Delegate something that isn't provided

[mrego]

This is a separated issue extracted from #7.

What should happen if you delegate something and it isn't provided? Could it be provided implicitly somehow?

Example:

<x-foo>
  <template shadowroot="closed" shadowrootdelegatesariaattributes="aria-label">
    <input id="input" delegatedariaattributes="aria-label" />
  </template>
</x-foo>

[nolanlawson]

What do you mean by "provided implicitly"? Does this overlap with ElementInternals?

[mrego]

Probably @bkardell can clarify, as this is a question from him in the original issue.

[bkardell]

Yeah, I just meant that you could have something like

<label for="x">Favorite Quote</label>
<rich-text id="x">
   (ShadowRoot)
      (Some stuff)
      (The actual area that should have a label)
</rich-text>

and if you are literally just delegating attributes down the tree that doesn't help all of the native built-in roles/relationships I guess?

[nolanlawson]

Is this the same as reflection/exporting? In your example, the for IDref is pointing down into the shadow root. (As opposed to delegation/importing, where it points out of a shadow root.)

Also related: #13 (since for is not technically ARIA).

[keithamus]

WCCG had their spring F2F in which this was discussed. You can read the full notes of the discussion (WICG/webcomponents#978 (comment)) in which this was discussed, heading entitled "ARIA Mixin & Cross Root ARIA" - where this issue was specifically discussed.

In the meeting, present members of WCCG reached a consensus to discuss further in breakout sessions. I'd like to call out that WICG/webcomponents#1005 is the tracking issue for that breakout, in which this will likely be discussed.