es6-update
This is a quick (and dirty) way to clean up most migration issues from es5 code to es6+ code.
WARNING: The dirty... This will not clean up all feasable combinations of useless returns. It may leave hanging chads in the form of not deleting closing parens.
Install
npm i -g es6-upgrade
Usage
es6-upgrade <filename> # or es6up es6up --help # To preview output es6up -p <filename>