Add an abstract image style value for image-set() and parse both the
standard and -webkit-prefixed spellings through the existing <image>
value path. The parser accepts URL and string image candidates,
optional resolution descriptors, and type() filters.
Track attr-taint through substituted component values so image-set()
candidates using attr()-derived URL-producing tokens are rejected when
resolved for URL-using properties.
Update the relevant WPT baselines now that image-set() parsing is
supported in additional value contexts.
Previously we would generate the calculation context based on the
current value parsing context. The main problem with this was that
contexts were defined per property by default and had to be overriden
per component value using "special" contexts, which was easy to forget.
We now generate the calculation context per component value in the
relevant `parse_foo_value` methods.
The new failures in `typed_arithmetic.html` are because we no longer
treat percentages as resolving to their property-level type when
computing what the resolved type of a calculation is i.e. when we are
parsing the `<number>` portion of `line-height` we treat percentages as
raw percentages, not lengths. This brings us in line with WebKit but no
longer with Chrome and WPT, I am not sure what the correct behavior is.
This brings a couple of advantages:
- Previously we relied on the caller validating the parsed value was in
bounds after the fact - this was usually fine but there are a couple
of places that it was forgotten (see the tests added in this commit),
requiring the bounds to be passed as arguments makes us consider the
desired range more explicitly.
- In a future commit we will use the passed bounds as the clamping
bounds for computed values, removing the need for the existing
`ValueParsingContext` based method we have at the moment.
- Generating code is easier with this approach
In a future commit we will use the allowed literal values as the bounds
for calculated values rather than the existing `ValueParsingContext`
based system. Since the computed bounds are different from the allowed
literal values here we need to handle clamping them manually.
This allows us to avoid the ugly hack in
`property_accepted_type_ranges()`.
This also updates the `ValueType` to be `opacity-value` rather than
`opacity` to match the spec.
In a future commit we will be applying clamping to numeric (i.e.
number, percentage, dimension) values which will be done in the
appropriate `Token` getters so accessing the underlying number value
would be a potential footgun
Introduce a descriptor table keyed by `ColorType` that encodes
per-space metadata: channel kind, percent reference value, clamp
bounds, function name and serialization behavior.
This descriptor table is then used so that a single class can back
every CSS color type. Resolution, serialization, and absolutization
are driven by the descriptor.
These are only used at used value time (since we store as `StyleValue`s
before) by which time we resolve all percentages except for layout
relative length percentages.
This spec note reads to me as explicitly disallowing combining
`<length>` and `<flex>` (i.e. `calc(1px + 1fr)`). This behavior is
already implemented (as it is for all other combination of units i.e.
`<length>` and `<time>`).
This simplifies handling (particularly around absolutization and
interpolation) and allows us to support calculated flex values (which
will come in a later commit).
This introduces two new top-level `ValueParsingContext`s,
`OnScreenCanvasContextFontValue` and `CanvasContextGenericValue`, while
these are handled the same for now, there is a distinction is whether or
not they allow tree counting functions (which will come in a later
commit)
This correctly rejects invalid trailing tokens from `anchor()` fallback
values. Also introduces discard_whitespace() to take care of any
whitespace between the fallback value and the closing parenthesis.
There was only one place that we weren't passing this where we could
have ASFs so let's just handle that there and explicitly mark the others
as having no ASFs to avoid unnecessary work.
No functional changes
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
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
