Provide API support for weak handles and post-mortem finalization.

runtime/vm/dart_api_impl_test.cc

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "include/dart_api.h"
 
 #include "vm/assert.h"
 #include "vm/dart_api_impl.h"
 #include "vm/dart_api_state.h"
 #include "vm/thread.h"
@@ skipping 813 matching lines @@
   EXPECT(!Dart_IsNull(weak_old_ref));
 
   // garbage collect old space again
   Isolate::Current()->heap()->CollectGarbage(Heap::kOld);
 
   // weak ref to old space object should now be cleared
   EXPECT_VALID(weak_new_ref);
   EXPECT(Dart_IsNull(weak_new_ref));
   EXPECT_VALID(weak_old_ref);
   EXPECT(Dart_IsNull(weak_old_ref));
+
+  Dart_DeletePersistentHandle(weak_new_ref);
+  Dart_DeletePersistentHandle(weak_old_ref);
+}
+
+
+static void WeakPersistentHandlePeerFinalizer(void* peer) {
+  *static_cast<int*>(peer) = 42;
+}
+
+
+TEST_CASE(WeakPersistentHandleCallback) {
+  Dart_Handle weak_ref = Dart_Null();
+  EXPECT(Dart_IsNull(weak_ref));
+  int* peer = new int();
+  {
+    Dart_EnterScope();
+    Dart_Handle obj = Dart_NewString("new string");
+    EXPECT_VALID(obj);
+    weak_ref = Dart_NewWeakPersistentHandle(obj, peer,
+                                            WeakPersistentHandlePeerFinalizer);
+    Dart_ExitScope();
+  }
+  EXPECT_VALID(weak_ref);
+  EXPECT(*peer == 0);
+  Isolate::Current()->heap()->CollectGarbage(Heap::kOld);
+  EXPECT(*peer == 0);
+  Isolate::Current()->heap()->CollectGarbage(Heap::kNew);
+  EXPECT(*peer == 42);
+  delete peer;
+  Dart_DeletePersistentHandle(weak_ref);
 }
 
 #endif
 
 
 // Unit test for creating multiple scopes and local handles within them.
 // Ensure that the local handles get all cleaned out when exiting the
 // scope.
 UNIT_TEST_CASE(LocalHandles) {
   TestCase::CreateTestIsolate();
@@ skipping 2127 matching lines @@
   // We should have received the expected number of interrupts.
   EXPECT_EQ(kInterruptCount, interrupt_count);
 
   // Give the spawned thread enough time to properly exit.
   Isolate::SetInterruptCallback(saved);
 }
 
 #endif  // TARGET_ARCH_IA32.
 
 }  // namespace dart