This is a monster patch that turns all EventTargets into GC-allocated
PlatformObjects. Their C++ wrapper classes are removed, and the LibJS
garbage collector is now responsible for their lifetimes.
There's a fair amount of hacks and band-aids in this patch, and we'll
have a lot of cleanup to do after this.
Similar to create() in LibJS, wrap() et al. are on a low enough level to
warrant passing a Realm directly instead of relying on the current realm
from the VM, as a wrapper may need to be allocated while no JS is being
executed.
This takes care of two FIXMEs and fixes an issue on Google Docs where
we'd mix boxes from different documents in the same layout tree.
(This happened because shadow trees remained attached to their old
document when their host was adopted.)
There's no need to have a custom is_scripting_enabled() for the
Document class, as it (indirectly) inherits from Node.
Also, let's not hardcode false here :^)
Input events have nothing to do with layout, so let's not send them to
layout nodes.
The job of Paintable starts to become clear. It represents a paintable
item that can be rendered into the viewport, which means it can also
be targeted by the mouse cursor.
The "paintable" state in Layout::Box was actually not safe to access
until after layout had been performed.
As a first step towards making this harder to mess up accidentally,
this patch moves painting information from Layout::Box to a new class:
Painting::Box. Every layout can have a corresponding paint box, and
it holds the final used metrics determined by layout.
The paint box is created and populated by FormattingState::commit().
I've also added DOM::Node::paint_box() as a convenient way to access
the paint box (if available) of a given DOM node.
Going forward, I believe this will allow us to better separate data
that belongs to layout vs painting, and also open up opportunities
for naturally invalidating caches in the paint box (since it's
reconstituted by every layout.)
Instead of just the outline, fill them with some semi-transparent color.
Also add tag name, ID, classes and coordinates to the little tooltip.
Finally, use the border box instead of the context box for metrics,
same as other browsers.
Instead of making each Layout::Node compute style for itself, we now
compute it in TreeBuilder before even calling create_layout_node().
For non-element DOM nodes, we create the style and layout tree node
in TreeBuilder. This allows us to move create_layout_node() from
DOM::Node to DOM::Element.
This changes allows for nested browser contexts to be embedded in the
serialized JSON of their container element (like `iframe`) and enables
their inspection in the DOM Inspector.
Use a simple heuristic to exclude uninteresting whitespace and
de-clutter the inspector's DOM tree.
Uninteresting whitespace is currently one of these:
- Non-rendered whitespace-only text nodes
- Rendered whitespace-only text nodes between block-level elements
The previous implementation was about a half implementation and was
tied to Element::innerHTML. This separates it and puts it into
HTMLDocumentParser, as this is in the parsing section of the spec.
This provides a near finished HTML fragment serialisation algorithm,
bar namespaces in attributes and the `is` value.
The current implementation felt a bit ad-hoc and notably allowed
textContent to operate on all node types. It also only returned the
child text content of the Node instead of the descendant text content.
We maintain a directory of ID -> Node. Nodes add themselves to this
directory when they are created, receiving a random ID. When a Node is
destroyed, it removes itself from this directory. Anyone can request a
Node from the directory by its ID using `Node::from_id()`.
We reserve the `0` ID to mean "none".
These IDs allow different processes to communicate about a given Node
over IPC, for example the DOM Inspector.
An svg layout element without a `SVGSVGElement` ancestor caused a failed
assertion before, because the svg context does not exist when `paint()`
is called
Nodes implementing the adoption steps can modify the passed in
document, for example HTMLTemplateElement does so to adopt it's
contents into the new document.
