| //===----------------------------------------------------------------------===// |
| // |
| // 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 |
| |
| // <memory> |
| // |
| // template<input_iterator I, nothrow-forward-iterator O, nothrow-sentinel-for<O> S> |
| // requires constructible_from<iter_value_t<O>, iter_reference_t<I>> |
| // uninitialized_copy_n_result<I, O> uninitialized_copy_n(I ifirst, iter_difference_t<I> n, O ofirst, S olast); // since C++20 |
| |
| #include <algorithm> |
| #include <cassert> |
| #include <iterator> |
| #include <memory> |
| #include <ranges> |
| #include <type_traits> |
| #include <utility> |
| |
| #include "../buffer.h" |
| #include "../counted.h" |
| #include "test_macros.h" |
| #include "test_iterators.h" |
| |
| // TODO(varconst): consolidate the ADL checks into a single file. |
| // Because this is a variable and not a function, it's guaranteed that ADL won't be used. However, |
| // implementations are allowed to use a different mechanism to achieve this effect, so this check is |
| // libc++-specific. |
| LIBCPP_STATIC_ASSERT(std::is_class_v<decltype(std::ranges::uninitialized_copy_n)>); |
| |
| static_assert(std::is_invocable_v<decltype(std::ranges::uninitialized_copy_n), int*, std::size_t, long*, long*>); |
| struct NotConvertibleFromInt {}; |
| static_assert(!std::is_invocable_v<decltype(std::ranges::uninitialized_copy_n), int*, std::size_t, NotConvertibleFromInt*, |
| NotConvertibleFromInt*>); |
| |
| int main(int, char**) { |
| // An empty range -- no default constructors should be invoked. |
| { |
| Counted in[] = {Counted()}; |
| Buffer<Counted, 1> out; |
| Counted::reset(); |
| |
| auto result = std::ranges::uninitialized_copy_n(in, 0, out.begin(), out.end()); |
| assert(Counted::current_objects == 0); |
| assert(Counted::total_objects == 0); |
| assert(Counted::total_copies == 0); |
| assert(result.in == in); |
| assert(result.out == out.begin()); |
| } |
| Counted::reset(); |
| |
| // A range containing several objects. |
| { |
| constexpr int N = 5; |
| Counted in[N] = {Counted(1), Counted(2), Counted(3), Counted(4), Counted(5)}; |
| Buffer<Counted, N> out; |
| Counted::reset(); |
| |
| auto result = std::ranges::uninitialized_copy_n(in, N, out.begin(), out.end()); |
| ASSERT_SAME_TYPE(decltype(result), std::ranges::uninitialized_copy_n_result<Counted*, Counted*>); |
| |
| assert(Counted::current_objects == N); |
| assert(Counted::total_objects == N); |
| assert(Counted::total_copies == N); |
| assert(Counted::total_moves == 0); |
| assert(std::equal(in, in + N, out.begin(), out.end())); |
| assert(result.in == in + N); |
| assert(result.out == out.end()); |
| |
| std::destroy(out.begin(), out.end()); |
| } |
| Counted::reset(); |
| |
| // An exception is thrown while objects are being created -- the existing objects should stay |
| // valid. (iterator, sentinel) overload. |
| #ifndef TEST_HAS_NO_EXCEPTIONS |
| { |
| constexpr int M = 3; |
| constexpr int N = 5; |
| Counted in[N] = {Counted(1), Counted(2), Counted(3), Counted(4), Counted(5)}; |
| Counted out[N] = {Counted(6), Counted(7), Counted(8), Counted(9), Counted(10)}; |
| Counted::reset(); |
| |
| Counted::throw_on = M; // When constructing out[3]. |
| try { |
| std::ranges::uninitialized_copy_n(in, N, out, out + N); |
| assert(false); |
| } catch (...) { |
| } |
| assert(Counted::current_objects == 0); |
| assert(Counted::total_objects == M); |
| assert(Counted::total_copies == M); |
| assert(Counted::total_moves == 0); |
| |
| assert(out[4].value == 10); |
| } |
| Counted::reset(); |
| |
| #endif // TEST_HAS_NO_EXCEPTIONS |
| |
| // Works with const iterators. |
| { |
| constexpr int N = 5; |
| Counted in[N] = {Counted(1), Counted(2), Counted(3), Counted(4), Counted(5)}; |
| Buffer<Counted, N> out; |
| Counted::reset(); |
| |
| std::ranges::uninitialized_copy_n(in, N, out.cbegin(), out.cend()); |
| assert(Counted::current_objects == N); |
| assert(Counted::total_objects == N); |
| assert(std::equal(in, in + N, out.begin(), out.end())); |
| |
| std::destroy(out.begin(), out.end()); |
| } |
| Counted::reset(); |
| |
| // Conversions. |
| { |
| constexpr int N = 3; |
| int in[N] = {1, 2, 3}; |
| Buffer<double, N> out; |
| |
| std::ranges::uninitialized_copy_n(in, N, out.begin(), out.end()); |
| assert(std::equal(in, in + N, out.begin(), out.end())); |
| } |
| |
| // Destination range is shorter than the source range. |
| { |
| constexpr int M = 3; |
| constexpr int N = 5; |
| Counted in[N] = {Counted(1), Counted(2), Counted(3), Counted(4), Counted(5)}; |
| Buffer<Counted, M> out; |
| Counted::reset(); |
| |
| auto result = std::ranges::uninitialized_copy_n(in, N, out.begin(), out.end()); |
| assert(Counted::current_objects == M); |
| assert(Counted::total_objects == M); |
| assert(Counted::total_copies == M); |
| assert(Counted::total_moves == 0); |
| |
| assert(std::equal(in, in + M, out.begin(), out.end())); |
| assert(result.in == in + M); |
| assert(result.out == out.end()); |
| } |
| |
| // Move-only iterators are supported. |
| { |
| using MoveOnlyIter = cpp20_input_iterator<const int*>; |
| static_assert(!std::is_copy_constructible_v<MoveOnlyIter>); |
| |
| constexpr int N = 3; |
| int buffer[N] = {1, 2, 3}; |
| |
| MoveOnlyIter in(buffer); |
| Buffer<int, N> out; |
| std::ranges::uninitialized_copy_n(std::move(in), N, out.begin(), out.end()); |
| } |
| |
| return 0; |
| } |