Is there a RegExp.escape function in JavaScript?

There is an ES7 proposal for RegExp.escape at https://github.com/benjamingr/RexExp.escape/, with a polyfill available at https://github.com/ljharb/regexp.escape.

An example based on the rejected ES proposal, includes checks if the property already exists, in the case that TC39 backtracks on their decision.

Code:

if (!Object.prototype.hasOwnProperty.call(RegExp, 'escape')) {
  RegExp.escape = function(string) {
    // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions#Escaping
    // https://github.com/benjamingr/RegExp.escape/issues/37
    return string.replace(/[.*+\-?^${}()|[\]\\]/g, '\\$&'); // $& means the whole matched string
  };
}

Code Minified:

Object.prototype.hasOwnProperty.call(RegExp,"escape")||(RegExp.escape=function(e){return e.replace(/[.*+\-?^${}()|[\]\\]/g,"\\$&")});

// ...
var assert = require('assert');
 
var str = 'hello. how are you?';
var regex = new RegExp(RegExp.escape(str), 'g');
assert.equal(String(regex), '/hello\. how are you\?/g');

There is also an npm module at:
https://www.npmjs.com/package/regexp.escape

One can install this and use it as so:

npm install regexp.escape

or

yarn add regexp.escape

var escape = require('regexp.escape');
var assert = require('assert');
 
var str = 'hello. how are you?';
var regex = new RegExp(escape(str), 'g');
assert.equal(String(regex), '/hello\. how are you\?/g');

In the GitHub && NPM page are descriptions of how to use the shim/polyfill for this option, as well. That logic is based on return RegExp.escape || implementation;, where implementation contains the regexp used above.

The NPM module is an extra dependency, but it also make it easier for an external contributor to identify logical parts added to the code. ¯\(ツ)/¯