LibJS+LibWeb: Add JS::Object::inherits(class_name)

To allow implementing the DOM class hierarchy in JS bindings, this
patch adds an inherits() function that can be used to ask an Object
if it inherits from a specific C++ class (by name).

The necessary overrides are baked into each Object subclass by the
new JS_OBJECT macro, which works similarly to C_OBJECT in LibCore.

Thanks to @Dexesttp for suggesting this approach. :^)

Libraries/LibJS/Runtime/Array.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class Array final : public Object {
+    JS_OBJECT(Array, Object);
+
 public:
     static Array* create(GlobalObject&);
 
@@ -40,7 +42,6 @@ public:
     static Array* typed_this(Interpreter&, GlobalObject&);
 
 private:
-    virtual const char* class_name() const override { return "Array"; }
     virtual bool is_array() const override { return true; }
 
     JS_DECLARE_NATIVE_GETTER(length_getter);

Libraries/LibJS/Runtime/ArrayConstructor.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class ArrayConstructor final : public NativeFunction {
+    JS_OBJECT(ArrayConstructor, NativeFunction);
+
 public:
     explicit ArrayConstructor(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
@@ -41,7 +43,6 @@ public:
 
 private:
     virtual bool has_constructor() const override { return true; }
-    virtual const char* class_name() const override { return "ArrayConstructor"; }
 
     JS_DECLARE_NATIVE_FUNCTION(is_array);
     JS_DECLARE_NATIVE_FUNCTION(of);

Libraries/LibJS/Runtime/ArrayPrototype.h

@@ -32,14 +32,14 @@
 namespace JS {
 
 class ArrayPrototype final : public Object {
+    JS_OBJECT(ArrayPrototype, Object);
+
 public:
     ArrayPrototype(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
     virtual ~ArrayPrototype() override;
 
 private:
-    virtual const char* class_name() const override { return "ArrayPrototype"; }
-
     JS_DECLARE_NATIVE_FUNCTION(filter);
     JS_DECLARE_NATIVE_FUNCTION(for_each);
     JS_DECLARE_NATIVE_FUNCTION(map);

Libraries/LibJS/Runtime/BigIntConstructor.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class BigIntConstructor final : public NativeFunction {
+    JS_OBJECT(BigIntConstructor, NativeFunction);
+
 public:
     explicit BigIntConstructor(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
@@ -41,7 +43,6 @@ public:
 
 private:
     virtual bool has_constructor() const override { return true; }
-    virtual const char* class_name() const override { return "BigIntConstructor"; }
 
     JS_DECLARE_NATIVE_FUNCTION(as_int_n);
     JS_DECLARE_NATIVE_FUNCTION(as_uint_n);

Libraries/LibJS/Runtime/BigIntObject.h

@@ -32,6 +32,8 @@
 namespace JS {
 
 class BigIntObject final : public Object {
+    JS_OBJECT(BigIntObject, Object);
+
 public:
     static BigIntObject* create(GlobalObject&, BigInt&);
 
@@ -46,7 +48,6 @@ public:
 
 private:
     virtual void visit_children(Visitor&) override;
-    virtual const char* class_name() const override { return "BigIntObject"; }
     virtual bool is_bigint_object() const override { return true; }
 
     BigInt& m_bigint;

Libraries/LibJS/Runtime/BigIntPrototype.h

@@ -31,14 +31,14 @@
 namespace JS {
 
 class BigIntPrototype final : public Object {
+    JS_OBJECT(BigIntPrototype, Object);
+
 public:
     explicit BigIntPrototype(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
     virtual ~BigIntPrototype() override;
 
 private:
-    virtual const char* class_name() const override { return "BigIntPrototype"; }
-
     JS_DECLARE_NATIVE_FUNCTION(to_string);
     JS_DECLARE_NATIVE_FUNCTION(to_locale_string);
     JS_DECLARE_NATIVE_FUNCTION(value_of);

Libraries/LibJS/Runtime/BooleanConstructor.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class BooleanConstructor final : public NativeFunction {
+    JS_OBJECT(BooleanConstructor, NativeFunction);
+
 public:
     explicit BooleanConstructor(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
@@ -41,7 +43,6 @@ public:
 
 private:
     virtual bool has_constructor() const override { return true; }
-    virtual const char* class_name() const override { return "BooleanConstructor"; }
 };
 
 }

Libraries/LibJS/Runtime/BooleanObject.h

@@ -30,6 +30,8 @@
 
 namespace JS {
 class BooleanObject : public Object {
+    JS_OBJECT(BooleanObject, Object);
+
 public:
     static BooleanObject* create(GlobalObject&, bool);
 
@@ -42,7 +44,6 @@ public:
     }
 
 private:
-    virtual const char* class_name() const override { return "BooleanObject"; }
     virtual bool is_boolean_object() const override { return true; }
     bool m_value { false };
 };

Libraries/LibJS/Runtime/BooleanPrototype.h

@@ -31,14 +31,14 @@
 namespace JS {
 
 class BooleanPrototype final : public BooleanObject {
+    JS_OBJECT(BooleanPrototype, BooleanObject);
+
 public:
     explicit BooleanPrototype(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
     virtual ~BooleanPrototype() override;
 
 private:
-    virtual const char* class_name() const override { return "BooleanPrototype"; }
-
     JS_DECLARE_NATIVE_FUNCTION(to_string);
     JS_DECLARE_NATIVE_FUNCTION(value_of);
 };

Libraries/LibJS/Runtime/BoundFunction.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class BoundFunction final : public Function {
+    JS_OBJECT(BoundFunction, Function);
+
 public:
     BoundFunction(GlobalObject&, Function& target_function, Value bound_this, Vector<Value> arguments, i32 length, Object* constructor_prototype);
     virtual void initialize(Interpreter&, GlobalObject&) override;
@@ -56,7 +58,6 @@ public:
 
 private:
     virtual bool is_bound_function() const override { return true; }
-    virtual const char* class_name() const override { return "BoundFunction"; }
 
     Function* m_target_function = nullptr;
     Object* m_constructor_prototype = nullptr;

Libraries/LibJS/Runtime/ConsoleObject.h

@@ -31,14 +31,14 @@
 namespace JS {
 
 class ConsoleObject final : public Object {
+    JS_OBJECT(ConsoleObject, Object);
+
 public:
     explicit ConsoleObject(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
     virtual ~ConsoleObject() override;
 
 private:
-    virtual const char* class_name() const override { return "ConsoleObject"; }
-
     JS_DECLARE_NATIVE_FUNCTION(log);
     JS_DECLARE_NATIVE_FUNCTION(debug);
     JS_DECLARE_NATIVE_FUNCTION(info);

Libraries/LibJS/Runtime/Date.h

@@ -32,6 +32,8 @@
 namespace JS {
 
 class Date final : public Object {
+    JS_OBJECT(Date, Object);
+
 public:
     static Date* create(GlobalObject&, Core::DateTime, u16 milliseconds);
 
@@ -57,7 +59,6 @@ public:
 
 private:
     virtual bool is_date() const final { return true; }
-    virtual const char* class_name() const override { return "Date"; }
 
     Core::DateTime m_datetime;
     u16 m_milliseconds;

Libraries/LibJS/Runtime/DateConstructor.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class DateConstructor final : public NativeFunction {
+    JS_OBJECT(DateConstructor, NativeFunction);
+
 public:
     explicit DateConstructor(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
@@ -41,7 +43,6 @@ public:
 
 private:
     virtual bool has_constructor() const override { return true; }
-    virtual const char* class_name() const override { return "DateConstructor"; }
 
     JS_DECLARE_NATIVE_FUNCTION(now);
 };

Libraries/LibJS/Runtime/DatePrototype.h

@@ -31,14 +31,13 @@
 namespace JS {
 
 class DatePrototype final : public Object {
+    JS_OBJECT(DatePrototype, Object);
 public:
     explicit DatePrototype(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
     virtual ~DatePrototype() override;
 
 private:
-    virtual const char* class_name() const override { return "DatePrototype"; }
-
     JS_DECLARE_NATIVE_FUNCTION(get_date);
     JS_DECLARE_NATIVE_FUNCTION(get_day);
     JS_DECLARE_NATIVE_FUNCTION(get_full_year);

Libraries/LibJS/Runtime/Error.cpp

@@ -57,7 +57,6 @@ Error::~Error()
     {                                                                                                                     \
     }                                                                                                                     \
     ClassName::~ClassName() { }                                                                                           \
-    const char* ClassName::class_name() const { return #ClassName; }
 
 JS_ENUMERATE_ERROR_SUBCLASSES
 #undef __JS_ENUMERATE

Libraries/LibJS/Runtime/Error.h

@@ -32,6 +32,8 @@
 namespace JS {
 
 class Error : public Object {
+    JS_OBJECT(Error, Object);
+
 public:
     static Error* create(GlobalObject&, const FlyString& name, const String& message);
 
@@ -45,7 +47,6 @@ public:
 
 private:
     virtual bool is_error() const final { return true; }
-    virtual const char* class_name() const override { return "Error"; }
 
     FlyString m_name;
     String m_message;
@@ -53,14 +54,13 @@ private:
 
 #define DECLARE_ERROR_SUBCLASS(ClassName, snake_name, PrototypeName, ConstructorName) \
     class ClassName final : public Error {                                            \
+        JS_OBJECT(ClassName, Error);                                                  \
+                                                                                      \
     public:                                                                           \
         static ClassName* create(GlobalObject&, const String& message);               \
                                                                                       \
         ClassName(const String& message, Object& prototype);                          \
         virtual ~ClassName() override;                                                \
-                                                                                      \
-    private:                                                                          \
-        virtual const char* class_name() const override;                              \
     };
 
 #define __JS_ENUMERATE(ClassName, snake_name, PrototypeName, ConstructorName) \

Libraries/LibJS/Runtime/ErrorConstructor.h

@@ -32,6 +32,8 @@
 namespace JS {
 
 class ErrorConstructor final : public NativeFunction {
+    JS_OBJECT(ErrorConstructor, NativeFunction);
+
 public:
     explicit ErrorConstructor(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
@@ -42,11 +44,12 @@ public:
 
 private:
     virtual bool has_constructor() const override { return true; }
-    virtual const char* class_name() const override { return "ErrorConstructor"; }
 };
 
 #define DECLARE_ERROR_SUBCLASS_CONSTRUCTOR(ClassName, snake_name, PrototypeName, ConstructorName) \
     class ConstructorName final : public NativeFunction {                                         \
+        JS_OBJECT(ConstructorName, NativeFunction);                                               \
+                                                                                                  \
     public:                                                                                       \
         explicit ConstructorName(GlobalObject&);                                                  \
         virtual void initialize(Interpreter&, GlobalObject&) override;                            \
@@ -56,7 +59,6 @@ private:
                                                                                                   \
     private:                                                                                      \
         virtual bool has_constructor() const override { return true; }                            \
-        virtual const char* class_name() const override { return #ClassName "Constructor"; }      \
     };
 
 #define __JS_ENUMERATE(ClassName, snake_name, PrototypeName, ConstructorName) \

Libraries/LibJS/Runtime/ErrorPrototype.cpp

@@ -126,8 +126,7 @@ JS_DEFINE_NATIVE_FUNCTION(ErrorPrototype::to_string)
         : Object(global_object.error_prototype())                             \
     {                                                                         \
     }                                                                         \
-    PrototypeName::~PrototypeName() { }                                       \
+    PrototypeName::~PrototypeName() { }
-    const char* PrototypeName::class_name() const { return #PrototypeName; }
 
 JS_ENUMERATE_ERROR_SUBCLASSES
 #undef __JS_ENUMERATE

Libraries/LibJS/Runtime/ErrorPrototype.h

@@ -31,14 +31,14 @@
 namespace JS {
 
 class ErrorPrototype final : public Object {
+    JS_OBJECT(ErrorPrototype, Object);
+
 public:
     explicit ErrorPrototype(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
     virtual ~ErrorPrototype() override;
 
 private:
-    virtual const char* class_name() const override { return "ErrorPrototype"; }
-
     JS_DECLARE_NATIVE_FUNCTION(to_string);
 
     JS_DECLARE_NATIVE_GETTER(name_getter);
@@ -49,13 +49,12 @@ private:
 
 #define DECLARE_ERROR_SUBCLASS_PROTOTYPE(ClassName, snake_name, PrototypeName, ConstructorName) \
     class PrototypeName final : public Object {                                                 \
+        JS_OBJECT(PrototypeName, Object);                                                       \
+                                                                                                \
     public:                                                                                     \
         explicit PrototypeName(GlobalObject&);                                                  \
         virtual void initialize(Interpreter&, GlobalObject&) override { }                       \
         virtual ~PrototypeName() override;                                                      \
-                                                                                                \
-    private:                                                                                    \
-        virtual const char* class_name() const override;                                        \
     };
 
 #define __JS_ENUMERATE(ClassName, snake_name, PrototypeName, ConstructorName) \

Libraries/LibJS/Runtime/Function.h

@@ -32,6 +32,8 @@
 namespace JS {
 
 class Function : public Object {
+    JS_OBJECT(Function, Object);
+
 public:
     virtual ~Function();
     virtual void initialize(Interpreter&, GlobalObject&) override { }
@@ -60,7 +62,6 @@ public:
 protected:
     explicit Function(Object& prototype);
     Function(Object& prototype, Value bound_this, Vector<Value> bound_arguments);
-    virtual const char* class_name() const override { return "Function"; }
 
 private:
     virtual bool is_function() const final { return true; }

Libraries/LibJS/Runtime/FunctionConstructor.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class FunctionConstructor final : public NativeFunction {
+    JS_OBJECT(FunctionConstructor, NativeFunction);
+
 public:
     explicit FunctionConstructor(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
@@ -41,7 +43,6 @@ public:
 
 private:
     virtual bool has_constructor() const override { return true; }
-    virtual const char* class_name() const override { return "FunctionConstructor"; }
 };
 
 }

Libraries/LibJS/Runtime/FunctionPrototype.h

@@ -31,14 +31,14 @@
 namespace JS {
 
 class FunctionPrototype final : public Object {
+    JS_OBJECT(FunctionPrototype, Object);
+
 public:
     explicit FunctionPrototype(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
     virtual ~FunctionPrototype() override;
 
 private:
-    virtual const char* class_name() const override { return "FunctionPrototype"; }
-
     JS_DECLARE_NATIVE_FUNCTION(apply);
     JS_DECLARE_NATIVE_FUNCTION(bind);
     JS_DECLARE_NATIVE_FUNCTION(call);

Libraries/LibJS/Runtime/GlobalObject.h

@@ -32,6 +32,8 @@
 namespace JS {
 
 class GlobalObject : public Object {
+    JS_OBJECT(GlobalObject, Object);
+
 public:
     explicit GlobalObject();
     virtual void initialize();
@@ -53,8 +55,6 @@ protected:
     void add_constructor(const FlyString& property_name, ConstructorType*&, Object& prototype);
 
 private:
-    virtual const char* class_name() const override { return "GlobalObject"; }
-
     JS_DECLARE_NATIVE_FUNCTION(gc);
     JS_DECLARE_NATIVE_FUNCTION(is_nan);
     JS_DECLARE_NATIVE_FUNCTION(is_finite);

Libraries/LibJS/Runtime/JSONObject.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class JSONObject final : public Object {
+    JS_OBJECT(JSONObject, Object);
+
 public:
     explicit JSONObject(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
@@ -45,8 +47,6 @@ private:
         Optional<Vector<String>> property_list;
     };
 
-    virtual const char* class_name() const override { return "JSONObject"; }
-
     // Stringify helpers
     static String serialize_json_property(Interpreter&, StringifyState&, const PropertyName& key, Object* holder);
     static String serialize_json_object(Interpreter&, StringifyState&, Object&);

Libraries/LibJS/Runtime/MathObject.h

@@ -31,14 +31,14 @@
 namespace JS {
 
 class MathObject final : public Object {
+    JS_OBJECT(MathObject, Object);
+
 public:
     explicit MathObject(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
     virtual ~MathObject() override;
 
 private:
-    virtual const char* class_name() const override { return "MathObject"; }
-
     JS_DECLARE_NATIVE_FUNCTION(abs);
     JS_DECLARE_NATIVE_FUNCTION(random);
     JS_DECLARE_NATIVE_FUNCTION(sqrt);

Libraries/LibJS/Runtime/NativeFunction.h

@@ -32,6 +32,8 @@
 namespace JS {
 
 class NativeFunction : public Function {
+    JS_OBJECT(NativeFunction, Function);
+
 public:
     static NativeFunction* create(Interpreter&, GlobalObject&, const FlyString& name, AK::Function<Value(Interpreter&, GlobalObject&)>);
 
@@ -51,7 +53,6 @@ protected:
 
 private:
     virtual bool is_native_function() const override { return true; }
-    virtual const char* class_name() const override { return "NativeFunction"; }
     virtual LexicalEnvironment* create_environment() override final { return nullptr; }
 
     FlyString m_name;

Libraries/LibJS/Runtime/NativeProperty.h

@@ -32,6 +32,8 @@
 namespace JS {
 
 class NativeProperty final : public Object {
+    JS_OBJECT(NativeProperty, Object);
+
 public:
     NativeProperty(AK::Function<Value(Interpreter&, GlobalObject&)> getter, AK::Function<void(Interpreter&, GlobalObject&, Value)> setter);
     virtual ~NativeProperty() override;
@@ -41,7 +43,6 @@ public:
 
 private:
     virtual bool is_native_property() const override { return true; }
-    virtual const char* class_name() const override { return "NativeProperty"; }
 
     AK::Function<Value(Interpreter&, GlobalObject&)> m_getter;
     AK::Function<void(Interpreter&, GlobalObject&, Value)> m_setter;

Libraries/LibJS/Runtime/NumberConstructor.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class NumberConstructor final : public NativeFunction {
+    JS_OBJECT(NumberConstructor, NativeFunction);
+
 public:
     explicit NumberConstructor(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
@@ -41,7 +43,6 @@ public:
 
 private:
     virtual bool has_constructor() const override { return true; }
-    virtual const char* class_name() const override { return "NumberConstructor"; }
 
     JS_DECLARE_NATIVE_FUNCTION(is_finite);
     JS_DECLARE_NATIVE_FUNCTION(is_integer);

Libraries/LibJS/Runtime/NumberObject.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class NumberObject : public Object {
+    JS_OBJECT(NumberObject, Object);
+
 public:
     static NumberObject* create(GlobalObject&, double);
 
@@ -41,8 +43,6 @@ public:
     virtual Value value_of() const override { return Value(m_value); }
 
 private:
-    virtual const char* class_name() const override { return "NumberObject"; }
-
     double m_value { 0 };
 };
 

Libraries/LibJS/Runtime/NumberPrototype.h

@@ -31,12 +31,11 @@
 namespace JS {
 
 class NumberPrototype final : public NumberObject {
+    JS_OBJECT(NumberPrototype, NumberObject);
+
 public:
     explicit NumberPrototype(GlobalObject&);
     virtual ~NumberPrototype() override;
-
-private:
-    virtual const char* class_name() const override { return "NumberPrototype"; }
 };
 
 }

Libraries/LibJS/Runtime/Object.h

@@ -39,6 +39,12 @@
 
 namespace JS {
 
+#define JS_OBJECT(class_, base_class)                                   \
+public:                                                                 \
+    using Base = base_class;                                            \
+    virtual const char* class_name() const override { return #class_; } \
+    virtual bool inherits(const StringView& class_name) const override { return class_name == #class_ || Base::inherits(class_name); }
+
 struct PropertyDescriptor {
     PropertyAttributes attributes;
     Value value;
@@ -60,6 +66,8 @@ public:
     virtual void initialize(Interpreter&, GlobalObject&) override;
     virtual ~Object();
 
+    virtual bool inherits(const StringView& class_name) const { return class_name == this->class_name(); }
+
     enum class GetOwnPropertyMode {
         Key,
         Value,
@@ -111,8 +119,6 @@ public:
     virtual bool is_symbol_object() const { return false; }
     virtual bool is_bigint_object() const { return false; }
 
-    virtual bool is_web_wrapper() const { return false; }
-
     virtual const char* class_name() const override { return "Object"; }
     virtual void visit_children(Cell::Visitor&) override;
 

Libraries/LibJS/Runtime/ObjectConstructor.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class ObjectConstructor final : public NativeFunction {
+    JS_OBJECT(ObjectConstructor, NativeFunction);
+
 public:
     explicit ObjectConstructor(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
@@ -41,7 +43,6 @@ public:
 
 private:
     virtual bool has_constructor() const override { return true; }
-    virtual const char* class_name() const override { return "ObjectConstructor"; }
 
     JS_DECLARE_NATIVE_FUNCTION(define_property_);
     JS_DECLARE_NATIVE_FUNCTION(is);

Libraries/LibJS/Runtime/ObjectPrototype.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class ObjectPrototype final : public Object {
+    JS_OBJECT(ObjectPrototype, Object);
+
 public:
     explicit ObjectPrototype(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
@@ -40,8 +42,6 @@ public:
     JS_DECLARE_NATIVE_FUNCTION(to_string);
 
 private:
-    virtual const char* class_name() const override { return "ObjectPrototype"; }
-
     JS_DECLARE_NATIVE_FUNCTION(has_own_property);
     JS_DECLARE_NATIVE_FUNCTION(to_locale_string);
     JS_DECLARE_NATIVE_FUNCTION(value_of);

Libraries/LibJS/Runtime/ProxyConstructor.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class ProxyConstructor final : public NativeFunction {
+    JS_OBJECT(ProxyConstructor, NativeFunction);
+
 public:
     explicit ProxyConstructor(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
@@ -41,7 +43,6 @@ public:
 
 private:
     virtual bool has_constructor() const override { return true; }
-    virtual const char* class_name() const override { return "ProxyConstructor"; }
 };
 
 }

Libraries/LibJS/Runtime/ProxyObject.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class ProxyObject : public Object {
+    JS_OBJECT(ProxyObject, Object);
+
 public:
     static ProxyObject* create(GlobalObject&, Object& target, Object& handler);
 
@@ -56,7 +58,6 @@ public:
 
 private:
     virtual void visit_children(Visitor&) override;
-    virtual const char* class_name() const override { return "ProxyObject"; }
     virtual bool is_proxy_object() const override { return true; }
     virtual bool is_array() const override { return m_target.is_array(); };
 

Libraries/LibJS/Runtime/ProxyPrototype.h

@@ -31,12 +31,11 @@
 namespace JS {
 
 class ProxyPrototype final : public Object {
+    JS_OBJECT(ProxyPrototype, Object);
+
 public:
     explicit ProxyPrototype(GlobalObject&);
     virtual ~ProxyPrototype() override;
-
-private:
-    virtual const char* class_name() const override { return "ProxyPrototype"; }
 };
 
 }

Libraries/LibJS/Runtime/ReflectObject.h

@@ -31,14 +31,14 @@
 namespace JS {
 
 class ReflectObject final : public Object {
+    JS_OBJECT(ReflectObject, Object);
+
 public:
     explicit ReflectObject(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
     virtual ~ReflectObject() override;
 
 private:
-    virtual const char* class_name() const override { return "ReflectObject"; }
-
     JS_DECLARE_NATIVE_FUNCTION(apply);
     JS_DECLARE_NATIVE_FUNCTION(construct);
     JS_DECLARE_NATIVE_FUNCTION(define_property);

Libraries/LibJS/Runtime/RegExpConstructor.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class RegExpConstructor final : public NativeFunction {
+    JS_OBJECT(RegExpConstructor, NativeFunction);
+
 public:
     explicit RegExpConstructor(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
@@ -41,7 +43,6 @@ public:
 
 private:
     virtual bool has_constructor() const override { return true; }
-    virtual const char* class_name() const override { return "RegExpConstructor"; }
 };
 
 }

Libraries/LibJS/Runtime/RegExpObject.h

@@ -32,6 +32,8 @@
 namespace JS {
 
 class RegExpObject : public Object {
+    JS_OBJECT(RegExpObject, Object);
+
 public:
     static RegExpObject* create(GlobalObject&, String content, String flags);
 
@@ -44,7 +46,6 @@ public:
     Value to_string() const override;
 
 private:
-    virtual const char* class_name() const override { return "RegExpObject"; }
     virtual bool is_regexp_object() const override { return true; }
 
     String m_content;

Libraries/LibJS/Runtime/RegExpPrototype.h

@@ -31,12 +31,11 @@
 namespace JS {
 
 class RegExpPrototype final : public RegExpObject {
+    JS_OBJECT(RegExpPrototype, RegExpObject);
+
 public:
     explicit RegExpPrototype(GlobalObject&);
     virtual ~RegExpPrototype() override;
-
-private:
-    virtual const char* class_name() const override { return "RegExpPrototype"; }
 };
 
 }

Libraries/LibJS/Runtime/ScriptFunction.h

@@ -32,6 +32,8 @@
 namespace JS {
 
 class ScriptFunction final : public Function {
+    JS_OBJECT(ScriptFunction, Function);
+
 public:
     static ScriptFunction* create(GlobalObject&, const FlyString& name, const Statement& body, Vector<FunctionNode::Parameter> parameters, i32 m_function_length, LexicalEnvironment* parent_environment, bool is_arrow_function = false);
 
@@ -50,7 +52,6 @@ public:
 
 private:
     virtual bool is_script_function() const override { return true; }
-    virtual const char* class_name() const override { return "ScriptFunction"; }
     virtual LexicalEnvironment* create_environment() override;
     virtual void visit_children(Visitor&) override;
 

Libraries/LibJS/Runtime/StringConstructor.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class StringConstructor final : public NativeFunction {
+    JS_OBJECT(StringConstructor, NativeFunction);
+
 public:
     explicit StringConstructor(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
@@ -41,7 +43,6 @@ public:
 
 private:
     virtual bool has_constructor() const override { return true; }
-    virtual const char* class_name() const override { return "StringConstructor"; }
 
     JS_DECLARE_NATIVE_FUNCTION(raw);
     JS_DECLARE_NATIVE_FUNCTION(from_char_code);

Libraries/LibJS/Runtime/StringObject.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class StringObject : public Object {
+    JS_OBJECT(StringObject, Object);
+
 public:
     static StringObject* create(GlobalObject&, PrimitiveString&);
 
@@ -45,7 +47,6 @@ public:
 
 private:
     virtual void visit_children(Visitor&) override;
-    virtual const char* class_name() const override { return "StringObject"; }
     virtual bool is_string_object() const override { return true; }
 
     PrimitiveString& m_string;

Libraries/LibJS/Runtime/StringPrototype.h

@@ -31,14 +31,14 @@
 namespace JS {
 
 class StringPrototype final : public StringObject {
+    JS_OBJECT(StringPrototype, StringObject);
+
 public:
     explicit StringPrototype(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
     virtual ~StringPrototype() override;
 
 private:
-    virtual const char* class_name() const override { return "StringPrototype"; }
-
     JS_DECLARE_NATIVE_FUNCTION(char_at);
     JS_DECLARE_NATIVE_FUNCTION(repeat);
     JS_DECLARE_NATIVE_FUNCTION(starts_with);

Libraries/LibJS/Runtime/SymbolConstructor.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class SymbolConstructor final : public NativeFunction {
+    JS_OBJECT(SymbolConstructor, NativeFunction);
+
 public:
     explicit SymbolConstructor(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
@@ -41,7 +43,6 @@ public:
 
 private:
     virtual bool has_constructor() const override { return true; }
-    virtual const char* class_name() const override { return "SymbolConstructor"; }
 
     JS_DECLARE_NATIVE_FUNCTION(for_);
     JS_DECLARE_NATIVE_FUNCTION(key_for);

Libraries/LibJS/Runtime/SymbolObject.h

@@ -32,6 +32,8 @@
 namespace JS {
 
 class SymbolObject : public Object {
+    JS_OBJECT(SymbolObject, Object);
+
 public:
     static SymbolObject* create(GlobalObject&, Symbol&);
 
@@ -70,7 +72,6 @@ public:
 
 private:
     virtual void visit_children(Visitor&) override;
-    virtual const char* class_name() const override { return "SymbolObject"; }
     virtual bool is_symbol_object() const override { return true; }
 
     Symbol& m_symbol;

Libraries/LibJS/Runtime/SymbolPrototype.h

@@ -31,14 +31,14 @@
 namespace JS {
 
 class SymbolPrototype final : public Object {
+    JS_OBJECT(SymbolPrototype, Object);
+
 public:
     explicit SymbolPrototype(GlobalObject&);
     virtual void initialize(Interpreter&, GlobalObject&) override;
     virtual ~SymbolPrototype() override;
 
 private:
-    virtual const char* class_name() const override { return "SymbolPrototype"; }
-
     JS_DECLARE_NATIVE_GETTER(description_getter);
 
     JS_DECLARE_NATIVE_FUNCTION(to_string);

Libraries/LibJS/Runtime/Uint8ClampedArray.h

@@ -31,6 +31,8 @@
 namespace JS {
 
 class Uint8ClampedArray final : public Object {
+    JS_OBJECT(Uint8ClampedArray, Object);
+
 public:
     static Uint8ClampedArray* create(GlobalObject&, u32 length);
 
@@ -46,8 +48,6 @@ public:
     const u8* data() const { return m_data; }
 
 private:
-    virtual const char* class_name() const override { return "Uint8ClampedArray"; }
-
     JS_DECLARE_NATIVE_GETTER(length_getter);
 
     u8* m_data { nullptr };

Libraries/LibWeb/Bindings/CanvasRenderingContext2DWrapper.h

@@ -32,6 +32,7 @@ namespace Web {
 namespace Bindings {
 
 class CanvasRenderingContext2DWrapper final : public Wrapper {
+    JS_OBJECT(CanvasRenderingContext2DWrapper, Wrapper);
 public:
     CanvasRenderingContext2DWrapper(JS::GlobalObject&, CanvasRenderingContext2D&);
     virtual void initialize(JS::Interpreter&, JS::GlobalObject&) override;
@@ -41,8 +42,6 @@ public:
     const CanvasRenderingContext2D& impl() const { return m_impl; }
 
 private:
-    virtual const char* class_name() const override { return "CanvasRenderingContext2DWrapper"; }
-
     JS_DECLARE_NATIVE_FUNCTION(fill_rect);
     JS_DECLARE_NATIVE_FUNCTION(stroke_rect);
     JS_DECLARE_NATIVE_FUNCTION(draw_image);

Libraries/LibWeb/Bindings/EventListenerWrapper.h

@@ -32,6 +32,8 @@ namespace Web {
 namespace Bindings {
 
 class EventListenerWrapper final : public Wrapper {
+    JS_OBJECT(EventListenerWrapper, Wrapper);
+
 public:
     EventListenerWrapper(JS::GlobalObject&, EventListener&);
     virtual ~EventListenerWrapper() override;
@@ -40,8 +42,6 @@ public:
     const EventListener& impl() const { return *m_impl; }
 
 private:
-    virtual const char* class_name() const override { return "EventListenerWrapper"; }
-
     NonnullRefPtr<EventListener> m_impl;
 };
 

Libraries/LibWeb/Bindings/EventWrapper.h

@@ -32,6 +32,8 @@ namespace Web {
 namespace Bindings {
 
 class EventWrapper : public Wrapper {
+    JS_OBJECT(EventWrapper, Wrapper);
+
 public:
     EventWrapper(JS::GlobalObject&, Event&);
     virtual ~EventWrapper() override;
@@ -40,8 +42,6 @@ public:
     const Event& event() const { return m_event; }
 
 private:
-    virtual const char* class_name() const override { return "EventWrapper"; }
-
     NonnullRefPtr<Event> m_event;
 };
 

Libraries/LibWeb/Bindings/ImageDataWrapper.h

@@ -32,6 +32,8 @@ namespace Web {
 namespace Bindings {
 
 class ImageDataWrapper : public Wrapper {
+    JS_OBJECT(ImageDataWrapper, Wrapper);
+
 public:
     ImageDataWrapper(JS::GlobalObject&, ImageData&);
     virtual void initialize(JS::Interpreter&, JS::GlobalObject&) override;
@@ -41,8 +43,6 @@ public:
     const ImageData& impl() const { return m_impl; }
 
 private:
-    virtual const char* class_name() const override { return "ImageDataWrapper"; }
-
     JS_DECLARE_NATIVE_GETTER(width_getter);
     JS_DECLARE_NATIVE_GETTER(height_getter);
     JS_DECLARE_NATIVE_GETTER(data_getter);

Libraries/LibWeb/Bindings/LocationObject.h

@@ -33,14 +33,14 @@ namespace Web {
 namespace Bindings {
 
 class LocationObject final : public JS::Object {
+    JS_OBJECT(LocationObject, JS::Object);
+
 public:
     explicit LocationObject(JS::GlobalObject&);
     virtual void initialize(JS::Interpreter&, JS::GlobalObject&) override;
     virtual ~LocationObject() override;
 
 private:
-    virtual const char* class_name() const override { return "LocationObject"; }
-
     JS_DECLARE_NATIVE_FUNCTION(reload);
 
     JS_DECLARE_NATIVE_GETTER(href_getter);

Libraries/LibWeb/Bindings/NavigatorObject.h

@@ -33,14 +33,14 @@ namespace Web {
 namespace Bindings {
 
 class NavigatorObject final : public JS::Object {
+    JS_OBJECT(NavigatorObject, JS::Object);
+
 public:
     NavigatorObject(JS::GlobalObject&);
     virtual void initialize(JS::Interpreter&, JS::GlobalObject&) override;
     virtual ~NavigatorObject() override;
 
 private:
-    virtual const char* class_name() const override { return "NavigatorObject"; }
-
     JS_DECLARE_NATIVE_GETTER(user_agent_getter);
 };
 

Libraries/LibWeb/Bindings/Wrapper.h

@@ -37,20 +37,14 @@ namespace Bindings {
 class Wrapper
     : public JS::Object
     , public Weakable<Wrapper> {
-public:
+    JS_OBJECT(Wrapper, JS::Object);
-    virtual bool is_event_target_wrapper() const { return false; }
-    virtual bool is_node_wrapper() const { return false; }
-    virtual bool is_document_wrapper() const { return false; }
-    virtual bool is_element_wrapper() const { return false; }
-    virtual bool is_htmlelement_wrapper() const { return false; }
 
+public:
 protected:
     explicit Wrapper(Object& prototype)
         : Object(&prototype)
     {
     }
-
-    virtual bool is_web_wrapper() const final { return true; }
 };
 
 }

Libraries/LibWeb/Bindings/XMLHttpRequestPrototype.h

@@ -32,14 +32,14 @@ namespace Web {
 namespace Bindings {
 
 class XMLHttpRequestPrototype final : public JS::Object {
+    JS_OBJECT(XMLHttpRequestPrototype, JS::Object);
+
 public:
     explicit XMLHttpRequestPrototype(JS::GlobalObject&);
     virtual void initialize(JS::Interpreter&, JS::GlobalObject&) override;
     virtual ~XMLHttpRequestPrototype() override;
 
 private:
-    virtual const char* class_name() const override { return "XMLHttpRequestPrototype"; }
-
     JS_DECLARE_NATIVE_FUNCTION(open);
     JS_DECLARE_NATIVE_FUNCTION(send);
 

Libraries/LibWeb/CodeGenerators/WrapperGenerator.cpp

@@ -315,6 +315,7 @@ static void generate_header(const IDL::Interface& interface)
     out() << "namespace Bindings {";
 
     out() << "class " << wrapper_class << " : public " << wrapper_base_class << " {";
+    out() << "    JS_OBJECT(" << wrapper_class << ", " << wrapper_base_class << ");";
     out() << "public:";
     out() << "    " << wrapper_class << "(JS::GlobalObject&, " << interface.name << "&);";
     out() << "    virtual void initialize(JS::Interpreter&, JS::GlobalObject&) override;";
@@ -332,7 +333,6 @@ static void generate_header(const IDL::Interface& interface)
     out() << "    virtual bool " << is_foo_wrapper_name << "() const final { return true; }";
 
     out() << "private:";
-    out() << "    virtual const char* class_name() const override { return \"" << interface.name << "\"; }";
 
     for (auto& function : interface.functions) {
         out() << "    JS_DECLARE_NATIVE_FUNCTION(" << snake_name(function.name) << ");";
@@ -412,8 +412,7 @@ void generate_implementation(const IDL::Interface& interface)
     out() << "    auto* this_object = interpreter.this_value(global_object).to_object(interpreter, global_object);";
     out() << "    if (!this_object)";
     out() << "        return {};";
-    auto is_foo_wrapper_name = snake_name(String::format("Is%s", wrapper_class.characters()));
+    out() << "    if (!this_object->inherits(\"" << wrapper_class << "\")) {";
-    out() << "    if (!this_object->is_web_wrapper() || !static_cast<Wrapper*>(this_object)->" << is_foo_wrapper_name << "()) {";
     out() << "        interpreter.throw_exception<JS::TypeError>(JS::ErrorType::NotA, \"" << interface.name << "\");";
     out() << "        return nullptr;";
     out() << "    }";
@@ -441,8 +440,7 @@ void generate_implementation(const IDL::Interface& interface)
             out() << "    auto " << cpp_name << "_object = " << js_name << js_suffix << ".to_object(interpreter, global_object);";
             out() << "    if (interpreter.exception())";
             generate_return();
-            auto is_foo_wrapper_name = snake_name(String::format("Is%sWrapper", parameter.type.name.characters()));
+            out() << "    if (!" << cpp_name << "_object->inherits(\"" << parameter.type.name << "Wrapper\")) {";
-            out() << "    if (!" << cpp_name << "_object->is_web_wrapper() || !static_cast<Wrapper*>(" << cpp_name << "_object)->" << is_foo_wrapper_name << "()) {";
             out() << "        interpreter.throw_exception<JS::TypeError>(JS::ErrorType::NotA, \"" << parameter.type.name << "\");";
             generate_return();
             out() << "    }";