Previously, if a transition property was not wrapped in a list, it
would be replaced with the default value in
`StyleComputer::compute_transitioned_properties`.
Keep track of which CSSRule owns a CSSRuleList, and then use that to
produce a stack of RuleContexts for the CSS Parser to use.
There are certainly other places we should do this!
The spec algorithm changed at some point to support nested declarations,
but I only just noticed. The subtest regression is one we were passing
incorrectly.
We have two different code paths that implement the "parse a CSS
declaration block" algorithm, for properties and descriptors. COmbining
them isn't straightforward, and doesn't seem especially useful.
Before this change, we were going through the chain of base classes for
each IDL interface object and having them set the prototype to their
prototype.
Instead of doing that, reorder things so that we set the right prototype
immediately in Foo::initialize(), and then don't bother in all the base
class overrides.
This knocks off a ~1% profile item on Speedometer 3.
Before this change, we were waiting for Document to lazily evaluate
sheet media and media rules. This often meant that we'd get two
full-document style invalidations: one from adding a new style sheet,
and one from the media queries changing state.
By evaluating the rules eagerly on insertion, we coalesce the two
invalidations into one. This reduces the number of full-document
invalidations on Speedometer 3 from 51 to 34.
We achieve this by keeping track of all checked pseudo class selectors
in the SelectorEngine code. We also give StyleComputer per-pseudo-class
rule caches.
Previously, `CSSStyleSheet.replace()` and `CSSStyleSheet.replaceSync()`
parsed the given CSS text into a temporary stylesheet object, from
which a list of rules was extracted. Doing this had the unintended
side-effect that a fetch request would be started if the given CSS text
referenced any external resources. This fetch request would cause a
crash, since the temporary stylesheet object didn't set the constructed
flag, or constructor document. We now parse the given CSS text as a
list of rules without constructing a temporary stylesheet.
We now don't absolutize the URL during parsing, keeping it as a CSS::URL
object which we then pass to the "fetch an external image for a
stylesheet" algorithm. Our version of this algorithm is a bit ad-hoc,
in order to make use of SharedResourceRequest. To try and reduce
duplication, I've pulled all of fetch_a_style_resource() into a static
function, apart from the "actually do the fetch" step.
The CSS `fetch_foo()` functions resolve the URL relative to the
CSSStyleSheet if one is provided. So, style values that do so need to
know what CSSStyleSheet they are part of so that, for example, `url
(foo.png)` is loaded relative to the style sheet's URL instead of the
document's one.
That all works without this change because we currently absolutize URLs
during parsing, but we're in the process of stopping that.
This commit adds the infrastructure for telling style values what their
CSSStyleSheet is.
See the spec issue in the comments for details. There are situations
where we will need to call this but don't have a CSSStyleSheet to pass
in, but we always have a Document, so use that where possible.
These actually always return a value, despite the `CSSStyleSheet*`
return type. So, make that clearer by returning `GC::Ref<CSSStyleSheet>`
instead. This also means we can remove some ad-hoc error-checking code.
The spec is unclear about when exactly we should parse the style sheet.
Previously we'd do so before calling this algorithm, which was
error-prone, as seen by the bug fixed by the previous commit. The spec
for step 1 of "create a CSS style sheet" says:
1. Create a new CSS style sheet object and set its properties as
specified.
The definitions linked are UA-defined enough that it seems reasonable to
put the parsing here. That simplifies the user code a little and makes
it harder to mess up. It does raise the question of what to do if
parsing fails. I've matched our previous behaviour by just logging and
returning in that case.
While I'm modifying this method, I've also converted the bool params to
enums so they're a little clearer to read.
This fixes one source of flakiness on WPT (of many) where we wouldn't
recompute style after programmatically altering the contents of a style
sheet, but instead had to wait for something else to cause invalidation.
With this change we save a copy of of scroll state at the time of
recording a display list, instead of actual ScrollState pointer that
could be modifed by the main thread while display list is beings
rasterized on the rendering thread, which leads to a frame painted with
inconsistent scroll state.
Fixes https://github.com/LadybirdBrowser/ladybird/issues/4288
See the linked spec issue for more details. The MediaList can be null
internally, and this was upsetting GCC as it meant our bindings code
was dereferencing a null pointer.
