1487312 - No accessibility semantics for mutations inside shadow DOM

Status: RESOLVED FIXED

(Core :: Disability Access APIs, defect, P3)

Description

[James Teh [:Jamie]]

STR:
1. Open this test case:
data:text/html,<div id="host"></div><script>shadow = host.attachShadow({mode: 'open'}); setTimeout(function () { shadow.innerHTML = `<button>Go</button>`; }, 1000);</script>
2. Wait 1 second.
3. Look for the button in the Accessibility Inspector.
Expected: There should be a button with name "Go".
Actual: There is no button, only a text leaf.

It seems that the initial shadow tree gets populated correctly, but mutations do not.

Comment 1

[Emilio Cobos Álvarez (:emilio)]

Similar problems in the past have been fixes of this kind:

  GetParent() -> GetFlattenedTreeParent()
  IsInUnComposedDoc() -> IsInComposedDoc()

etc.

For this particular issue:

  https://searchfox.org/mozilla-central/rev/94e37e71ffbfd39e6ad73ebcda5d77cce8d341ae/accessible/generic/DocAccessible.cpp#1365

Looks wrong. aContainerNode is the ShadowRoot when we insert the <button>, you really want the host, which is aStartChildNode->GetFlattenedTreeParent().

Note that that code needs to deal with the flattened parent of the child nodes potentially being different (for example, for two different slots).

Also, looks like we don't create accessible stuff for display: contents, so you probably want to jump over those or something. Should be easy to test with a <slot>.

Comment 2

[Emilio Cobos Álvarez (:emilio)]

I can take a look at this, as long as somebody helps writing the tests :)

Comment 3

[Emilio Cobos Álvarez (:emilio)]

Attachment: Fix content insertion accessibility notifications in Shadow DOM.

The issue was specific to content insertion directly under a shadow root, the
rest should work (see bug 1427825 for the fix for other similar occurrences).

The removal of the aContainer argument follows the same pattern as bug 1442207.

Comment 4

[Emilio Cobos Álvarez (:emilio)]

Alex, review ping? I've added a test and such, I don't know if this fell off the radar or what not.

Comment 5

[alexander :surkov (:asurkov)]

(In reply to Emilio Cobos Álvarez (:emilio) from comment #4)
> Alex, review ping? I've added a test and such, I don't know if this fell off
> the radar or what not.

done, sorry for delay

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/011cfa1666cb
Fix content insertion accessibility notifications in Shadow DOM. r=Jamie,surkov

Comment 7

[Bogdan Tara[:bogdan_tara | bogdant]]

https://hg.mozilla.org/mozilla-central/rev/011cfa1666cb