The previous implementation assumed that the contents of `supports()`
was either a raw declaration, or a block containing some number of them.
This meant we wouldn't parse things like `supports(not (a:b))` or
`supports(selector(*))`.
`parse_a_supports()` actually does what we want in every case except for
raw declarations (`supports(a: b)`), so let's always call it first, and
then fall back to parsing a single declaration.
This works by generating random values using XorShift128PlusRNG at
compute time and then caching them on the document using the relevant
random-caching-key
In a few places, user code wants to parse a `<color>` or `<length>` etc,
but we didn't have a way to do so, so they would do something
similar-ish instead, like parse the value of the `color` property.
Let's make that available instead.
Some contexts (e.g. descriptors, media conditions) don't allow tree
counting functions, this commit adds an easy way to check if the current
value context is one of those.
Previously we would always use the window's viewport which was incorrect
if we were within an iframe.
This is likely applicable to all uses of
`Length::ResolutionContext::for_window`.
The spec is a bit awkward here: A few algorithms create an "empty"
SourceSet, and then assign its source-size value a few steps later, so
we have a temporary state with no length. In order to avoid complicating
the types with Optional, I've chosen to just assign it to 0px.
Previously we used `auto`, but `auto` is not a valid value here - it is
used inside the "parse a sizes attribute" algorithm, but that always
returns an actual length (or calc).
This reverts 0e3487b9ab.
Back when I made that change, I thought we could make our StyleValue
classes match the typed-om definitions directly. However, they have
different requirements. Typed-om types need to be mutable and GCed,
whereas StyleValues are immutable and ideally wouldn't require a JS VM.
While I was already making such a cataclysmic change, I've moved it into
the StyleValues directory, because it *not* being there has bothered me
for a long time. 😅
- Omit calcs that are resolved to `0px` from the serialized value
- Allow CSV to be the 'Z' component in interpolated value.
- Allow calcs with mixed percentages in the first two arguments.
To achieve the third item above the concept of a "special" value parsing
context has been added - this will also be useful for instance for
different arguments of color functions having different contexts.
Gains us 23 WPT tests
Add global registry for registered properties and partial support
for `@property` rule. Enables registering properties with initial
values. Also adds basic retrieval via `var()`.
Note: This is not a complete `@property` implementation.
To be vendor-prefixed, an ident has to start with a '-', then have
another '-' later. If the ident simply starts with a '-' then that's
perfectly fine.
Fixes 62 in-tree WPT subtests. :^)
There's discussion in the linked spec issue, but the short version is,
this algorithm will see "foo,bar," as a list of two groups, with "foo"
in the first group and "bar" in the second. However, users of this want
to get a list of three groups, with the last one being empty. So, do
that!
This is a bit under-specced, specifically there's no definition of
CSSMarginDescriptors so I've gone with CSSStyleProperties for now. Gets
us 17 WPT subtests.
Keep track of which CSSRule owns a CSSRuleList, and then use that to
produce a stack of RuleContexts for the CSS Parser to use.
There are certainly other places we should do this!
We have two different code paths that implement the "parse a CSS
declaration block" algorithm, for properties and descriptors. COmbining
them isn't straightforward, and doesn't seem especially useful.
Previously, `CSSStyleSheet.replace()` and `CSSStyleSheet.replaceSync()`
parsed the given CSS text into a temporary stylesheet object, from
which a list of rules was extracted. Doing this had the unintended
side-effect that a fetch request would be started if the given CSS text
referenced any external resources. This fetch request would cause a
crash, since the temporary stylesheet object didn't set the constructed
flag, or constructor document. We now parse the given CSS text as a
list of rules without constructing a temporary stylesheet.
These actually always return a value, despite the `CSSStyleSheet*`
return type. So, make that clearer by returning `GC::Ref<CSSStyleSheet>`
instead. This also means we can remove some ad-hoc error-checking code.
To prepare for introducing a CSS::URL type, we need to qualify any use
of LibURL as `::URL::foo` instead of `URL::foo` so the compiler doesn't
get confused.
Many of these uses will be replaced, but I don't want to mix this in
with what will likely already be a large change.
For example, `@font-face` is not only invalid inside a style rule, it's
also invalid inside a child of a style rule. This fixes a test
regression that we previously passed by accident.
The goal here is to do something a bit smarter with the parsing here
than we do for properties. Instead of the JSON saying "here are the
values, and here are the keywords, and we can have up to 3", here we
place the syntax in the JSON directly (though currently broken up as
one string per option) and then we attempt to parse each one in
sequence. It's something we'll need eventually for `@property` among
other things.
...However, in this first pass, I've gone with the simplest option of
hard-coding the types instead of figuring them out properly. So there's
a PositivePercentage type and a UnicodeRangeTokens type, instead of
properly implementing the grammar for those in a generic way.
This is used for default UA style right now, and we'll expand its use in
the near future.
Note that this required teaching the CSS parser to handle url()
functions when there's no document URL to resolve them against. If we
don't handle that, namespace rules in UA style don't parse correctly.