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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
// constexpr auto size() requires sized_range<R>
// constexpr auto size() const requires sized_range<const R>
#include <ranges>
#include <array>
#include <cassert>
#include <concepts>
#include "test_iterators.h"
#include "test_macros.h"
template <class T>
concept HasSize = requires (T t) {
t.size();
};
constexpr bool test()
{
{
struct SubtractableIters {
forward_iterator<int*> begin();
sized_sentinel<forward_iterator<int*>> end();
};
using OwningView = std::ranges::owning_view<SubtractableIters>;
static_assert(std::ranges::sized_range<OwningView&>);
static_assert(!std::ranges::range<const OwningView&>); // no begin/end
static_assert(HasSize<OwningView&>);
static_assert(HasSize<OwningView&&>);
static_assert(!HasSize<const OwningView&>);
static_assert(!HasSize<const OwningView&&>);
}
{
struct NoSize {
bidirectional_iterator<int*> begin();
bidirectional_iterator<int*> end();
};
using OwningView = std::ranges::owning_view<NoSize>;
static_assert(!HasSize<OwningView&>);
static_assert(!HasSize<OwningView&&>);
static_assert(!HasSize<const OwningView&>);
static_assert(!HasSize<const OwningView&&>);
}
{
struct SizeMember {
bidirectional_iterator<int*> begin();
bidirectional_iterator<int*> end();
int size() const;
};
using OwningView = std::ranges::owning_view<SizeMember>;
static_assert(std::ranges::sized_range<OwningView&>);
static_assert(!std::ranges::range<const OwningView&>); // no begin/end
static_assert(HasSize<OwningView&>);
static_assert(HasSize<OwningView&&>);
static_assert(!HasSize<const OwningView&>); // not a range, therefore no size()
static_assert(!HasSize<const OwningView&&>);
}
{
// Test an empty view.
int a[] = {1};
auto ov = std::ranges::owning_view(std::ranges::subrange(a, a));
assert(ov.size() == 0);
assert(std::as_const(ov).size() == 0);
}
{
// Test a non-empty view.
int a[] = {1};
auto ov = std::ranges::owning_view(std::ranges::subrange(a, a+1));
assert(ov.size() == 1);
assert(std::as_const(ov).size() == 1);
}
{
// Test a non-view.
std::array<int, 2> a = {1, 2};
auto ov = std::ranges::owning_view(std::move(a));
assert(ov.size() == 2);
assert(std::as_const(ov).size() == 2);
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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