src: interject class TypeTaggable

doc/external.md

@@ -1,6 +1,6 @@
 # External (template)
 
-Class `Napi::External<T>` inherits from class [`Napi::Value`][].
+Class `Napi::External<T>` inherits from class [`Napi::TypeTaggable`][].
 
 The `Napi::External` template class implements the ability to create a `Napi::Value` object with arbitrary C++ data. It is the user's responsibility to manage the memory for the arbitrary C++ data.
 
@@ -67,4 +67,4 @@ T* Napi::External::Data() const;
 
 Returns a pointer to the arbitrary C++ data held by the `Napi::External` object.
 
-[`Napi::Value`]: ./value.md
+[`Napi::TypeTaggable`]: ./type_taggable.md

doc/object.md

@@ -1,6 +1,6 @@
 # Object
 
-Class `Napi::Object` inherits from class [`Napi::Value`][].
+Class `Napi::Object` inherits from class [`Napi::TypeTaggable`][].
 
 The `Napi::Object` class corresponds to a JavaScript object. It is extended by the following node-addon-api classes that you may use when working with more specific types:
 
@@ -241,33 +241,6 @@ from being added to it and marking all existing properties as non-configurable.
 Values of present properties can still be changed as long as they are
 writable.
 
-### TypeTag()
-
-```cpp
-void Napi::Object::TypeTag(const napi_type_tag* type_tag) const;
-```
-
-- `[in] type_tag`: The tag with which this object is to be marked.
-
-The `Napi::Object::TypeTag()` method associates the value of the `type_tag`
-pointer with this JavaScript object. `Napi::Object::CheckTypeTag()` can then be
-used to compare the tag that was attached to this object with one owned by the
-addon to ensure that this object has the right type.
-
-### CheckTypeTag()
-
-```cpp
-bool Napi::Object::CheckTypeTag(const napi_type_tag* type_tag) const;
-```
-
-- `[in] type_tag`: The tag with which to compare any tag found on this object.
-
-The `Napi::Object::CheckTypeTag()` method compares the pointer given as
-`type_tag` with any that can be found on this JavaScript object. If no tag is
-found on this object or, if a tag is found but it does not match `type_tag`,
-then the return value is `false`. If a tag is found and it matches `type_tag`,
-then the return value is `true`.
-
 ### operator\[\]()
 
 ```cpp
@@ -434,5 +407,5 @@ void Increment(const CallbackInfo& info) {
 }
 ```
 
-[`Napi::Value`]: ./value.md
+[`Napi::TypeTaggable`]: ./type_taggable.md
 [`Napi::Value::From`]: ./value.md#from

doc/type_taggable.md

@@ -0,0 +1,38 @@
+# TypeTaggable
+
+Class `Napi::TypeTaggable` inherits from class [`Napi::Value`][].
+
+The `Napi::TypeTaggable` class is the base class for [`Napi::Object`][] and
+[`Napi::External`][]. It adds type-tagging capabilities to both. It is an
+abstract-only base class.
+
+### TypeTag()
+
+```cpp
+void Napi::TypeTaggable::TypeTag(const napi_type_tag* type_tag) const;
+```
+
+- `[in] type_tag`: The tag with which this object or external is to be marked.
+
+The `Napi::TypeTaggable::TypeTag()` method associates the value of the
+`type_tag` pointer with this JavaScript object or external.
+`Napi::TypeTaggable::CheckTypeTag()` can then be used to compare the tag that
+was attached with one owned by the add-on to ensure that this object or external
+has the right type.
+
+### CheckTypeTag()
+
+```cpp
+bool Napi::TypeTaggable::CheckTypeTag(const napi_type_tag* type_tag) const;
+```
+
+- `[in] type_tag`: The tag with which to compare any tag found on this object or
+  external.
+
+The `Napi::TypeTaggable::CheckTypeTag()` method compares the pointer given as
+`type_tag` with any that can be found on this JavaScript object or external. If
+no tag is found or if a tag is found but it does not match `type_tag`, then the
+return value is `false`. If a tag is found and it matches `type_tag`, then the
+return value is `true`.
+
+[`Napi::Value`]: ./value.md

napi-inl.h

@@ -1248,6 +1248,32 @@ String String::From(napi_env env, const T& value) {
   return Helper::From(env, value);
 }
 
+////////////////////////////////////////////////////////////////////////////////
+// TypeTaggable class
+////////////////////////////////////////////////////////////////////////////////
+
+inline TypeTaggable::TypeTaggable() : Value() {}
+
+inline TypeTaggable::TypeTaggable(napi_env _env, napi_value _value)
+    : Value(_env, _value) {}
+
+#if NAPI_VERSION >= 8
+
+inline void TypeTaggable::TypeTag(const napi_type_tag* type_tag) const {
+  napi_status status = napi_type_tag_object(_env, _value, type_tag);
+  NAPI_THROW_IF_FAILED_VOID(_env, status);
+}
+
+inline bool TypeTaggable::CheckTypeTag(const napi_type_tag* type_tag) const {
+  bool result;
+  napi_status status =
+      napi_check_object_type_tag(_env, _value, type_tag, &result);
+  NAPI_THROW_IF_FAILED(_env, status, false);
+  return result;
+}
+
+#endif  // NAPI_VERSION >= 8
+
 ////////////////////////////////////////////////////////////////////////////////
 // Object class
 ////////////////////////////////////////////////////////////////////////////////
@@ -1287,9 +1313,10 @@ inline Object Object::New(napi_env env) {
   return Object(env, value);
 }
 
-inline Object::Object() : Value() {}
+inline Object::Object() : TypeTaggable() {}
 
-inline Object::Object(napi_env env, napi_value value) : Value(env, value) {}
+inline Object::Object(napi_env env, napi_value value)
+    : TypeTaggable(env, value) {}
 
 inline Object::PropertyLValue<std::string> Object::operator[](
     const char* utf8name) {
@@ -1632,19 +1659,6 @@ inline MaybeOrValue<bool> Object::Seal() const {
   napi_status status = napi_object_seal(_env, _value);
   NAPI_RETURN_OR_THROW_IF_FAILED(_env, status, status == napi_ok, bool);
 }
-
-inline void Object::TypeTag(const napi_type_tag* type_tag) const {
-  napi_status status = napi_type_tag_object(_env, _value, type_tag);
-  NAPI_THROW_IF_FAILED_VOID(_env, status);
-}
-
-inline bool Object::CheckTypeTag(const napi_type_tag* type_tag) const {
-  bool result;
-  napi_status status =
-      napi_check_object_type_tag(_env, _value, type_tag, &result);
-  NAPI_THROW_IF_FAILED(_env, status, false);
-  return result;
-}
 #endif  // NAPI_VERSION >= 8
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -1706,11 +1720,11 @@ inline External<T> External<T>::New(napi_env env,
 }
 
 template <typename T>
-inline External<T>::External() : Value() {}
+inline External<T>::External() : TypeTaggable() {}
 
 template <typename T>
 inline External<T>::External(napi_env env, napi_value value)
-    : Value(env, value) {}
+    : TypeTaggable(env, value) {}
 
 template <typename T>
 inline T* External<T>::Data() const {

napi.h

@@ -714,8 +714,19 @@ class Symbol : public Name {
          napi_value value);  ///< Wraps a Node-API value primitive.
 };
 
+class TypeTaggable : public Value {
+ public:
+#if NAPI_VERSION >= 8
+  void TypeTag(const napi_type_tag* type_tag) const;
+  bool CheckTypeTag(const napi_type_tag* type_tag) const;
+#endif  // NAPI_VERSION >= 8
+ protected:
+  TypeTaggable();
+  TypeTaggable(napi_env env, napi_value value);
+};
+
 /// A JavaScript object value.
-class Object : public Value {
+class Object : public TypeTaggable {
  public:
   /// Enables property and element assignments using indexing syntax.
   ///
@@ -991,14 +1002,11 @@ class Object : public Value {
   /// See
   /// https://tc39.es/ecma262/#sec-proxy-object-internal-methods-and-internal-slots-getprototypeof
   MaybeOrValue<bool> Seal() const;
-
-  void TypeTag(const napi_type_tag* type_tag) const;
-  bool CheckTypeTag(const napi_type_tag* type_tag) const;
 #endif  // NAPI_VERSION >= 8
 };
 
 template <typename T>
-class External : public Value {
+class External : public TypeTaggable {
  public:
   static External New(napi_env env, T* data);
 

test/binding.cc

@@ -76,7 +76,7 @@ Object InitVersionManagement(Env env);
 Object InitThunkingManual(Env env);
 #if (NAPI_VERSION > 7)
 Object InitObjectFreezeSeal(Env env);
-Object InitObjectTypeTag(Env env);
+Object InitTypeTaggable(Env env);
 #endif
 
 #if defined(NODE_ADDON_API_ENABLE_MAYBE)
@@ -169,7 +169,7 @@ Object Init(Env env, Object exports) {
   exports.Set("thunking_manual", InitThunkingManual(env));
 #if (NAPI_VERSION > 7)
   exports.Set("object_freeze_seal", InitObjectFreezeSeal(env));
-  exports.Set("object_type_tag", InitObjectTypeTag(env));
+  exports.Set("type_taggable", InitTypeTaggable(env));
 #endif
 
 #if defined(NODE_ADDON_API_ENABLE_MAYBE)

test/binding.gyp

@@ -48,7 +48,6 @@
         'object/has_property.cc',
         'object/object.cc',
         'object/object_freeze_seal.cc',
-        'object/object_type_tag.cc',
         'object/set_property.cc',
         'object/subscript_operator.cc',
         'promise.cc',
@@ -60,6 +59,7 @@
         'threadsafe_function/threadsafe_function_sum.cc',
         'threadsafe_function/threadsafe_function_unref.cc',
         'threadsafe_function/threadsafe_function.cc',
+        'type_taggable.cc',
         'typed_threadsafe_function/typed_threadsafe_function_ctx.cc',
         'typed_threadsafe_function/typed_threadsafe_function_existing_tsfn.cc',
         'typed_threadsafe_function/typed_threadsafe_function_ptr.cc',

test/index.js

@@ -134,7 +134,7 @@ if (majorNodeVersion < 12 && !filterConditionsProvided) {
 
 if (napiVersion < 8 && !filterConditionsProvided) {
   testModules.splice(testModules.indexOf('object/object_freeze_seal'), 1);
-  testModules.splice(testModules.indexOf('object/object_type_tag'), 1);
+  testModules.splice(testModules.indexOf('type_taggable'), 1);
 }
 
 (async function () {