From 496db17c2d39e0155a26293d8a628e3a07a5eb83 Mon Sep 17 00:00:00 2001
From: Sam Atkins <atkinssj@serenityos.org>
Date: Mon, 31 Jul 2023 19:48:50 +0100
Subject: [PATCH] LibWeb: Add callback for when a CSSRuleList's rules change

---
 Userland/Libraries/LibWeb/CSS/CSSRuleList.cpp | 4 ++++
 Userland/Libraries/LibWeb/CSS/CSSRuleList.h   | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/Userland/Libraries/LibWeb/CSS/CSSRuleList.cpp b/Userland/Libraries/LibWeb/CSS/CSSRuleList.cpp
index 93a8dbdfdf..49a4cfe8ad 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSRuleList.cpp
+++ b/Userland/Libraries/LibWeb/CSS/CSSRuleList.cpp
@@ -93,6 +93,8 @@ WebIDL::ExceptionOr<unsigned> CSSRuleList::insert_a_css_rule(Variant<StringView,
     m_rules.insert(index, *new_rule);
 
     // 8. Return index.
+    if (on_change)
+        on_change();
     return index;
 }
 
@@ -118,6 +120,8 @@ WebIDL::ExceptionOr<void> CSSRuleList::remove_a_css_rule(u32 index)
     old_rule.set_parent_rule(nullptr);
     old_rule.set_parent_style_sheet(nullptr);
 
+    if (on_change)
+        on_change();
     return {};
 }
 
diff --git a/Userland/Libraries/LibWeb/CSS/CSSRuleList.h b/Userland/Libraries/LibWeb/CSS/CSSRuleList.h
index 199adfc085..395c439e20 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSRuleList.h
+++ b/Userland/Libraries/LibWeb/CSS/CSSRuleList.h
@@ -61,6 +61,8 @@ public:
     bool evaluate_media_queries(HTML::Window const&);
     void for_each_effective_keyframes_at_rule(Function<void(CSSKeyframesRule const&)> const& callback) const;
 
+    Function<void()> on_change;
+
 private:
     explicit CSSRuleList(JS::Realm&);