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Diffstat (limited to 'absl/random/internal/salted_seed_seq_test.cc')
-rw-r--r-- | absl/random/internal/salted_seed_seq_test.cc | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/absl/random/internal/salted_seed_seq_test.cc b/absl/random/internal/salted_seed_seq_test.cc new file mode 100644 index 00000000..0bf19a63 --- /dev/null +++ b/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 |