Currently this only applies to the `@property` `syntax` descriptor.
As with custom properties in the previous commit we assumed that any
consumed values were valid but that's not the case.
The definition of syntax in the "css-properties-values-api" spec (which
is used for the `@property/syntax` descriptor) is slightly different
from the definition of `<syntax>` in the "css-values" spec (which we
implement) in that it limits literal idents to exclusively
`<custom-ident>`s (i.e. not CSS-wide keywords or "default").
`<custom-ident>`s are also case-sensitive so that behavior is
implemented for syntax matching here as well
Previously we would consider an alternative syntax child to be a match
as long as parsing produced a value, even if there were trailing tokens
(which would later invalidate it within `parse_with_a_syntax`). This
meant that we wouldn't consider later alternatives which may actually
produce a valid match.
We no longer try to resolve calculated values at parse time which means
we support relative lengths.
We now clamp negative values rather than rejecting them at parse time.
Parsing has been inlined into `parse_ratio_value` and `parse_ratio` has
been removed since `parse_ratio_value` was the only caller
When parsing block contents, the CSS parser speculatively tries to parse
each item as a declaration first. If that fails, it restores the token
position and tries again as a qualified rule. This means every qualified
rule inside an at-rule block (e.g. @layer, @media) gets parsed twice:
once as a failed declaration (which consumes all tokens via
consume_the_remnants_of_a_bad_declaration), and then again successfully
as a rule.
Add a lookahead that checks for the `ident whitespace* ':'` pattern
before attempting declaration parsing. Since declarations must start
with this pattern per spec, we can skip the attempt entirely when it
doesn't match and go straight to qualified rule parsing.
This is a massive win on large Tailwind CSS stylesheets (like the one
used by chatgpt.com) where thousands of rules inside @layer blocks were
being double-parsed. On a 1.2MB Tailwind v4 stylesheet, parse time goes
from ~2000ms to ~95ms (21x speedup).
When a var() fallback value contained trailing whitespace (e.g.
`var(--foo, flex )`), parse_display_value() miscounted the tokens.
The remaining_token_count() check included whitespace tokens, routing
single-keyword values like "flex" to the multi-component path. The
multi-component parser then failed when encountering the trailing
whitespace token.
Fix this by counting only non-whitespace tokens for the single vs
multi-component routing decision, and by skipping whitespace in the
multi-component parsing loop.
See previous commit for details
We now support parsing of `display-p3-linear` (although it just falls
back to using Oklab since Skia doesn't support it)
Previously we had two implementations for parsing
`<color-interpolation-method>`, one for gradients and one for
`color-mix()` - this commit adds another which will unify the existing
ones in following commits.
This implementation has a couple of advantages over the existing ones:
- It is simpler in that it uses global CSS enums and their helper
functions
- It is spec compliant (unlike the `color-mix()` one which allows
arbitrary idents)
- It parses as a `StyleValue` which will be required once we support
`<custom-color-space>` since that can be an `ident()` which isn't
resolvable at parse time
While all parsed argument grammars can be represented as
`Vector<Vector<ComponentValue>>`, we can save some redundant work by
storing them in their argument-grammar-parsed format.
Note that for all currently implemented ASFs this is actually
`Vector<Vector<ComponentValue>>` and thus this change will only be
relevant for ASFs we haven't implemented yet
There are some predefined counter styles (such as the longhand east
asian ones) which are too complex to be defined here and will need to be
implemented ad-hoc, this remains as a FIXME for now.
The CSS content property's alt text (after `/`) was incorrectly
accepting any content value. Per the CSS Content Module Level 3 spec,
alt text only accepts <string>, <counter>, and <attr()> values. This
change adds type validation in the alt text parsing branch to reject
URLs, quote keywords, images, and other non-alt-text value types.
This fixes 64 subtests in the content-invalid WPT test.
Move grid area rectangle computation and validation from layout to the
CSS parser. Named grid areas that don't form filled-in rectangles now
correctly invalidate the declaration per spec.
The grammar groups this component together meaning that all
sub-components must occur together i.e.
`ordinal slashed-zero small-caps` is valid but
`ordinal small-caps slashed-zero` is not.
We also reuse the logic for parsing from the longhand
`font-variant-numeric` property for simplicity.
The grammar groups this component together meaning that all
sub-components must occur together i.e.
`common-ligatures no-contextual small-caps` is valid but
`common-ligatures small-caps no-contextual` is not.
We also reuse the logic for parsing from the longhand
`font-variant-ligatures` property for simplicity.
The grammar groups this component together meaning that all
sub-components must occur together i.e. `jis78 full-width small-caps` is
valid but `jis78 small-caps full-width` is not.
We also reuse the logic for parsing from the longhand
`font-variant-east-asian` property for simplicity.