PadEnd & PadStart

function padEnd (str, length, padStr = ' ') {
    if (str.length < length) {
        let rem = length - str.length;
        if (rem > padStr.length) {
            let temp = str + padStr;
            while (temp.length < length) {
                temp += padStr;
            }
            if (temp.length > length) {
                return temp.substring(0, length);
            }
            return temp;
        } else {
            return str + padStr.substring(0, rem.length);
        }
    }
    return str;
}

function padStart (str, length, padStr = ' ') {
    if (str.length < length) {
        let rem = length - str.length;
        if (rem > padStr.length) {
            let temp = padStr;
            while (temp.length < rem) {
                temp += padStr;
            }
            if (temp.length > rem) {
                return temp.substring(0, rem) + str;
            }
            return temp + str;
        } else {
            return padStr.substring(0, rem.length - str.length) + str;
        }
    }
    return str;
}


let myStr = "_bob_";
let pad = "wow";

let str1 = padStart(myStr, 10, pad);
let str2 = padEnd(myStr, 10, pad);

console.log(str1);
console.log(str2);