1 /*
2 * Copyright 2020 Google LLC
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 * http://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
17 #include "fcp/base/process_unique_id.h"
18
19 #include <thread> // NOLINT(build/c++11)
20
21 #include "gtest/gtest.h"
22 #include "absl/container/flat_hash_set.h"
23
24 namespace fcp {
25
TEST(UniqueIdGeneratorTest,CallingNextYieldsDifferentIds)26 TEST(UniqueIdGeneratorTest, CallingNextYieldsDifferentIds) {
27 uint64_t id1 = ProcessUniqueId::Next().value();
28 uint64_t id2 = ProcessUniqueId::Next().value();
29 EXPECT_NE(id1, id2);
30 }
31
TEST(UniqueIdGeneratorTest,MultipleThreads)32 TEST(UniqueIdGeneratorTest, MultipleThreads) {
33 const int n = 15;
34 std::thread threads[n];
35 uint64_t ids[n];
36 for (int i = 0; i < n; i++) {
37 threads[i] =
38 std::thread([&ids, i]() { ids[i] = ProcessUniqueId::Next().value(); });
39 }
40 for (int i = 0; i < n; i++) {
41 threads[i].join();
42 }
43 absl::flat_hash_set<uint64_t> id_set;
44 for (int i = 0; i < n; i++) {
45 bool inserted = id_set.insert(ids[i]).second;
46 EXPECT_TRUE(inserted);
47 }
48 }
49
50 } // namespace fcp
51