AllChildrenIterator misses native anonymous content from the root scroll frame

RESOLVED FIXED in Firefox 51

Status

()

Core
DOM
RESOLVED FIXED
a year ago
a year ago

People

(Reporter: bholley, Assigned: bholley)

Tracking

unspecified
mozilla51
Points:
---

Firefox Tracking Flags

(firefox51 fixed)

Details

Attachments

(2 attachments)

(Assignee)

Description

a year ago
It detects native anonymous children by QueryFrame-ing the primary frame to nsINativeAnonymousContentCreator. This generally works, but the root scroll frame is not the primary frame of the root element, and so we miss this case. This is problematic for stylo, since we restyle using the DOM rather than the frame tree, so we need our DOM iterator to handle corner cases like this.

I have a patch which I'll run through try.
(Assignee)

Comment 2

a year ago
Created attachment 8784472 [details] [diff] [review]
Handle the root scroll frame in AllChildrenIterator. v1
Attachment #8784472 - Flags: review?(cam)
Comment on attachment 8784472 [details] [diff] [review]
Handle the root scroll frame in AllChildrenIterator. v1

Review of attachment 8784472 [details] [diff] [review]:
-----------------------------------------------------------------

r=me with that fixed.

::: dom/base/ChildIterator.cpp
@@ +423,5 @@
> +        nsIPresShell* presShell = mOriginalContent->OwnerDoc()->GetShell();
> +        nsIFrame* scrollFrame = presShell ? presShell->GetRootScrollFrame() : nullptr;
> +        if (scrollFrame) {
> +          AppendAnonymousChildrenFromFrame(scrollFrame);
> +        }

Don't we need to do this all in GetPreviousChild too?
Attachment #8784472 - Flags: review?(cam) → review+
(Assignee)

Comment 4

a year ago
Created attachment 8785115 [details] [diff] [review]
Part 0 - Prevent HasPseudoElementData from erroneously tracking anonymous

boxes. r=heycam

The layout inspector ends up traversing into the root scroll frame in the next patch. If we don't
fix this, we erroneously enter this code here:

http://searchfox.org/mozilla-central/rev/44f6964ba95b8ddd8ebf70c55b34cd2323afeef4/layout/style/nsComputedDOMStyle.cpp#682

in this test:

devtools/client/inspector/markup/test/browser_markup_anonymous_04.js
Attachment #8785115 - Flags: review+

Comment 6

a year ago
Pushed by bholley@mozilla.com:
https://hg.mozilla.org/integration/mozilla-inbound/rev/e6a1ddda457e
Prevent HasPseudoElementData from erroneously tracking anonymous boxes. r=heycam
https://hg.mozilla.org/integration/mozilla-inbound/rev/6789cc1bb12a
Handle the root scroll frame in AllChildrenIterator. r=heycam
FWIW I just pushed a try run to check that we never have non-pseudo style inheriting from anon box style, except for the viewport scroll case, and I didn't get any failures.

https://treeherder.mozilla.org/#/jobs?repo=try&revision=f0d6f94673ac
(Assignee)

Comment 8

a year ago
Thanks! When I get around to it, I'll see if I can push a patch to try to make the root scroll NAC inherit null instead of the anon boxes.

Comment 9

a year ago
bugherder
https://hg.mozilla.org/mozilla-central/rev/e6a1ddda457e
https://hg.mozilla.org/mozilla-central/rev/6789cc1bb12a
Status: NEW → RESOLVED
Last Resolved: a year ago
status-firefox51: --- → fixed
Resolution: --- → FIXED
Target Milestone: --- → mozilla51
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