--- /dev/null
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_EQUAL_H
+#define _LIBCPP___ALGORITHM_RANGES_EQUAL_H
+
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/distance.h>
+#include <__iterator/indirectly_comparable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __equal {
+struct __fn {
+private:
+ template <class _Iter1, class _Sent1,
+ class _Iter2, class _Sent2,
+ class _Pred,
+ class _Proj1,
+ class _Proj2>
+ _LIBCPP_HIDE_FROM_ABI constexpr static
+ bool __equal_impl(_Iter1 __first1, _Sent1 __last1,
+ _Iter2 __first2, _Sent2 __last2,
+ _Pred& __pred,
+ _Proj1& __proj1,
+ _Proj2& __proj2) {
+ while (__first1 != __last1 && __first2 != __last2) {
+ if (!std::invoke(__pred, std::invoke(__proj1, *__first1), std::invoke(__proj2, *__first2)))
+ return false;
+ ++__first1;
+ ++__first2;
+ }
+ return __first1 == __last1 && __first2 == __last2;
+ }
+
+public:
+
+ template <input_iterator _Iter1, sentinel_for<_Iter1> _Sent1,
+ input_iterator _Iter2, sentinel_for<_Iter2> _Sent2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
+ _LIBCPP_HIDE_FROM_ABI constexpr
+ bool operator()(_Iter1 __first1, _Sent1 __last1,
+ _Iter2 __first2, _Sent2 __last2,
+ _Pred __pred = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ if constexpr (sized_sentinel_for<_Sent1, _Iter1> && sized_sentinel_for<_Sent2, _Iter2>) {
+ if (__last1 - __first1 != __last2 - __first2)
+ return false;
+ }
+ return __equal_impl(std::move(__first1), std::move(__last1),
+ std::move(__first2), std::move(__last2),
+ __pred,
+ __proj1,
+ __proj2);
+ }
+
+ template <input_range _Range1,
+ input_range _Range2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_comparable<iterator_t<_Range1>, iterator_t<_Range2>, _Pred, _Proj1, _Proj2>
+ _LIBCPP_HIDE_FROM_ABI constexpr
+ bool operator()(_Range1&& __range1,
+ _Range2&& __range2,
+ _Pred __pred = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ if constexpr (sized_range<_Range1> && sized_range<_Range2>) {
+ if (ranges::distance(__range1) != ranges::distance(__range2))
+ return false;
+ }
+ return __equal_impl(ranges::begin(__range1), ranges::end(__range1),
+ ranges::begin(__range2), ranges::end(__range2),
+ __pred,
+ __proj1,
+ __proj2);
+ return false;
+ }
+};
+} // namespace __equal
+
+inline namespace __cpo {
+ inline constexpr auto equal = __equal::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
+
+#endif // _LIBCPP___ALGORITHM_RANGES_EQUAL_H
--- /dev/null
+//===----------------------------------------------------------------------===//
+//
+// 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
+// UNSUPPORTED: libcpp-has-no-incomplete-ranges
+
+// template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
+// class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
+// requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
+// constexpr bool ranges::equal(I1 first1, S1 last1, I2 first2, S2 last2,
+// Pred pred = {},
+// Proj1 proj1 = {}, Proj2 proj2 = {});
+// template<input_range R1, input_range R2, class Pred = ranges::equal_to,
+// class Proj1 = identity, class Proj2 = identity>
+// requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
+// constexpr bool ranges::equal(R1&& r1, R2&& r2, Pred pred = {},
+// Proj1 proj1 = {}, Proj2 proj2 = {});
+
+#include <algorithm>
+#include <cassert>
+#include <concepts>
+#include <functional>
+#include <ranges>
+
+#include "almost_satisfies_types.h"
+#include "test_iterators.h"
+
+template <class Iter1, class Sent1 = sentinel_wrapper<Iter1>,
+ class Iter2 = Iter1, class Sent2 = sentinel_wrapper<Iter2>>
+concept HasEqualIt = requires (Iter1 first1, Sent1 last1, Iter2 first2, Sent2 last2) {
+ std::ranges::equal(first1, last1, first2, last2);
+};
+
+static_assert(HasEqualIt<int*>);
+static_assert(!HasEqualIt<InputIteratorNotDerivedFrom>);
+static_assert(!HasEqualIt<InputIteratorNotIndirectlyReadable>);
+static_assert(!HasEqualIt<InputIteratorNotInputOrOutputIterator>);
+static_assert(!HasEqualIt<int*, int*, InputIteratorNotDerivedFrom>);
+static_assert(!HasEqualIt<int*, int*, InputIteratorNotIndirectlyReadable>);
+static_assert(!HasEqualIt<int*, int*, InputIteratorNotInputOrOutputIterator>);
+static_assert(!HasEqualIt<int*, SentinelForNotSemiregular>);
+static_assert(!HasEqualIt<int*, SentinelForNotWeaklyEqualityComparableWith>);
+static_assert(!HasEqualIt<int*, int*, int*, SentinelForNotSemiregular>);
+static_assert(!HasEqualIt<int*, int*, int*, SentinelForNotWeaklyEqualityComparableWith>);
+static_assert(!HasEqualIt<int*, int*, int**>);
+
+template <class Range1, class Range2>
+concept HasEqualR = requires (Range1 range1, Range2 range2) {
+ std::ranges::equal(range1, range2);
+};
+
+static_assert(HasEqualR<UncheckedRange<int*>, UncheckedRange<int*>>);
+static_assert(!HasEqualR<InputRangeNotDerivedFrom, UncheckedRange<int*>>);
+static_assert(!HasEqualR<InputRangeNotIndirectlyReadable, UncheckedRange<int*>>);
+static_assert(!HasEqualR<InputRangeNotInputOrOutputIterator, UncheckedRange<int*>>);
+static_assert(!HasEqualR<InputRangeNotSentinelSemiregular, UncheckedRange<int*>>);
+static_assert(!HasEqualR<InputRangeNotSentinelEqualityComparableWith, UncheckedRange<int*>>);
+static_assert(!HasEqualR<UncheckedRange<int*>, InputRangeNotDerivedFrom>);
+static_assert(!HasEqualR<UncheckedRange<int*>, InputRangeNotIndirectlyReadable>);
+static_assert(!HasEqualR<UncheckedRange<int*>, InputRangeNotInputOrOutputIterator>);
+static_assert(!HasEqualR<UncheckedRange<int*>, InputRangeNotSentinelSemiregular>);
+static_assert(!HasEqualR<UncheckedRange<int*>, InputRangeNotSentinelEqualityComparableWith>);
+static_assert(!HasEqualR<UncheckedRange<int*>, UncheckedRange<int**>>);
+
+template <class Iter1, class Sent1, class Iter2, class Sent2 = Iter2>
+constexpr void test_iterators() {
+ { // simple test
+ {
+ int a[] = {1, 2, 3, 4};
+ int b[] = {1, 2, 3, 4};
+ std::same_as<bool> decltype(auto) ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a + 4)),
+ Iter2(b), Sent2(Iter2(b + 4)));
+ assert(ret);
+ }
+ {
+ int a[] = {1, 2, 3, 4};
+ int b[] = {1, 2, 3, 4};
+ auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a + 4)));
+ auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b + 4)));
+ std::same_as<bool> decltype(auto) ret = std::ranges::equal(range1, range2);
+ assert(ret);
+ }
+ }
+
+ { // check that the predicate is used (return true)
+ {
+ int a[] = {1, 2, 3, 4};
+ int b[] = {2, 3, 4, 5};
+ auto ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a + 4)), Iter2(b), Sent2(Iter2(b + 4)),
+ [](int l, int r) { return l != r; });
+ assert(ret);
+ }
+ {
+ int a[] = {1, 2, 3, 4};
+ int b[] = {2, 3, 4, 5};
+ auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a + 4)));
+ auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b + 4)));
+ auto ret = std::ranges::equal(range1, range2, [](int l, int r) { return l != r; });
+ assert(ret);
+ }
+ }
+
+ { // check that the predicate is used (return false)
+ {
+ int a[] = {1, 2, 3, 4};
+ int b[] = {2, 3, 3, 5};
+ auto ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a + 4)), Iter2(b), Sent2(Iter2(b + 4)),
+ [](int l, int r) { return l != r; });
+ assert(!ret);
+ }
+ {
+ int a[] = {1, 2, 3, 4};
+ int b[] = {2, 3, 3, 5};
+ auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a + 4)));
+ auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b + 4)));
+ auto ret = std::ranges::equal(range1, range2, [](int l, int r) { return l != r; });
+ assert(!ret);
+ }
+ }
+
+ { // check that the projections are used
+ {
+ int a[] = {1, 2, 3, 4, 5};
+ int b[] = {6, 10, 14, 18, 22};
+ auto ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a + 5)),
+ Iter2(b), Sent2(Iter2(b + 5)),
+ {},
+ [](int i) { return i * 4; },
+ [](int i) { return i - 2; });
+ assert(ret);
+ }
+ {
+ int a[] = {1, 2, 3, 4, 5};
+ int b[] = {6, 10, 14, 18, 22};
+ auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a + 5)));
+ auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b + 5)));
+ auto ret = std::ranges::equal(range1,
+ range2,
+ {},
+ [](int i) { return i * 4; },
+ [](int i) { return i - 2; });
+ assert(ret);
+ }
+ }
+
+ { // check that different sized ranges work
+ {
+ int a[] = {4, 3, 2, 1};
+ int b[] = {4, 3, 2, 1, 5, 6, 7};
+ auto ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a + 4)), Iter2(b), Sent2(Iter2(b + 7)));
+ assert(!ret);
+ }
+ {
+ int a[] = {4, 3, 2, 1};
+ int b[] = {4, 3, 2, 1, 5, 6, 7};
+ auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a + 4)));
+ auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b + 7)));
+ auto ret = std::ranges::equal(range1, range2);
+ assert(!ret);
+ }
+ }
+
+ { // check that two ranges with the same size but different values are different
+ {
+ int a[] = {4, 6, 34, 76, 5};
+ int b[] = {4, 6, 34, 67, 5};
+ auto ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a + 5)), Iter2(b), Sent2(Iter2(b + 5)));
+ assert(!ret);
+ }
+ {
+ int a[] = {4, 6, 34, 76, 5};
+ int b[] = {4, 6, 34, 67, 5};
+ auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a + 5)));
+ auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b + 5)));
+ auto ret = std::ranges::equal(range1, range2);
+ assert(!ret);
+ }
+ }
+
+ { // check that two empty ranges work
+ {
+ int a[] = {};
+ int b[] = {};
+ auto ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a)), Iter2(b), Sent2(Iter2(b)));
+ assert(ret);
+ }
+ {
+ int a[] = {};
+ int b[] = {};
+ auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a)));
+ auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b)));
+ auto ret = std::ranges::equal(range1, range2);
+ assert(ret);
+ }
+ }
+
+ { // check that it works with the first range empty
+ {
+ int a[] = {};
+ int b[] = {1, 2};
+ auto ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a)), Iter2(b), Sent2(Iter2(b + 2)));
+ assert(!ret);
+ }
+ {
+ int a[] = {};
+ int b[] = {1, 2};
+ auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a)));
+ auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b + 2)));
+ auto ret = std::ranges::equal(range1, range2);
+ assert(!ret);
+ }
+ }
+
+ { // check that it works with the second range empty
+ {
+ int a[] = {1, 2};
+ int b[] = {};
+ auto ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a + 2)), Iter2(b), Sent2(Iter2(b)));
+ assert(!ret);
+ }
+ {
+ int a[] = {1, 2};
+ int b[] = {};
+ auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a + 2)));
+ auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b)));
+ auto ret = std::ranges::equal(range1, range2);
+ assert(!ret);
+ }
+ }
+}
+
+template<class Iter1, class Sent1 = Iter1>
+constexpr void test_iterators2() {
+ test_iterators<Iter1, Sent1, cpp17_input_iterator<int*>, sentinel_wrapper<cpp17_input_iterator<int*>>>();
+ test_iterators<Iter1, Sent1, cpp20_input_iterator<int*>, sentinel_wrapper<cpp20_input_iterator<int*>>>();
+ test_iterators<Iter1, Sent1, forward_iterator<int*>>();
+ test_iterators<Iter1, Sent1, bidirectional_iterator<int*>>();
+ test_iterators<Iter1, Sent1, random_access_iterator<int*>>();
+ test_iterators<Iter1, Sent1, contiguous_iterator<int*>>();
+ test_iterators<Iter1, Sent1, int*>();
+ test_iterators<Iter1, Sent1, const int*>();
+}
+
+constexpr bool test() {
+ test_iterators2<cpp17_input_iterator<int*>, sentinel_wrapper<cpp17_input_iterator<int*>>>();
+ test_iterators2<cpp20_input_iterator<int*>, sentinel_wrapper<cpp20_input_iterator<int*>>>();
+ test_iterators2<forward_iterator<int*>>();
+ test_iterators2<bidirectional_iterator<int*>>();
+ test_iterators2<random_access_iterator<int*>>();
+ test_iterators2<contiguous_iterator<int*>>();
+ test_iterators2<int*>();
+ test_iterators2<const int*>();
+
+ { // check that std::invoke is used
+ struct S {
+ constexpr S(int i_) : i(i_) {}
+ constexpr bool equal(int o) { return i == o; }
+ constexpr S& identity() { return *this; }
+ int i;
+ };
+ {
+ S a[] = {7, 8, 9};
+ S b[] = {7, 8, 9};
+ auto ret = std::ranges::equal(a, a + 3, b, b + 3, &S::equal, &S::identity, &S::i);
+ assert(ret);
+ }
+ {
+ S a[] = {7, 8, 9};
+ S b[] = {7, 8, 9};
+ auto ret = std::ranges::equal(a, b, &S::equal, &S::identity, &S::i);
+ assert(ret);
+ }
+ }
+
+ { // check that the complexity requirements are met
+ { // different size
+ {
+ int a[] = {1, 2, 3};
+ int b[] = {1, 2, 3, 4};
+ int predCount = 0;
+ int projCount = 0;
+ auto pred = [&](int l, int r) { ++predCount; return l == r; };
+ auto proj = [&](int i) { ++projCount; return i; };
+ auto ret = std::ranges::equal(a, a + 3, b, b + 4, pred, proj, proj);
+ assert(!ret);
+ assert(predCount == 0);
+ assert(projCount == 0);
+ }
+ {
+ int a[] = {1, 2, 3};
+ int b[] = {1, 2, 3, 4};
+ int predCount = 0;
+ int projCount = 0;
+ auto pred = [&](int l, int r) { ++predCount; return l == r; };
+ auto proj = [&](int i) { ++projCount; return i; };
+ auto ret = std::ranges::equal(a, b, pred, proj, proj);
+ assert(!ret);
+ assert(predCount == 0);
+ assert(projCount == 0);
+ }
+ }
+
+ { // not a sized sentinel
+ {
+ int a[] = {1, 2, 3};
+ int b[] = {1, 2, 3, 4};
+ int predCount = 0;
+ int projCount = 0;
+ auto pred = [&](int l, int r) { ++predCount; return l == r; };
+ auto proj = [&](int i) { ++projCount; return i; };
+ auto ret = std::ranges::equal(a, sentinel_wrapper(a + 3), b, sentinel_wrapper(b + 4), pred, proj, proj);
+ assert(!ret);
+ assert(predCount <= 4);
+ assert(projCount <= 7);
+ }
+ {
+ int a[] = {1, 2, 3};
+ int b[] = {1, 2, 3, 4};
+ int predCount = 0;
+ int projCount = 0;
+ auto pred = [&](int l, int r) { ++predCount; return l == r; };
+ auto proj = [&](int i) { ++projCount; return i; };
+ auto range1 = std::ranges::subrange(a, sentinel_wrapper(a + 3));
+ auto range2 = std::ranges::subrange(b, sentinel_wrapper(b + 4));
+ auto ret = std::ranges::equal(range1, range2, pred, proj, proj);
+ assert(!ret);
+ assert(predCount <= 4);
+ assert(projCount <= 7);
+ }
+ }
+
+ { // same size
+ {
+ int a[] = {1, 2, 3};
+ int b[] = {1, 2, 3};
+ int predCount = 0;
+ int projCount = 0;
+ auto pred = [&](int l, int r) { ++predCount; return l == r; };
+ auto proj = [&](int i) { ++projCount; return i; };
+ auto ret = std::ranges::equal(a, a + 3, b, b + 3, pred, proj, proj);
+ assert(ret);
+ assert(predCount == 3);
+ assert(projCount == 6);
+ }
+ {
+ int a[] = {1, 2, 3};
+ int b[] = {1, 2, 3};
+ int predCount = 0;
+ int projCount = 0;
+ auto pred = [&](int l, int r) { ++predCount; return l == r; };
+ auto proj = [&](int i) { ++projCount; return i; };
+ auto ret = std::ranges::equal(a, b, pred, proj, proj);
+ assert(ret);
+ assert(predCount == 3);
+ assert(projCount == 6);
+ }
+ }
+ }
+
+ return true;
+}
+
+int main(int, char**) {
+ test();
+ static_assert(test());
+
+ return 0;
+}