1 /*
2 * Copyright (c) Facebook, Inc. and its affiliates.
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 <memory>
18 #include <mutex>
19
20 #include <folly/futures/Future.h>
21 #include <folly/portability/GTest.h>
22
23 using namespace folly;
24
TEST(When,predicateFalse)25 TEST(When, predicateFalse) {
26 int i = 0;
27 auto thunk = [&] { return makeFuture().thenValue([&](auto&&) { i += 1; }); };
28
29 // false
30 auto f1 = folly::when(false, thunk);
31 f1.wait();
32 EXPECT_EQ(0, i);
33
34 auto sfThunk = [&] {
35 return makeSemiFuture().deferValue([&](auto&&) { i += 1; });
36 };
37
38 // false
39 auto f1s = folly::when(false, sfThunk);
40 f1s.wait();
41 EXPECT_EQ(0, i);
42 }
43
TEST(When,predicateTrue)44 TEST(When, predicateTrue) {
45 int i = 0;
46 auto thunk = [&] { return makeFuture().thenValue([&](auto&&) { i += 1; }); };
47
48 // true
49 auto f2 = folly::when(true, thunk);
50 f2.wait();
51 EXPECT_EQ(1, i);
52
53 auto sfThunk = [&] {
54 return makeSemiFuture().deferValue([&](auto&&) { i += 1; });
55 };
56
57 // true
58 auto f2s = folly::when(true, sfThunk);
59 f2s.wait();
60 EXPECT_EQ(2, i);
61 }
62