| //===----------------------------------------------------------------------===// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| |
| // UNSUPPORTED: c++03, c++11, c++14, c++17 |
| |
| // <algorithm> |
| |
| // template<input_iterator I, sentinel_for<I> S, weakly_incrementable O, |
| // copy_constructible F, class Proj = identity> |
| // requires indirectly_writable<O, indirect_result_t<F&, projected<I, Proj>>> |
| // constexpr ranges::unary_transform_result<I, O> |
| // ranges::transform(I first1, S last1, O result, F op, Proj proj = {}); |
| // template<input_range R, weakly_incrementable O, copy_constructible F, |
| // class Proj = identity> |
| // requires indirectly_writable<O, indirect_result_t<F&, projected<iterator_t<R>, Proj>>> |
| // constexpr ranges::unary_transform_result<borrowed_iterator_t<R>, O> |
| // ranges::transform(R&& r, O result, F op, Proj proj = {}); |
| |
| #include <algorithm> |
| #include <array> |
| #include <cassert> |
| #include <functional> |
| #include <ranges> |
| |
| #include "test_iterators.h" |
| #include "almost_satisfies_types.h" |
| |
| template <class Range> |
| concept HasTranformR = requires(Range r, int* out) { std::ranges::transform(r, out, std::identity{}); }; |
| |
| static_assert(HasTranformR<std::array<int, 1>>); |
| static_assert(!HasTranformR<int>); |
| static_assert(!HasTranformR<InputRangeNotDerivedFrom>); |
| static_assert(!HasTranformR<InputRangeNotIndirectlyReadable>); |
| static_assert(!HasTranformR<InputRangeNotInputOrOutputIterator>); |
| static_assert(!HasTranformR<InputRangeNotSentinelSemiregular>); |
| static_assert(!HasTranformR<InputRangeNotSentinelEqualityComparableWith>); |
| |
| template <class It, class Sent = It> |
| concept HasTransformIt = |
| requires(It it, Sent sent, int* out) { std::ranges::transform(it, sent, out, std::identity{}); }; |
| |
| static_assert(HasTransformIt<int*>); |
| static_assert(!HasTransformIt<InputIteratorNotDerivedFrom>); |
| static_assert(!HasTransformIt<InputIteratorNotIndirectlyReadable>); |
| static_assert(!HasTransformIt<InputIteratorNotInputOrOutputIterator>); |
| static_assert(!HasTransformIt<cpp20_input_iterator<int*>, SentinelForNotSemiregular>); |
| static_assert(!HasTransformIt<cpp20_input_iterator<int*>, InputRangeNotSentinelEqualityComparableWith>); |
| |
| template <class It> |
| concept HasTransformOut = requires(int* it, int* sent, It out, std::array<int, 2> range) { |
| std::ranges::transform(it, sent, out, std::identity{}); |
| std::ranges::transform(range, out, std::identity{}); |
| }; |
| static_assert(HasTransformOut<int*>); |
| static_assert(!HasTransformOut<WeaklyIncrementableNotMovable>); |
| |
| // check indirectly_readable |
| static_assert(HasTransformOut<char*>); |
| static_assert(!HasTransformOut<int**>); |
| |
| struct MoveOnlyFunctor { |
| MoveOnlyFunctor(const MoveOnlyFunctor&) = delete; |
| MoveOnlyFunctor(MoveOnlyFunctor&&) = default; |
| int operator()(int); |
| }; |
| |
| template <class Func> |
| concept HasTransformFuncUnary = requires(int* it, int* sent, int* out, std::array<int, 2> range, Func func) { |
| std::ranges::transform(it, sent, out, func); |
| std::ranges::transform(range, out, func); |
| }; |
| static_assert(HasTransformFuncUnary<std::identity>); |
| static_assert(!HasTransformFuncUnary<MoveOnlyFunctor>); |
| |
| static_assert(std::is_same_v<std::ranges::unary_transform_result<int, long>, std::ranges::in_out_result<int, long>>); |
| |
| // clang-format off |
| template <class In1, class Out, class Sent1> |
| constexpr bool test_iterators() { |
| { // simple |
| { |
| int a[] = {1, 2, 3, 4, 5}; |
| int b[5]; |
| std::same_as<std::ranges::in_out_result<In1, Out>> decltype(auto) ret = |
| std::ranges::transform(In1(a), Sent1(In1(a + 5)), Out(b), [](int i) { return i * 2; }); |
| assert((std::to_array(b) == std::array{2, 4, 6, 8, 10})); |
| assert(base(ret.in) == a + 5); |
| assert(base(ret.out) == b + 5); |
| } |
| |
| { |
| int a[] = {1, 2, 3, 4, 5}; |
| int b[5]; |
| auto range = std::ranges::subrange(In1(a), Sent1(In1(a + 5))); |
| std::same_as<std::ranges::in_out_result<In1, Out>> decltype(auto) ret = |
| std::ranges::transform(range, Out(b), [](int i) { return i * 2; }); |
| assert((std::to_array(b) == std::array{2, 4, 6, 8, 10})); |
| assert(base(ret.in) == a + 5); |
| assert(base(ret.out) == b + 5); |
| } |
| } |
| |
| { // first range empty |
| { |
| int a[] = {}; |
| int b[5]; |
| auto ret = std::ranges::transform(In1(a), Sent1(In1(a)), Out(b), [](int i) { return i * 2; }); |
| assert(base(ret.in) == a); |
| assert(base(ret.out) == b); |
| } |
| |
| { |
| int a[] = {}; |
| int b[5]; |
| auto range = std::ranges::subrange(In1(a), Sent1(In1(a))); |
| auto ret = std::ranges::transform(range, Out(b), [](int i) { return i * 2; }); |
| assert(base(ret.in) == a); |
| assert(base(ret.out) == b); |
| } |
| } |
| |
| { // one element range |
| { |
| int a[] = {2}; |
| int b[5]; |
| auto ret = std::ranges::transform(In1(a), Sent1(In1(a + 1)), Out(b), [](int i) { return i * 2; }); |
| assert(b[0] == 4); |
| assert(base(ret.in) == a + 1); |
| assert(base(ret.out) == b + 1); |
| } |
| |
| { |
| int a[] = {2}; |
| int b[5]; |
| auto range = std::ranges::subrange(In1(a), Sent1(In1(a + 1))); |
| auto ret = std::ranges::transform(range, Out(b), [](int i) { return i * 2; }); |
| assert(b[0] == 4); |
| assert(base(ret.in) == a + 1); |
| assert(base(ret.out) == b + 1); |
| } |
| } |
| |
| { // check that the transform function and projection call counts are correct |
| { |
| int predCount = 0; |
| int projCount = 0; |
| auto pred = [&](int) { ++predCount; return 1; }; |
| auto proj = [&](int) { ++projCount; return 0; }; |
| int a[] = {1, 2, 3, 4}; |
| std::array<int, 4> c; |
| std::ranges::transform(In1(a), Sent1(In1(a + 4)), Out(c.data()), pred, proj); |
| assert(predCount == 4); |
| assert(projCount == 4); |
| assert((c == std::array{1, 1, 1, 1})); |
| } |
| { |
| int predCount = 0; |
| int projCount = 0; |
| auto pred = [&](int) { ++predCount; return 1; }; |
| auto proj = [&](int) { ++projCount; return 0; }; |
| int a[] = {1, 2, 3, 4}; |
| std::array<int, 4> c; |
| auto range = std::ranges::subrange(In1(a), Sent1(In1(a + 4))); |
| std::ranges::transform(range, Out(c.data()), pred, proj); |
| assert(predCount == 4); |
| assert(projCount == 4); |
| assert((c == std::array{1, 1, 1, 1})); |
| } |
| } |
| return true; |
| } |
| // clang-format on |
| |
| template <class Out> |
| constexpr void test_iterator_in1() { |
| test_iterators<cpp17_input_iterator<int*>, Out, sentinel_wrapper<cpp17_input_iterator<int*>>>(); |
| test_iterators<cpp20_input_iterator<int*>, Out, sentinel_wrapper<cpp20_input_iterator<int*>>>(); |
| test_iterators<forward_iterator<int*>, Out, forward_iterator<int*>>(); |
| test_iterators<bidirectional_iterator<int*>, Out, bidirectional_iterator<int*>>(); |
| test_iterators<random_access_iterator<int*>, Out, random_access_iterator<int*>>(); |
| test_iterators<contiguous_iterator<int*>, Out, contiguous_iterator<int*>>(); |
| test_iterators<int*, Out, int*>(); |
| // static_asserting here to avoid hitting the constant evaluation step limit |
| static_assert(test_iterators<cpp17_input_iterator<int*>, Out, sentinel_wrapper<cpp17_input_iterator<int*>>>()); |
| static_assert(test_iterators<cpp20_input_iterator<int*>, Out, sentinel_wrapper<cpp20_input_iterator<int*>>>()); |
| static_assert(test_iterators<forward_iterator<int*>, Out, forward_iterator<int*>>()); |
| static_assert(test_iterators<bidirectional_iterator<int*>, Out, bidirectional_iterator<int*>>()); |
| static_assert(test_iterators<random_access_iterator<int*>, Out, random_access_iterator<int*>>()); |
| static_assert(test_iterators<contiguous_iterator<int*>, Out, contiguous_iterator<int*>>()); |
| static_assert(test_iterators<int*, Out, int*>()); |
| } |
| |
| constexpr bool test() { |
| { // check that std::ranges::dangling is returned properly |
| std::array<int, 5> b; |
| std::same_as<std::ranges::in_out_result<std::ranges::dangling, int*>> auto ret = |
| std::ranges::transform(std::array{1, 2, 3, 5, 4}, b.data(), [](int i) { return i * i; }); |
| assert((b == std::array{1, 4, 9, 25, 16})); |
| assert(ret.out == b.data() + b.size()); |
| } |
| |
| { // check that returning another type from the projection works |
| { |
| struct S { int i; int other; }; |
| S a[] = { S{0, 0}, S{1, 0}, S{3, 0}, S{10, 0} }; |
| std::array<int, 4> b; |
| std::ranges::transform(a, a + 4, b.begin(), [](S s) { return s.i; }); |
| assert((b == std::array{0, 1, 3, 10})); |
| } |
| { |
| struct S { int i; int other; }; |
| S a[] = { S{0, 0}, S{1, 0}, S{3, 0}, S{10, 0} }; |
| std::array<int, 4> b; |
| std::ranges::transform(a, b.begin(), [](S s) { return s.i; }); |
| assert((b == std::array{0, 1, 3, 10})); |
| } |
| } |
| |
| { // check that std::invoke is used |
| struct S { int i; }; |
| S a[] = { S{1}, S{3}, S{2} }; |
| std::array<int, 3> b; |
| auto ret = std::ranges::transform(a, b.data(), [](int i) { return i; }, &S::i); |
| assert((b == std::array{1, 3, 2})); |
| assert(ret.out == b.data() + 3); |
| } |
| |
| return true; |
| } |
| |
| int main(int, char**) { |
| test_iterator_in1<cpp17_output_iterator<int*>>(); |
| test_iterator_in1<cpp20_output_iterator<int*>>(); |
| test_iterator_in1<forward_iterator<int*>>(); |
| test_iterator_in1<bidirectional_iterator<int*>>(); |
| test_iterator_in1<random_access_iterator<int*>>(); |
| test_iterator_in1<contiguous_iterator<int*>>(); |
| test_iterator_in1<int*>(); |
| test(); |
| static_assert(test()); |
| |
| return 0; |
| } |