find api do not unique child node

[douzi8]

<ul>
  <li>
    <ul>
      <li>
    </ul>
  <li>
    <ul>
      <li>
    </ul>
</ul>

$('ul li').length  
$('ul').find('li').length

// Two length is not equal

[jansesun]

I verified the case above, indeedly the two equivalent expressions have different values in Zepto rather than in jQuery.

[mislav]

Should we filter the results of every such query to ensure that no Zepto collection ever contains the same DOM node more than once?

Similar find() problem when compared to jQuery, but with different causes: https://github.com/madrobby/zepto/issues/730