REY Sébastien - 2016-03-22

Better than beautifier.js
Decode strings
un-minimize
it use JSTools/JSFormat to un-minimize

import re
import codecs

ESCAPE_SEQUENCE_RE = re.compile(r'''
    ( \\U........      # 8-digit hex escapes
    | \\u....          # 4-digit hex escapes
    | \\x..            # 2-digit hex escapes
    | \\[0-7]{1,3}     # Octal escapes
    | \\N\{[^}]+\}     # Unicode characters by name
    | \\[\\'"abfnrtv]  # Single-character escapes
    )''', re.UNICODE | re.VERBOSE)

def decode_escapes(s):
    def decode_match(match):
        return codecs.decode(match.group(0), 'unicode-escape')

    return ESCAPE_SEQUENCE_RE.sub(decode_match, s)

donnees = editor.getText()
strings=re.finditer("(\".+\")",donnees)
for s in strings:
    editor.replace(s.group(0)[1:-1],decode_escapes(s.group(0)[1:-1]))
notepad.runMenuCommand("JSTool", "JSFormat")