$.attr() handles boolean properties wrongly

[PhilippMi]

$el.attr({checked: true}) results in the following html <input checked="true"> which is not allowed in HTML5.

jquery handles this case correctly. jquery: https://codepen.io/phmitterer/pen/QvBXgE?editors=1111 zepto: https://codepen.io/phmitterer/pen/KmBjmN?editors=1111

[hkongm]

use the prop()

[madrobby]

It would probably be good to handle this the same way as jQuery does.

[chris-oreilly]

I'm working on a PR for this issue. But instead of doing it like jQuery, which results in <input checked="checked">, I think it ought to be <input checked>. The first form is "non-standard" according to MDN. This wouldn't break compatibility as long as we return the correct value from $('input').attr('checked'). Thoughts?