Andreas Kling 9fae2bcff9 LibWeb: Avoid unrelated structural :has invalidation ...

Track the simple selector features that appear inside :has() arguments
on each StyleScope, then consult that metadata before scheduling an
ancestor walk for a structural mutation. If the mutated subtree has no
tag, id, class, attribute, or pseudo-class feature that any cached
:has() argument cares about, skip the walk entirely.

Stay conservative for featureless-sensitive arguments such as :has(*),
:has(:not(...)), :has(:empty), and child-index pseudos: an unfeatured
node can still start or stop matching there. Track that case via a new
has_selectors_sensitive_to_featureless_subtree_changes flag on
StyleInvalidationData and fall back to the old conservative walk.

Stay conservative for pseudo-classes the subtree filter cannot probe
(:focus, :hover, validation pseudos). Move :default out of the set of
trackable feature pseudo-classes for the same reason; it now triggers
the conservative walk where it previously recorded metadata.

Tag and attribute names are stored lowercased, so for non-HTML elements
(SVG, MathML) treat lowercased matches as scheduling hints only; the
actual :has() match still goes through case-sensitive selector matching.

Test counter expectations are rebaselined to reflect the skipped walks
and reduced recomputations. Matching behavior is unchanged.

2026-04-28 15:34:49 +02:00

2.8 KiB

Raw Blame History

View Raw