This patch implements "Overflow Viewport Propagation" from CSS-OVERFLOW.
It fixes an issue where many websites were not scrollable because they
had `overflow: scroll` on the body element and we didn't propagate it.
Pseudo-elements like ::before and ::after were discarded when their
content property was an empty string (ignoring whitespace), because they
are anonymous containers with no lines.
Our previous way around it was to add an empty line box (see b062a0fb7c)
however it didn't actually work for cases described in the previous
commit.
This makes avatars and cover arts square on last.fm and "fixes" the test
css-pseudo-element-should-not-be-affected-by-presentational-hints.html.
Unfortunately, this also regresses on block-and-inline/clearfix.html,
but that hopefully will be handled in subsequent commit.
Properties like min-width, max-width, etc, should be ignored while we're
trying to determine the intrinsic size of a flex container.
This fixes an infinite recursion when using an intrinsic size keyword as
the max-width of a flex column container.
Note that this behavior is marked as AD-HOC in code comments because
specs don't tell us how to achieve intrinsic sizing.
We can now load product pages on the Twinings site, such as
https://twinings.co.uk/products/earl-grey-100-tea-bags :^)
Fixes the issue that before "automatic minimum size" were used to size
flexible tracks even though specification says is should be "minimum
contribution"
Previously, we always rounded border-widths up when converting them to
device pixels. However, the spec asks us to follow a specific algorithm
to "snap" these values, so that the computed value is snapped.
The difference from before, is that widths of between 0 and 1 device
pixels are rounded up to 1, and and values larger than 1 are rounded
down.
If a math function resolves to `<length>` or `<percentage>`, then it
will by definition also resolve to `<length-percentage>`. (Same for any
other basic types.) Since we were checking `<length-percentage>` first
and then bailing if no given properties could accept that, math
functions would always fail to match a property that just accepts a non
`-percentage` type.
This is a universal value like `initial` and `inherit` and works by
reverting the current value to whatever we had at the start of the
current cascade origin.
The implementation is somewhat inefficient as we make a copy of all
current values at the start of each origin. I'm sure we can come up with
a way to make this faster eventually.
Allow the left margin of a box which creates a block formatting context
to overlap with left floating boxes which are siblings in the document
tree.
Fixes#20233 and the comment layout on https://lobste.rs.
This change makes tree builder omit elements with "display: contents"
from the layout tree during construction. Their child elements are
instead directly appended to the parent element in layout tree.
For malformed tables which only have cells with span greater than 1, the
content sizes for row and column aren't initialized to non-zero values.
Avoid undefined behavior in such cases, which sometimes show up on
Wikipedia.
Auto margins used together with justify-content would previously
result in children being positioned outside their parent. This was
solved by letting auto margins take precedence when they are used,
which was already implemented to some extent before, but not
fully.
After switching to fixed-point arithmetic in CSSPixels, it no longer
supports representing infinite values, which was previously the case
for remaining_free_space in FFC. Using Optional that is not empty only
when value is finite to store remaining_free_space ensures that
infinity is avoided in layout calculations.
Before this change, we always derived a box's baseline from its last
child, even if the last child didn't have any line boxes inside.
This caused baselines to slip further down vertically than expected.
There are more baseline alignment issues to fix, but this one was
responsible for a fair chunk of trouble. :^)
Follow the computing column measures section of the specification, which
gives an algorithm for setting intrinsic percentage widths when spanning
columns are involved.
Change how we store type of columns. It was used where the specification
only distinguishes between percent and everything else, so it makes more
sense to store and use it as a boolean.
The specification says we should distribute excess width proportionally
to the width of the cell, not to the preferred increment. Doing the
latter leads to distributing all excess width to just the cells which
demand some increment, even if it's very modest. Moreover, there's code
which partially implements the correct criteria just below the one we
remove here.
Once we've resolved the used flex item width & height, we should allow
percentage flex item sizes to resolve against them instead of forcing
flex items to always treat percentages as auto while doing intrinsic
sizing layout.
Regressed in 8dd489da61.
We do this by piggybacking on FormattingContext helpers instead of
reinventing the wheel in FlexFormattingContext.
This fixes an issue where `min-width: fit-content` (and other
layout-dependent values) were treated as 0 on flex items.
This makes the cookie banners look okay on https://microsoft.com/ :^)
If an inline-block has a percentage height that relies on the auto
height of the containing block, it should always resolve to the
automatic height of the box, regardless of the percentage value. This
change may seem confusing, but it aligns with the behavior of other
engines.
There are two parts to this fix:
- First, StyleProperties::transformations() would previously omit calc()
values entirely when returning the list of transformations. This was
very confusing to StackingContext which then tried to index into the
list based on faulty assumptions. Fix this by emitting calc values.
- Second, StackingContext::get_transformation_matrix() now always calls
resolve() on length-percentages. This takes care of actually resolving
calc() values. If no reference value for percentages is provided, we
default to 0px.
This stops LibWeb from asserting on websites with calc() in transform
values, such as https://qt.io/ :^)
This change implements following paragraph from placement algorithm in
the spec:
"If the largest column span among all the items without a definite
column position is larger than the width of the implicit grid, add
columns to the end of the implicit grid to accommodate that column
span."
There were places in the grid implementation code with copies of this
text, but those were completely unrelated to the code where they were
being pasted so I removed them.
Max width shouldn't be tied to min width, commit d33b99d went too far
and made them the same when the table-root had a specified percentage
width.
Fixes#19940.