Export of internal Abseil changes.

--
4eacae3ff1b14b1d309e8092185bc10e8a6203cf by Derek Mauro <dmauro@google.com>:

Release SwissTable - a fast, efficient, cache-friendly hash table.

https://www.youtube.com/watch?v=ncHmEUmJZf4

PiperOrigin-RevId: 214816527

--
df8c3dfab3cfb2f4365909a84d0683b193cfbb11 by Derek Mauro <dmauro@google.com>:

Internal change

PiperOrigin-RevId: 214785288

--
1eabd5266bbcebc33eecc91e5309b751856a75c8 by Abseil Team <absl-team@google.com>:

Internal change

PiperOrigin-RevId: 214722931

--
2ebbfac950f83146b46253038e7dd7dcde9f2951 by Derek Mauro <dmauro@google.com>:

Internal change

PiperOrigin-RevId: 214701684
GitOrigin-RevId: 4eacae3ff1b14b1d309e8092185bc10e8a6203cf
Change-Id: I9ba64e395b22ad7863213d157b8019b082adc19d

absl/container/internal/node_hash_policy_test.cc

@@ -0,0 +1,67 @@
+// Copyright 2018 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "absl/container/internal/node_hash_policy.h"
+
+#include <memory>
+
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+#include "absl/container/internal/hash_policy_traits.h"
+
+namespace absl {
+namespace container_internal {
+namespace {
+
+using ::testing::Pointee;
+
+struct Policy : node_hash_policy<int&, Policy> {
+  using key_type = int;
+  using init_type = int;
+
+  template <class Alloc>
+  static int* new_element(Alloc* alloc, int value) {
+    return new int(value);
+  }
+
+  template <class Alloc>
+  static void delete_element(Alloc* alloc, int* elem) {
+    delete elem;
+  }
+};
+
+using NodePolicy = hash_policy_traits<Policy>;
+
+struct NodeTest : ::testing::Test {
+  std::allocator<int> alloc;
+  int n = 53;
+  int* a = &n;
+};
+
+TEST_F(NodeTest, ConstructDestroy) {
+  NodePolicy::construct(&alloc, &a, 42);
+  EXPECT_THAT(a, Pointee(42));
+  NodePolicy::destroy(&alloc, &a);
+}
+
+TEST_F(NodeTest, transfer) {
+  int s = 42;
+  int* b = &s;
+  NodePolicy::transfer(&alloc, &a, &b);
+  EXPECT_EQ(&s, a);
+}
+
+}  // namespace
+}  // namespace container_internal
+}  // namespace absl