The CSSOM spec tells us to potentially add up to three different IDL
attributes to CSSStyleDeclaration for every CSS property we support:
- A camelCased attribute, where a dash indicates the next character
should be uppercase
- A camelCased attribute for every -webkit- prefixed property, with the
first letter always being lowercase
- A dashed-attribute for every property with a dash in it.
Additionally, every attribute must have the CEReactions and
LegacyNullToEmptyString extended attributes specified on it.
Since we specify every property we support with Properties.json, we can
use that file to generate the IDL file and it's implementation.
We import it from the Build directory with the help of multiple import
base paths. Then, we add it to CSSStyleDeclaration via the mixin
functionality and inheriting the generated class in
CSSStyleDeclaration.
Attempt 2! Reverts 2a5dbedad4
This time, set up a different combinator when producing a relative
invalid selector rather than a standalone one. This fixes the crash.
Original description below for simplicity because it still applies.
---
Selectors like `:is(.valid, &!?!?!invalid)` need to keep the invalid
part around, even though it will never match, for a couple of reasons:
- Serialization needs to include them
- For nesting, we care if a `&` appeared anywhere in the selector, even
in an invalid part.
So this patch introduces an `Invalid` simple selector type, which simply
holds its original ComponentValues. We search through these looking for
`&`, and we dump them out directly when asked to serialize.
Selectors like `:is(.valid, &!?!?!invalid)` need to keep the invalid
part around, even though it will never match, for a couple of reasons:
- Serialization needs to include them
- For nesting, we care if a `&` appeared anywhere in the selector, even
in an invalid part.
So this patch introduces an `Invalid` simple selector type, which simply
holds its original ComponentValues. We search through these looking for
`&`, and we dump them out directly when asked to serialize.
Gap values are now represented by Variant<LengthPercentage, NormalGap>.
NormalGap is just an empty struct to represent the `normal` keyword.
This fixes a long-standing issue where we were incorrectly storing gaps
as CSS::Size, which led to us allowing a bunch of invalid gap values.
This seems to have vanished from the spec, but in any case, we still
need it. Without this change we erroneously thought that calculations
that match <percentage> did not match <number-percentage>.
We use the CSSRule::Type enum for identifying the type of a CSSRule, but
the spec requires that only some of these types are exposed via the
`type` attribute. For the rest, we're required to return 0, so let's do
so. :^)
Similar to LadybirdBrowser/ladybird#1714.
We don't implement the linejoin values `miter-clip` and `arcs`, because
according to the SVG 2 spec:
> The values miter-clip and arcs of the stroke-linejoin property are at
> risk. There are no known browser implementations. See issue Github
> issue w3c/svgwg#592.
Nothing uses this yet. The next step is to change
SVGPathPaintable::paint() to read `graphics_element.stroke_linejoin()`
and `graphics_element.stroke_miterlimit()` when painting.
This implementation is incomplete in that we do not fully implement the
steps to match the given font against the fonts in the set.
This is used by fonts.google.com to load the fonts used for sample text.
Ignoring the fact that we should serialize a simplified form of calc()
expressions, the following are wrong:
- grid-auto-columns
- grid-auto-rows
- grid-template-columns
- grid-template-rows
- transform-origin
Generated in part with this python script (though I've since iterated on
the output repeatedly so it's quite different):
```py
import json
properties_file = open("./Userland/Libraries/LibWeb/CSS/Properties.json")
properties = json.load(properties_file)
for (key, value) in properties.items():
if not 'valid-types' in value:
continue
if 'longhands' in value:
continue
valid_types = value['valid-types']
for type_string in valid_types:
name, *suffix = type_string.split(None, 1)
match name:
case 'integer' | 'number':
print(f'{key}: calc(2 * var(--n));')
case 'angle':
print(f'{key}: calc(2deg * var(--n));')
case 'flex':
print(f'{key}: calc(2fr * var(--n));')
case 'frequency':
print(f'{key}: calc(2hz * var(--n));')
case 'length':
print(f'{key}: calc(2px * var(--n));')
case 'percentage':
print(f'{key}: calc(2% * var(--n));')
case 'resolution':
print(f'{key}: calc(2x * var(--n));')
case 'time':
print(f'{key}: calc(2s * var(--n));')
```
Previously we would serialize these as the empty string. eg, this:
```
<div style="grid-auto-columns: auto"></div>
```
would have a computed `grid-auto-columns` value of ``.
This reverts 6d25bf3aac
Invalidating the style here means that transitions can cause an element
to leave style computation with its "needs style update" flag set to
true. This then causes a VERIFY to fail in the TreeBuilder.
This invalidation does not otherwise seem to have any effect. The
original commit suggests this was to fix a bug, but it's not clear what
bug that was. If it reappears, we can try to solve the issue in a
different way.
For example, in the following abbreviated test HTML:
<span>some text</span>
<script>println("whf")</script>
We would have to craft the expectation file to include the "some text"
segment, usually with some leading whitespace. This is a bit annoying,
and makes it difficult to manually craft expectation files.
So instead of comparing the expectation against the entire DOM inner
text, we now send the inner text of just the <pre> element containing
the test output when we invoke `internals.signalTextTestIsDone`.
CSS Fonts level 4 renames font-stretch to font-width, with font-stretch
being left as a legacy alias. Unfortunately the other specs have not yet
been updated, so both terms are used in different places.
When a property is a "legacy name alias", any time it is used in CSS or
via the CSSOM its aliased name is used instead.
(See https://drafts.csswg.org/css-cascade-5/#legacy-name-alias)
This means we only care about the alias when parsing a string as a
PropertyID - and we can just return the PropertyID it is an alias for.
No need for a distinct PropertyID for it, and no need for LibWeb to
care about it at all.
Previously, we had a bunch of these properties, which misused our code
for "logical aliases", some of which I've discovered were not even
fully implemented. But with this change, all that code can go away, and
making a legacy alias is just a case of putting it in the JSON. This
also shrinks `StyleProperties` as it doesn't need to contain data for
these aliases, and removes a whole load of `-webkit-*` spam from the
style inspector.
`revert` is supposed to revert to the previous cascade origin, but we
previously had it reverting to the previous layer. To support both,
track them separately during the cascade.
As part of this, we make `set_property_expanding_shorthands()` fall back
to `initial` if it can't find a previous value to revert to. Previously
we would just shrug and do nothing if that happened, which only works
if the value you want to revert to is whatever is currently in `style`.
That's no longer the case, because `revert` should skip over any layer
styles that have been applied since the previous origin.
We now expand shorthands into their respective longhand values when
assigning to a shorthand named property on a CSSStyleDeclaration.
We also make sure that shorthands can be round-tripped by correctly
routing named property access through the getPropertyValue() AO,
and expanding it to handle shorthands as well.
A lot of WPT tests for CSS parsing rely on these mechanisms and should
now start working. :^)
Note that multi-level recursive shorthands like `border` don't work
100% correctly yet. We're going to need a bunch more logic to properly
serialize e.g `border-width` or `border` itself.
Previously, attempting to get the computed value for a
grid-template-rows or grid-template-columns property would cause a crash
if the element had no associated paintable.
