Add a cell border specificity comparator which preserves the winning
border logic according to specification and makes it possible to sort
borders by specificity. This will be important for handling the style of
table cell corners in a way consistent with other browsers.
Computing the table width algorithm bifurcates based on whether
table-root width is auto. We only adjust the used table width based on
cell percentage widths on the auto branch, thus the same check is needed
when we initialize cell widths.
Cell percentage widths are relative to table width, not containing
block width. If the table width is auto, there isn't a normative
specification, only a brief mention that the user agent should try to
meet it.
As a starting point, we increase the width of the table such that it's
sufficient to cover min-width of cells with a percentage width. This
matches the behavior of other browsers, at least for simple cases.
This ensures that min-content contributions from cells with no content
are computed using their calculated values, which are never considered
for min-content before then. The specification diverges from column
measures algorithm, which doesn't use specified width of cells anywhere.
The used width is already a content width, which doesn't include
borders. Border widths should be subtracted from the specified width
instead, since that initially specifies the total width including
borders, for consistent comparison. Also handle table box padding as an
additional fix.
Adding undistributable space right before setting the content width is
incorrect when it's a percentage. Follow the specification and add it to
GRIDMIN and GRIDMAX instead.
The shortcut we put in place didn't resolve percentage widths and
ignored border spacing. We can still return early after we compute the
width per the specifications.
Compute the contributions to a spanning cell width from each cell in the
span. This better handles uneven column widths, since each cell
contribution is proportional with its own width as opposed to the own
width of the first cell in the span.
This better matches the behavior of other browsers and further aligns
with the specification.
When resolving a percentage min-width or min-height size against a
containing block currently under a min-content constraint, we should act
as if the containing block has zero size in that axis.
This is technically "undefined behavior" per CSS 2.2, but it seems
sensible to mirror the behavior of max-height in the same situation.
It also appears to match how other engines behave.
Fixes#19242
Although DistinctNumeric, which is supposed to abstract the underlying
type, was used to represent CSSPixels, we have a whole bunch of places
in the layout code that assume CSSPixels::value() returns a
floating-point type. This assumption makes it difficult to replace the
underlying type in CSSPixels with a non-floating type.
To make it easier to transition CSSPixels to fixed-point math, one step
we can take is to prevent access to the underlying type using value()
and instead use explicit conversions with the to_float(), to_double(),
and to_int() methods.
Add logic to compute {min, max}-height and use min-height when
calculating table height, per specifications.
Fixes some issues with phylogenetic tree visualizations on Wikipedia.
The specification isn't explicit about it, but the contribution we
compute should be distributed to all columns, not just the first one.
The first reason for it is symmetry, it doesn't make sense for the
increased width of the spanning column to only affect the first column
in the span.
The second reason is the formula for the cell contribution, which is
weighted by the non-spanning width of the cell relative to the total
width of the columns in the same row. This only covers a fraction of the
gap, in order to fully cover it we have to add it to all columns in the
span. For this to be exactly the case when the columns don't all have
the same width, we'd have to add additional weighting based on the width
ratios, but given that the specification doesn't suggest it at all we'll
leave it out for now.
These are only used during layout, and always within formatting context
code, so we might as well put them in FormattingContext and avoid having
to pass the LayoutState around all the time.
Solves conflict in layout tree "type system" when elements <label> (or
<button>) can't have `display: table` because Box can't be
Layout::Label (or Layout::ButtonBox) and Layout::TableBox at the same
time.
This commit implements following missing steps in table layout:
- Calculate final table height
- Resolve percentage height of cells and rows using final table height
- Distribute avilable height to table rows
If total max columns width (grid_max) is zero then available width
should be divided equally between columns. Previously there was
division by zero: `column.max_width / grid_max`.
Previously, the minimum height of a table row was calculated based
on the automatic height of the cells inner layout. This change makes
computed height of a cell boxes also be considered if it has definite
value.
Instead of special-casing FlexFormattingContext in the intrinsic sizing
layout helpers, add FormattingContext::automatic_content_width() and let
each context subclass decide what that means.
No behavior change here, just moving this responsibility.
Change `compute_auto_height_for_block_level_element` to use max height
(`m_automatic_content_height` produced from TFC) for tables with auto
height which is more correct behaviour than treating them like block
containers.
