convert es5 js to es2015 using lebab and prettier

5to6.js

// requires node > 8
const lebab = require('lebab')
const prettier = require('prettier')
const util = require('util')
const readFile = util.promisify(require('fs').readFile)

;(async () => {
  try {
    const input = process.argv.slice(2)[0]
    const body = await readFile(input, 'utf8')

    const { code, warnings } = lebab.transform(body, [
      'arrow',
      'for-of',
      'arg-spread',
      'obj-method',
      'obj-shorthand',
      'no-strict',
      'commonjs',
      'exponent',
      'multi-var',
      'let',
      'class',
      'template',
      'default-param',
      'includes'
    ])

    const prettied = prettier.format(code, {
      semi: false,
      singleQuote: true
    })

    console.log(prettied)
  } catch (e) {
    console.error('e:', e)
  }
})()