From a2c9ab9c9ac938e54eee338813ac850aa84fe1e0 Mon Sep 17 00:00:00 2001
From: Callum Law <callumlaw1709@outlook.com>
Date: Thu, 21 Aug 2025 16:38:17 +1200
Subject: [PATCH] LibWeb: Return `AbstractElement` from
 `element_to_inherit_style_from`

No functional changes.
---
 Libraries/LibWeb/CSS/StyleComputer.cpp   | 5 +++--
 Libraries/LibWeb/DOM/AbstractElement.cpp | 9 +++++++--
 Libraries/LibWeb/DOM/AbstractElement.h   | 2 +-
 3 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/Libraries/LibWeb/CSS/StyleComputer.cpp b/Libraries/LibWeb/CSS/StyleComputer.cpp
index b447809d809..50d054be9a6 100644
--- a/Libraries/LibWeb/CSS/StyleComputer.cpp
+++ b/Libraries/LibWeb/CSS/StyleComputer.cpp
@@ -3119,9 +3119,10 @@ NonnullRefPtr<StyleValue const> StyleComputer::compute_value_of_custom_property(
     // Unset is the same as inherit for inherited properties, and by default all custom properties are inherited.
     // FIXME: Support non-inherited registered custom properties.
     if (value->is_inherit() || value->is_unset()) {
-        if (!abstract_element.element_to_inherit_style_from())
+        auto element_to_inherit_style_from = abstract_element.element_to_inherit_style_from();
+        if (!element_to_inherit_style_from.has_value())
             return document.custom_property_initial_value(name);
-        auto inherited_value = DOM::AbstractElement { const_cast<DOM::Element&>(*abstract_element.element_to_inherit_style_from()) }.get_custom_property(name);
+        auto inherited_value = element_to_inherit_style_from->get_custom_property(name);
         if (!inherited_value)
             return document.custom_property_initial_value(name);
         return inherited_value.release_nonnull();
diff --git a/Libraries/LibWeb/DOM/AbstractElement.cpp b/Libraries/LibWeb/DOM/AbstractElement.cpp
index f07fb274c70..e66ba5015ba 100644
--- a/Libraries/LibWeb/DOM/AbstractElement.cpp
+++ b/Libraries/LibWeb/DOM/AbstractElement.cpp
@@ -40,9 +40,14 @@ GC::Ptr<Element const> AbstractElement::parent_element() const
     return m_element->parent_element();
 }
 
-GC::Ptr<Element const> AbstractElement::element_to_inherit_style_from() const
+Optional<AbstractElement> AbstractElement::element_to_inherit_style_from() const
 {
-    return m_element->element_to_inherit_style_from(m_pseudo_element);
+    GC::Ptr<Element const> element = m_element->element_to_inherit_style_from(m_pseudo_element);
+
+    if (!element)
+        return OptionalNone {};
+
+    return AbstractElement { const_cast<DOM::Element&>(*element) };
 }
 
 Optional<AbstractElement> AbstractElement::walk_layout_tree(WalkMethod walk_method)
diff --git a/Libraries/LibWeb/DOM/AbstractElement.h b/Libraries/LibWeb/DOM/AbstractElement.h
index af44dab2579..5cc885ff50b 100644
--- a/Libraries/LibWeb/DOM/AbstractElement.h
+++ b/Libraries/LibWeb/DOM/AbstractElement.h
@@ -27,7 +27,7 @@ public:
     GC::Ptr<Layout::NodeWithStyle const> layout_node() const { return const_cast<AbstractElement*>(this)->layout_node(); }
 
     GC::Ptr<Element const> parent_element() const;
-    GC::Ptr<Element const> element_to_inherit_style_from() const;
+    Optional<AbstractElement> element_to_inherit_style_from() const;
     Optional<AbstractElement> previous_in_tree_order() { return walk_layout_tree(WalkMethod::Previous); }
     Optional<AbstractElement> previous_sibling_in_tree_order() { return walk_layout_tree(WalkMethod::PreviousSibling); }
     bool is_before(AbstractElement const&) const;