string/length behavior change in 0.41.0

[apellerano-pw]

In 0.41.0 string/length was changed from using normalizeString to normalizeString2 and this is causing some of my previously working code (0.40.0 and earlier) to fail.

(Here's the change commit I believe is the culprit 9d37d08#diff-e79df0685b1844367badb5763902f884L3)

Repro case

If you have something in your component js like

import Component from '@ember/component';
import length from 'ember-awesome-macros/string/length';
export default Component.extend({
  myStr: null,
  crashTime: length('myStr'),
});

and a template of

{{crashTime}}

Then ember-awesome-macros will throw an error in normalizeString2 during

let prop = stringVal[func];

because stringVal is null.

The old behavior, with normalizeString, was this

if (!val) {
  return val;
}

which would early return the null value before the function trys to evaluate func.

I'm not sure what the intended behavior for your addon is so I don't know if this is a bug on my end or a regression on yours; what do you think? The question could be boiled down to, what should the string/length macro do in the case of null value strings?