Convertion from HH:MM:SS to seconds - inspired by this answer https://stackoverflow.com/a/9640417

hmsToSeconds.js

/**
 * @description convert hms string to seconds
 * @see performance test with jsBench: https://jsbench.me/rckgfk8iv7
 * @license MIT
 *
 * @param {String} str HH:MM:SS
 * @example str = '01:00:10' return 3610
 * @returns {Number} time as seconds
 */
const hmsToSeconds = (str) => {
    str = str.split(':').reverse();
    let m = [1, 60, 3600];
    let sec = 0;

    for(t in str){
        sec += (+str[t]) * m[t]
    }
    return sec
}

Its made to be able to use anything like:

hmsToSenconds('01:00:10')
hmsToSenconds('00:10')
hmsToSenconds('10')