diff --git a/libcxx/include/__ranges/join_view.h b/libcxx/include/__ranges/join_view.h index 327b349f476a7..364f056d8d2cf 100644 --- a/libcxx/include/__ranges/join_view.h +++ b/libcxx/include/__ranges/join_view.h @@ -410,8 +410,13 @@ struct __segmented_iterator_traits<_JoinViewIterator> { static constexpr _LIBCPP_HIDE_FROM_ABI _JoinViewIterator __compose(__segment_iterator __seg_iter, __local_iterator __local_iter) { - return _JoinViewIterator( - std::move(__seg_iter).__get_data(), std::move(__seg_iter).__get_iter(), std::move(__local_iter)); + auto&& __parent = std::move(__seg_iter).__get_data(); + auto&& __outer = std::move(__seg_iter).__get_iter(); + if (__local_iter == ranges::end(*__outer)) { + ++__outer; + return _JoinViewIterator(*__parent, __outer); + } + return _JoinViewIterator(__parent, __outer, std::move(__local_iter)); } }; diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find/ranges.find.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find/ranges.find.pass.cpp index 5b4abc45b6f4f..3303b4a76f467 100644 --- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find/ranges.find.pass.cpp +++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find/ranges.find.pass.cpp @@ -272,57 +272,100 @@ class Comparable { friend bool operator==(const Comparable& lhs, long long rhs) { return comparable_data[lhs.index_] == rhs; } }; -void test_deque() { - { // empty deque - std::deque data; - assert(std::ranges::find(data, 4) == data.end()); - assert(std::ranges::find(data.begin(), data.end(), 4) == data.end()); - } - - { // single element - match - std::deque data = {4}; - assert(std::ranges::find(data, 4) == data.begin()); - assert(std::ranges::find(data.begin(), data.end(), 4) == data.begin()); - } - - { // single element - no match - std::deque data = {3}; - assert(std::ranges::find(data, 4) == data.end()); - assert(std::ranges::find(data.begin(), data.end(), 4) == data.end()); - } - - // many elements - for (auto size : {2, 3, 1023, 1024, 1025, 2047, 2048, 2049}) { - { // last element match +void test_segmented_iterator_types() { + // Test the optimized find algorithm for types that implement the segment iterator trait + // deque + { + { // empty deque std::deque data; - data.resize(size); - std::fill(data.begin(), data.end(), 3); - data[size - 1] = 4; - assert(std::ranges::find(data, 4) == data.end() - 1); - assert(std::ranges::find(data.begin(), data.end(), 4) == data.end() - 1); + assert(std::ranges::find(data, 4) == data.end()); + assert(std::ranges::find(data.begin(), data.end(), 4) == data.end()); } - { // second-last element match - std::deque data; - data.resize(size); - std::fill(data.begin(), data.end(), 3); - data[size - 2] = 4; - assert(std::ranges::find(data, 4) == data.end() - 2); - assert(std::ranges::find(data.begin(), data.end(), 4) == data.end() - 2); + { // single element - match + std::deque data = {4}; + assert(std::ranges::find(data, 4) == data.begin()); + assert(std::ranges::find(data.begin(), data.end(), 4) == data.begin()); } - { // no match - std::deque data; - data.resize(size); - std::fill(data.begin(), data.end(), 3); + { // single element - no match + std::deque data = {3}; assert(std::ranges::find(data, 4) == data.end()); assert(std::ranges::find(data.begin(), data.end(), 4) == data.end()); } + + // many elements + for (auto size : {2, 3, 1023, 1024, 1025, 2047, 2048, 2049}) { + { // last element match + std::deque data; + data.resize(size); + std::fill(data.begin(), data.end(), 3); + data[size - 1] = 4; + assert(std::ranges::find(data, 4) == data.end() - 1); + assert(std::ranges::find(data.begin(), data.end(), 4) == data.end() - 1); + } + + { // second-last element match + std::deque data; + data.resize(size); + std::fill(data.begin(), data.end(), 3); + data[size - 2] = 4; + assert(std::ranges::find(data, 4) == data.end() - 2); + assert(std::ranges::find(data.begin(), data.end(), 4) == data.end() - 2); + } + + { // no match + std::deque data; + data.resize(size); + std::fill(data.begin(), data.end(), 3); + assert(std::ranges::find(data, 4) == data.end()); + assert(std::ranges::find(data.begin(), data.end(), 4) == data.end()); + } + } + } + // join_view ranges adaptor + { + { // single element - match + int data[1][1] = {{4}}; + auto joined = std::views::join(data); + assert(std::ranges::find(joined, 4) == std::ranges::begin(joined)); + } + { // single element - no match + // (reproducer for https://llvm.org/PR158279, where the iterator would never reach the end sentinel) + int data[1][1] = {{3}}; + auto joined = std::views::join(data); + assert(std::ranges::find(joined, 4) == std::ranges::end(joined)); + } + { // several sub-arrays of size 1 - match + int data[3][1] = {{0}, {4}, {0}}; + auto joined = std::views::join(data); + assert(std::ranges::find(joined, 4) == std::next(std::ranges::begin(joined))); + } + { // several sub-arrays of size 2 - match in second element of an array + int data[3][2] = {{0, 0}, {0, 4}, {0, 0}}; + auto joined = std::views::join(data); + assert(std::ranges::find(joined, 4) == std::ranges::next(std::ranges::begin(joined), 3)); + } + { // vector of empty vectors + std::vector> data = {{}, {}}; + auto joined = std::views::join(data); + assert(std::ranges::find(joined, 4) == std::ranges::end(joined)); + } + { // vector of variably sized vectors - match + std::vector> data = {{}, {}, {3, 4}, {}, {}}; + auto joined = std::views::join(data); + assert(std::ranges::find(joined, 4) == std::ranges::next(std::ranges::begin(joined))); + } + { // vector of variably sized vectors - no match + std::vector> data = {{}, {}, {3, 5}, {}, {}}; + auto joined = std::views::join(data); + assert(std::ranges::find(joined, 4) == std::ranges::end(joined)); + } } } int main(int, char**) { - test_deque(); + test_segmented_iterator_types(); test(); static_assert(test());