We had two issues with ::backdrop which this commit fixes:
::backdrop is unique in that it's the previous sibling to its
originating element, instead of a child of it. This means when that
element's layout node is thrown away, the ::backdrop's is not.
A second issue is that if we do a partial layout rebuild, the
originating element's layout node replaces its previous one, but we
would still append a new layout node for ::backdrop to the root, so it
would appear in front of the originating element.
A related issue is that clear_pseudo_element_nodes() got called on the
element after its ::backdrop had been assigned, so it would immediately
lose track of it again.
To solve this, we now always remove the ::backdrop's layout node. If we
need to create a new one, we insert it before the element's layout node
if it has one, otherwise we append as before. This ensures we only ever
have up to one layout node for the ::backdrop, and it appears behind
its originating element.
To support this, create_pseudo_element_if_needed() has a couple of
changes:
- It returns the node that was created.
- The caller can ask it not to insert the node, so that the caller can
do so (which we use so that we can insert it in a specific place)
The upcoming generated types will match those for pseudo-classes: A
PseudoElementSelector type, that then holds a PseudoElement enum
defining what it is. That enum will be at the top level in the Web::CSS
namespace.
In order to keep the diffs clearer, this commit renames and moves the
types, and then a following one will replace the handwritten enum with
a generated one.
This was mainly a matter of deferring the wrapping of the button's
children until after its internal layout tree has been constructed.
That way we don't lose any pseudo elements spawned along the way.
Fixes#2397.
Fixes#2399.
Our layout tree requires that all containers either have inline or
non-inline children. In order to support the layout of non-inline
elements inside inline elements, we need to do a bit of tree
restructuring. It effectively simulates temporarily closing all inline
nodes, appending the block element, and resumes appending to the last
open inline node.
The acid1.txt expectation needed to be updated to reflect the fact that
we now hoist its <p> elements out of the inline <form> they were in.
Visually, the before and after situations for acid1.html are identical.
DOM nodes now have two additional flags:
- Needs layout tree update
- Child needs layout tree update
These work similarly to the needs-style-update flags, but instead signal
the need to rebuild the corresponding part of the layout tree.
When a specific DOM node needs a layout tree update, we try to create
a new subtree starting at that node, and then replace the subtree in the
old layout tree with the newly created subtree.
This required some refactoring in TreeBuilder so that we can skip over
entire subtrees during a tree update.
Note that no partial updates happen yet (as of this commit) since we
always invalidate the full layout tree still. That will change in the
next commit.
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
This patch implements the "remove irrelevant boxes" and "generate
missing child wrappers" parts of table fixup.
"Generate missing parents" is left as a task for our future selves.
Layout nodes now only carry CSS computer values with them. The main
idea here is to give them only what they need to perform layout, and
leave the rest back in the DOM.
Inline layout nodes cannot have block children (except inline-block,
of course.)
When encountering a block box child of an inline, we now hoist the
block up to the inline's containing block, and also wrap any preceding
inline siblings in an anonymous wrapper block.
This improves the ACID2 situation quite a bit (although we still need
floats to really bring it home.)
I also took this opportunity to move all tree building logic into
Layout::TreeBuilder, to continue the theme of absolving our LayoutNode
objects of responsibilities. :^)
