| //===----------------------------------------------------------------------===// |
| // |
| // 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 |
| // UNSUPPORTED: libcpp-no-concepts |
| |
| // constexpr counted_iterator& operator++(); |
| // decltype(auto) operator++(int); |
| // constexpr counted_iterator operator++(int) |
| // requires forward_iterator<I>; |
| |
| #include <iterator> |
| |
| #include "test_macros.h" |
| #include "test_iterators.h" |
| |
| #ifndef TEST_HAS_NO_EXCEPTIONS |
| template <class It> |
| class ThrowsOnInc |
| { |
| It it_; |
| |
| public: |
| typedef std::input_iterator_tag iterator_category; |
| typedef typename std::iterator_traits<It>::value_type value_type; |
| typedef typename std::iterator_traits<It>::difference_type difference_type; |
| typedef It pointer; |
| typedef typename std::iterator_traits<It>::reference reference; |
| |
| constexpr It base() const {return it_;} |
| |
| ThrowsOnInc() = default; |
| explicit constexpr ThrowsOnInc(It it) : it_(it) {} |
| |
| constexpr reference operator*() const {return *it_;} |
| |
| constexpr ThrowsOnInc& operator++() {throw 42;} |
| constexpr ThrowsOnInc operator++(int) {throw 42;} |
| }; |
| #endif // TEST_HAS_NO_EXCEPTIONS |
| |
| struct InputOrOutputArchetype { |
| using difference_type = int; |
| |
| int *ptr; |
| |
| constexpr int operator*() const { return *ptr; } |
| constexpr void operator++(int) { ++ptr; } |
| constexpr InputOrOutputArchetype& operator++() { ++ptr; return *this; } |
| }; |
| |
| template<class Iter> |
| concept PlusEnabled = requires(Iter& iter) { |
| iter++; |
| ++iter; |
| }; |
| |
| constexpr bool test() { |
| int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8}; |
| |
| { |
| using Counted = std::counted_iterator<forward_iterator<int*>>; |
| std::counted_iterator iter(forward_iterator<int*>{buffer}, 8); |
| |
| assert(iter++ == Counted(forward_iterator<int*>{buffer}, 8)); |
| assert(++iter == Counted(forward_iterator<int*>{buffer + 2}, 6)); |
| |
| ASSERT_SAME_TYPE(decltype(iter++), Counted); |
| ASSERT_SAME_TYPE(decltype(++iter), Counted&); |
| } |
| { |
| using Counted = std::counted_iterator<random_access_iterator<int*>>; |
| std::counted_iterator iter(random_access_iterator<int*>{buffer}, 8); |
| |
| assert(iter++ == Counted(random_access_iterator<int*>{buffer}, 8)); |
| assert(++iter == Counted(random_access_iterator<int*>{buffer + 2}, 6)); |
| |
| ASSERT_SAME_TYPE(decltype(iter++), Counted); |
| ASSERT_SAME_TYPE(decltype(++iter), Counted&); |
| } |
| |
| { |
| static_assert( PlusEnabled< std::counted_iterator<random_access_iterator<int*>>>); |
| static_assert(!PlusEnabled<const std::counted_iterator<random_access_iterator<int*>>>); |
| } |
| |
| return true; |
| } |
| |
| int main(int, char**) { |
| test(); |
| static_assert(test()); |
| |
| int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8}; |
| |
| { |
| using Counted = std::counted_iterator<InputOrOutputArchetype>; |
| std::counted_iterator iter(InputOrOutputArchetype{buffer}, 8); |
| |
| iter++; |
| assert((++iter).base().ptr == buffer + 2); |
| |
| ASSERT_SAME_TYPE(decltype(iter++), void); |
| ASSERT_SAME_TYPE(decltype(++iter), Counted&); |
| } |
| { |
| using Counted = std::counted_iterator<cpp20_input_iterator<int*>>; |
| std::counted_iterator iter(cpp20_input_iterator<int*>{buffer}, 8); |
| |
| iter++; |
| assert(++iter == Counted(cpp20_input_iterator<int*>{buffer + 2}, 6)); |
| |
| ASSERT_SAME_TYPE(decltype(iter++), void); |
| ASSERT_SAME_TYPE(decltype(++iter), Counted&); |
| } |
| #ifndef TEST_HAS_NO_EXCEPTIONS |
| { |
| using Counted = std::counted_iterator<ThrowsOnInc<int*>>; |
| std::counted_iterator iter(ThrowsOnInc<int*>{buffer}, 8); |
| try { |
| (void)iter++; |
| assert(false); |
| } catch (int x) { |
| assert(x == 42); |
| assert(iter.count() == 8); |
| } |
| |
| ASSERT_SAME_TYPE(decltype(iter++), ThrowsOnInc<int*>); |
| ASSERT_SAME_TYPE(decltype(++iter), Counted&); |
| } |
| #endif // TEST_HAS_NO_EXCEPTIONS |
| |
| return 0; |
| } |