Introduce NanGlobal

nodejs · Jul 4, 2015 · 4408da1 · 4408da1
1 parent 7fed696
commit 4408da1
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Showing 3 changed files with 133 additions and 5 deletions.
diff --git a/nan_persistent_12_inl.h b/nan_persistent_12_inl.h
@@ -55,4 +55,75 @@ template<typename T, typename M> class NanPersistent :
   }
 };
 
+#if defined(V8_MAJOR_VERSION) && (V8_MAJOR_VERSION > 4 ||                      \
+  (V8_MAJOR_VERSION == 4 && defined(V8_MINOR_VERSION) && V8_MINOR_VERSION >= 3))
+template<typename T>
+class NanGlobal : public v8::Global<T> {
+ public:
+  NAN_INLINE NanGlobal() : v8::Global<T>() {}
+
+  template<typename S> NAN_INLINE NanGlobal(v8::Handle<S> that) :
+    v8::Global<T>(v8::Isolate::GetCurrent(), that) {}
+
+  template<typename S>
+  NAN_INLINE NanGlobal(const v8::PersistentBase<S> &that) :
+      v8::Global<S>(v8::Isolate::GetCurrent(), that) {}
+
+  NAN_INLINE void Reset() { v8::PersistentBase<T>::Reset(); }
+
+  template <typename S>
+  NAN_INLINE void Reset(const v8::Handle<S> &other) {
+    v8::PersistentBase<T>::Reset(v8::Isolate::GetCurrent(), other);
+  }
+
+  template <typename S>
+  NAN_INLINE void Reset(const v8::PersistentBase<S> &other) {
+    v8::PersistentBase<T>::Reset(v8::Isolate::GetCurrent(), other);
+  }
+
+  template<typename P>
+  NAN_INLINE void SetWeak(
+    P *parameter
+    , typename NanWeakCallbackInfo<P>::Callback callback
+    , NanWeakCallbackType type) {
+    reinterpret_cast<NanPersistent<T>*>(this)->SetWeak(
+        parameter, callback, type);
+  }
+};
+#else
+template<typename T>
+class NanGlobal : public v8::UniquePersistent<T> {
+ public:
+  NAN_INLINE NanGlobal() : v8::UniquePersistent<T>() {}
+
+  template<typename S> NAN_INLINE NanGlobal(v8::Handle<S> that) :
+    v8::UniquePersistent<T>(v8::Isolate::GetCurrent(), that) {}
+
+  template<typename S>
+  NAN_INLINE NanGlobal(const v8::PersistentBase<S> &that) :
+      v8::UniquePersistent<S>(v8::Isolate::GetCurrent(), that) {}
+
+  NAN_INLINE void Reset() { v8::PersistentBase<T>::Reset(); }
+
+  template <typename S>
+  NAN_INLINE void Reset(const v8::Handle<S> &other) {
+    v8::PersistentBase<T>::Reset(v8::Isolate::GetCurrent(), other);
+  }
+
+  template <typename S>
+  NAN_INLINE void Reset(const v8::PersistentBase<S> &other) {
+    v8::PersistentBase<T>::Reset(v8::Isolate::GetCurrent(), other);
+  }
+
+  template<typename P>
+  NAN_INLINE void SetWeak(
+    P *parameter
+    , typename NanWeakCallbackInfo<P>::Callback callback
+    , NanWeakCallbackType type) {
+    reinterpret_cast<NanPersistent<T>*>(this)->SetWeak(
+        parameter, callback, type);
+  }
+};
+#endif
+
 #endif  // NAN_PERSISTENT_12_INL_H_
diff --git a/nan_persistent_pre_12_inl.h b/nan_persistent_pre_12_inl.h
@@ -14,6 +14,7 @@ class NanPersistentBase {
   v8::Persistent<T> persistent;
   template<typename U, typename M>
   friend v8::Local<U> NanNew(const NanPersistent<U, M> &p);
+  template<typename S> friend class NanReturnValue;
 
  public:
   NAN_INLINE NanPersistentBase() :
@@ -97,7 +98,9 @@ class NanPersistentBase {
  private:
   NAN_INLINE explicit NanPersistentBase(v8::Persistent<T> that) :
       persistent(that) { }
+  NAN_INLINE explicit NanPersistentBase(T *val) : persistent(val) {}
   template<typename S, typename M> friend class NanPersistent;
+  template<typename S> friend class NanGlobal;
 };
 
 template<typename T>
@@ -177,4 +180,58 @@ template<typename T, typename M> class NanPersistent :
   }
 };
 
+template<typename T>
+class NanGlobal : public NanPersistentBase<T> {
+  struct RValue {
+    NAN_INLINE explicit RValue(NanGlobal* obj) : object(obj) {}
+    NanGlobal* object;
+  };
+
+ public:
+  NAN_INLINE NanGlobal() : NanPersistentBase<T>(0) { }
+
+  template <typename S>
+  NAN_INLINE NanGlobal(v8::Handle<S> that)
+      : NanPersistentBase<T>(v8::Persistent<T>::New(that)) {
+    TYPE_CHECK(T, S);
+  }
+
+  template <typename S>
+  NAN_INLINE NanGlobal(const NanPersistentBase<S> &that)
+    : NanPersistentBase<T>(that) {
+    TYPE_CHECK(T, S);
+  }
+  /**
+   * Move constructor.
+   */
+  NAN_INLINE NanGlobal(RValue rvalue)
+    : NanPersistentBase<T>(rvalue.object.persistent) {
+    rvalue.object->Reset();
+  }
+  NAN_INLINE ~NanGlobal() { this->Reset(); }
+  /**
+   * Move via assignment.
+   */
+  template<typename S>
+  NAN_INLINE NanGlobal &operator=(NanGlobal<S> rhs) {
+    TYPE_CHECK(T, S);
+    this->Reset(rhs.persistent);
+    rhs.Reset();
+    return *this;
+  }
+  /**
+   * Cast operator for moves.
+   */
+  NAN_INLINE operator RValue() { return RValue(this); }
+  /**
+   * Pass allows returning uniques from functions, etc.
+   */
+  NanGlobal Pass() { return NanGlobal(RValue(this)); }
+
+ private:
+  NanGlobal(NanGlobal &);
+  void operator=(NanGlobal &);
+  template<typename S> friend class NanReturnValue;
+};
+
 #endif  // NAN_PERSISTENT_PRE_12_INL_H_
diff --git a/test/cpp/returnvalue.cpp b/test/cpp/returnvalue.cpp
@@ -8,7 +8,7 @@
 
 #include <nan.h>
 
-NanPersistent<v8::Boolean> persistent;
+NanGlobal<v8::Boolean> global;
 
 NAN_METHOD(ReturnValue) {
   if (args.Length() == 1) {
@@ -26,12 +26,12 @@ NAN_METHOD(ReturnString) {
   NanReturnValue("yes, it works");
 }
 
-NAN_METHOD(ReturnPersistent) {
-  NanReturnValue(persistent);
+NAN_METHOD(ReturnGlobal) {
+  NanReturnValue(global);
 }
 
 void Init (v8::Handle<v8::Object> target) {
-  persistent.Reset(NanNew(true));
+  global.Reset(NanNew(true));
 
   target->Set(
       NanNew<v8::String>("r")
@@ -47,7 +47,7 @@ void Init (v8::Handle<v8::Object> target) {
   );
   target->Set(
       NanNew<v8::String>("q")
-    , NanNew<v8::FunctionTemplate>(ReturnPersistent)->GetFunction()
+    , NanNew<v8::FunctionTemplate>(ReturnGlobal)->GetFunction()
   );
 }