/*
* Copyright (c) Meta Platforms, Inc. and affiliates.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <folly/futures/Future.h>
#include <folly/portability/GTest.h>
using namespace folly;
TEST(Reduce, basic) {
auto makeFutures = [](int count) {
std::vector<Future<int>> fs;
for (int i = 1; i <= count; ++i) {
fs.emplace_back(makeFuture(i));
}
return fs;
};
// Empty (Try)
{
auto fs = makeFutures(0);
Future<double> f1 =
reduce(fs, 1.2, [](double a, Try<int>&& b) { return a + *b + 0.1; });
EXPECT_EQ(1.2, std::move(f1).get());
}
// One (Try)
{
auto fs = makeFutures(1);
Future<double> f1 =
reduce(fs, 0.0, [](double a, Try<int>&& b) { return a + *b + 0.1; });
EXPECT_EQ(1.1, std::move(f1).get());
}
// Returning values (Try)
{
auto fs = makeFutures(3);
Future<double> f1 =
reduce(fs, 0.0, [](double a, Try<int>&& b) { return a + *b + 0.1; });
EXPECT_EQ(6.3, std::move(f1).get());
}
// Returning values
{
auto fs = makeFutures(3);
Future<double> f1 =
reduce(fs, 0.0, [](double a, int&& b) { return a + b + 0.1; });
EXPECT_EQ(6.3, std::move(f1).get());
}
// Returning futures (Try)
{
auto fs = makeFutures(3);
Future<double> f2 = reduce(fs, 0.0, [](double a, Try<int>&& b) {
return makeFuture<double>(a + *b + 0.1);
});
EXPECT_EQ(6.3, std::move(f2).get());
}
// Returning futures
{
auto fs = makeFutures(3);
Future<double> f2 = reduce(fs, 0.0, [](double a, int&& b) {
return makeFuture<double>(a + b + 0.1);
});
EXPECT_EQ(6.3, std::move(f2).get());
}
}
TEST(Reduce, chain) {
auto makeFutures = [](int count) {
std::vector<Future<int>> fs;
for (int i = 1; i <= count; ++i) {
fs.emplace_back(makeFuture(i));
}
return fs;
};
{
auto f = collectAll(makeFutures(3))
.toUnsafeFuture()
.reduce(0, [](int a, Try<int>&& b) { return a + *b; });
EXPECT_EQ(6, std::move(f).get());
}
{
auto f =
collect(makeFutures(3)).toUnsafeFuture().reduce(0, [](int a, int&& b) {
return a + b;
});
EXPECT_EQ(6, std::move(f).get());
}
}
TEST(Reduce, unorderedReduce) {
{
std::vector<Future<int>> fs;
fs.push_back(makeFuture(1));
fs.push_back(makeFuture(2));
fs.push_back(makeFuture(3));
Future<double> f =
unorderedReduce(fs.begin(), fs.end(), 0.0, [](double /* a */, int&& b) {
return double(b);
});
EXPECT_EQ(3.0, std::move(f).get());
}
{
Promise<int> p1;
Promise<int> p2;
Promise<int> p3;
std::vector<Future<int>> fs;
fs.push_back(p1.getFuture());
fs.push_back(p2.getFuture());
fs.push_back(p3.getFuture());
Future<double> f =
unorderedReduce(fs.begin(), fs.end(), 0.0, [](double /* a */, int&& b) {
return double(b);
});
p3.setValue(3);
p2.setValue(2);
p1.setValue(1);
EXPECT_EQ(1.0, std::move(f).get());
}
{
Promise<int> p1;
Promise<int> p2;
Promise<int> p3;
std::vector<SemiFuture<int>> fs;
fs.push_back(p1.getSemiFuture());
fs.push_back(p2.getSemiFuture());
fs.push_back(p3.getSemiFuture());
SemiFuture<double> f = unorderedReduceSemiFuture(
fs.begin(), fs.end(), 0.0, [](double /* a */, int&& b) {
return double(b);
});
p3.setValue(3);
p2.setValue(2);
p1.setValue(1);
EXPECT_EQ(1.0, std::move(f).get());
}
}
TEST(Reduce, unorderedReduceException) {
{
Promise<int> p1;
Promise<int> p2;
Promise<int> p3;
std::vector<Future<int>> fs;
fs.push_back(p1.getFuture());
fs.push_back(p2.getFuture());
fs.push_back(p3.getFuture());
Future<double> f =
unorderedReduce(fs.begin(), fs.end(), 0.0, [](double /* a */, int&& b) {
return b + 0.0;
});
p3.setValue(3);
p2.setException(exception_wrapper(std::runtime_error("blah")));
p1.setValue(1);
EXPECT_THROW(std::move(f).get(), std::runtime_error);
}
{
Promise<int> p1;
Promise<int> p2;
Promise<int> p3;
std::vector<SemiFuture<int>> fs;
fs.push_back(p1.getSemiFuture());
fs.push_back(p2.getSemiFuture());
fs.push_back(p3.getSemiFuture());
SemiFuture<double> f = unorderedReduceSemiFuture(
fs.begin(), fs.end(), 0.0, [](double /* a */, int&& b) {
return b + 0.0;
});
p3.setValue(3);
p2.setException(exception_wrapper(std::runtime_error("blah")));
p1.setValue(1);
EXPECT_THROW(std::move(f).get(), std::runtime_error);
}
}
TEST(Reduce, unorderedReduceFuture) {
Promise<int> p1;
Promise<int> p2;
Promise<int> p3;
std::vector<Future<int>> fs;
fs.push_back(p1.getFuture());
fs.push_back(p2.getFuture());
fs.push_back(p3.getFuture());
std::vector<Promise<double>> ps(3);
Future<int> f =
unorderedReduce(fs.begin(), fs.end(), 0.0, [&](double /* a */, int&& b) {
return ps[b - 1].getFuture();
});
p3.setValue(3);
p2.setValue(2);
p1.setValue(1);
ps[0].setValue(1.0);
ps[1].setValue(2.0);
ps[2].setValue(3.0);
EXPECT_EQ(1.0, std::move(f).get());
}