`font-weight` and `font-size` both can have keywords that are relative
to their inherited value, and so need recomputing when that changes.
Fixes all but one subtest in font-weight-computed.html, because that
remaining one uses container-query units. No font-size tests seem to be
affected: font-size-computed.html doesn't update the parent element's
`font-size` so this invalidation bug didn't apply.
The rules for strings here are:
- 4 ASCII characters long
- Shorter ones are right-padded with spaces before use
- Trailing whitespace is always removed when serializing
We previously always padded them during parsing, which was incorrect.
This commit flips it around so we trim trailing whitespace when parsing.
We don't yet actually use this property's value for anything. Once we do
so, maybe we'll care more about them being stored as 4 characters
always, but for now this avoids us needing a special step during
computation.
Adds support for `sibling-index()` and `sibling-count()` when parsing
`<number>` and `<integer>`. This is achieved by a new
`TreeCountingFunctionStyleValue` class which is converted within
`absolutized` to `NumberStyleValue` and `IntegerStyleValue` respectively
There are still a few kinks to work out in order to support these
everywhere, namely:
- There are some `StyleValue`s which aren't absolutized (i.e. those
which are stored within another `StyleValue` without an
`absolutize()` method.
- We don't have a way to represent this new `StyleValue` within
`{Number,Integer}OrCalculated`. This would be fixed if we were to
instead just use the `StyleValue` classes until style computation at
which time they would be absolutized into their respective
primitives (double, i64, etc) bypassing the need for *OrCalculated
entirely.
This change adds the allowed angle range to the `font-style` property
definition. This allows these angles to be clamped after interpolation.
Ideally, the generator should be updated so that we can specify the
angle is in degrees. This would allow us to make use of this
information during parsing, which we can't do currently because we
don't know what the unit is. Using this value for interpolation
purposes is fine because the angle has been converted to its canonical
unit by this point.
We now also more closely follow the spec when computing values for
font-weight and we now:
- Support relative lengths in `calc()`s
- Properly clamp `calc()`s
- Support relative keywords (e.g. lighter, bolder)
- Respect that font-weight can be a non-integer number.
This does expose a few false positives in the font-weight-computed.html
WPT test. This is because we don't recompute non-inherited font-weight
within `recompute_inherited_style` which means that relative keyword
values can fall out of sync with their parent's value. These previously
passed as we treated `bolder` and `lighter` as aliases for `bold` and
`normal` respectively.
Remaining test failures in font-size-interpolation-00* are either:
- Rounding of font-size to CSSPixels when setting the expected value
- Not clamping negative values from the point of view of
getComputedStyle (used values are still clamped)
Previously if we would overwrite the non-animated font-size with the
animated font-size if it was set.
Gains us 8 WPT tests and means we now fail 9 others in line with other
browsers.
`font-size` can end up with a negative value - either due to `calc`
being resolved using the old method which doesn't clamp the value, or
interpolation - in this case we should clamp negative values to zero.
Gains us 36 new WPT passes and fixes crashes in the three imported
tests.
We now clamp the values returned from calc into the allowed range (where
we know it) and censor any `NaN`s to `0` both when we resolve and when
we serialize.
Gains us 76 WPT passes.
Based very scientifically on what's listed here:
https://harfbuzz.github.io/what-does-harfbuzz-do.html
I've moved the code into LibGfx because including a HarfBuzz header
directly from LibWeb is a little unpleasant. But the Gfx::FontTech enum
follows the CSS definitions for font features for simplicity.
TrueType collections are supported. SVG and Embedded OpenType are not,
but they're not widely supported by other browsers so that's fine.
Most of the features are completely supported by HarfBuzz, so we can
just return true. Graphite support is optional (and it appears we use a
build of HarfBuzz without it) but there's a define we can check.
Incremental Font Transfer is a whole separate thing that we definitely
don't support yet.
This function attempts to resolve `lighter` and `bolder`, which we don't
want to do when serializing - that should happen in style computation.
This has the unexpected bonus of 37 more WPT passes!
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. :^)
We don't want to reset the values of `font-variant-*` here, as that will
override whatever our parsed font-variant-css2 was, so stop doing that.
Also, font-stretch is mentioned in the spec, but it's a legacy name
alias for font-width, so we don't need to do anything for it.
Gets us 319 WPT passes!
"format(woff-variations)" and pals are supposed to expand like so:
"format(woff) tech(variations)".
However, since we don't support tech() yet, this patch just adds a small
hack where we still treat "woff-variations" as "woff" so that fonts
load and get used, even if we don't make use of the variations yet.
This gives us a more human-looking serialization of numbers by default,
and in case a fixed number of decimal digits is actually wanted, we
still have the 'f' specifier.
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 commit disallows "default" as a font-family name, when the name is
not quoted because unquoted names are treated as custom-idents, for
which the name "default" is not allowed.
CSSFontFaceRule now stores its values as a CSSFontFaceDescriptors, with
a ParsedFontFace produced on request. This is exposed via the `style`
attribute, so we pass a lot of tests that try to read values from
that.
We have one test regression, which we passed by mistake before: The test
wanted to ensure we don't allow `@font-face` nested inside other rules.
We passed it just because we discarded any `@font-face` without a
`font-family`. What we're supposed to do is 1) keep at-rules with
missing required descriptors and just not use them, and 2) reject
certain ones when nested.
We may want to cache the ParsedFontFace in the future, but I didn't here
because 1) it's called rarely, and 2) that would mean knowing to
invalidate it when the CSSFontFaceDescriptors changes, which isn't
obvious to me right now.
This gets us 37 new subtest passes in css/css-values, and 13 passes in
our other in-tree tests (and probably some random other ones!)
As noted in comments, a few parts of this algorithm have ad-hoc
behaviour to handle some issues in the spec.
The spec wants these keywords to appear in a particular order when
serialized, so let's just put them in that order during parsing.
This also fixes a bug where we didn't reject `font-variant-east-asian`
that contains `normal` alongside another value.
Also, rather than always parsing them as a StyleValueList, parse single
values on their own, and then support that in the to_font_variant_foo()
methods.
Without this, we'd happily parse `font-variant-caps: small-caps potato`
as just `small-caps` and ignore the fact that unused tokens were left
over.
This fix gets us some WPT subtest passes, and removes the need for a
bespoke parsing function for font-variant-caps.
