escape-string-regexp 
Escape RegExp special characters
Install
$ npm install escape-string-regexp
Usage
const escapeStringRegexp = require('escape-string-regexp');
const escapedString = escapeStringRegexp('How much $ for a 🦄?');
//=> 'How much \\$ for a 🦄\\?'
new RegExp(escapedString);
You can also use this to escape a string that is inserted into the middle of a regex, for example, into a character class.
License
MIT © Sindre Sorhus