1 //
2 // Copyright 2018 The Abseil Authors.
3 //
4 // Licensed under the Apache License, Version 2.0 (the "License");
5 // you may not use this file except in compliance with the License.
6 // You may obtain a copy of the License at
7 //
8 // https://www.apache.org/licenses/LICENSE-2.0
9 //
10 // Unless required by applicable law or agreed to in writing, software
11 // distributed under the License is distributed on an "AS IS" BASIS,
12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 // See the License for the specific language governing permissions and
14 // limitations under the License.
15 //
16 #include "absl/random/bit_gen_ref.h"
17
18 #include <cstdint>
19 #include <random>
20 #include <vector>
21
22 #include "gmock/gmock.h"
23 #include "gtest/gtest.h"
24 #include "absl/base/config.h"
25 #include "absl/base/internal/fast_type_id.h"
26 #include "absl/random/internal/sequence_urbg.h"
27 #include "absl/random/random.h"
28
29 namespace absl {
30 ABSL_NAMESPACE_BEGIN
31
32 class ConstBitGen {
33 public:
34 // URBG interface
35 using result_type = absl::BitGen::result_type;
36
result_type(min)37 static constexpr result_type(min)() { return (absl::BitGen::min)(); }
result_type(max)38 static constexpr result_type(max)() { return (absl::BitGen::max)(); }
operator ()()39 result_type operator()() { return 1; }
40
41 // InvokeMock method
InvokeMock(base_internal::FastTypeIdType,void *,void * result)42 bool InvokeMock(base_internal::FastTypeIdType, void*, void* result) {
43 *static_cast<int*>(result) = 42;
44 return true;
45 }
46 };
47
48 namespace {
49
FnTest(absl::BitGenRef gen_ref)50 int FnTest(absl::BitGenRef gen_ref) { return absl::Uniform(gen_ref, 1, 7); }
51
52 template <typename T>
53 class BitGenRefTest : public testing::Test {};
54
55 using BitGenTypes =
56 ::testing::Types<absl::BitGen, absl::InsecureBitGen, std::mt19937,
57 std::mt19937_64, std::minstd_rand>;
58 TYPED_TEST_SUITE(BitGenRefTest, BitGenTypes);
59
TYPED_TEST(BitGenRefTest,BasicTest)60 TYPED_TEST(BitGenRefTest, BasicTest) {
61 TypeParam gen;
62 auto x = FnTest(gen);
63 EXPECT_NEAR(x, 4, 3);
64 }
65
TYPED_TEST(BitGenRefTest,Copyable)66 TYPED_TEST(BitGenRefTest, Copyable) {
67 TypeParam gen;
68 absl::BitGenRef gen_ref(gen);
69 FnTest(gen_ref); // Copy
70 }
71
TEST(BitGenRefTest,PassThroughEquivalence)72 TEST(BitGenRefTest, PassThroughEquivalence) {
73 // sequence_urbg returns 64-bit results.
74 absl::random_internal::sequence_urbg urbg(
75 {0x0003eb76f6f7f755ull, 0xFFCEA50FDB2F953Bull, 0xC332DDEFBE6C5AA5ull,
76 0x6558218568AB9702ull, 0x2AEF7DAD5B6E2F84ull, 0x1521B62829076170ull,
77 0xECDD4775619F1510ull, 0x13CCA830EB61BD96ull, 0x0334FE1EAA0363CFull,
78 0xB5735C904C70A239ull, 0xD59E9E0BCBAADE14ull, 0xEECC86BC60622CA7ull});
79
80 std::vector<uint64_t> output(12);
81
82 {
83 absl::BitGenRef view(urbg);
84 for (auto& v : output) {
85 v = view();
86 }
87 }
88
89 std::vector<uint64_t> expected(
90 {0x0003eb76f6f7f755ull, 0xFFCEA50FDB2F953Bull, 0xC332DDEFBE6C5AA5ull,
91 0x6558218568AB9702ull, 0x2AEF7DAD5B6E2F84ull, 0x1521B62829076170ull,
92 0xECDD4775619F1510ull, 0x13CCA830EB61BD96ull, 0x0334FE1EAA0363CFull,
93 0xB5735C904C70A239ull, 0xD59E9E0BCBAADE14ull, 0xEECC86BC60622CA7ull});
94
95 EXPECT_THAT(output, testing::Eq(expected));
96 }
97
TEST(BitGenRefTest,MockingBitGenBaseOverrides)98 TEST(BitGenRefTest, MockingBitGenBaseOverrides) {
99 ConstBitGen const_gen;
100 EXPECT_EQ(FnTest(const_gen), 42);
101
102 absl::BitGenRef gen_ref(const_gen);
103 EXPECT_EQ(FnTest(gen_ref), 42); // Copy
104 }
105 } // namespace
106 ABSL_NAMESPACE_END
107 } // namespace absl
108