add hinted option

nodejs · Apr 13, 2020 · f8d6482 · f8d6482
1 parent 131e252
commit f8d6482
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Showing 3 changed files with 31 additions and 4 deletions.
diff --git a/napi-inl.h b/napi-inl.h
@@ -345,6 +345,11 @@ inline T* Env::GetInstanceData() {
 template <typename T> void Env::DefaultFini(Env, T* data) {
   delete data;
 }
+
+template <typename DataType, typename HintType>
+void Env::DefaultFiniWithHint(Env, DataType* data, HintType*) {
+  delete data;
+}
 #endif  // NAPI_VERSION > 5
 
 ////////////////////////////////////////////////////////////////////////////////

diff --git a/napi.h b/napi.h
@@ -200,6 +200,14 @@ namespace Napi {
     template <typename T> using Finalizer = void (*)(Env, T*);
     template <typename T, Finalizer<T> fini = Env::DefaultFini<T>>
     void SetInstanceData(T* data);
+
+    template <typename DataType, typename HintType>
+    using FinalizerWithHint = void (*)(Env, DataType*, HintType*);
+    template <typename DataType,
+              typename HintType,
+              FinalizerWithHint<DataType, HintType> fini =
+                Env::DefaultFiniWithHint<DataType, HintType>>
+    void SetInstanceData(DataType* data, HintType* hint);
 #endif  // NAPI_VERSION > 5
 
   private:

diff --git a/test/addon_data.cc b/test/addon_data.cc
@@ -49,15 +49,22 @@ class Addon {
     info.Env().GetInstanceData<Addon>()->verbose = info[0].As<Napi::Boolean>();
   }
 
-  Addon(Napi::Env env): VerboseIndicator(VerboseIndicator::Init(env)) {}
+  Addon(Napi::Env env, uint32_t hint = 0) :
+      hint(hint), VerboseIndicator(VerboseIndicator::Init(env)) {}
   ~Addon() {
     if (verbose) {
       fprintf(stderr, "addon_data: Addon::~Addon\n");
+      if (hint > 0) {
+        fprintf(stderr, "hint: %u\n", hint);
+      }
     }
   }
 
-  static Napi::Object Init(Napi::Env env) {
-    env.SetInstanceData(new Addon(env));
+  static Napi::Object Init(Napi::Env env, Napi::Value hint) {
+    if (!hint.IsNumber()) {
+      NAPI_THROW(Napi::Error::New(env, "Expected number"), Napi::Object());
+    }
+    env.SetInstanceData(new Addon(env, hint.As<Napi::Number>()));
     Napi::Object result = Napi::Object::New(env);
     result.DefineProperties({
       Napi::PropertyDescriptor::Accessor<Getter, Setter>("verbose"),
@@ -68,10 +75,17 @@ class Addon {
 
  private:
   bool verbose = false;
+  uint32_t hint = 0;
   Napi::FunctionReference VerboseIndicator;
 };
 
+// We use an addon factory so we can cover both the case where there is an
+// instance data hint and the case where there isn't.
+static Napi::Value AddonFactory(const Napi::CallbackInfo& info) {
+  return Addon::Init(info.Env(), info[0]);
+}
+
 Napi::Object InitAddonData(Napi::Env env) {
-  return Addon::Init(env);
+  return Napi::Function::New(env, AddonFactory);
 }
 #endif  // (NAPI_VERSION > 5)