387126 - Some MathML frames need to be eLineParticipant

Status: RESOLVED WORKSFORME

(Core :: MathML, defect)

Description

[Boris Zbarsky [:bzbarsky]]

STEPS TO REPRODUCE:

1) Load https://bugzilla.mozilla.org/attachment.cgi?id=268557
2) Get:

###!!! ASSERTION: Wrong line container hint: '!aForFrame || aLineContainer == FindLineContainer(aForFrame)', file ../../../mozilla/layout/generic/nsTextFrameThebes.cpp, line 1083

In this case, aLineContainer is an nsMathMLmtdInnerFrame (which sounds right if we want the block containing this thing), but FindLineContainer(aForFrame) gives nsMathMLTokenFrame, which is not surprising since that's not an eLineParticipant.  Nor is any other MathML frame.

Not sure which MathML frames are line participants, but it seems that nsMathMLTokenFrame is one for sure.

Comment 1

[Jesse Ruderman]

Bug 385265 is also about this assertion.

Comment 2

[Boris Zbarsky [:bzbarsky]]

Indeed.  I bet that patch fixes the issue I see here.  Will retest once it lands.

Comment 3

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

Are they really line participants?  If so, they have to call all the reflow functions on nsLineLayout appropriately, and ensure they create new line layout objects for any descendants that should be separated...

Comment 4

[Boris Zbarsky [:bzbarsky]]

Probably not, given the patch in bug 385265.

Comment 5

[Jesse Ruderman]

WFM.  bz, are you still seeing this?

Comment 6

[Boris Zbarsky [:bzbarsky]]

I have no idea.  I don't have a working tree to test with, and won't for several weeks.  Given that bug 385265 is fixed, this probably is as well.

Comment 7

[Frédéric Wang (:fredw)]

Apparently, there is no longer assertion message with current trunk build.