$.fn.filter fails when the collection includes the document

[johnbender]

An example from snapper:

https://github.com/filamentgroup/snapper/blob/master/src/snapper.js#L292

$( document ).bind( "enhance", function( e ){
  $( "." + pluginName, e.target ).add( e.target ).filter( "." + pluginName )[ pluginName ]();
});

The e.target in this case is the document. An exception occurs here:

https://github.com/filamentgroup/shoestring/blob/master/src/dom/filter.js#L27

Where it attempts to append the document to the document fragment and the browser throws an exception.