1/*
2 * Copyright 2014-present Facebook, Inc.
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 <array>
18#include <iostream>
19#include <memory>
20#include <vector>
21
22#include <glog/logging.h>
23
24#include <folly/gen/Base.h>
25#include <folly/gen/Parallel.h>
26#include <folly/portability/GTest.h>
27
28using namespace folly;
29using namespace folly::gen;
30using std::vector;
31
32const auto square = [](int i) { return i * i; };
33const auto even = [](int i) { return 0 == i % 2; };
34static auto sleepyWork = [](int i) {
35 const auto sleepyTime = std::chrono::microseconds(100);
36 std::this_thread::sleep_for(sleepyTime);
37 return i;
38};
39
40static auto isPrime = [](int n) {
41 if (n < 2) {
42 return false;
43 } else if (n > 2) {
44 for (int d = 3; d * d <= n; d += 2) {
45 if (0 == n % d) {
46 return false;
47 }
48 }
49 }
50 return true;
51};
52
53struct {
54 template <class T>
55 std::unique_ptr<T> operator()(T t) const {
56 return std::make_unique<T>(std::move(t));
57 }
58} makeUnique;
59
60static auto primes = seq(1, 1 << 14) | filter(isPrime) | as<vector<size_t>>();
61
62static auto primeFactors = [](int n) {
63 return from(primes) | filter([&](int d) { return 0 == n % d; }) | count;
64};
65
66TEST(ParallelTest, Serial) {
67 EXPECT_EQ(
68 seq(1, 10) | map(square) | filter(even) | sum,
69 seq(1, 10) | parallel(map(square) | filter(even)) | sum);
70}
71
72auto heavyWork = map(primeFactors);
73
74TEST(ParallelTest, ComputeBound64) {
75 int length = 1 << 10;
76 EXPECT_EQ(
77 seq<size_t>(1, length) | heavyWork | sum,
78 seq<size_t>(1, length) | parallel(heavyWork) | sum);
79}
80
81TEST(ParallelTest, Take) {
82 int length = 1 << 18;
83 int limit = 1 << 14;
84 EXPECT_EQ(
85 seq(1, length) | take(limit) | count,
86 seq(1, length) | parallel(heavyWork) | take(limit) | count);
87}
88
89TEST(ParallelTest, Unique) {
90 auto uniqued = from(primes) | map(makeUnique) | as<vector>();
91 EXPECT_EQ(
92 primes.size(),
93 from(primes) | parallel(map(makeUnique)) |
94 parallel(dereference | map(makeUnique)) | dereference | count);
95 EXPECT_EQ(
96 2,
97 from(primes) | parallel(map(makeUnique)) |
98 parallel(dereference | map(makeUnique)) | dereference | take(2) |
99 count);
100}
101
102TEST(ParallelTest, PSum) {
103 EXPECT_EQ(
104 from(primes) | map(sleepyWork) | sum,
105 from(primes) | parallel(map(sleepyWork) | sub(sum)) | sum);
106}
107
108int main(int argc, char* argv[]) {
109 testing::InitGoogleTest(&argc, argv);
110 gflags::ParseCommandLineFlags(&argc, &argv, true);
111 return RUN_ALL_TESTS();
112}
113