n-api: napi_is_construct_call->napi_get_new_target

Sampson Gao · jasnell · commit a2d340fb0083 · 2017-09-20T09:23:01.000-07:00
Remove napi_is_construct_call and introduce napi_get_new_target. PR-URL: #14698 Reviewed-By: Jason Ginchereau <jasongin@microsoft.com> Reviewed-By: Colin Ihrig <cjihrig@gmail.com> Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com> Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Kyle Farnung <kfarnung@microsoft.com>
diff --git a/doc/api/n-api.md b/doc/api/n-api.md
@@ -2918,25 +2918,24 @@ Returns `napi_ok` if the API succeeded.
 This method is used within a callback function to retrieve details about the
 call like the arguments and the `this` pointer from a given callback info.
 
-### *napi_is_construct_call*
+### *napi_get_new_target*
 <!-- YAML
-added: v8.0.0
+added: REPLACEME
 -->
 ```C
-napi_status napi_is_construct_call(napi_env env,
-                                   napi_callback_info cbinfo,
-                                   bool* result)
+napi_status napi_get_new_target(napi_env env,
+                                napi_callback_info cbinfo,
+                                napi_value* result)
 ```
 
 - `[in] env`: The environment that the API is invoked under.
 - `[in] cbinfo`: The callback info passed into the callback function.
-- `[out] result`: Whether the native function is being invoked as
-a constructor call.
+- `[out] result`: The `new.target` of the constructor call.
 
 Returns `napi_ok` if the API succeeded.
 
-This API checks if the the current callback was due to a
-consructor call.
+This API returns the `new.target` of the constructor call. If the current
+callback is not a constructor call, the result is `nullptr`.
 
 ### *napi_new_instance*
 <!-- YAML
diff --git a/src/node_api.cc b/src/node_api.cc
@@ -446,7 +446,7 @@ class CallbackWrapper {
   CallbackWrapper(napi_value this_arg, size_t args_length, void* data)
       : _this(this_arg), _args_length(args_length), _data(data) {}
 
-  virtual bool IsConstructCall() = 0;
+  virtual napi_value NewTarget() = 0;
   virtual void Args(napi_value* buffer, size_t bufferlength) = 0;
   virtual void SetReturnValue(napi_value value) = 0;
 
@@ -475,8 +475,7 @@ class CallbackWrapperBase : public CallbackWrapper {
                 ->Value();
   }
 
-  /*virtual*/
-  bool IsConstructCall() override { return false; }
+  napi_value NewTarget() override { return nullptr; }
 
  protected:
   void InvokeCallback() {
@@ -524,8 +523,13 @@ class FunctionCallbackWrapper
       const v8::FunctionCallbackInfo<v8::Value>& cbinfo)
       : CallbackWrapperBase(cbinfo, cbinfo.Length()) {}
 
-  /*virtual*/
-  bool IsConstructCall() override { return _cbinfo.IsConstructCall(); }
+  napi_value NewTarget() override {
+    if (_cbinfo.IsConstructCall()) {
+      return v8impl::JsValueFromV8LocalValue(_cbinfo.NewTarget());
+    } else {
+      return nullptr;
+    }
+  }
 
   /*virtual*/
   void Args(napi_value* buffer, size_t buffer_length) override {
@@ -1874,18 +1878,17 @@ napi_status napi_get_cb_info(
   return napi_clear_last_error(env);
 }
 
-napi_status napi_is_construct_call(napi_env env,
-                                   napi_callback_info cbinfo,
-                                   bool* result) {
-  // Omit NAPI_PREAMBLE and GET_RETURN_STATUS because no V8 APIs are called.
+napi_status napi_get_new_target(napi_env env,
+                                napi_callback_info cbinfo,
+                                napi_value* result) {
   CHECK_ENV(env);
   CHECK_ARG(env, cbinfo);
   CHECK_ARG(env, result);
 
   v8impl::CallbackWrapper* info =
       reinterpret_cast<v8impl::CallbackWrapper*>(cbinfo);
 
-  *result = info->IsConstructCall();
+  *result = info->NewTarget();
   return napi_clear_last_error(env);
 }
 
diff --git a/src/node_api.h b/src/node_api.h
@@ -340,9 +340,9 @@ NAPI_EXTERN napi_status napi_get_cb_info(
     napi_value* this_arg,  // [out] Receives the JS 'this' arg for the call
     void** data);          // [out] Receives the data pointer for the callback.
 
-NAPI_EXTERN napi_status napi_is_construct_call(napi_env env,
-                                               napi_callback_info cbinfo,
-                                               bool* result);
+NAPI_EXTERN napi_status napi_get_new_target(napi_env env,
+                                            napi_callback_info cbinfo,
+                                            napi_value* result);
 NAPI_EXTERN napi_status
 napi_define_class(napi_env env,
                   const char* utf8name,
diff --git a/test/addons-napi/6_object_wrap/myobject.cc b/test/addons-napi/6_object_wrap/myobject.cc
@@ -32,8 +32,9 @@ void MyObject::Init(napi_env env, napi_value exports) {
 }
 
 napi_value MyObject::New(napi_env env, napi_callback_info info) {
-  bool is_constructor;
-  NAPI_CALL(env, napi_is_construct_call(env, info, &is_constructor));
+  napi_value new_target;
+  NAPI_CALL(env, napi_get_new_target(env, info, &new_target));
+  bool is_constructor = (new_target != nullptr);
 
   size_t argc = 1;
   napi_value args[1];
