[0.8] Nested insertion points lose elements after distributeContent

[Sleeckx]

In the following scenario, Polymer.dom(this).children returns the <content> element.
Is this intended? If so, is going through the _distributedNodes property the correct way to get the real children or is there another api call I should be using?

http://jsbin.com/bixero/3/edit?html,output

[sorvell]

Yes, if I read the example correctly, this is intended behavior. Shady DOM and Shadow DOM share the same design. The distribution of nodes changes rendering but not dom structure. In this case the <content> element is a child of the <x-inner>. The children of <x-outer> get distributed such that they render in place of the insertion point where they get selected.

To see nodes distributed to an insertion point, Polymer.dom provides Polymer.dom(node).getDistributedNodes().

Fwiw, you can also see to which insertion point a given element has been distributed (generally this is not needed too much) using Polymer.dom(node).getDestinationInsertionPoints().

[Sleeckx]

Thanks Steve, this was exactly what I was looking for. I somehow overlooked this from the primer.

[Sleeckx]

The reason I bumped on the above question is for the following scenario where somehow the insertion point loses elements after distributeContent: http://jsbin.com/jejami/1/edit?html,output

Could this be related to this issue? #1394

[sorvell]

Definitely looks like a bug or 2 here. I'll investigate. Thanks for the detailed test case.

[Sleeckx]

Thanks, I also updated the sample case to reflect the latest changes.

[sorvell]

Currently, distributeContent is not smart enough to deal with redistribution. We'll fix it so it does.

In addition, we're planning on adding node mutation api (probably setAttribute and classList) to Polymer.dom so you should only rarely need to provoke distribution manually.

[sorvell]

Actually, you are right that the precise problem you noted is related to #1394. What I said is also true... fixes for both are on the way.

[Sleeckx]

Awesome, thanks!

Just to add some context to all of the above, this is the mock-up code of the real-world scenario we've build: http://jsbin.com/tireqatehe/1/edit?html

Adding the Polymer.dom API for adding/removing the attribute in this case and distributing immediately, will indeed eliminate the need to call distributeContent ourselves. Like you said.

[sorvell]

Fixed via d5070c5