node.append et al. does not work when node is a DocumentFragment

[joeyadams]

The following does not work as expected:

jQuery(document).ready(function($) {
    var frag = $(document.createDocumentFragment());
    var h3   = $('<h3>It works</h3>');
    frag.append(h3); // Should append h3 to the DocumentFragment, but doesn't
    $(document.body).append(frag);
});

Namely, when a jQuery object selects a DocumentFragment, .append doesn't append to it. This is because of how the nodeType is tested:

	append: function() {
		return this.domManip(arguments, true, function( elem ) {
			if ( this.nodeType === 1 ) {
				this.appendChild( elem );
			}
		});
	},

A DocumentFragment has a different nodeType than an HTML element, which the implementation of append omits.

Unfortunately, this isn't an isolated issue. The nodeType === 1 test appears all over the jQuery source. The general fix would involve adding || nodeType === 11 in those places, but only when applicable.

DocumentFragment can be used to add many DOM nodes to a page more efficiently. See  John Resig's blog post about DocumentFragment for more info.

[dmethvin]

As you've pointed out, there is a lot of work involved in trying to make this work. It's not documented to work, somewhat similar to the queasy relationship a jQuery collection has with text or comment nodes. What are the benefits of trying to expand documentFragment to first-class citizenship? What problems become easy to solve that aren't currently easy? If it's an important issue, why has it taken five years for someone to report this?

[trac-o-bot]

Because we get so many tickets, we often need to return them to the initial reporter for more information. If that person does not reply within 14 days, the ticket will automatically be closed, and that has happened in this case. If you still are interested in pursuing this issue, feel free to add a comment with the requested information and we will be happy to reopen the ticket if it is still valid. Thanks!

[Vladimir Zhuravlev]

Fix #11566, allow appending to DocumentFragment, closes gh-814.

Changeset: 9c28a320c3fa6dcc06de4919d24da41451843570