JavaScript seconds to time string with format hh:mm:ss

Question

I want to convert a duration of time, i.e., number of seconds to colon-separated time string (hh:mm:ss)

I found some useful answers here but they all talk about conv

Answer 1

Here's my take on it:

function formatTime(seconds) {
  const h = Math.floor(seconds / 3600);
  const m = Math.floor((seconds % 3600) / 60);
  const s = Math.round(seconds % 60);
  return [
    h,
    m > 9 ? m : (h ? '0' + m : m || '0'),
    s > 9 ? s : '0' + s
  ].filter(Boolean).join(':');
}

Expected results:

const expect = require('expect');
expect(formatTime(0)).toEqual('0:00');
expect(formatTime(1)).toEqual('0:01');
expect(formatTime(599)).toEqual('9:59');
expect(formatTime(600)).toEqual('10:00');
expect(formatTime(3600)).toEqual('1:00:00');
expect(formatTime(360009)).toEqual('100:00:09');
expect(formatTime(0.2)).toEqual('0:00');