Rule to sort properties in object literal

Similar to sort-vars, how about a rule to always sort object properties alphabetically when defining an object literal?

It would be really useful for things like options objects. I realize that the property order can matter in iteration, but it’s nothing you should rely on anyway. With the new ES6 data structures, I think the use case for object literals is shrinking to be a lot about options objects, including in native APIs.

You could argue that it will cause a huge number of warnings in existing code and thus not be useful at all. I’m not completely sure, I just know that I often use vim’s sort command, but it doesn’t work well if a property value spans several lines.

Warnings:

var obj = {
  c: "foo",
  a: "bar",
  b: {
    e: 1,
    d: 2,
  }
};

OK:

var obj = {
  a: "bar",
  b: {
    d: 2,
    e: 1,
  },
  c: "foo",
};

[Gopikrishna19]

http://eslint.org/docs/rules/sort-keys from eslint 3.3.0 on 😃

[gajus]

@nzakas Now that https://github.com/jacobrask/eslint-plugin-sorting has somewhat matured, is it worth it to consider adding it to the core?