CSS Text 3 gives `text-indent` a couple of optional keywords to control
which lines are affected. This commit parses them, but doesn't yet do
anything with them.
Before this change, we've been maintaining various StyleComputer caches
at the document level.
This made sense for old-school documents without shadow trees, since
all the style information was document-wide anyway. However, documents
with many shadow trees ended up suffering since any time you mutated
a style sheet inside a shadow tree, *all* style caches for the entire
document would get invalidated.
This was particularly expensive on Reddit, which has tons of shadow
trees with their own style elements. Every time we'd create one of their
custom elements, we'd invalidate the document-level "rule cache" and
have to rebuild it, taking about ~60ms each time (ouch).
This commit introduces a new object called StyleScope.
Every Document and ShadowRoot has its own StyleScope. Rule caches etc
are moved from StyleComputer to StyleScope.
Rule cache invalidation now happens at StyleScope level. As an example,
rule cache rebuilds now take ~1ms on Reddit instead of ~60ms.
This is largely a mechanical change, moving things around, but there's
one key detail to be aware of: due to the :host selector, which works
across the shadow DOM boundary and reaches from inside a shadow tree out
into the light tree, there are various places where we have to check
both the shadow tree's StyleScope *and* the document-level StyleScope
in order to get all rules that may apply.
We don't need all this specific logic for parsing the `transition`
property - we also now maintain `none` as such until use time which
gains us a couple extra tests
Passing the `AbstractElement` rather than the
`TreeCountingFunctionResolutionContext` allows us to only compute the
resolution context when necessary (i.e. when we actually need to resolve
a tree counting function)
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.
Tree counting functions should be resolved at style computation time -
to do this we will need to know the element's sibling count and index.
This commit computes that information and propagates it to the various
`StyleValue::to_computed_value` methods.
We often want to call a function with either a built-in or custom
property, and that means either passing it as a string (and converting
back and forth between strings and PropertyIDs) or using the
PropertyIDOrCustomPropertyName variant, which complicates user code.
PropertyNameAndID is intended to make that easier: Create it with a
string or PropertyID, and it can tell you either one.
This is the final CSSStyleValue class used by the per-property test
harness, so those now actually run instead of throwing an exception on
load. 🎉
+39 WPT subtests. (Plus however many from the per-property tests finally
running.)
The two failing serialization tests are also failed by Safari in exactly
the same way, so that seems more like a spec issue. (The spec is
incomplete in quite a few places.) The failing subtest for toMatrix() is
also a spec issue: is2D is handled oddly by CSSMatrixComponent and this
subtest fails because of the `matrix` getter, which is unspecified. See
https://github.com/w3c/css-houdini-drafts/issues/1155 for details.
Equivalent to the perspective() transform function.
+34 WPT subtests, and the transformvalue-normalization test now runs to
completion instead of throwing an error - though its cases still fail
until CSSTransformValue is implemented.
This is a base type for the various transform functions.
CSSMatrixComponent's to_string() can throw exceptions, so to_string() is
implemented that way. https://github.com/w3c/fxtf-drafts/issues/611
+9 WPT subtests.
This introduces the `TextUnderlinePositionStyleValue` class, it is
possible to represent `text-underline-position` as a `StyleValueList`
but would have required ugly workarounds for either serialization or in
`ComputedProperties::text_underline_position`
