1 files changed, 168 insertions, 0 deletions
diff --git a/third_party/abseil_cpp/absl/random/internal/salted_seed_seq_test.cc b/third_party/abseil_cpp/absl/random/internal/salted_seed_seq_test.cc
new file mode 100644
index 0000000000..0bf19a63ef
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+++ b/third_party/abseil_cpp/absl/random/internal/salted_seed_seq_test.cc
@@ -0,0 +1,168 @@
+// Copyright 2017 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
+//
+//      https://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/random/internal/salted_seed_seq.h"
+
+#include <iterator>
+#include <random>
+#include <utility>
+#include <vector>
+
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+
+using absl::random_internal::GetSaltMaterial;
+using absl::random_internal::MakeSaltedSeedSeq;
+using absl::random_internal::SaltedSeedSeq;
+using testing::Eq;
+using testing::Pointwise;
+
+namespace {
+
+template <typename Sseq>
+void ConformsToInterface() {
+  // Check that the SeedSequence can be default-constructed.
+  { Sseq default_constructed_seq; }
+  // Check that the SeedSequence can be constructed with two iterators.
+  {
+    uint32_t init_array[] = {1, 3, 5, 7, 9};
+    Sseq iterator_constructed_seq(std::begin(init_array), std::end(init_array));
+  }
+  // Check that the SeedSequence can be std::initializer_list-constructed.
+  { Sseq list_constructed_seq = {1, 3, 5, 7, 9, 11, 13}; }
+  // Check that param() and size() return state provided to constructor.
+  {
+    uint32_t init_array[] = {1, 2, 3, 4, 5};
+    Sseq seq(std::begin(init_array), std::end(init_array));
+    EXPECT_EQ(seq.size(), ABSL_ARRAYSIZE(init_array));
+
+    std::vector<uint32_t> state_vector;
+    seq.param(std::back_inserter(state_vector));
+
+    EXPECT_EQ(state_vector.size(), ABSL_ARRAYSIZE(init_array));
+    for (int i = 0; i < state_vector.size(); i++) {
+      EXPECT_EQ(state_vector[i], i + 1);
+    }
+  }
+  // Check for presence of generate() method.
+  {
+    Sseq seq;
+    uint32_t seeds[5];
+
+    seq.generate(std::begin(seeds), std::end(seeds));
+  }
+}
+
+TEST(SaltedSeedSeq, CheckInterfaces) {
+  // Control case
+  ConformsToInterface<std::seed_seq>();
+
+  // Abseil classes
+  ConformsToInterface<SaltedSeedSeq<std::seed_seq>>();
+}
+
+TEST(SaltedSeedSeq, CheckConstructingFromOtherSequence) {
+  std::vector<uint32_t> seed_values(10, 1);
+  std::seed_seq seq(seed_values.begin(), seed_values.end());
+  auto salted_seq = MakeSaltedSeedSeq(std::move(seq));
+
+  EXPECT_EQ(seq.size(), salted_seq.size());
+
+  std::vector<uint32_t> param_result;
+  seq.param(std::back_inserter(param_result));
+
+  EXPECT_EQ(seed_values, param_result);
+}
+
+TEST(SaltedSeedSeq, SaltedSaltedSeedSeqIsNotDoubleSalted) {
+  uint32_t init[] = {1, 3, 5, 7, 9};
+
+  std::seed_seq seq(std::begin(init), std::end(init));
+
+  // The first salting.
+  SaltedSeedSeq<std::seed_seq> salted_seq = MakeSaltedSeedSeq(std::move(seq));
+  uint32_t a[16];
+  salted_seq.generate(std::begin(a), std::end(a));
+
+  // The second salting.
+  SaltedSeedSeq<std::seed_seq> salted_salted_seq =
+      MakeSaltedSeedSeq(std::move(salted_seq));
+  uint32_t b[16];
+  salted_salted_seq.generate(std::begin(b), std::end(b));
+
+  // ... both should be equal.
+  EXPECT_THAT(b, Pointwise(Eq(), a)) << "a[0] " << a[0];
+}
+
+TEST(SaltedSeedSeq, SeedMaterialIsSalted) {
+  const size_t kNumBlocks = 16;
+
+  uint32_t seed_material[kNumBlocks];
+  std::random_device urandom{"/dev/urandom"};
+  for (uint32_t& seed : seed_material) {
+    seed = urandom();
+  }
+
+  std::seed_seq seq(std::begin(seed_material), std::end(seed_material));
+  SaltedSeedSeq<std::seed_seq> salted_seq(std::begin(seed_material),
+                                          std::end(seed_material));
+
+  bool salt_is_available = GetSaltMaterial().has_value();
+
+  // If salt is available generated sequence should be different.
+  if (salt_is_available) {
+    uint32_t outputs[kNumBlocks];
+    uint32_t salted_outputs[kNumBlocks];
+
+    seq.generate(std::begin(outputs), std::end(outputs));
+    salted_seq.generate(std::begin(salted_outputs), std::end(salted_outputs));
+
+    EXPECT_THAT(outputs, Pointwise(testing::Ne(), salted_outputs));
+  }
+}
+
+TEST(SaltedSeedSeq, GenerateAcceptsDifferentTypes) {
+  const size_t kNumBlocks = 4;
+
+  SaltedSeedSeq<std::seed_seq> seq({1, 2, 3});
+
+  uint32_t expected[kNumBlocks];
+  seq.generate(std::begin(expected), std::end(expected));
+
+  // 32-bit outputs
+  {
+    unsigned long seed_material[kNumBlocks];  // NOLINT(runtime/int)
+    seq.generate(std::begin(seed_material), std::end(seed_material));
+    EXPECT_THAT(seed_material, Pointwise(Eq(), expected));
+  }
+  {
+    unsigned int seed_material[kNumBlocks];  // NOLINT(runtime/int)
+    seq.generate(std::begin(seed_material), std::end(seed_material));
+    EXPECT_THAT(seed_material, Pointwise(Eq(), expected));
+  }
+
+  // 64-bit outputs.
+  {
+    uint64_t seed_material[kNumBlocks];
+    seq.generate(std::begin(seed_material), std::end(seed_material));
+    EXPECT_THAT(seed_material, Pointwise(Eq(), expected));
+  }
+  {
+    int64_t seed_material[kNumBlocks];
+    seq.generate(std::begin(seed_material), std::end(seed_material));
+    EXPECT_THAT(seed_material, Pointwise(Eq(), expected));
+  }
+}
+
+}  // namespace