1/*
2 * Copyright 2015-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 <folly/futures/Future.h>
18#include <folly/portability/GTest.h>
19
20using namespace folly;
21
22// A simple scenario for the unwrap call, when the promise was fulfilled
23// before calling to unwrap.
24TEST(Unwrap, simpleScenario) {
25 Future<int> encapsulated_future = makeFuture(5484);
26 Future<Future<int>> future = makeFuture(std::move(encapsulated_future));
27 EXPECT_EQ(5484, std::move(future).unwrap().value());
28}
29
30// Makes sure that unwrap() works when chaning Future's commands.
31TEST(Unwrap, chainCommands) {
32 Future<Future<int>> future = makeFuture(makeFuture(5484));
33 auto unwrapped =
34 std::move(future).unwrap().thenValue([](int i) { return i; });
35 EXPECT_EQ(5484, unwrapped.value());
36}
37
38// Makes sure that the unwrap call also works when the promise was not yet
39// fulfilled, and that the returned Future<T> becomes ready once the promise
40// is fulfilled.
41TEST(Unwrap, futureNotReady) {
42 Promise<Future<int>> p;
43 Future<Future<int>> future = p.getFuture();
44 Future<int> unwrapped = std::move(future).unwrap();
45 // Sanity - should not be ready before the promise is fulfilled.
46 ASSERT_FALSE(unwrapped.isReady());
47 // Fulfill the promise and make sure the unwrapped future is now ready.
48 p.setValue(makeFuture(5484));
49 ASSERT_TRUE(unwrapped.isReady());
50 EXPECT_EQ(5484, unwrapped.value());
51}
52