Bug 173121 – Web Inspector: Web inspector does not show non-shadow children of an element with a shadow root (e.g. <video>)

• Status: RESOLVED
• Resolution: FIXED
• Component: Web Inspector

[Joseph Pecoraro]

Summary:
Web inspector does not show non-shadow children of an element with a shadow root (e.g. <video>)

Test:
<video controls>
    <source src="video.mp4" type="video/mp4">
</video>

Steps to Reproduce:
1. Inspect the <video>
2. Expand <video> to show children
  => Expected to see <source> only saw Shadow Root

[Joseph Pecoraro]

<rdar://problem/30948943>

[Joseph Pecoraro]

Created attachment 312373 [details]
[PATCH] Proposed Fix

[Joseph Pecoraro]

Comment on attachment 312373 [details]
[PATCH] Proposed Fix

View in context: https://bugs.webkit.org/attachment.cgi?id=312373&action=review

> Source/WebCore/inspector/InspectorDOMAgent.cpp:1370
> +        // Always send children if there are ShadowRoots since shadow and non-shadow children are bundled.

An alternative solution is to treat actual child nodes and shadow roots more discretely in the frontend. Currently they are all shared in _children and the existence of _children affects things. Switching to treating things more carefully the children can continue to be requested lazily. But this likely means a lot of places in the frontend will need to change based on how _children is used. I will look into this alternate solution and see how it compares to this current solution.

The approach in this patch could be problematic if the entire tree (or a very large portion) had nodes with shadow roots, but I don't think that is realistic.

[Joseph Pecoraro]

Comment on attachment 312373 [details]
[PATCH] Proposed Fix

View in context: https://bugs.webkit.org/attachment.cgi?id=312373&action=review

>> Source/WebCore/inspector/InspectorDOMAgent.cpp:1370
>> +        // Always send children if there are ShadowRoots since shadow and non-shadow children are bundled.
> 
> An alternative solution is to treat actual child nodes and shadow roots more discretely in the frontend. Currently they are all shared in _children and the existence of _children affects things. Switching to treating things more carefully the children can continue to be requested lazily. But this likely means a lot of places in the frontend will need to change based on how _children is used. I will look into this alternate solution and see how it compares to this current solution.
> 
> The approach in this patch could be problematic if the entire tree (or a very large portion) had nodes with shadow roots, but I don't think that is realistic.

I think the alternative approach will be simpler and better. I'm going to r- this.

[Joseph Pecoraro]

Created attachment 312486 [details]
[PATCH] Proposed Fix

[Matt Baker]

Comment on attachment 312486 [details]
[PATCH] Proposed Fix

r=me. Nice work avoiding a change to the backend.

[WebKit Commit Bot]

Comment on attachment 312486 [details]
[PATCH] Proposed Fix

Clearing flags on attachment: 312486

Committed r218020: <http://trac.webkit.org/changeset/218020>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.