2009643 - Refactor containing block size calculation in ReflowAbsoluteFrame()

Status: RESOLVED FIXED

(Core :: Layout: Positioned, task)

Description

[Ting-Yu Lin [:TYLin] (PST, UTC-7)]

Bug 1994346 introduces a logic in AbsoluteContainingBlock::Reflow() to compute cbSize for checking whether a first-in-flow needs to be pushed to the next fragmentainer. It currently uses:

const LogicalSize cbSize(containerWM, aContainingBlock.Size());

However, in AbsoluteContainingBlock::ReflowAbsoluteFrame() [1], there's a lambda that computes the containing block rect with various adjustments for anchor-positioning, grid container, and viewport frame. We should refactor the lambda in ReflowAbsoluteFrame() into a helper method and call it from both places to ensure consistent containing block size calculations. Or we could compute the containing block size in Reflow() and pass it into ReflowAbsoluteFrame().

[1] https://searchfox.org/firefox-main/rev/874c5779b2429acf0844c956bb72c529a2047b01/layout/generic/AbsoluteContainingBlock.cpp#1325-1405

Comment 1

[Ting-Yu Lin [:TYLin] (PST, UTC-7)]

The lambda that was previously in ReflowAbsoluteFrame() was extracted into ComputeContainingBlock() [1] by Bug 1991489, and we now store the unfragmented containing block and use it when needed [2].

At this point, I'm inclined to remove the comment at [3]. We can always file a targeted bug later if necessary.

[1] https://searchfox.org/firefox-main/rev/2d123ef3d530f3ae52f03978fbb9fe51af44bb5e/layout/generic/AbsoluteContainingBlock.cpp#502
[2] https://searchfox.org/firefox-main/rev/2d123ef3d530f3ae52f03978fbb9fe51af44bb5e/layout/generic/AbsoluteContainingBlock.cpp#614-631
[3] https://searchfox.org/firefox-main/rev/2d123ef3d530f3ae52f03978fbb9fe51af44bb5e/layout/generic/AbsoluteContainingBlock.cpp#741-742

Comment 2

[Ting-Yu Lin [:TYLin] (PST, UTC-7)]

Attachment: Bug 2009643 - Remove an obsolete comment in AbsoluteContainingBlock::Reflow(). r?#layout

See bug 2009643 comment 1 for the rationale for removing this comment.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/8c43740b57f6
https://hg.mozilla.org/integration/autoland/rev/8ae5e9269bce
Remove an obsolete comment in AbsoluteContainingBlock::Reflow(). r=layout-reviewers,dshin DONTBUILD

Comment 4

[rperta]

https://hg.mozilla.org/mozilla-central/rev/8ae5e9269bce