LibWeb: Implement the :where() selector

This is identical to :is() except for specificity, so we can use the
same code paths. :^)

1 files changed, 4 insertions, 2 deletions

diff --git a/Userland/Libraries/LibWeb/CSS/Selector.cpp b/Userland/Libraries/LibWeb/CSS/Selector.cpp
index 85dc1a3b07..24e7ed97c8 100644
--- a/Userland/Libraries/LibWeb/CSS/Selector.cpp
+++ b/Userland/Libraries/LibWeb/CSS/Selector.cpp
@@ -159,6 +159,7 @@ String Selector::SimpleSelector::serialize() const
         case Selector::SimpleSelector::PseudoClass::Type::NthLastChild:
         case Selector::SimpleSelector::PseudoClass::Type::Not:
         case Selector::SimpleSelector::PseudoClass::Type::Is:
+        case Selector::SimpleSelector::PseudoClass::Type::Where:
             // Otherwise, append ":" (U+003A), followed by the name of the pseudo-class, followed by "(" (U+0028),
             // followed by the value of the pseudo-class argument(s) determined as per below, followed by ")" (U+0029), to s.
             s.append(':');
@@ -169,9 +170,10 @@ String Selector::SimpleSelector::serialize() const
                 // The result of serializing the value using the rules to serialize an <an+b> value.
                 s.append(pseudo_class.nth_child_pattern.serialize());
             } else if (pseudo_class.type == Selector::SimpleSelector::PseudoClass::Type::Not
-                || pseudo_class.type == Selector::SimpleSelector::PseudoClass::Type::Is) {
+                || pseudo_class.type == Selector::SimpleSelector::PseudoClass::Type::Is
+                || pseudo_class.type == Selector::SimpleSelector::PseudoClass::Type::Where) {
                 // The result of serializing the value using the rules for serializing a group of selectors.
-                // NOTE: `:is()` isn't in the spec for this yet, but it should be!
+                // NOTE: `:is()` and `:where()` aren't in the spec for this yet, but it should be!
                 s.append(serialize_a_group_of_selectors(pseudo_class.argument_selector_list));
             }
             s.append(')');