTimeout_called);
  assertEquals(3, interval_count);
}