This fixes an issue where we'd serialize some floating point numbers
with excessive precision, resulting in unpleasant-looking numbers like
0.49999999999999999 and such.
At least 90 new subtests passing on WPT, possibly more. :^)
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!
Some dimensions would always serialize in a canonical unit, others never
did, and others we manually would do so in their StyleValue. This
commit moves all of that into the dimension types, which means for
example that Length can apply its special rounding.
Our local serialization test now produces the same output as other
browsers. :^)
Selector::serialize() is used for both normal and relative selectors.
For the latter, we need to serialize their initial combinator, and for
the former, we always set the initial combinator as None anyway, so
this would be a no-op there.
Gets us 3 WPT passes.
The spec requires us to accept any ident here, not just ltr/rtl, and
also serialize it back out. That means we need to keep the original
string around.
In order to not call keyword_from_string() every time we want to match
a :dir() selector, we still attempt to parse the keyword and keep it
around.
A small behaviour change is that now we'll serialize the ident with its
original casing, instead of always lowercase. Chrome and Firefox
disagree on this, so I think either is fine until that can be
officially decided.
Gets us 2 WPT passes (including 1 from the as-yet-unmerged :dir() test).
The spec gives us a hard-coded list of functional pseudo-classes and how
to serialize them - but this list is incomplete and likely to always be
outdated compared to the list of pseudo-classes that exist. So instead,
use the generated metadata we already have to serialize their arguments
based on their type.
This fixes :dir() and :has(), which previously did not serialize their
arguments.
Gets us 26 passes (including 6 from that as-yet-unmerged :dir() test).
The main motivation here is that the CSS Parser needs to know about
PageSelectorList so that we can parse one in
`CSSPageRule::set_selector_text()`. Including all of `CSSPageRule.h`
there would pull in a lot of other headers that aren't needed.
Previously we only matched against the first attribute with a given
local name. What we actually want to do is look at each attribute with
that local name in turn and only return false if none of them match.
Also remove a hack for HTML elements in HTML documents, where we would
refuse to match any namespaced attributes. This doesn't seem to be
based on the spec, but we had regressions without it, until now. :^)
Gets us 21 more WPT subtest passes.
The HTML spec gives us a list of HTML attributes that must have their
values compared case-insensitively by default (when the attribute
selector does not specify a case-sensitiveness). However, ifwe have a
namespace, then we are not looking for an HTML attribute, so this
should not apply.
Gets us 8 more WPT subtest passes.
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.
With this, we pass the 8 ref tests in css/selectors/selectors-4/ which
previously failed. This is not technically a full implementation, as we
are supposed to first canonicalize the language range and tag, but that
will require downloading and processing the IANA language subtag
registry:
https://www.iana.org/assignments/language-subtag-registry/language-subtag-registry
That's significantly more work, and WPT doesn't seem to test any cases
that require that, so we can leave it for now.
I was wrong when I added those notes before about this being impossible,
it's *very* possible, for example with the `@page margin` descriptor.
However, until we have a large number of these shorthands and not just a
single example, we can get away with hard-coding support for it.
Ideally we'd be able to share the code between page selectors and style
ones, but given how simple page selectors are, some code duplication is
the simpler option.
Previously, we would just assign the UnresolvedStyleValue to each
longhand, which was completely wrong but happened to work if it was a
ShorthandStyleValue (because that's basically a list of "set property X
to Y", and doesn't care which property it's the value of).
For example, the included `var-in-margin-shorthand.html` test would:
1. Set `margin-top` to `var(--a) 10px`
2. Resolve it to `margin-top: 5px 10px`
3. Reject that as invalid
What now happens is:
1. Set `margin-top` to a PendingSubstitutionValue
2. Resolve `margin` to `5px 10px`
3. Expand that out into its longhands
4. `margin-top` is `5px` 🎉
In order to support this, `for_each_property_expanding_shorthands()` now
runs the callback for the shorthand too if it's an unresolved or
pending-substitution value. This is so that we can store those in the
CascadedProperties until they can be resolved - otherwise, by the time
we want to resolve them, we don't have them any more.
`cascade_declarations()` has an unfortunate hack: it tracks, for each
declaration, which properties have already been given values, so that
it can avoid overwriting an actual value with a pending one. This is
necessary because of the unfortunate way that CSSStyleProperties holds
expanded longhands, and not just the original declarations. The spec
disagrees with itself about this, but we do need to do that expansion
for `element.style` to work correctly. This HashTable is unfortunate
but it does solve the problem until a better solution can be found.
If `value` was UnresolvedStyleValue, we'd attempt to `set_property...()`
with its resolved value, then call that again with the original
UnresolvedStyleValue. For any other kind of `value`, we'd simply call
call `set_property...()` twice with the same parameters.
This holds the boilerplate that's needed by any CSSStyleDeclaration
subclass that holds Descriptors. CSSFontFaceDescriptors now only has to
worry about initialization and its own exposed properties.
After f7a3f785a8, sibling nodes' styles
were no longer invalidated after a node was removed. This reuses the
flag for `:first-child` and `:last-child` to indicate that a node's
style might be affected by any structural change in its siblings.
Fixes#4631.
Resolves the `:only-child` ACID3 failure as documented in #1231.
Similar to other ad-hoc behavior in this method, we need to handle
requests which are not associated with a style sheet. For example:
<script>
const element = document.createElement('div');
element.style['background'] = 'url(https://foo.com/img.png)';
document.body.appendChild(element);
</script>
Will not be associated with a style sheet.
This is needed to ensure we fire a PerformanceResourceTiming event for
this resource load. This is not currently testable in CI, as this event
is also gated by HTTP/S requests.
Browsers such as Chrome and Firefox apply an arbitrary scale to the
current font size if `normal` is used for `line-height`. Firefox uses
1.2 while Chrome uses 1.15. Let's go with the latter for now, it's
relatively easy to change if we ever want to go back on that decision.
This also requires updating the expectations for a lot of layout tests.
The upside of this is that it's a bit easier to compare our layout
results to other browsers', especially Chrome.
