blob: 8c19488bbb60a8bd908f445e60e719059d311033 [file] [log] [blame]
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// <numeric>
// UNSUPPORTED: c++03, c++11, c++14
// UNSUPPORTED: clang-8
// UNSUPPORTED: gcc-9
// Became constexpr in C++20
// template <class InputIterator1, class T,
// class BinaryOperation, class UnaryOperation>
// T transform_reduce(InputIterator1 first1, InputIterator1 last1,
// T init, BinaryOperation binary_op, UnaryOperation unary_op);
//
#include <numeric>
#include <cassert>
#include <utility>
#include <iterator>
#include "test_macros.h"
#include "MoveOnly.h"
#include "test_iterators.h"
struct identity
{
template <class T>
constexpr decltype(auto) operator()(T&& x) const {
return std::forward<T>(x);
}
};
struct twice
{
template <class T>
constexpr auto operator()(const T& x) const {
return 2 * x;
}
};
template <class Iter1, class T, class BOp, class UOp>
TEST_CONSTEXPR_CXX20 void
test(Iter1 first1, Iter1 last1, T init, BOp bOp, UOp uOp, T x)
{
static_assert( std::is_same_v<T,
decltype(std::transform_reduce(first1, last1, init, bOp, uOp))> );
assert(std::transform_reduce(first1, last1, init, bOp, uOp) == x);
}
template <class Iter>
TEST_CONSTEXPR_CXX20 void
test()
{
int ia[] = {1, 2, 3, 4, 5, 6};
unsigned sa = sizeof(ia) / sizeof(ia[0]);
test(Iter(ia), Iter(ia), 0, std::plus<>(), identity(), 0);
test(Iter(ia), Iter(ia), 1, std::multiplies<>(), identity(), 1);
test(Iter(ia), Iter(ia+1), 0, std::multiplies<>(), identity(), 0);
test(Iter(ia), Iter(ia+1), 2, std::plus<>(), identity(), 3);
test(Iter(ia), Iter(ia+2), 0, std::plus<>(), identity(), 3);
test(Iter(ia), Iter(ia+2), 3, std::multiplies<>(), identity(), 6);
test(Iter(ia), Iter(ia+sa), 4, std::multiplies<>(), identity(), 2880);
test(Iter(ia), Iter(ia+sa), 4, std::plus<>(), identity(), 25);
test(Iter(ia), Iter(ia), 0, std::plus<>(), twice(), 0);
test(Iter(ia), Iter(ia), 1, std::multiplies<>(), twice(), 1);
test(Iter(ia), Iter(ia+1), 0, std::multiplies<>(), twice(), 0);
test(Iter(ia), Iter(ia+1), 2, std::plus<>(), twice(), 4);
test(Iter(ia), Iter(ia+2), 0, std::plus<>(), twice(), 6);
test(Iter(ia), Iter(ia+2), 3, std::multiplies<>(), twice(), 24);
test(Iter(ia), Iter(ia+sa), 4, std::multiplies<>(), twice(), 184320); // 64 * 2880
test(Iter(ia), Iter(ia+sa), 4, std::plus<>(), twice(), 46);
}
template <typename T, typename Init>
TEST_CONSTEXPR_CXX20 void
test_return_type()
{
T *p = nullptr;
static_assert( std::is_same_v<Init,
decltype(std::transform_reduce(p, p, Init{}, std::plus<>(), identity()))> );
}
TEST_CONSTEXPR_CXX20 void
test_move_only_types()
{
MoveOnly ia[] = {{1}, {2}, {3}};
assert(60 ==
std::transform_reduce(std::begin(ia), std::end(ia), MoveOnly{0},
[](const MoveOnly& lhs, const MoveOnly& rhs) { return MoveOnly{lhs.get() + rhs.get()}; },
[](const MoveOnly& target) { return MoveOnly{target.get() * 10}; }).get());
}
TEST_CONSTEXPR_CXX20 bool
test()
{
test_return_type<char, int>();
test_return_type<int, int>();
test_return_type<int, unsigned long>();
test_return_type<float, int>();
test_return_type<short, float>();
test_return_type<double, char>();
test_return_type<char, double>();
// All the iterator categories
test<input_iterator <const int*> >();
test<forward_iterator <const int*> >();
test<bidirectional_iterator<const int*> >();
test<random_access_iterator<const int*> >();
test<const int*>();
test< int*>();
// Make sure the math is done using the correct type
{
auto v = {1, 2, 3, 4, 5, 6};
unsigned res = std::transform_reduce(v.begin(), v.end(), 1U, std::multiplies<>(), twice());
assert(res == 46080); // 6! * 64 will not fit into a char
}
test_move_only_types();
return true;
}
int main(int, char**)
{
test();
#if TEST_STD_VER > 17
static_assert(test());
#endif
return 0;
}