When serializing CSS declarations we now support combining multiple
properties into a single shorthand property in some cases.
This comes with a healthy dose of FIXMEs, including work to be done
around supporting:
- Nested shorthands (e.g. background, border, etc)
- Shorthands which aren't represented by the ShorthandStyleValue type
- Subproperties pending substitution
This gains us a bunch of new test passes, both for WPT and in-tree
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.
If a calculation was simplified down to a single numeric node, then most
of the time we can instead return a regular StyleValue, for example
`calc(2px + 3px)` would be simplified down to a `5px` LengthStyleValue.
This means that parse_calculated_value() can't return a
CalculatedStyleValue directly, and its callers all have to handle
non-calculated values as well as calculated ones.
This simplification is reflected in the new test results. Serialization
is not yet correct in all cases but we're closer than we were. :^)
This allows us to disable test output, which performs expensive assert
tracking. This was making our imported tests run significantly slower
than tests run via `WPT.sh`.
Formatting the output ourselves also allows us to remove unnecessary
information from the test output.
This commit also rebaselines all existing imported WPT tests to follow
the new format.
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.
