$ git clone https://github.com/jlongster/jscodefmt.git
$ cd jscodefmt
$ npm install -g .
$ jscodefmt file.js

It's most useful when integrated with your editor, so see editors to for editor support. Currently only Emacs integration exists.

To integrate in Emacs, add the following code. This will format the file when saved.

(require 'jscodefmt)
(add-hook 'js-mode-hook
          (lambda ()
            (add-hook 'before-save-hook 'jscodefmt-before-save)))