don't change string prototype

[dylang]

if (typeof String.prototype.startsWith !== "function") {
  String.prototype.startsWith = function (str) {
    return this.slice(0, str.length) === str;
  };
}

This means you are changing how string works for all code that depends on your code.

It would be prefered to use a function or something like underscore.string. https://github.com/epeli/underscore.string

I'm not sure if this is related, but a co-worker is seeing this:

depcheck/index.js:95
      if (usedDependency === definedDependency || usedDependency.startsWith(de
                                                                 ^
TypeError: Object 11 has no method 'startsWith'
    at node_modules/npm-check/node_modules/depcheck/index.js:95:66

[rumpl]

The error your co-worker is having is odd...

What do you think about this polyfill ?

[dylang]

That's a good find, but I'm still not a fan of changing the prototype.

If you look at his code, the first line is

if (!String.prototype.startsWith) {

This means that if any other node module changes the prototype by adding a startsWith before yours runs, your code will be using that other code instead of that polyfill.

It just feels too risky to me to rely on.

[rumpl]

Fair enough.

Will change it to a normal function.