I've chosen the name `AttributeParser` since it parses data from
attributes. Rather than duplicate the parsing of numbers and other
basic types, let's make use of this existing parsing code for parsing
the data for `<line>`, `<polyline>`, etc.
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 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.
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.
Most of the time, we cannot resolve a `calc()` expression until we go to
use it. Since any `<length-percentage>` can legally be a `calc
()`, let's store it in `LengthPercentage` rather than make every single
user care about this distinction.
`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.
This patch adds a new mechanism that allows InlineFormattingContext to
build line boxes incrementally instead of all-in-one go.
Incremental build will eventually allow much better support for CSS
floating objects.
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.
This is a simple implementation of SubtleCrypto.digest() using LibCrypto
under the hood, so it supports all the required hash functions:
SHA-1, SHA-256, SHA-384, SHA-512.
Two FIXMEs remain: doing the hashing "in parallel", and supporting an
object argument instead of a plain string.
All CSS loading is now done by the relevant classes:
- CSSImportRule, which loads its linked stylesheet
- HTMLStyleElement, which "loads" its contents
- HTMLLinkElement, which loads its linked stylesheet
This works at the Token level, which is quick and easy but has
drawbacks: We don't know when something is a property name or a value,
or if something is part of a selector. But, this works for now.
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.
:^)
This is the `CSS` namespace defined in IDL here:
https://www.w3.org/TR/cssom-1/#namespacedef-css , not to be confused
with our `Web::CSS` namespace. Words are hard.
`CSS.escape()` lets you escape identifiers that can then be used to
create a CSS string.
I've also stubbed out the `CSS.supports()` function.
'static' for a function means that the symbol shall not be made public
for the result of the current compilation unit. This does not make sense
in a header, especially not if it's a large function that is used in
more than one place and not that performance-sensitive.
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.
