This is not a complete implementation of API, since we're also supposed
to accept an options dictionary as the third argument. However, a lot of
web content uses the boolean variant, and it's trivial to support.
I can't imagine how this happened, but it seems we've managed to
conflate the "event listener" and "EventListener" concepts from the DOM
specification in some parts of the code.
We previously had two things:
- DOM::EventListener
- DOM::EventTarget::EventListenerRegistration
DOM::EventListener was roughly the "EventListener" IDL type,
and DOM::EventTarget::EventListenerRegistration was roughly the "event
listener" concept. However, they were used interchangeably (and
incorrectly!) in many places.
After this patch, we now have:
- DOM::IDLEventListener
- DOM::DOMEventListener
DOM::IDLEventListener is the "EventListener" IDL type,
and DOM::DOMEventListener is the "event listener" concept.
This patch also updates the addEventListener() and removeEventListener()
functions to follow the spec more closely, along with the "inner invoke"
function in our EventDispatcher.
ACID3 test page throws exception about document.write. Let's at least
get rid of it by defining these stubs.
I added document.writeln too because it is similar.
getClientRects supposed to return a list of bounding DOMRect
for each box fragment of Element's layout, but most elements have
only one box fragment, so implementing it with getBoundingClientRect
is useful.
BFC currently has a number of architectural issues due to it being
responsible for setting the dimensions of the BFC root.
This patch moves the logic for setting up the ICB from BFC to Document.
This patch introduces the StyleComputer::RuleCache, which divides all of
our (author) CSS rules into buckets.
Currently, there are two buckets:
- Rules where a specific class must be present.
- All other rules.
This allows us to check a significantly smaller set of rules for each
element, since we can skip over any rule that requires a class attribute
not present on the element.
This takes the typical numer of rules tested per element on Discord from
~16000 to ~550. :^)
We can definitely improve the cache invalidation. It currently happens
too often due to media queries. And we also need to make sure we
invalidate when mutating style through CSSOM APIs.
Previously we would re-run the entire CSS selector machinery for each
property resolved. Instead of doing that, we now resolve a final set of
custom property key/value pairs at the start of the cascade.
This is a naive-but-somewhat-functional initial implementation of
HTML Storage.
Note that there is no persistence yet, everything is in-process only,
and one local Storage object per origin.
This overrides the JS host hooks to follow the spec for queuing
promises, making/calling job callbacks, unhandled promise rejection
handling and FinalizationRegistry queuing.
This also allows us to drop the on_call_stack_emptied hook in
Document::interpreter().
This isn't perfect (especially the global object situation in
activate_event_handler), but I believe it's in a much more complete
state now :^)
This fixes the issue of crashing in prepare_for_ordinary_call with the
`i < m_size` crash, as it now uses the IDL callback functions which
requires the Environment Settings Object. The environment settings
object for the callback is fetched at the time the callback is created,
for example, WrapperGenerator gets the incumbent settings object for
the callback at the time of wrapping. This allows us to remove passing
in ScriptExecutionContext into EventTarget's constructor.
With this, we can now drop ScriptExecutionContext.
The environment settings object is effectively the context a piece of
script is running under, for example, it contains the origin,
responsible document, realm, global object and event loop for the
current context. This effectively replaces ScriptExecutionContext, but
it cannot be removed in this commit as EventTarget still depends on it.
https://html.spec.whatwg.org/multipage/webappapis.html#environment-settings-object
This commit removes all exception related code:
Remove VM::exception(), VM::throw_exception() etc. Any leftover
throw_exception calls are moved to throw_completion.
The one method left is clear_exception() which is now a no-op. Most of
these calls are just to clear whatever exception might have been thrown
when handling a Completion. So to have a cleaner commit this will be
removed in a next commit.
It also removes the actual Exception and TemporaryClearException classes
since these are no longer used.
In any spot where the exception was actually used an attempt was made to
preserve that behavior. However since it is no longer tracked by the VM
we cannot access exceptions which were thrown in previous calls.
There are two such cases which might have different behavior:
- In Web::DOM::Document::interpreter() the on_call_stack_emptied hook
used to print any uncaught exception but this is now no longer
possible as the VM does not store uncaught exceptions.
- In js the code used to be interruptable by throwing an exception on
the VM. This is no longer possible but was already somewhat fragile
before as you could happen to throw an exception just before a VERIFY.
This property represents the CSS content size, so let's reduce ambiguity
by using the spec terminology.
We also bring a bunch of related functions along for the ride.
Style updates are lazy since late last year, so the StyleInvalidator is
actually hurting us more than it's helping by running the entire CSS
selector machine on the whole DOM for every attribute change.
Instead, simply mark the entire DOM dirty and let the lazy style update
mechanism run *once* on next event loop iteration.
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.
`convert_nodes_to_single_node` is inside its own file so ChildNode can
include and use it without having to include other headers such as
DOM/Node.h. This is to prevent circular includes.