6 files changed, 33 insertions, 39 deletions
diff --git a/Userland/Libraries/LibJS/Runtime/ECMAScriptFunctionObject.cpp b/Userland/Libraries/LibJS/Runtime/ECMAScriptFunctionObject.cpp
index bebb6436bc..2d9f6eef35 100644
--- a/Userland/Libraries/LibJS/Runtime/ECMAScriptFunctionObject.cpp
+++ b/Userland/Libraries/LibJS/Runtime/ECMAScriptFunctionObject.cpp
@@ -100,6 +100,11 @@ void ECMAScriptFunctionObject::visit_edges(Visitor& visitor)
     visitor.visit(m_environment);
     visitor.visit(m_realm);
     visitor.visit(m_home_object);
+
+    for (auto& field : m_fields) {
+        field.name.visit_edges(visitor);
+        visitor.visit(field.initializer);
+    }
 }
 
 FunctionEnvironment* ECMAScriptFunctionObject::create_environment(FunctionObject& function_being_invoked)
@@ -245,4 +250,17 @@ void ECMAScriptFunctionObject::set_name(const FlyString& name)
     VERIFY(success);
 }
 
+// 7.3.31 DefineField ( receiver, fieldRecord ), https://tc39.es/ecma262/#sec-definefield
+void ECMAScriptFunctionObject::InstanceField::define_field(VM& vm, Object& receiver) const
+{
+    Value init_value = js_undefined();
+    if (initializer) {
+        auto init_value_or_error = vm.call(*initializer, receiver.value_of());
+        if (init_value_or_error.is_error())
+            return;
+        init_value = init_value_or_error.release_value();
+    }
+    receiver.create_data_property_or_throw(name, init_value);
+}
+
 }
diff --git a/Userland/Libraries/LibJS/Runtime/ECMAScriptFunctionObject.h b/Userland/Libraries/LibJS/Runtime/ECMAScriptFunctionObject.h
index 5dd9fd5d1f..a620e67aa7 100644
--- a/Userland/Libraries/LibJS/Runtime/ECMAScriptFunctionObject.h
+++ b/Userland/Libraries/LibJS/Runtime/ECMAScriptFunctionObject.h
@@ -58,6 +58,16 @@ public:
     Object* home_object() const { return m_home_object; }
     void set_home_object(Object* home_object) { m_home_object = home_object; }
 
+    struct InstanceField {
+        StringOrSymbol name;
+        ECMAScriptFunctionObject* initializer { nullptr };
+
+        void define_field(VM& vm, Object& receiver) const;
+    };
+
+    Vector<InstanceField> const& fields() const { return m_fields; }
+    void add_field(StringOrSymbol property_key, ECMAScriptFunctionObject* initializer) { m_fields.empend(property_key, initializer); }
+
 protected:
     virtual bool is_strict_mode() const final { return m_strict; }
 
@@ -77,6 +87,7 @@ private:
     ThisMode m_this_mode { ThisMode::Global };                    // [[ThisMode]]
     bool m_strict { false };                                      // [[Strict]]
     Object* m_home_object { nullptr };                            // [[HomeObject]]
+    Vector<InstanceField> m_fields;                               // [[Fields]]
     bool m_is_class_constructor { false };                        // [[IsClassConstructor]]
 
     FlyString m_name;
diff --git a/Userland/Libraries/LibJS/Runtime/FunctionObject.cpp b/Userland/Libraries/LibJS/Runtime/FunctionObject.cpp
index 0bc775a0ca..3004a004e2 100644
--- a/Userland/Libraries/LibJS/Runtime/FunctionObject.cpp
+++ b/Userland/Libraries/LibJS/Runtime/FunctionObject.cpp
@@ -66,24 +66,6 @@ BoundFunction* FunctionObject::bind(Value bound_this_value, Vector<Value> argume
     return heap().allocate<BoundFunction>(global_object(), global_object(), target_function, bound_this_object, move(all_bound_arguments), computed_length, constructor_prototype);
 }
 
-void FunctionObject::add_field(StringOrSymbol property_key, FunctionObject* initializer)
-{
-    m_fields.empend(property_key, initializer);
-}
-
-// 7.3.31 DefineField ( receiver, fieldRecord ), https://tc39.es/ecma262/#sec-definefield
-void FunctionObject::InstanceField::define_field(VM& vm, Object& receiver) const
-{
-    Value init_value = js_undefined();
-    if (initializer) {
-        auto init_value_or_error = vm.call(*initializer, receiver.value_of());
-        if (init_value_or_error.is_error())
-            return;
-        init_value = init_value_or_error.release_value();
-    }
-    receiver.create_data_property_or_throw(name, init_value);
-}
-
 void FunctionObject::visit_edges(Visitor& visitor)
 {
     Base::visit_edges(visitor);
@@ -92,11 +74,6 @@ void FunctionObject::visit_edges(Visitor& visitor)
 
     for (auto argument : m_bound_arguments)
         visitor.visit(argument);
-
-    for (auto& field : m_fields) {
-        field.name.visit_edges(visitor);
-        visitor.visit(field.initializer);
-    }
 }
 
 }
diff --git a/Userland/Libraries/LibJS/Runtime/FunctionObject.h b/Userland/Libraries/LibJS/Runtime/FunctionObject.h
index fbd3d3932e..ca41124d64 100644
--- a/Userland/Libraries/LibJS/Runtime/FunctionObject.h
+++ b/Userland/Libraries/LibJS/Runtime/FunctionObject.h
@@ -42,17 +42,6 @@ public:
     // This is for IsSimpleParameterList (static semantics)
     bool has_simple_parameter_list() const { return m_has_simple_parameter_list; }
 
-    // [[Fields]]
-    struct InstanceField {
-        StringOrSymbol name;
-        FunctionObject* initializer { nullptr };
-
-        void define_field(VM& vm, Object& receiver) const;
-    };
-
-    Vector<InstanceField> const& fields() const { return m_fields; }
-    void add_field(StringOrSymbol property_key, FunctionObject* initializer);
-
 protected:
     virtual void visit_edges(Visitor&) override;
 
@@ -66,7 +55,6 @@ private:
     Value m_bound_this;
     Vector<Value> m_bound_arguments;
     bool m_has_simple_parameter_list { false };
-    Vector<InstanceField> m_fields;
 };
 
 }
diff --git a/Userland/Libraries/LibJS/Runtime/VM.cpp b/Userland/Libraries/LibJS/Runtime/VM.cpp
index 17fe692db6..4622e60859 100644
--- a/Userland/Libraries/LibJS/Runtime/VM.cpp
+++ b/Userland/Libraries/LibJS/Runtime/VM.cpp
@@ -461,7 +461,7 @@ static void append_bound_and_passed_arguments(MarkedValueList& arguments, Vector
 }
 
 // 7.3.32 InitializeInstanceElements ( O, constructor ), https://tc39.es/ecma262/#sec-initializeinstanceelements
-void VM::initialize_instance_elements(Object& object, FunctionObject& constructor)
+void VM::initialize_instance_elements(Object& object, ECMAScriptFunctionObject& constructor)
 {
     for (auto& field : constructor.fields()) {
         field.define_field(*this, object);
@@ -509,9 +509,9 @@ Value VM::construct(FunctionObject& function, FunctionObject& new_target, Option
     // If we are a Derived constructor, |this| has not been constructed before super is called.
     callee_context.this_value = this_argument;
 
-    if (!is<ECMAScriptFunctionObject>(function) || static_cast<ECMAScriptFunctionObject&>(function).constructor_kind() == ECMAScriptFunctionObject::ConstructorKind::Base) {
+    if (is<ECMAScriptFunctionObject>(function) && static_cast<ECMAScriptFunctionObject&>(function).constructor_kind() == ECMAScriptFunctionObject::ConstructorKind::Base) {
         VERIFY(this_argument.is_object());
-        initialize_instance_elements(this_argument.as_object(), function);
+        initialize_instance_elements(this_argument.as_object(), static_cast<ECMAScriptFunctionObject&>(function));
         if (exception())
             return {};
     }
diff --git a/Userland/Libraries/LibJS/Runtime/VM.h b/Userland/Libraries/LibJS/Runtime/VM.h
index 4fa6d89e48..6f1f3ba2f1 100644
--- a/Userland/Libraries/LibJS/Runtime/VM.h
+++ b/Userland/Libraries/LibJS/Runtime/VM.h
@@ -280,7 +280,7 @@ public:
     Function<void(const Promise&)> on_promise_unhandled_rejection;
     Function<void(const Promise&)> on_promise_rejection_handled;
 
-    void initialize_instance_elements(Object& object, FunctionObject& constructor);
+    void initialize_instance_elements(Object& object, ECMAScriptFunctionObject& constructor);
 
     CustomData* custom_data() { return m_custom_data; }