setTimeout bug. There is example

[alsotang]

• Version:4.2.1, 5.9.0, 6.0.0
• Platform: macos
• Subsystem:

var startTime = +new Date()
while ((new Date - startTime) < 1000) {}

setTimeout(function () {
  var startTime = +new Date()
  while ((new Date - startTime) < 3000) {}

  var t1= new Date
  setTimeout(function () {
    console.log(new Date - t1, 'new Date - t1') // !!!!!!!!!!diff is 3000+, should be 20+
  }, 20)
}, 20)

timediff should be 20+ms, but it would equal to the while block time.

[alsotang]

In chrome 52.0.2743.116, the result is right.

[medns]

i review timers.js@v4.5.0 code, found the following code can be cause this problem.

if (diff < msecs) {
    list.start(msecs - diff, 0);
    debug('%d list wait because diff is %d', msecs, diff);
    return;
}

change to

if (diff < msecs) {
  if (diff >= 0) {
    list.start(msecs - diff, 0);
    debug('%d list wait because diff is %d', msecs, diff);
   } else {
    list.start(msecs, 0);
  }
  return;
}

can alleviate this issue

but in master version change the timeRemaining calc solve this issue

[alsotang]

here？

https://github.com/nodejs/node/blob/master/lib/timers.js#L171-L179

[alsotang]

seems v6.5.0 solved this issue, should I close this?

[benjamingr]

@alsotang can you please test on latest 5.x?

[Fishrock123]

This was fixed by 5aac4c4 which landed in v6.x here: 49a6ea1

The v5.x branch is now end-of-life and will not receive it.

As noted in #3063 (comment), this fix is not on v4.x at the current time, but should probably land at some point.

[alsotang]

ok, I start use v6.5.0 right now.