Allow null other.m_parent in TraceWrapperMember::operator= if other is nullptr.

third_party/WebKit/Source/bindings/core/v8/TraceWrapperMemberTest.cpp

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "bindings/core/v8/TraceWrapperMember.h"
 
 #include "core/testing/DeathAwareScriptWrappable.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace blink {
 
+namespace {
+
+using Wrapper = TraceWrapperMember<DeathAwareScriptWrappable>;
+
+}  // namespace
+
 TEST(TraceWrapperMemberTest, HeapVectorSwap) {
-  typedef TraceWrapperMember<DeathAwareScriptWrappable> Wrapper;
-
   HeapVector<Wrapper> vector1;
   DeathAwareScriptWrappable* parent1 = DeathAwareScriptWrappable::create();
   DeathAwareScriptWrappable* child1 = DeathAwareScriptWrappable::create();
   vector1.push_back(Wrapper(parent1, child1));
 
   HeapVector<Wrapper> vector2;
   DeathAwareScriptWrappable* parent2 = DeathAwareScriptWrappable::create();
   DeathAwareScriptWrappable* child2 = DeathAwareScriptWrappable::create();
   vector2.push_back(Wrapper(parent2, child2));
 
   swap(vector1, vector2, parent1, parent2);
   EXPECT_EQ(parent1, vector1.front().parent());
   EXPECT_EQ(parent2, vector2.front().parent());
 }
 
 TEST(TraceWrapperMemberTest, HeapVectorSwap2) {
-  typedef TraceWrapperMember<DeathAwareScriptWrappable> Wrapper;
-
   HeapVector<Wrapper> vector1;
   DeathAwareScriptWrappable* parent1 = DeathAwareScriptWrappable::create();
   DeathAwareScriptWrappable* child1 = DeathAwareScriptWrappable::create();
   vector1.push_back(Wrapper(parent1, child1));
 
   HeapVector<Member<DeathAwareScriptWrappable>> vector2;
   DeathAwareScriptWrappable* child2 = DeathAwareScriptWrappable::create();
   vector2.push_back(child2);
 
   swap(vector1, vector2, parent1);
   EXPECT_EQ(1u, vector1.size());
   EXPECT_EQ(child2, vector1.front().get());
   EXPECT_EQ(parent1, vector1.front().parent());
   EXPECT_EQ(1u, vector2.size());
   EXPECT_EQ(child1, vector2.front().get());
 }
 
+TEST(TraceWrapperMemberTest, HeapHashSet) {
+  HeapHashSet<Wrapper> set;
+  DeathAwareScriptWrappable* parent = DeathAwareScriptWrappable::create();
+
+  // Loop enough so that underlying HashTable will rehash several times.
+  for (int i = 1; i < 10000; ++i) {
+    DeathAwareScriptWrappable* child = DeathAwareScriptWrappable::create();
+    set.insert(Wrapper(parent, child));
+  }
+  EXPECT_EQ(9999u, set.size());
+
+  HeapHashSet<Wrapper> set2;
+  swap(set, set2);
+  EXPECT_EQ(0u, set.size());
+  EXPECT_EQ(9999u, set2.size());
+
+  for (int i = 1; i < 10000; ++i) {
+    auto wrapper = set2.takeAny();
+    EXPECT_EQ(wrapper.parent(), parent);
+  }
+
+  EXPECT_EQ(0u, set2.size());
+}
+
+TEST(TraceWrapperMemberTest, HeapHashMapValue) {
+  HeapHashMap<int, Wrapper> map;
+  DeathAwareScriptWrappable* parent = DeathAwareScriptWrappable::create();
+
+  // Loop enough so that underlying HashTable will rehash several times.
+  for (int i = 1; i < 10000; ++i) {
+    DeathAwareScriptWrappable* child = DeathAwareScriptWrappable::create();
+    map.insert(i, Wrapper(parent, child));
+  }
+  EXPECT_EQ(9999u, map.size());
+
+  for (int i = 1; i < 10000; ++i) {
+    auto wrapper = map.take(i);
+    EXPECT_EQ(wrapper.parent(), parent);
+  }
+
+  EXPECT_EQ(0u, map.size());
+}
+
 }  // namespace blink