From 021e3f5c7d2ec6aa648451c7aba7c5e14de916cc Mon Sep 17 00:00:00 2001
From: Sam Atkins <sam@ladybird.org>
Date: Wed, 19 Mar 2025 15:19:00 +0000
Subject: [PATCH] LibWeb/CSS: Generate is_has_allowed_pseudo_element()

---
 Libraries/LibWeb/CSS/Selector.cpp             |  7 -----
 Libraries/LibWeb/CSS/Selector.h               |  2 --
 .../LibWeb/GenerateCSSPseudoElement.cpp       | 27 +++++++++++++++++++
 3 files changed, 27 insertions(+), 9 deletions(-)

diff --git a/Libraries/LibWeb/CSS/Selector.cpp b/Libraries/LibWeb/CSS/Selector.cpp
index 563af96677c..2e095ef77da 100644
--- a/Libraries/LibWeb/CSS/Selector.cpp
+++ b/Libraries/LibWeb/CSS/Selector.cpp
@@ -759,11 +759,4 @@ SelectorList adapt_nested_relative_selector_list(SelectorList const& selectors)
     return new_list;
 }
 
-// https://drafts.csswg.org/selectors/#has-allowed-pseudo-element
-bool is_has_allowed_pseudo_element(PseudoElement)
-{
-    // No spec currently defines any pseudo-elements that are allowed in :has()
-    return false;
-}
-
 }
diff --git a/Libraries/LibWeb/CSS/Selector.h b/Libraries/LibWeb/CSS/Selector.h
index 0effa56ec85..8679aa33331 100644
--- a/Libraries/LibWeb/CSS/Selector.h
+++ b/Libraries/LibWeb/CSS/Selector.h
@@ -264,8 +264,6 @@ String serialize_a_group_of_selectors(SelectorList const& selectors);
 
 SelectorList adapt_nested_relative_selector_list(SelectorList const&);
 
-bool is_has_allowed_pseudo_element(PseudoElement);
-
 }
 
 namespace AK {
diff --git a/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSPseudoElement.cpp b/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSPseudoElement.cpp
index ce630d9b147..cbcb7e1923d 100644
--- a/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSPseudoElement.cpp
+++ b/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSPseudoElement.cpp
@@ -72,6 +72,8 @@ enum class PseudoElement : @pseudo_element_underlying_type@ {
 Optional<PseudoElement> pseudo_element_from_string(StringView);
 StringView pseudo_element_name(PseudoElement);
 
+bool is_has_allowed_pseudo_element(PseudoElement);
+
 }
 )~~~");
 
@@ -133,6 +135,31 @@ StringView pseudo_element_name(PseudoElement pseudo_element)
     VERIFY_NOT_REACHED();
 }
 
+bool is_has_allowed_pseudo_element(PseudoElement pseudo_element)
+{
+    switch (pseudo_element) {
+)~~~");
+
+    pseudo_elements_data.for_each_member([&](auto& name, JsonValue const& value) {
+        auto& pseudo_element = value.as_object();
+        if (!pseudo_element.get_bool("is-allowed-in-has"sv).value_or(false))
+            return;
+
+        auto member_generator = generator.fork();
+        member_generator.set("name:titlecase", title_casify(name));
+
+        member_generator.append(R"~~~(
+    case PseudoElement::@name:titlecase@:
+        return true;
+)~~~");
+    });
+
+    generator.append(R"~~~(
+    default:
+        return false;
+    }
+}
+
 }
 )~~~");