Como validar CPF javascript nodejs

cpf.js

const readline = require("readline");
const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout
});

function digitResover(val) {
    // LM = 11k + r
    const k = 11; // Quociente
    const r = val%k; // Resto
    
    if (r == 0 || r == 1) {
        return 0;
    }
    
    return k-r;
}

function calcL(d) {
    const L = 10*d[0]+
    9*d[1]+
    8*d[2]+
    7*d[3]+
    6*d[4]+
    5*d[5]+
    4*d[6]+
    3*d[7]+
    2*d[8];
    
    return digitResover(L);
}

function calcM(d) {
    const M = 10*d[1]+
    9*d[2]+
    8*d[3]+
    7*d[4]+
    6*d[5]+
    5*d[6]+
    4*d[7]+
    3*d[8]+
    2*d[9];
    
    return digitResover(M);
}

function check(cpfVal) {
    const digits = cpfVal.split("");
    
    if ( 
        digits[9] == calcL(digits) &&
        digits[10] == calcM(digits)
        ) {
            return true;
        }
        
    return false;
}

rl.question("CPF: ", function (digits) {
    console.log( check(digits) )
    
    rl.close()
});