- Add regression test case for dartbug.com/5546.

runtime/vm/object_test.cc

 // Copyright (c) 2012, 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 "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/bigint_operations.h"
 #include "vm/isolate.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
@@ skipping 2961 matching lines @@
     value ^= OneByteString::null();
   }
   isolate->heap()->CollectAllGarbage();
   // Weak property key and value should survive due to cross-generation
   // pointers.
   EXPECT(weak.key() != Object::null());
   EXPECT(weak.value() != Object::null());
 }
 
 
+TEST_CASE(WeakProperty_PreserveRecurse) {
+  // This used to end in an infinite recursion. Caused by scavenging the weak
+  // property before scavenging the key.
+  Isolate* isolate = Isolate::Current();
+  WeakProperty& weak = WeakProperty::Handle();
+  Array& arr = Array::Handle(Array::New(1));
+  {
+    HANDLESCOPE(isolate);
+    OneByteString& key = OneByteString::Handle();
+    key ^= OneByteString::New("key");
+    arr.SetAt(0, key);
+    OneByteString& value = OneByteString::Handle();
+    value ^= OneByteString::New("value");
+    weak ^= WeakProperty::New();
+    weak.set_key(key);
+    weak.set_value(value);
+  }
+  isolate->heap()->CollectAllGarbage();
+  EXPECT(weak.key() != Object::null());
+  EXPECT(weak.value() != Object::null());
+}
+
+
 TEST_CASE(WeakProperty_PreserveOne_NewSpace) {
   Isolate* isolate = Isolate::Current();
   WeakProperty& weak = WeakProperty::Handle();
   OneByteString& key = OneByteString::Handle();
   key ^= OneByteString::New("key");
   {
     HANDLESCOPE(isolate);
     OneByteString& value = OneByteString::Handle();
     value ^= OneByteString::New("value");
     weak ^= WeakProperty::New();
@@ skipping 228 matching lines @@
   isolate->heap()->CollectAllGarbage();
   EXPECT(weak1.key() == Object::null());
   EXPECT(weak1.value() == Object::null());
   EXPECT(weak2.key() == Object::null());
   EXPECT(weak2.value() == Object::null());
 }
 
 #endif  // defined(TARGET_ARCH_IA32) || defined(TARGET_ARCH_X64).
 
 }  // namespace dart