Export of internal Abseil changes.

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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

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

Internal change

PiperOrigin-RevId: 214785288

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

Internal change

PiperOrigin-RevId: 214722931

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

Internal change

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

1 files changed, 126 insertions, 0 deletions

diff --git a/absl/container/flat_hash_set_test.cc b/absl/container/flat_hash_set_test.cc
new file mode 100644
index 000000000000..e52fd532cbee
--- /dev/null
+++ b/absl/container/flat_hash_set_test.cc
@@ -0,0 +1,126 @@
+// 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/flat_hash_set.h"
+
+#include <vector>
+
+#include "absl/container/internal/hash_generator_testing.h"
+#include "absl/container/internal/unordered_set_constructor_test.h"
+#include "absl/container/internal/unordered_set_lookup_test.h"
+#include "absl/container/internal/unordered_set_modifiers_test.h"
+#include "absl/memory/memory.h"
+#include "absl/strings/string_view.h"
+
+namespace absl {
+namespace container_internal {
+namespace {
+
+using ::absl::container_internal::hash_internal::Enum;
+using ::absl::container_internal::hash_internal::EnumClass;
+using ::testing::Pointee;
+using ::testing::UnorderedElementsAre;
+using ::testing::UnorderedElementsAreArray;
+
+template <class T>
+using Set =
+    absl::flat_hash_set<T, StatefulTestingHash, StatefulTestingEqual, Alloc<T>>;
+
+using SetTypes =
+    ::testing::Types<Set<int>, Set<std::string>, Set<Enum>, Set<EnumClass>>;
+
+INSTANTIATE_TYPED_TEST_CASE_P(FlatHashSet, ConstructorTest, SetTypes);
+INSTANTIATE_TYPED_TEST_CASE_P(FlatHashSet, LookupTest, SetTypes);
+INSTANTIATE_TYPED_TEST_CASE_P(FlatHashSet, ModifiersTest, SetTypes);
+
+TEST(FlatHashSet, EmplaceString) {
+  std::vector<std::string> v = {"a", "b"};
+  absl::flat_hash_set<absl::string_view> hs(v.begin(), v.end());
+  EXPECT_THAT(hs, UnorderedElementsAreArray(v));
+}
+
+TEST(FlatHashSet, BitfieldArgument) {
+  union {
+    int n : 1;
+  };
+  n = 0;
+  absl::flat_hash_set<int> s = {n};
+  s.insert(n);
+  s.insert(s.end(), n);
+  s.insert({n});
+  s.erase(n);
+  s.count(n);
+  s.prefetch(n);
+  s.find(n);
+  s.contains(n);
+  s.equal_range(n);
+}
+
+TEST(FlatHashSet, MergeExtractInsert) {
+  struct Hash {
+    size_t operator()(const std::unique_ptr<int>& p) const { return *p; }
+  };
+  struct Eq {
+    bool operator()(const std::unique_ptr<int>& a,
+                    const std::unique_ptr<int>& b) const {
+      return *a == *b;
+    }
+  };
+  absl::flat_hash_set<std::unique_ptr<int>, Hash, Eq> set1, set2;
+  set1.insert(absl::make_unique<int>(7));
+  set1.insert(absl::make_unique<int>(17));
+
+  set2.insert(absl::make_unique<int>(7));
+  set2.insert(absl::make_unique<int>(19));
+
+  EXPECT_THAT(set1, UnorderedElementsAre(Pointee(7), Pointee(17)));
+  EXPECT_THAT(set2, UnorderedElementsAre(Pointee(7), Pointee(19)));
+
+  set1.merge(set2);
+
+  EXPECT_THAT(set1, UnorderedElementsAre(Pointee(7), Pointee(17), Pointee(19)));
+  EXPECT_THAT(set2, UnorderedElementsAre(Pointee(7)));
+
+  auto node = set1.extract(absl::make_unique<int>(7));
+  EXPECT_TRUE(node);
+  EXPECT_THAT(node.value(), Pointee(7));
+  EXPECT_THAT(set1, UnorderedElementsAre(Pointee(17), Pointee(19)));
+
+  auto insert_result = set2.insert(std::move(node));
+  EXPECT_FALSE(node);
+  EXPECT_FALSE(insert_result.inserted);
+  EXPECT_TRUE(insert_result.node);
+  EXPECT_THAT(insert_result.node.value(), Pointee(7));
+  EXPECT_EQ(**insert_result.position, 7);
+  EXPECT_NE(insert_result.position->get(), insert_result.node.value().get());
+  EXPECT_THAT(set2, UnorderedElementsAre(Pointee(7)));
+
+  node = set1.extract(absl::make_unique<int>(17));
+  EXPECT_TRUE(node);
+  EXPECT_THAT(node.value(), Pointee(17));
+  EXPECT_THAT(set1, UnorderedElementsAre(Pointee(19)));
+
+  node.value() = absl::make_unique<int>(23);
+
+  insert_result = set2.insert(std::move(node));
+  EXPECT_FALSE(node);
+  EXPECT_TRUE(insert_result.inserted);
+  EXPECT_FALSE(insert_result.node);
+  EXPECT_EQ(**insert_result.position, 23);
+  EXPECT_THAT(set2, UnorderedElementsAre(Pointee(7), Pointee(23)));
+}
+
+}  // namespace
+}  // namespace container_internal
+}  // namespace absl