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.
This initial implementation stubs out the WorkerGlobalScope,
WorkerLocation and WorkerNavigator classes. It doesn't take into account
all the things that actually need passed into the constructors for these
objects, nor the extra abstract operations that need to be performed on
them by the rest of the Browser infrastructure. However, it does create
bindings that compile and link :^)
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 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 is in a slightly weird state, where Percentages are sometimes
Lengths and sometimes not, which I will be cleaning up in subsequent
commits, in an attempt not to change all of LibWeb in one go. :^)
Length and Percentage are different types, and sometimes only one or the
other is allowed in a given CSS property. This is a first step towards
separating them.
This requires an implementation of the "text preparation algorithm" as
specified here:
html.spec.whatwg.org/multipage/canvas.html#text-preparation-algorithm
However, we're missing a lot of things such as the
CanvasTextDrawingStyles interface, so most of the algorithm was not
implemented. Additionally, we also are not able to use a LineBox like
the algorithm suggests, because our layouting infra is not up to the
task yet. The prepare_text function does nothing other than figuring out
the width of the given text and return glyphs with offsets at the
moment.
Just some boilerplate code to get started :^)
This adds both the SubtleCrypto constructor to the window object, as
well as the crypto.subtle instance attribute.
This represents a property value that hasn't been converted to a
"proper" StyleValue yet. That is, it's either a custom property's value,
or a value that includes `var()` references, (or both!) since neither of
those can be fully resolved at parse time.
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.
There's nothing really background-size-specific about this, but since
there is no `<size>` value type defined in the CSS spec at this time,
and background-size is the only user of it, I think this name makes more
sense. But I'm not 100% convinced.
This is done a bit differently from other properties: using a
TokenStream instead of just a Vector of ComponentValues. The reason for
this is, we can then use call the same function when parsing the
`background` shorthand. Otherwise, we would have to know in advance how
many values to pass down, which basically would involve duplicating the
`background-position` parsing code inside `background`.
The StyleValue is PositionStyleValue, since it represents a
`<position>`: https://www.w3.org/TR/css-values-4/#typedef-position
Unfortunately, background-position's parsing is a bit different from
`<position>`'s, (background-position allows 3-value syntax and
`<position>` doesn't) so we'll need to come back and write a different
parsing function for that later.
Note our Attribute class is what the spec refers to as just "Attr". The
main differences between the existing implementation and the spec are
just that the spec defines more fields.
Attributes can contain namespace URIs and prefixes. However, note that
these are not parsed in HTML documents unless the document content-type
is XML. So for now, these are initialized to null. Web pages are able to
set the namespace via JavaScript (setAttributeNS), so these fields may
be filled in when the corresponding APIs are implemented.
The main change to be aware of is that an attribute is a node. This has
implications on how attributes are stored in the Element class. Nodes
are non-copyable and non-movable because these constructors are deleted
by the EventTarget base class. This means attributes cannot be stored in
a Vector or HashMap as these containers assume copyability / movability.
So for now, the Vector holding attributes is changed to hold RefPtrs to
attributes instead. This might change when attribute storage is
implemented according to the spec (by way of NamedNodeMap).
Note there are a couple of type differences between the spec and the IDL
file added in this commit. For example, we will need to support a type
of Variant to handle spec types such as "(double or sequence<double>)".
But for now, this allows web pages to construct an IntersectionObserver
with any valid type.
This paves the way for the rejectionhandled and unhandledrejection
events.
It's also used by core-js (in browsers, at least) to check whether
Promise needs to be polyfilled, so adding it should allow more websites
to leverage LibJS's native Promise implementation :^)
The main thing missing is that we don't serialize the supports clause,
but for actually using a `@supports (something: cool) {}` rule in CSS,
it works!
The name is a little awkward, but this corresponds to the condition of a
`@supports` rule or the `CSS.supports("")` function.
A supports query only gets evaluated once, since its condition cannot
change during runtime. (We either support something or we don't, and the
spec specifically mentions that user preferences that disable features
do not affect the result here.) We keep a representation of it around
though, so that it can be serialized if needed. This is a little awkward
since we hold onto a `StyleDeclarationRule` which should be an internal
Parser class. This means making some Parser functions more public.
Potentially we could evaluate the Supports inside the Parser, and have
it only store a String representation of itself. But this works for now.
:^)
There's a subtle difference here. A "block box" in the spec is a
block-level box, while a "block container" is a box whose children are
either all inline-level boxes in an IFC, or all block-level boxes
participating in a BFC.
Notably, an "inline-block" box is a "block container" but not a "block
box" since it is itself inline-level.
Until now, we've internally thought of the CSS "display" property as a
single-value property. In practice, "display" is a much more complex
property that comes in a number of configurations.
The most interesting one is the two-part format that describes the
outside and inside behavior of a box. Switching our own internal
representation towards this model will allow for much cleaner
abstractions around layout and the various formatting contexts.
Note that we don't *parse* two-part "display" yet, this is only about
changing the internal representation of the property.
Spec: https://drafts.csswg.org/css-display
This introduces 3 classes: NodeList, StaticNodeList and LiveNodeList.
NodeList is the base of the static and live versions. Static is a
snapshot whereas live acts on the underlying data and thus inhibits
the same issues we have currently with HTMLCollection.
They were split into separate classes to not have them weirdly
mis-mashed together.
The create functions for static and live both return a NNRP to the base
class. This is to prevent having to do awkward casting at creation
and/or return, as the bindings expect to see the base NodeList only.
Since we don't support IDL typedefs or unions yet, the responsibility
of verifying the type of the argument is temporarily moved from the
generated Wrapper to the implementation.