We basically need to do this for every invocation of invalidate_style()
right now, so let's just do it inside invalidate_style() itself.
Fixes one missing invalidation issue caught by a WPT test. :^)
This sucks, and we're gonna have to do better, but for now let's
invalidate the whole document's style, so that we get correct behavior
if there are :has() selectors present.
With 6a549f6270 we need to check if
optional scrollable overflow exists for paintable box, because it's not
computed for inline nodes.
Fixes crashing after navigating into direct messages screen on Discord.
This is strictly nicer than passing them around as i32 everywhere,
and by switching to i64 as the underlying type, ID allocation becomes as
simple as incrementing an integer.
InlinePaintable was an ad-hoc paintable type required to support the
fragmentation of inline nodes across multiple lines. It existed because
there was no way to associate multiple paintables with a single layout
node. This resulted in a lot of duplicated code between PaintableBox and
InlinePaintable. For example, most of the CSS properties like
background, border, shadows, etc. and hit-testing are almost identical
for both of them. However, the code had to be duplicated to account for
the fact that InlinePaintable creates a box for each line. And we had
quite many places that operate on paintables with a code like:
```
if (box.is_paintable_box()) {
// do something
} else (box.is_inline_paintable()) {
// do exactly the same as for paintable box but using InlinePaintable
}
```
This change replaces the usage of `InlinePaintable` with
`PaintableWithLines` created for each line, which is now possible
because we support having multiple paintables per layout node. By doing
that, we remove lots of duplicated code and bring our implementation
closer to the spec.
These don't have to worry about the input not being valid UTF-8 and
so can be infallible (and can even return self if no changes needed.)
We use this instead of Infra::to_ascii_{upper,lower}_case in LibWeb.
There was no need to use FlyString for error messages, and it just
caused a bunch of churn since these strings typically only existed
during the lifetime of the error.
Previously, we set the "needs style update" flag to false at the
beginning of recomputing the style. This meant that if any code within
the cascade set this flag to true, then we would end style computation
thinking the element still needed its style updating. This could occur
when starting a transition, and would make TreeBuilder crash.
By ensuring that we always set the flag to false at the very end of
style computation, this is avoided, along with any similar issues - I
noticed a comment in `Animation::cancel()` which sounds like a
workaround was needed for a similar problem previously.
Computing the "contained text auto directionality" is now its own
algorithm, with an extra parameter, and is additionally called from
step 2.1.3.2 instead of calling "auto directionality".
When setting an element attribute to the value it already had, we don't
need to update style or invalidate anything that depends on the DOM
version counter.
This was a source of much pointless busywork.
You can now build with STYLE_INVALIDATION_DEBUG and get a debug stream
of reasons why style invalidations are happening and where.
I've rewritten this code many times, so instead of throwing it away once
again, I figured we should at least have it behind a flag.
When accessed on the root/document element, the following properties are
derived from the viewport, not layout-dependent metrics:
- scrollLeft
- scrollTop
- scrollWidth
- scrollHeight
We now avoid synchronous layout in such cases. This was causing some
unnecessary layout work when loading https://vercel.com/
Use offset from ScrollFrame which is an actual value a box is shifted by
while painting.
Also change `update_paint_and_hit_testing_properties_if_needed()` to
refresh scroll frames state, because `getBoundingClientRect()` now
depends on them.
Fixes wrong file tree sidebar location and excessive layout
invalidations caused by some miscalculation on JS-side when wrong
bounding client rect is provided on Github PR pages like
https://github.com/LadybirdBrowser/ladybird/pull/1232/files
Before this change, we would go through every known pseudo element and
compute style for it whenever recomputing the style of an element.
This led to disastrous performance on pages with selectors like
`::selection` or `::placeholder`, as they'd effectively match every
single element and thus we'd compute multiple additional styles for
every element in the DOM.
The fix is simple: only recompute `before` and `after` pseudo element
styles, since those are the only two pseudo elements that generate
*new* nodes -- other pseudo elements refer to (possibly) existing
nodes or concepts within the DOM (or internal shadow DOM).
This makes style updates take ~40ms on our GitHub repo instead of
~220ms. It's still slower than it should be, but a huge improvement.
For a long time, we've used two terms, inconsistently:
- "Identifier" is a spec term, but refers to a sequence of alphanumeric
characters, which may or may not be a keyword. (Keywords are a
subset of all identifiers.)
- "ValueID" is entirely non-spec, and is directly called a "keyword" in
the CSS specs.
So to avoid confusion as much as possible, let's align with the spec
terminology. I've attempted to change variable names as well, but
obviously we use Keywords in a lot of places in LibWeb and so I may
have missed some.
One exception is that I've not renamed "valid-identifiers" in
Properties.json... I'd like to combine that and the "valid-types" array
together eventually, so there's no benefit to doing an extra rename
now.
If a DOM node is an element with pseudo-elements, but it has no child
DOM nodes and is not a shadow host, then the code that serializes its
pseudo-elements would get skipped, making them not show up in the
inspector.
I previously believed there was no way a detached document should have
layout information, but it turns out there is a way: getComputedStyle().
So we need to account for cases where we have a layout node, but no
navigable, since that is a state we can get into at this moment.
Fixes#354
This also fixes a bug where task IDs were being deallocated from the
wrong IDAllocator. I don't know if it was actually possible to cause any
real trouble with that mistake, nor do I know how to write a test for
it, but this makes the bug go away.
We were saving to source declarations for *every* property, even though
we only ever looked it up for animation-name.
This patch gets rid of the per-property source pointer and we now keep
a single pointer to the animation-name source only.
This shrinks StyleProperties from 6512 bytes to 4368 bytes per instance.
Previously, pseudo-elements had their style computed while the layout
tree was being built. Instead, do so inside Element::recompute_style(),
using the same invalidation mechanism that the element itself uses.
This also has the effect of invalidating the layout much less often.
Pseudo-elements' style is only computed while building the layout tree.
This meant that previously, they would not have their style recomputed
in some cases. (Such as when :hover is applied to an ancestor.)
Now, when recomputing an element's style, we also return a full
invalidation if one or more pseudo-elements would exist either before or
after style recomputation.
This heuristic produces some false positives, but no false negatives.
Because pseudo-elements' style is computed during layout building, any
computation done here is then thrown away. So this approach minimises
the amount of wasted style computation. Plus it's simple, until we have
data on what approach would be faster.
This fixes the Acid2 nose becoming blue when the .nose div is hovered.
These control the state of CSS counters.
Parsing code for `reversed(counter-name)` is implemented, but disabled
for now until we are able to resolve values for those.
This represents each element's set of CSS counters.
https://drafts.csswg.org/css-lists-3/#css-counters-set
Counters are resolved while building the tree. Most elements will not
have any counters to keep track of, so as an optimization, we don't
create a CountersSet object until the element actually needs one.
In order to properly support counters on pseudo-elements, the
CountersSet needs to go somewhere else. However, my experiments with
placing it on the Layout::Node kept hitting a wall. For now, this is
fairly simple at least.
The :host family of pseudo class selectors select the shadow host
element when matching against a rule from within the element's shadow
tree.
This is a bit convoluted due to the fact that the document-level
StyleComputer keeps track of *all* style rules, and not just the
document-level ones.
In the future, we should refactor style storage so that shadow roots
have their own style scope, and we can simplify a lot of this.
Previously, if a document had any element with a name attribute that
was set to the empty string, then `document.getElementsByName("")` and
`element.getElementsByName("")` would return a collection including
those elements.
Previously, if a document had an element whose id was the empty string,
then `document.getElementById("")` and `element.getElementById("")`
would return that element.
