When HTML attribute is empty, binders receives 0 instead of undefined

[jccazeaux]

Issue

If binder is called like that

<div rv-my-binder></div>

Or

<div rv-my-binder=""></div>

It will receive 0 instead of null (or undefined ?)
See fiddle here : https://jsfiddle.net/jccazeaux/yqnubqkz/

Cause

The cause is in function parseType from parsers.coffee. In case of no HTML attribute we go into this case

else if (isNaN(Number(string)) === false) {
  value = Number(string)
}

because

     Number(null) == Number("") == 0

I think binder should receive undefined when HTML attribute is empty or not specified. If you agree i'll send the PR

[Duder-onomy]

👍 Agreed. We all know 0 will be coerced into a false but having it pass undefined is semantically correct.

My only issue, take the required attribute on the input tag for example. If the attribute is present, that is enough to warrant a true value. It does not have to be explicitly set as required='true'.
But..... That is weird anyways.

Thoughts?

[jccazeaux]

As you say it's weird, but it's still possible. The binder's code would have to consider undefined as true.

[Duder-onomy]

I am all for this. It is a minor but important improvement.

I will attach it to the 0.9 release. If anyone has any objections, please chime in.

@jccazeaux Will you champion this one for us?

[Duder-onomy]

Closing.