If box is sized as replaced it still could be anything, not only SVG.
This fixes crashing on https://www.shopify.com/ that was caused by a
missing paintable for a box that has a layout node. This occurred
because the box was not laid out in dimension_box_on_line().
...because "change" event should be dispatched on control even if it
has "display: none" style.
This change fixes selection in labels dropdown on GitHub's "new issue"
page.
Given a selector like `.foo .bar #baz`, we know that elements with
the class names `foo` and `bar` must be present in the ancestor chain of
the candidate element, or the selector cannot match.
By keeping track of the current ancestor chain during style computation,
and which strings are used in tag names and attribute names, we can do
a quick check before evaluating the selector itself, to see if all the
required ancestors are present.
The way this works:
1. CSS::Selector now has a cache of up to 8 strings that must be present
in the ancestor chain of a matching element. Note that we actually
store string *hashes*, not the strings themselves.
2. When Document performs a recursive style update, we now push and pop
elements to the ancestor chain stack as they are entered and exited.
3. When entering/exiting an ancestor, StyleComputer collects all the
relevant string hashes from that ancestor element and updates a
counting bloom filter.
4. Before evaluating a selector, we first check if any of the hashes
required by the selector are definitely missing from the ancestor
filter. If so, it cannot be a match, and we reject it immediately.
5. Otherwise, we carry on and evaluate the selector as usual.
I originally tried doing this with a HashMap, but we ended up losing
a huge chunk of the time saved to HashMap instead. As it turns out,
a simple counting bloom filter is way better at handling this.
The cost is a flat 8KB per StyleComputer, and since it's a bloom filter,
false positives are a thing.
This is extremely efficient, and allows us to quickly reject the
majority of selectors on many huge websites.
Some example rejection rates:
- https://amazon.com: 77%
- https://github.com/SerenityOS/serenity: 61%
- https://nytimes.com: 57%
- https://store.steampowered.com: 55%
- https://en.wikipedia.org: 45%
- https://youtube.com: 32%
- https://shopify.com: 25%
This also yields a chunky 37% speedup on StyleBench. :^)
I've seen a crash when trying to verify_cast some block-level box to a
BlockContainer when it's actually something else.
This patch adds a debug log message so we can learn more about it next
time it happens somewhere.
There is no need to run full table layout if we are only interested in
calculating its width.
This change reduces compute_table_box_width_inside_table_wrapper()
from ~30% to ~15% in profiles of "File changed" pages on github.
Instead of TextPaintable fragments being an offset+length view into the
layout node, they are now a view into the paintable instead.
This removes an awkward time window where we'd have bogus state in text
fragments after layout invalidation but before relayout. It also makes
the code slightly nicer in general, since there's less mixing of layout
and painting concepts.
Before this change, we were not detaching paintables from DOM nodes
within shadow subtrees.
This appears to be the main reason that keyboard editing was doing
immediate forced relayout: doing a full layout invalidation meant we'd
build a new layout tree, which then hid the problem with with
still-attached paintables.
By detaching them before committing a new layout, we make it possible
for keyboard editing to just use normal relayout, instead of full forced
invalidation & relayout.
Rather than try to lay out masks normally, this updates the TreeBuilder
to create layout nodes for masks as a child of their user (i.e. the
masked element). This allows each use of a mask to be laid out
differently, which makes supporting `maskContentUnits=objectBoundingBox`
fairly easy.
The `SVGFormattingContext` is then updated to lay out masks last (as
their sizing may depend on their parent), and treats them like
viewports.
This is pretty ad-hoc, but the SVG specification does not give any
guidance on how to actually implement this.
This patch also makes FlexFormattingContext::calculate_static_position
use computed values for margins and borders, since this function may be
called before the box's state has been finalized.
When placement position is found we always want to do following:
- Mark the occupied cells in the occupation grid
- Add the item to the list of placed items
Therefore, having helper that does both is useful
With this change we use the same code to resolve (start, end, span)
based on computed values in all cases:
- When only column is definite
- When only row is definite
- When both are definite
Moves the code that identifies (start, end, span) for a grid item into
a separate function. By doing so, we can eliminate the duplicated code
between the placement of grid items with definite columns and those
with definite rows.
This change omits some of the comments that reference the spec, as they
were largely irrelevant and unhelpful for making changes or diagnosing
issues.
Table wrappers don't quite behave the same as most elements, in that
their computed height and width are not meant to be used for layout.
Instead, we now calculate suitable widths and heights based on the
contents of the table wrapper when performing absolute layout.
Fixes the layout of
http://wpt.live/css/css-position/position-absolute-center-007.html
All of this error propogation came from a single call to
HashMap::try_ensure_capacity! As part of the ongoing effort to ignore
small allocation failures, lets just assert this works. This has the
nice side-effect of propogating out to a few other classes.
Before this change, we only considering `grid-auto-flow` to determine
whether a row or column should be added when there was not enough space
in the implicit grid to fit the next unplaced item.
Now, we also choose the direction in which the "auto placement cursor"
is moved, based on the auto flow property.
This will allow resolving paths that use sizes that are relative to the
viewport. This necessarily removes the on element caching, which has
been redundant for a while as computed paths are stored on the
paintable.
...to avoid allocating a copy of glyph run for painting commands. We
can't simply save pointers to a glyph run in layout/paintable tree
because it should be safe to deallocate layout and paintable trees
after painting commands are recorded, if in the future we decide to
move command execution to a separate thread.
This solves a particular issue with SVG as flex items, where the SVG has
an intrinsic aspect ratio via its viewBox, but no explicit natural width
or height.
Makes all corporate sponsor logos show up on https://ziglang.org/ :^)
If the layout has been recalculated and the sizes of scrollable
overflow rectangles could have changed, we need to ensure that scroll
offsets remain within the valid range.
Height definiteness is now preserved as intended by CSS-SIZING-3
(assuming I've understood it correctly) and not implicitly granted by
layout algorithms when they assign height.
For the specific special/magical cases where some sizes become definite
during layout, the preceding commits have made them explicit in code.
This fixes a number of flex layout issues where we were previously
resolving percentage values against post-layout flex container heights,
but other browsers don't.
Fixing this function will be quite an undertaking since a *lot* of code
relies on set_content_width() implicitly flipping the definiteness of
the width. It is wrong though, so we do need to fix it eventually.
In particular, these two interesting cases:
- The containing block of an abspos box is always definite from the
perspective of the abspos box.
- When resolving abspos box sizes from two opposing fixed insets,
we now mark those sizes as definite (since no layout was required
to resolve them).
The whole way we lay out SVG content is ad-hoc, so this doesn't follow
any particular spec. However, our viewport transform logic depends on
having definite sizes, so let's just mark them as such for now.
This will be required for percentages to resolve against it correctly
after we make set_content_height() not automatically mark heights as
definite sizes.
The CSS-FLEXBOX-1 spec has a bunch of special cases where sizes are
considered definite after reaching a specific point of the layout
algorithm.
Before this change, we were relying on set_content_width/height also
implicitly marking those content sizes as definite.
To prepare for that implicit behavior going away, this patch makes
the special cases explicit.
Before this change, we were always assigning the calculated height to
each block container after laying it out in BFC.
This should really only happen during intrinsic sizing, since that is
how measurements are communicated to the client there.
With this change "max-width: max-content" is treated as "none" when
the available width is also "max-content". This fix prevents a stack
overflow in the grid track size maximization algorithm by avoiding
recursive calls to calculate_max_width() when determining the maximum
grid container size.
They currently assume the DOM node is an HTMLImageElement with respect
to handling the alt attribute. The HTMLInputElement will require the
same behavior.