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//===----------------------------------------------------------------------===//
//
// 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, c++20
// constexpr auto end()
// constexpr auto end() const
#include <array>
#include <cassert>
#include <ranges>
#include "test_iterators.h"
struct DefaultConstructibleView : std::ranges::view_base {
int* begin() const;
int* end() const;
};
struct CVCallView : std::ranges::view_base {
mutable bool const_called = false;
mutable int i[1];
constexpr int* begin() {
const_called = false;
return i;
}
constexpr int* begin() const {
const_called = true;
return i;
}
constexpr int* end() {
const_called = false;
return i + 1;
}
constexpr int* end() const {
const_called = true;
return i + 1;
}
};
struct NonConstCommonRange : std::ranges::view_base {
int* begin();
int* end();
int* begin() const;
sentinel_wrapper<int*> end() const;
};
struct NonConstView : std::ranges::view_base {
int* begin();
int* end();
};
template <class T>
concept HasEnd = requires(T t) { t.end(); };
static_assert(HasEnd<std::ranges::as_rvalue_view<DefaultConstructibleView>>);
static_assert(HasEnd<const std::ranges::as_rvalue_view<DefaultConstructibleView>>);
static_assert(HasEnd<std::ranges::as_rvalue_view<NonConstView>>);
static_assert(!HasEnd<const std::ranges::as_rvalue_view<NonConstView>>);
static_assert(std::is_same_v<decltype(std::declval<std::ranges::as_rvalue_view<DefaultConstructibleView>>().end()),
std::move_iterator<int*>>);
static_assert(std::is_same_v<decltype(std::declval<const std::ranges::as_rvalue_view<NonConstCommonRange>>().end()),
std::move_sentinel<sentinel_wrapper<int*>>>);
template <class Iter, class Sent, bool is_common>
constexpr void test_range() {
using Expected = std::conditional_t<is_common, std::move_iterator<Sent>, std::move_sentinel<Sent>>;
int a[] = {1, 2};
std::ranges::subrange range(Iter(std::begin(a)), Sent(Iter(std::end(a))));
std::ranges::as_rvalue_view view(std::move(range));
std::same_as<Expected> decltype(auto) iter = view.end();
assert(base(base(iter.base())) == std::end(a));
}
template <class Iter, class Sent>
class WrapRange {
Iter iter_;
Sent sent_;
public:
constexpr WrapRange(Iter iter, Sent sent) : iter_(std::move(iter)), sent_(std::move(sent)) {}
constexpr Iter begin() const { return iter_; }
constexpr Sent end() const { return sent_; }
};
template <class Iter, class Sent>
WrapRange(Iter, Sent) -> WrapRange<Iter, Sent>;
template <class Iter, class Sent, bool is_common>
constexpr void test_const_range() {
using Expected = std::conditional_t<is_common, std::move_iterator<Sent>, std::move_sentinel<Sent>>;
int a[] = {1, 2};
auto range = WrapRange{Iter(a), Sent(Iter(a + 2))};
const std::ranges::as_rvalue_view view(std::move(range));
std::same_as<Expected> decltype(auto) iter = view.end();
assert(base(base(iter.base())) == std::end(a));
}
struct move_iterator_view : std::ranges::view_base {
constexpr std::move_iterator<int*> begin() const { return {}; }
constexpr std::move_iterator<int*> end() const { return {}; }
};
constexpr bool test() {
test_range<cpp17_input_iterator<int*>, sentinel_wrapper<cpp17_input_iterator<int*>>, false>();
test_range<cpp17_input_iterator<int*>, sized_sentinel<cpp17_input_iterator<int*>>, false>();
test_range<cpp20_input_iterator<int*>, sentinel_wrapper<cpp20_input_iterator<int*>>, false>();
test_range<cpp20_input_iterator<int*>, sized_sentinel<cpp20_input_iterator<int*>>, false>();
types::for_each(types::forward_iterator_list<int*>{}, []<class Iter> {
test_range<Iter, Iter, true>();
test_range<Iter, sentinel_wrapper<Iter>, false>();
test_range<Iter, sized_sentinel<Iter>, false>();
});
{
std::ranges::as_rvalue_view view(CVCallView{});
(void)view.end();
assert(view.base().const_called);
}
{ // check that with a std::move_iterator begin() doesn't return move_iterator<move_iterator<T>>
std::ranges::as_rvalue_view view{move_iterator_view{}};
std::same_as<std::move_iterator<int*>> decltype(auto) it = view.end();
assert(it == std::move_iterator<int*>{});
}
return true;
}
int main(int, char**) {
test();
// gcc cannot have mutable member in constant expression
#if !defined(TEST_COMPILER_GCC)
static_assert(test());
#endif
return 0;
}
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