* layout: Implement support for `line-height` and `vertical-align`
This is an initial implementation of proper `line-height` and
`vertical-align` support. While this change includes the bulk of the
work there are still many missing pieces for full support. In particular
some big missing things are:
- Flex containers do not properly compute their baselines. The idea is
to tackle this in a followup change. This causes various flex tests
to start failing because everything used to be top aligned.
- The implementation of the line-height quirks (only active in quirks
mode) are incomplete. While the quirk works in many cases, there are
still some cases where it is handled incorrectly. This requires more
redesign and refinement, better suited for a followup.
- Most of the features are CSS 3 such as precision control of the
baseline and first and last baselines are not implemented. This
change gets us close to CSS 2.x support.
While there are many new test passes with this change some tests are
starting to fail. An accounting of new failures:
Tests failing also in Layout 2013:
- /css/css2/positioning/toogle-abspos-on-relpos-inline-child.html (only passes in Chrome)
- /css/CSS2/fonts/font-applies-to-001.xht (potentially an issue with font size)
Invalid tests:
- /css/CSS2/visudet/inline-block-baseline-003.xht
- /css/CSS2/visudet/inline-block-baseline-004.xht
- These are are failing in all browsers. See https://bugs.chromium.org/p/chromium/issues/detail?id=1222151.
Missing table support:
- /_mozilla/mozilla/table_valign_middle.html
Missing `font-size-adjust` support :
- /css/css-fonts/font-size-adjust-zero-2.html (also failing in 2013)
Incomplete form field support :
- /html/rendering/widgets/the-select-element/option-add-label-quirks.html (label isn't rendered so button isn't the right size in quirks mode due to line height quirk)
Need support for calculating flexbox baseline:
- /css/css-flexbox/fieldset-baseline-alignment.html
- /css/css-flexbox/flex-inline.html
- /css/css-flexbox/flexbox-baseline-multi-line-horiz-001.html
- /css/css-flexbox/flexbox-baseline-single-item-001a.html
- /css/css-flexbox/flexbox-baseline-single-item-001b.html
Failing because we don't create anonymous inline boxes for text children of blocks:
- /css/CSS2/linebox/anonymous-inline-inherit-001.html
Passes locally (potentially related to fonts):
- /css/CSS2/css1/c414-flt-fit-004.xht
- /css/css-transforms/transform-input-017.html
- /html/obsolete/requirements-for-implementations/the-marquee-element-0/marquee-min-intrinsic-size.html
- /css/css-fonts/first-available-font-005.html
- /css/css-fonts/first-available-font-006.html
* Some cleanups after live review with @mukilan
Also update results.
Improve the calculation of the block size of line boxes and all their
component elements. Even empty spans can increase the size of the line
based on their font-size. Elements that have a line-height should
increase the block size of the line, but that setting should not effect
their own size.
In addition to the new passes there are some new failures
Failing because a progression exposes the real issue these tests are
testing:
- css/css-color/t32-opacity-offscreen-multiple-boxes-1-c.xht
- css/css-color/t32-opacity-offscreen-multiple-boxes-2-c.xht
Likely failing because of vertical-align and another sizing issue:
- css/css-transforms/perspective-untransformable-no-stacking-context.html
Failing because a progression reveals another failure:
- html/rendering/non-replaced-elements/hidden-elements.html
Co-authored-by: Mukilan Thiyagarajan <mukilan@igalia.com>
When a box has overflow, any floats placed in that box will lower the
float ceiling into the overflow. If no float is placed in the box
though, the ceiling should be the block position where the overflow
starts. We already know where this is, because we might be passing a
negative value for the new block position after processing a box
(content_size - actual_size would be negative). This negative value
never raises the ceiling though since a maximum is used.
In the case that there is overflow, this change allows raising the
ceiling, but never passed the lowest float. This necessitates keeping
two values for the ceiling: one for floats and one for non-floats.
Fixes#30304.
layout_2020: Do linebreak for atomic inline-level elements
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