gh-274.sh

#!/bin/bash
mkdir -p gh-274/folder1
touch gh-274/folder1/main.js
touch gh-274/index.js

tree gh-274/

node - <<JS
const tar = require('./')
tar.c({
  sync: true,
  gzip: true,
  file: 'gh-274.tar.gz',
  cwd: 'gh-274',
}, require('fs').readdirSync('gh-274'))
JS

tar tvf gh-274.tar.gz

:<<OUTPUT
gh-274/
├── folder1
│   └── main.js
└── index.js

1 directory, 2 files
drwxr-xr-x  0 isaacs 20          0 Jul 28 10:15 folder1/
-rw-r--r--  0 isaacs 20          0 Jul 28 10:17 folder1/main.js
-rw-r--r--  0 isaacs 20          0 Jul 28 10:17 index.js
OUTPUT