PHPass 64-encoding conversion

conver.js

const phpassbase64 = './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';

const base64translate = (input) => {
    const res = [0];
    let currentBit = 0, index = 0;
    input.split('').forEach(l => {
        const i = phpassbase64.indexOf(l);
        res[index] += (i << currentBit) & 0xff;
        currentBit += 6;
        if(currentBit >= 8) {
            currentBit -= 8;
            index++;
            res.push(i >> (6-currentBit));
        }
    });
    if(res[res.length - 1] === 0)
        res.pop();
    return Buffer.from(res);
}