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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
//
//===----------------------------------------------------------------------===//
// <string>
// UNSUPPORTED: c++03, c++11, c++14
// template<class charT,
// class traits,
// class Allocator = allocator<charT>
// >
// basic_string(basic_string_view<charT, traits>, const Allocator& = Allocator())
// -> basic_string<charT, traits, Allocator>;
//
// The deduction guide shall not participate in overload resolution if Allocator
// is a type that does not qualify as an allocator.
#include <string>
#include <string_view>
#include <iterator>
#include <memory>
#include <type_traits>
#include <cassert>
#include <cstddef>
#include "test_macros.h"
#include "test_allocator.h"
#include "min_allocator.h"
template <class StringView, class Allocator, class = void>
struct CanDeduce : std::false_type { };
template <class StringView, class Allocator>
struct CanDeduce<StringView, Allocator, decltype((void)
std::basic_string{std::declval<StringView>(), std::declval<Allocator>()}
)> : std::true_type { };
struct NotAnAllocator { };
static_assert( CanDeduce<std::string_view, std::allocator<char>>::value);
static_assert(!CanDeduce<std::string_view, NotAnAllocator>::value);
TEST_CONSTEXPR_CXX20 bool test() {
{
std::string_view sv = "12345678901234";
std::basic_string s1(sv);
using S = decltype(s1); // what type did we get?
static_assert(std::is_same_v<S::value_type, char>, "");
static_assert(std::is_same_v<S::traits_type, std::char_traits<char>>, "");
static_assert(std::is_same_v<S::allocator_type, std::allocator<char>>, "");
assert(s1.size() == sv.size());
assert(s1.compare(0, s1.size(), sv.data(), s1.size()) == 0);
}
{
std::string_view sv = "12345678901234";
std::basic_string s1{sv, std::allocator<char>{}};
using S = decltype(s1); // what type did we get?
static_assert(std::is_same_v<S::value_type, char>, "");
static_assert(std::is_same_v<S::traits_type, std::char_traits<char>>, "");
static_assert(std::is_same_v<S::allocator_type, std::allocator<char>>, "");
assert(s1.size() == sv.size());
assert(s1.compare(0, s1.size(), sv.data(), s1.size()) == 0);
}
#ifndef TEST_HAS_NO_WIDE_CHARACTERS
{
std::wstring_view sv = L"12345678901234";
std::basic_string s1{sv, test_allocator<wchar_t>{}};
using S = decltype(s1); // what type did we get?
static_assert(std::is_same_v<S::value_type, wchar_t>, "");
static_assert(std::is_same_v<S::traits_type, std::char_traits<wchar_t>>, "");
static_assert(std::is_same_v<S::allocator_type, test_allocator<wchar_t>>, "");
assert(s1.size() == sv.size());
assert(s1.compare(0, s1.size(), sv.data(), s1.size()) == 0);
}
#endif
#ifndef TEST_HAS_NO_CHAR8_T
{
std::u8string_view sv = u8"12345678901234";
std::basic_string s1{sv, min_allocator<char8_t>{}};
using S = decltype(s1); // what type did we get?
static_assert(std::is_same_v<S::value_type, char8_t>, "");
static_assert(std::is_same_v<S::traits_type, std::char_traits<char8_t>>, "");
static_assert(std::is_same_v<S::allocator_type, min_allocator<char8_t>>, "");
assert(s1.size() == sv.size());
assert(s1.compare(0, s1.size(), sv.data(), s1.size()) == 0);
}
#endif
{
std::u16string_view sv = u"12345678901234";
std::basic_string s1{sv, min_allocator<char16_t>{}};
using S = decltype(s1); // what type did we get?
static_assert(std::is_same_v<S::value_type, char16_t>, "");
static_assert(std::is_same_v<S::traits_type, std::char_traits<char16_t>>, "");
static_assert(std::is_same_v<S::allocator_type, min_allocator<char16_t>>, "");
assert(s1.size() == sv.size());
assert(s1.compare(0, s1.size(), sv.data(), s1.size()) == 0);
}
{
std::u32string_view sv = U"12345678901234";
std::basic_string s1{sv, explicit_allocator<char32_t>{}};
using S = decltype(s1); // what type did we get?
static_assert(std::is_same_v<S::value_type, char32_t>, "");
static_assert(std::is_same_v<S::traits_type, std::char_traits<char32_t>>, "");
static_assert(std::is_same_v<S::allocator_type, explicit_allocator<char32_t>>, "");
assert(s1.size() == sv.size());
assert(s1.compare(0, s1.size(), sv.data(), s1.size()) == 0);
}
return true;
}
int main(int, char**)
{
test();
#if TEST_STD_VER > 17
static_assert(test());
#endif
return 0;
}
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