Introduce one way dependencies into object grouping.

test/cctest/test-api.cc

 // Copyright 2007-2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 32 matching lines @@
 static const bool kLogThreading = true;
 
 static bool IsNaN(double x) {
 #ifdef WIN32
   return _isnan(x);
 #else
   return isnan(x);
 #endif
 }
 
+using ::v8::AccessorInfo;
+using ::v8::Context;
+using ::v8::Extension;
+using ::v8::Function;
+using ::v8::HandleScope;
+using ::v8::Local;
+using ::v8::Object;
 using ::v8::ObjectTemplate;
+using ::v8::Persistent;
+using ::v8::Script;
+using ::v8::String;
 using ::v8::Value;
-using ::v8::Context;
-using ::v8::Local;
-using ::v8::String;
-using ::v8::Script;
-using ::v8::Function;
-using ::v8::AccessorInfo;
-using ::v8::Extension;
+using ::v8::V8;
 
 namespace i = ::i;
 
 
 static void ExpectString(const char* code, const char* expected) {
   Local<Value> result = CompileRun(code);
   CHECK(result->IsString());
   String::AsciiValue ascii(result);
   CHECK_EQ(expected, *ascii);
 }
@@ skipping 1710 matching lines @@
   {
     v8::HandleScope scope;
     Local<String> str = v8_str("str");
     global = v8::Persistent<String>::New(str);
   }
   CHECK_EQ(global->Length(), 3);
   global.Dispose();
 }
 
 
+static int NumberOfWeakCalls = 0;
+static void WeakPointerCallback(Persistent<Value> handle, void* id) {
+  CHECK_EQ(reinterpret_cast<void*>(1234), id);
+  NumberOfWeakCalls++;
+  handle.Dispose();
+}
+
+THREADED_TEST(ApiObjectGroups) {
+  HandleScope scope;
+  LocalContext env;
+
+  NumberOfWeakCalls = 0;
+
+  Persistent<Object> g1s1;
+  Persistent<Object> g1s2;
+  Persistent<Object> g1c1;
+  Persistent<Object> g2s1;
+  Persistent<Object> g2s2;
+  Persistent<Object> g2c1;
+
+  {
+    HandleScope scope;
+    g1s1 = Persistent<Object>::New(Object::New());
+    g1s2 = Persistent<Object>::New(Object::New());
+    g1c1 = Persistent<Object>::New(Object::New());
+    g1s1.MakeWeak(reinterpret_cast<void*>(1234), &WeakPointerCallback);
+    g1s2.MakeWeak(reinterpret_cast<void*>(1234), &WeakPointerCallback);
+    g1c1.MakeWeak(reinterpret_cast<void*>(1234), &WeakPointerCallback);
+
+    g2s1 = Persistent<Object>::New(Object::New());
+    g2s2 = Persistent<Object>::New(Object::New());
+    g2c1 = Persistent<Object>::New(Object::New());
+    g2s1.MakeWeak(reinterpret_cast<void*>(1234), &WeakPointerCallback);
+    g2s2.MakeWeak(reinterpret_cast<void*>(1234), &WeakPointerCallback);
+    g2c1.MakeWeak(reinterpret_cast<void*>(1234), &WeakPointerCallback);
+  }
+
+  Persistent<Object> root = Persistent<Object>::New(g1s1);  // make a root.
+
+  // Connect group 1 and 2, make a cycle.
+  CHECK(g1s2->Set(0, g2s2));
+  CHECK(g2s1->Set(0, g1s1));
+
+  {
+    Persistent<Value> g1_objects[] = { g1s1, g1s2 };
+    Persistent<Value> g1_children[] = { g1c1 };
+    Persistent<Value> g2_objects[] = { g2s1, g2s2 };
+    Persistent<Value> g2_children[] = { g2c1 };
+    V8::AddObjectGroup(g1_objects, 2);
+    V8::AddImplicitRefGroup(g1s1, g1_children, 1);
+    V8::AddObjectGroup(g2_objects, 2);
+    V8::AddImplicitRefGroup(g2s2, g2_children, 1);

[Vitaly Repeshko, 2011/03/15 18:45:35]

It would be interesting to test longer chains of implicit references.

+  }
+  // Do a full GC
+  i::Heap::CollectGarbage(i::OLD_POINTER_SPACE);
+
+  // All object should be alive.
+  CHECK_EQ(0, NumberOfWeakCalls);
+
+  // Weaken the root.
+  root.MakeWeak(reinterpret_cast<void*>(1234), &WeakPointerCallback);
+  // But make children strong roots---all the objects (except for children)
+  // should be collectable now.
+  g1c1.ClearWeak();
+  g2c1.ClearWeak();
+
+  // Groups are deleted, rebuild groups.
+  {
+    Persistent<Value> g1_objects[] = { g1s1, g1s2 };
+    Persistent<Value> g1_children[] = { g1c1 };
+    Persistent<Value> g2_objects[] = { g2s1, g2s2 };
+    Persistent<Value> g2_children[] = { g2c1 };
+    V8::AddObjectGroup(g1_objects, 2);
+    V8::AddImplicitRefGroup(g1s1, g1_children, 1);
+    V8::AddObjectGroup(g2_objects, 2);
+    V8::AddImplicitRefGroup(g2s2, g2_children, 1);
+  }
+
+  i::Heap::CollectGarbage(i::OLD_POINTER_SPACE);
+
+  // All objects should be gone. 5 global handles in total.
+  CHECK_EQ(5, NumberOfWeakCalls);
+
+  // And now make children weak again and collect them.
+  g1c1.MakeWeak(reinterpret_cast<void*>(1234), &WeakPointerCallback);
+  g2c1.MakeWeak(reinterpret_cast<void*>(1234), &WeakPointerCallback);
+
+  i::Heap::CollectGarbage(i::OLD_POINTER_SPACE);
+  CHECK_EQ(7, NumberOfWeakCalls);
+}
+
+
 THREADED_TEST(ScriptException) {
   v8::HandleScope scope;
   LocalContext env;
   Local<Script> script = Script::Compile(v8_str("throw 'panama!';"));
   v8::TryCatch try_catch;
   Local<Value> result = script->Run();
   CHECK(result.IsEmpty());
   CHECK(try_catch.HasCaught());
   String::AsciiValue exception_value(try_catch.Exception());
   CHECK_EQ(*exception_value, "panama!");
@@ skipping 11126 matching lines @@
   v8::Handle<v8::Function> define_property =
       CompileRun("(function() {"
                  "  Object.defineProperty("
                  "    this,"
                  "    1,"
                  "    { configurable: true, enumerable: true, value: 3 });"
                  "})").As<Function>();
   context->DetachGlobal();
   define_property->Call(proxy, 0, NULL);
 }