| //===----------------------------------------------------------------------===// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| |
| // <algorithm> |
| |
| // UNSUPPORTED: c++03, c++11, c++14, c++17 |
| |
| // template<forward_iterator I, sentinel_for<I> S, class Proj = identity, |
| // indirect_strict_weak_order<projected<I, Proj>> Comp = ranges::less> |
| // constexpr ranges::minmax_element_result<I> ranges::minmax_element(I first, S last, Comp comp = {}, Proj proj = {}); |
| // |
| // template<forward_range R, class Proj = identity, |
| // indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less> |
| // constexpr ranges::minmax_element_result<borrowed_iterator_t<R>> |
| // ranges::minmax_element(R&& r, Comp comp = {}, Proj proj = {}); |
| |
| #include <algorithm> |
| #include <array> |
| #include <cassert> |
| #include <functional> |
| #include <ranges> |
| |
| #include "almost_satisfies_types.h" |
| #include "test_iterators.h" |
| |
| template <class T> |
| concept HasMinMaxElementR = requires(T t) { std::ranges::minmax_element(t); }; |
| |
| struct NoLessThanOp {}; |
| struct NotTotallyOrdered { |
| int i; |
| bool operator<(const NotTotallyOrdered& o) const { return i < o.i; } |
| }; |
| |
| static_assert(HasMinMaxElementR<int (&)[10]>); // make sure HasMinMaxElementR works with an array |
| static_assert(!HasMinMaxElementR<NoLessThanOp (&)[10]>); |
| static_assert(!HasMinMaxElementR<NotTotallyOrdered (&)[10]>); |
| |
| static_assert(HasMinMaxElementR<std::initializer_list<int>>); // make sure HasMinMaxElementR works with an initializer_list |
| static_assert(!HasMinMaxElementR<std::initializer_list<NoLessThanOp>>); |
| static_assert(!HasMinMaxElementR<std::initializer_list<NotTotallyOrdered>>); |
| static_assert(!HasMinMaxElementR<InputRangeNotDerivedFrom>); |
| static_assert(!HasMinMaxElementR<InputRangeNotIndirectlyReadable>); |
| static_assert(!HasMinMaxElementR<InputRangeNotInputOrOutputIterator>); |
| static_assert(!HasMinMaxElementR<InputRangeNotSentinelSemiregular>); |
| static_assert(!HasMinMaxElementR<InputRangeNotSentinelEqualityComparableWith>); |
| |
| template <class It, class Sent = sentinel_wrapper<It>> |
| concept HasMinMaxElementIt = requires(It it, Sent sent) { std::ranges::minmax_element(it, sent); }; |
| static_assert(HasMinMaxElementIt<int*>); // make sure HasMinMaxElementIt works |
| static_assert(!HasMinMaxElementIt<InputIteratorNotDerivedFrom>); |
| static_assert(!HasMinMaxElementIt<InputIteratorNotIndirectlyReadable>); |
| static_assert(!HasMinMaxElementIt<InputIteratorNotInputOrOutputIterator>); |
| static_assert(!HasMinMaxElementIt<int*, SentinelForNotSemiregular>); |
| static_assert(!HasMinMaxElementIt<int*, SentinelForNotWeaklyEqualityComparableWith>); |
| |
| static_assert(std::is_same_v<std::ranges::minmax_element_result<int>, std::ranges::min_max_result<int>>); |
| |
| template <class It> |
| constexpr void test_iterators(std::initializer_list<int> a, int expectedMin, int expectedMax) { |
| using Expected = std::ranges::minmax_element_result<It>; |
| const int* first = a.begin(); |
| const int* last = a.end(); |
| { |
| std::same_as<Expected> auto it = std::ranges::minmax_element(It(first), It(last)); |
| assert(base(it.min) == first + expectedMin); |
| assert(base(it.max) == first + expectedMax); |
| } |
| { |
| using Sent = sentinel_wrapper<It>; |
| std::same_as<Expected> auto it = std::ranges::minmax_element(It(first), Sent(It(last))); |
| assert(base(it.min) == first + expectedMin); |
| assert(base(it.max) == first + expectedMax); |
| } |
| { |
| auto range = std::ranges::subrange(It(first), It(last)); |
| std::same_as<Expected> auto it = std::ranges::minmax_element(range); |
| assert(base(it.min) == first + expectedMin); |
| assert(base(it.max) == first + expectedMax); |
| } |
| { |
| using Sent = sentinel_wrapper<It>; |
| auto range = std::ranges::subrange(It(first), Sent(It(last))); |
| std::same_as<Expected> auto it = std::ranges::minmax_element(range); |
| assert(base(it.min) == first + expectedMin); |
| assert(base(it.max) == first + expectedMax); |
| } |
| } |
| |
| template <class It> |
| constexpr bool test_iterators() { |
| test_iterators<It>({}, 0, 0); |
| test_iterators<It>({1}, 0, 0); |
| test_iterators<It>({1, 2}, 0, 1); |
| test_iterators<It>({2, 1}, 1, 0); |
| test_iterators<It>({2, 1, 2}, 1, 2); |
| test_iterators<It>({2, 1, 1}, 1, 0); |
| test_iterators<It>({2, 2, 1}, 2, 1); |
| |
| return true; |
| } |
| |
| constexpr void test_borrowed_range_and_sentinel() { |
| int a[] = {7, 6, 1, 3, 5, 1, 2, 4}; |
| |
| std::ranges::minmax_element_result<int*> ret = std::ranges::minmax_element(std::views::all(a)); |
| assert(ret.min == a + 2); |
| assert(ret.max == a + 0); |
| assert(*ret.min == 1); |
| assert(*ret.max == 7); |
| } |
| |
| constexpr void test_comparator() { |
| int a[] = {7, 6, 9, 3, 5, 1, 2, 4}; |
| std::ranges::minmax_element_result<int*> ret = std::ranges::minmax_element(a, std::ranges::greater{}); |
| assert(ret.min == a + 2); |
| assert(ret.max == a + 5); |
| assert(*ret.min == 9); |
| assert(*ret.max == 1); |
| } |
| |
| constexpr void test_projection() { |
| { |
| int a[] = {7, 6, 9, 3, 5, 1, 2, 4}; |
| std::ranges::minmax_element_result<int*> ret = |
| std::ranges::minmax_element(a, std::ranges::less{}, [](int i) { return i == 5 ? -100 : i; }); |
| assert(ret.min == a + 4); |
| assert(ret.max == a + 2); |
| assert(*ret.min == 5); |
| assert(*ret.max == 9); |
| } |
| { |
| int a[] = {7, 6, 9, 3, 5, 1, 2, 4}; |
| std::ranges::minmax_element_result<int*> ret = |
| std::ranges::minmax_element(a, std::less<int*>{}, [](int& i) { return &i; }); |
| assert(ret.min == a + 0); |
| assert(ret.max == a + 7); |
| assert(*ret.min == 7); |
| assert(*ret.max == 4); |
| } |
| } |
| |
| struct Immobile { |
| int i; |
| |
| constexpr Immobile(int i_) : i(i_) {} |
| Immobile(const Immobile&) = delete; |
| Immobile(Immobile&&) = delete; |
| |
| auto operator<=>(const Immobile&) const = default; |
| }; |
| |
| constexpr void test_immobile() { |
| { |
| Immobile arr[]{1, 2, 3}; |
| auto ret = std::ranges::minmax_element(arr); |
| assert(ret.min == arr + 0); |
| assert(ret.max == arr + 2); |
| } |
| { |
| Immobile arr[]{1, 2, 3}; |
| auto ret = std::ranges::minmax_element(arr, arr + 3); |
| assert(ret.min == arr + 0); |
| assert(ret.max == arr + 2); |
| } |
| } |
| |
| constexpr void test_dangling() { |
| int compares = 0; |
| int projections = 0; |
| auto comparator = [&](int a, int b) { |
| ++compares; |
| return a < b; |
| }; |
| auto projection = [&](int a) { |
| ++projections; |
| return a; |
| }; |
| [[maybe_unused]] std::same_as<std::ranges::minmax_element_result<std::ranges::dangling>> auto ret = |
| std::ranges::minmax_element(std::array{1, 2, 3}, comparator, projection); |
| assert(compares == 3); |
| assert(projections == 6); |
| } |
| |
| constexpr bool test() { |
| test_iterators<forward_iterator<const int*>>(); |
| test_iterators<bidirectional_iterator<const int*>>(); |
| test_iterators<random_access_iterator<const int*>>(); |
| test_iterators<contiguous_iterator<const int*>>(); |
| test_iterators<const int*>(); |
| test_iterators<int*>(); |
| |
| test_borrowed_range_and_sentinel(); |
| test_comparator(); |
| test_projection(); |
| test_dangling(); |
| |
| { // check that std::invoke is used |
| { |
| struct S { |
| int i; |
| }; |
| S b[3] = {S{2}, S{1}, S{3}}; |
| std::same_as<std::ranges::minmax_element_result<S*>> auto ret = std::ranges::minmax_element(b, {}, &S::i); |
| assert(ret.min->i == 1); |
| assert(ret.max->i == 3); |
| assert(ret.min == b + 1); |
| assert(ret.max == b + 2); |
| } |
| { |
| struct S { |
| int i; |
| }; |
| S b[3] = {S{2}, S{1}, S{3}}; |
| std::same_as<std::ranges::minmax_element_result<S*>> auto ret = std::ranges::minmax_element(b, b + 3, {}, &S::i); |
| assert(ret.min->i == 1); |
| assert(ret.max->i == 3); |
| assert(ret.min == b + 1); |
| assert(ret.max == b + 2); |
| } |
| } |
| |
| { // check that the leftmost value for min an rightmost for max are returned |
| { |
| struct S { |
| int comp; |
| int other; |
| }; |
| S a[] = { {0, 0}, {0, 2}, {0, 1} }; |
| auto ret = std::ranges::minmax_element(a, a + 3, {}, &S::comp); |
| assert(ret.min->comp == 0); |
| assert(ret.max->comp == 0); |
| assert(ret.min->other == 0); |
| assert(ret.max->other == 1); |
| } |
| { |
| struct S { |
| int comp; |
| int other; |
| }; |
| S a[] = { {0, 0}, {0, 2}, {0, 1} }; |
| auto ret = std::ranges::minmax_element(a, {}, &S::comp); |
| assert(ret.min->comp == 0); |
| assert(ret.max->comp == 0); |
| assert(ret.min->other == 0); |
| assert(ret.max->other == 1); |
| } |
| } |
| |
| { // check that an empty range works |
| { |
| std::array<int, 0> a = {}; |
| auto ret = std::ranges::minmax_element(a.begin(), a.end()); |
| assert(ret.min == a.begin()); |
| assert(ret.max == a.begin()); |
| } |
| { |
| std::array<int, 0> a = {}; |
| auto ret = std::ranges::minmax_element(a); |
| assert(ret.min == a.begin()); |
| assert(ret.max == a.begin()); |
| } |
| } |
| |
| { // check in ascending order |
| { |
| int a[] = {1, 2, 3}; |
| auto ret = std::ranges::minmax_element(a, a + 3); |
| assert(ret.min == a + 0); |
| assert(ret.max == a + 2); |
| assert(*ret.min == 1); |
| assert(*ret.max == 3); |
| } |
| { |
| int a[] = {1, 2, 3}; |
| auto ret = std::ranges::minmax_element(a); |
| assert(ret.min == a + 0); |
| assert(ret.max == a + 2); |
| assert(*ret.min == 1); |
| assert(*ret.max == 3); |
| } |
| } |
| |
| { // check in descending order |
| { |
| int a[] = {3, 2, 1}; |
| auto ret = std::ranges::minmax_element(a, a + 3); |
| assert(ret.min == a + 2); |
| assert(ret.max == a + 0); |
| assert(*ret.min == 1); |
| assert(*ret.max == 3); |
| } |
| { |
| int a[] = {3, 2, 1}; |
| auto ret = std::ranges::minmax_element(a); |
| assert(ret.min == a + 2); |
| assert(ret.max == a + 0); |
| assert(*ret.min == 1); |
| assert(*ret.max == 3); |
| } |
| } |
| |
| return true; |
| } |
| |
| int main(int, char**) { |
| test(); |
| static_assert(test()); |
| |
| return 0; |
| } |