This is a BBEdit text filter for indenting (and beautifying) JavaScript.

JavaScript Indent.js

#!/usr/local/bin/node

// PBS 12/5/13
// This is a BBEdit text filter for indenting (and beautifying) JavaScript.
// It goes in ~/Library/Application Support/BBEdit/Text Filters/
// 
// On my machine I assigned it a keyboard shortcut: cmd-'
// 
// It requires the js-beautify Node module: https://github.com/einars/js-beautify
// 
// The trick, in the script, was providing the full path to the globally-installed js-beautify module.
// 
// I figured out how to write a BBEdit/Node text filter from the very nice example here:
// http://www.mtaa.net/mtaaRR/news/twhid/geek/use_node_js_with_bbedit_text_filters_feature.html

var jsbeautify = require('/usr/local/lib/node_modules/js-beautify').js_beautify;

process.stdin.resume();
process.stdin.setEncoding('utf8');

process.stdin.on('data', function(chunk) {

  var s = jsbeautify(chunk, {
    indent_size: 2,
    brace_style: "end-expand"
  });

  process.stdout.write(s);
})

$ pip3 install jsbeautify
Defaulting to user installation because normal site-packages is not writeable
ERROR: Could not find a version that satisfies the requirement jsbeautify (from versions: none)
ERROR: No matching distribution found for jsbeautify

For what it's worth, I must have run into this, too, because I replaced this procedure with:

npm -g install js-beautify

... and everything seems to run fine.

This is the code for the BASH script I now use:

#!/bin/sh

## requires npm -g install js-beautify
## online at https://beautifier.io
## and https://github.com/beautify-web/js-beautify

## echo $BB_DOC_LANGUAGE

if [ "$BB_DOC_LANGUAGE" == "CSS" ]; then
    css-beautify
elif [ "$BB_DOC_LANGUAGE" == "HTML" ]; then
    js-beautify --html
elif [ "$BB_DOC_LANGUAGE" == "PHP in HTML" ]; then
    js-beautify --html
elif [ "$BB_DOC_LANGUAGE" == "JavaScript" ]; then
    js-beautify --jslint-happy
elif [ "$BB_DOC_LANGUAGE" == "JSON" ]; then
    python3 -m json.tool
else
    echo "unknown language: $BB_DOC_LANGUAGE"
fi