safe-regex2
detect potentially
catastrophic
exponential-time
regular expressions by limiting the
star height to 1
This is a fork of https://github.com/substack/safe-regex at 1.1.0.
WARNING: This module has both false positives and false negatives.
It is not meant as a full checker, but it detect basic cases.
example
var safe = require('safe-regex2');
var regex = process.argv.slice(2).join(' ');
console.log(safe(regex));
$ node safe.js '(x+x+)+y'
false
$ node safe.js '(beep|boop)*'
true
$ node safe.js '(a+){10}'
false
$ node safe.js '\blocation\s*:[^:\n]+\b(Oakland|San Francisco)\b'
true
methods
var safe = require('safe-regex')
var ok = safe(re, opts={})
Return a boolean ok
whether or not the regex re
is safe and not possibly
catastrophic.
re
can be a RegExp
object or just a string.
If the re
is a string and is an invalid regex, returns false
.
opts.limit
- maximum number of allowed repetitions in the entire regex.
Default: 25
.
install
With npm do:
npm install safe-regex2
license
MIT