Track last-child and backward positional selector dependencies
separately on parent nodes. A last-child or only-child selector can only
change the element at the trailing edge, so insertions and removals can
invalidate that element directly instead of walking every previous
sibling.
Keep the previous-sibling walk for selectors such as nth-last-child and
last-of-type, where every previous element's from-end position may
change.
Represent WebIDL C++ types with a single CppType model that tracks
nullability, optional presence, and contained storage.
GC-like values now use GC::Ref/GC::Ptr directly, while containers choose
"plain", "Root", or "Conservative" container types depending on what
they contain. For example, sequence<Element> becomes a RootVector of
GC::Ref values, while sequence<SomeDictionary> becomes a
ConservativeVector only when the dictionary contains GC-like values.
This moves the generated bindings away from wrapping GC values in
GC::Root by default.
This has broad fallout as the types passed to interfaces for GC
objects changes almost fully across the board.
We now track when a parent has a child affected by a backward structural
pseudo-class. These are selectors whose match result for an element can
depend on siblings after that element, such as `:last-child`,
`:only-child`, `:last-of-type`, `:only-of-type`, `:nth-last-child`, and
`:nth-last-of-type`.
When inserting or removing a node, previous siblings only need style
invalidation if one of them was matched against such a selector. Use the
parent-level flag to skip the previous-sibling walk when no child under
that parent can be affected.
This saves a lot of invalidation work on sites that insert a lot of
nodes into the DOM via JS.
By making use of the WEB_PLATFORM_OBJECT macro we can remove
the boilerplate of needing to add this override for every
serializable platform object so that we can check whether they
are exposed or not.
Every user of this actually wants an ancestor in the flat tree - taking
things like `<slot>` into account. So rename it and adjust its behavior
to use that.
With this change we maintain a data structure that maps ids to
corresponding elements. This allows us to avoid tree traversal in
getElementById() in all cases except ones when lookup happens for
unconnected elements.
Resulting in a massive rename across almost everywhere! Alongside the
namespace change, we now have the following names:
* JS::NonnullGCPtr -> GC::Ref
* JS::GCPtr -> GC::Ptr
* JS::HeapFunction -> GC::Function
* JS::CellImpl -> GC::Cell
* JS::Handle -> GC::Root
Now that we have RTTI in userspace, we can do away with all this manual
hackery and use dynamic_cast.
We keep the is<T> and downcast<T> helpers since they still provide good
readability improvements. Note that unlike dynamic_cast<T>, downcast<T>
does not fail in a recoverable way, but will assert if the object being
casted is not a T.
...{All} to ParentNode. Exposes createDocumentFragment and
createComment on Document. Stubs out the document.body setter.
Also adds ParentNode back :^).
This requires moving remove_all_children() from ParentNode to
Node, which makes ParentNode.cpp empty, so remove it.
It also co-opts the existing Node::text_content() method and
tweaks it slightly to fit the semantics of Node.textContent.
LibWeb keeps growing and the Web namespace is filling up fast.
Let's put DOM stuff into Web::DOM, just like we already started doing
with SVG stuff in Web::SVG.