918994 - "ASSERTION: Can't sticky position individual continuations" with rtl, wrapping

Status: RESOLVED FIXED

(Core :: Layout: Positioned, defect)

Description

[Jesse Ruderman]

Attachment: testcase

###!!! ASSERTION: Can't sticky position individual continuations: '!aFrame->GetPrevContinuation()', file layout/generic/StickyScrollContainer.cpp, line 133

Comment 1

[Corey Ford [:coyotebush]]

Attachment: layer tree and stack

We're reaching this via StickyScrollContainer::ComputeScrollRanges (from bug 897105).

I guess I hadn't considered how those two should interact. Ideally, I suppose we only need one layer per sticky element, not per sticky frame. But even with a layer per frame, the ScrollRanges are relative, so should be identical for each frame's layer. So we might be able to just move that assertion from ComputeStickyLimits into ComputePosition?

Comment 2

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

But it's computing incorrect results because GetAllInFlowRectsUnion actually only looks forward and not backward.

I'll probably fix this in bug 828312 patch 9a, though.

Comment 3

[Jesse Ruderman]

This testcase no longer asserts on mozilla-central.  I guess it was fixed in bug 828312.