Folder deep-copy in NodeJS (ES7+)

copyFolder.js

'use strict';

const fs = require('fs');
const path = require('path');

/**
 * Create a folder and returns a Promise
 * @param {String} folder
 * @return {Promise}
 */
function makeFolder(folder) {
    return new Promise((resolve, reject) => {
        fs.mkdir(folder, (err) => {
            if (err && err.errno !== -17) {
                return reject(err);
            }

            resolve();
        });
    });
}

/**
 * Call a function in a promise
 * @param {Function} fn
 * @param {*} args
 * @return {Promise}
 */
function toPromise(fn, ...args) {
    return new Promise((resolve, reject) => {
        fn(...args, (err, data) => {
            if (err) {
                return reject(err);
            }

            resolve(data);
        });
    });
}

const lstat = (...args) => toPromise(fs.lstat, ...args);
const readdir = (...args) => toPromise(fs.readdir, ...args);
const copyFile = (...args) => toPromise(fs.copyFile, ...args);
const readlink = (...args) => toPromise(fs.readlink, ...args);
const symlink = (...args) => toPromise(fs.symlink, ...args);

/**
 * Copy a folder and returns a Promise
 * @param {String} src
 * @param {String} dest
 */
async function copyFolder(src, dest) {
    await makeFolder(dest);

    const files = await readdir(src);

    for (let file of files) {
        const current = await lstat(path.join(src, file));
        if (current.isDirectory()) {
            await copyFolder(path.join(src, file), path.join(dest, file));
        } else if (current.isSymbolicLink()) {
            let symlinkObj = await readlink(path.join(src, file));
            await symlink(symlinkObj, path.join(dest, file));
        } else {
            await copyFile(path.join(src, file), path.join(dest, file));
        }
    }
}

function main() {
   copyFolder('folderSrc', 'folderDest')
      .catch(console.error);
}