feat(isNaN): isNumberNaN

[PatrickJS]

window.isNaN(‘lol’); //=> true
Number.isNaN(‘lol’); //=> false

isNaN converts it’s arguments into a Number before checking if it’s NaN. Number.isNaN fixes this but we can also polyfill it

[pkozlowski-opensource]

@gdi2290 is there any reason to polyfill this particular ES6 method inside the core? Shouldn't we rather advice people to include a full / partial polyfill if they need it?

[PatrickJS]

well I didn't keep this global on the angular object so it's for internal use since it's inside of the closure. Throughout the code base the team is checking if it is a number before running isNaN. Adding this would save a few lines and from this js gotcha

if (isNumber(ctrl.$modelValue) && isNaN(ctrl.$modelValue)) {
// would be
if (isNaN(ctrl.$modelValue) {
//
minVal = isNumber(val) && !isNaN(val) ? val : undefined;
// would be
minVal = !isNaN(val) ? val : undefined;

[pkozlowski-opensource]

@gdi2290 so, if you believe that the changed isNaN version can be used to improve existing code, could you please include those changes in this PR?

[PatrickJS]

I think would be better if I name it isNumberNaN and replace all isNaN to isNumberNaN I'll update the PR

[jbedard]

and instead of defining a function that wraps both the Number.isNaN and pollyfill it should only provide a pollyfill in place of Number.isNaN. Something such as...

var isNumberNaN = Number.isNaN || function(n) {
   ...
};

[PatrickJS]

good idea

var _isNaN = window.isNaN;
var isNumberNaN = Number.isNaN || function isNumberNaN(num) {
  return isNumber(num) ? _isNaN(num) : false;
};

[realityking]

Nice idea.

Number.isNaN can be more easily (and a bit faster) polyfilled like this

function isNumberNaN(value) {
  return value !== value;
}

[jbedard]

I don't think this one should change. This one specifically wanted "123" to pass...