"5em" means 5*font-size, but by forcing "em" to mean the presentation
size of the bitmap font actually used, we broke a bunch of layouts that
depended on a correct interpretation of "em".
This means that "em" units will no longer be relative to the exact
size of the bitmap font in use, but I think that's a compromise we'll
have to make, since accurate layouts are more important.
This yields a visual progression on both ACID2 and ACID3. :^)
The ICB (initial containing block) gets its style from StyleComputer's
create_document_style(). It's basically a generic style for the root of
the layout tree.
With this patch, we now assign the width and height of the viewport rect
as two CSS "px" lengths to the "width" and "height" properties of the
ICB style. (Previously they were just defaulting to "auto" and we
assigned override dimensions during layout.)
This fixes an issue where position:absolute elements with relative width
and/or height were not dimensioned correctly, since the values were
relative to the width and/or height of the ICB style.
Although it is not said that some of the elements need to be italic,
*most* browsers mark them as such to distinguish them from the normal
text, so let's do that too!
This also adds a variant of {add,remove}_event_listener called
{add,remove}_event_listener_with_options.
This is used internally to perform {add,remove}_event_listener with a
default constructed options struct. It was done like this because
default constructing the Variant with the options struct requires the
struct defintions to be present, which requires us to include
AbortSignal.h, which would cause a circular include as AbortSignal.h
includes EventTarget.h.
After style computation, every StyleProperties has a value for every
PropertyID. Given this, it's simpler, faster and less memory-heavy to
use an Array instead of a HashMap. :^)
Nobody makes undefined Lengths now, (although actually removing
Undefined will come in a later commit) so we can remove this parameter,
and `resolved_or_auto()`/`resolved_or_zero()`.
Depending on the type of the calc() expression, the percentage_basis has
to be the same dimension type. Several places were already passing `
{}` for this, so let's make that an empty Variant instead of an
undefined Length. :^)
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.
When converting this code to use Optional, I accidentally left in the
initialization, so it *always* had a value, and always created a Length
from it. Oops.
As noted, this is not entirely right, since we are using the computed
font's metrics instead of the initial font's metrics, but we do not
have a good way to obtain the latter.
If we try to @import a stylesheet that was already cached, we'll get a
synchronous resource_did_load() callback. Because of this, it's
necessary to set up the document load event delayer *before* calling
set_resource(), as otherwise we'd be stuck without a load event forever.
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.
- Replace "auto" with "auto const" where appropriate.
- Remove an unused struct.
- Make sort_matching_rules() a file-local static function.
- Remove some unnecessary includes.
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.
We also pass whether the shadow goes inside or outside the element. Only
outer shadows are rendered currently, and inner ones may want to be
handled separately from them, as they will never interfere with each
other.
The pattern we've adopted for other multi-value properties is to run in
a loop like this, since that makes it easier to cater for values
appearing in different orders.
