From d8188c9f14165fa2f2a60ff1bfd569ac3dc61bbb Mon Sep 17 00:00:00 2001
From: Andreas Kling <andreas@ladybird.org>
Date: Fri, 18 Apr 2025 10:31:28 +0200
Subject: [PATCH] LibJS+LibWeb: Add JS::Object::fast_is<T> helpers for some
 LibWeb types

These are slightly unfortunate as we're crossing the library boundary,
but there's precedent with Object::is_dom_node(), and these are just
knocking down a few more items that were showing up in profiles.
---
 Libraries/LibJS/Runtime/Object.h    | 5 +++++
 Libraries/LibWeb/DOM/Event.h        | 5 +++++
 Libraries/LibWeb/HTML/Location.h    | 5 +++++
 Libraries/LibWeb/HTML/Window.h      | 5 +++++
 Libraries/LibWeb/HTML/WindowProxy.h | 4 ++++
 5 files changed, 24 insertions(+)

diff --git a/Libraries/LibJS/Runtime/Object.h b/Libraries/LibJS/Runtime/Object.h
index ba41d0a351f..fb8b03dd03b 100644
--- a/Libraries/LibJS/Runtime/Object.h
+++ b/Libraries/LibJS/Runtime/Object.h
@@ -190,6 +190,11 @@ public:
     void define_native_accessor(Realm&, PropertyKey const&, ESCAPING Function<ThrowCompletionOr<Value>(VM&)> getter, ESCAPING Function<ThrowCompletionOr<Value>(VM&)> setter, PropertyAttributes attributes);
 
     virtual bool is_dom_node() const { return false; }
+    virtual bool is_dom_event() const { return false; }
+    virtual bool is_html_window() const { return false; }
+    virtual bool is_html_window_proxy() const { return false; }
+    virtual bool is_html_location() const { return false; }
+
     virtual bool is_function() const { return false; }
     virtual bool is_promise() const { return false; }
     virtual bool is_error() const { return false; }
diff --git a/Libraries/LibWeb/DOM/Event.h b/Libraries/LibWeb/DOM/Event.h
index 20a42718274..60a16076e88 100644
--- a/Libraries/LibWeb/DOM/Event.h
+++ b/Libraries/LibWeb/DOM/Event.h
@@ -159,6 +159,8 @@ protected:
     virtual void visit_edges(Visitor&) override;
 
 private:
+    virtual bool is_dom_event() const final { return true; }
+
     FlyString m_type;
     GC::Ptr<EventTarget> m_target;
     GC::Ptr<EventTarget> m_related_target;
@@ -188,3 +190,6 @@ private:
 };
 
 }
+
+template<>
+inline bool JS::Object::fast_is<Web::DOM::Event>() const { return is_dom_event(); }
diff --git a/Libraries/LibWeb/HTML/Location.h b/Libraries/LibWeb/HTML/Location.h
index 44a4f486965..07a2ebcfd66 100644
--- a/Libraries/LibWeb/HTML/Location.h
+++ b/Libraries/LibWeb/HTML/Location.h
@@ -71,6 +71,8 @@ public:
 private:
     explicit Location(JS::Realm&);
 
+    virtual bool is_html_location() const override { return true; }
+
     virtual void initialize(JS::Realm&) override;
     virtual void visit_edges(Cell::Visitor&) override;
 
@@ -86,3 +88,6 @@ private:
 };
 
 }
+
+template<>
+inline bool JS::Object::fast_is<Web::HTML::Location>() const { return is_html_location(); }
diff --git a/Libraries/LibWeb/HTML/Window.h b/Libraries/LibWeb/HTML/Window.h
index 6a2429ec349..e0b76d7f00e 100644
--- a/Libraries/LibWeb/HTML/Window.h
+++ b/Libraries/LibWeb/HTML/Window.h
@@ -274,6 +274,8 @@ private:
     virtual void visit_edges(Cell::Visitor&) override;
     virtual void finalize() override;
 
+    virtual bool is_html_window() const override { return true; }
+
     // ^HTML::GlobalEventHandlers
     virtual GC::Ptr<DOM::EventTarget> global_event_handlers_to_event_target(FlyString const&) override { return *this; }
 
@@ -356,3 +358,6 @@ private:
 void run_animation_frame_callbacks(DOM::Document&, double now);
 
 }
+
+template<>
+inline bool JS::Object::fast_is<Web::HTML::Window>() const { return is_html_window(); }
diff --git a/Libraries/LibWeb/HTML/WindowProxy.h b/Libraries/LibWeb/HTML/WindowProxy.h
index 562f6b9404a..6d813c28e4a 100644
--- a/Libraries/LibWeb/HTML/WindowProxy.h
+++ b/Libraries/LibWeb/HTML/WindowProxy.h
@@ -40,6 +40,7 @@ public:
 private:
     explicit WindowProxy(JS::Realm&);
 
+    virtual bool is_html_window_proxy() const override { return true; }
     virtual void visit_edges(JS::Cell::Visitor&) override;
 
     // [[Window]], https://html.spec.whatwg.org/multipage/window-object.html#concept-windowproxy-window
@@ -47,3 +48,6 @@ private:
 };
 
 }
+
+template<>
+inline bool JS::Object::fast_is<Web::HTML::WindowProxy>() const { return is_html_window_proxy(); }