Nikolas Klauser 425620ccdd [libc++] Implement P0980R1 (constexpr std::string)
Reviewed By: #libc, ldionne

Spies: daltenty, sdasgup3, ldionne, arichardson, MTC, ChuanqiXu, mehdi_amini, shauheen, antiagainst, nicolasvasilache, arpith-jacob, mgester, lucyrfox, aartbik, liufengdb, stephenneuendorffer, Joonsoo, grosul1, Kayjukh, jurahul, msifontes, tatianashp, rdzhabarov, teijeong, cota, dcaballe, Chia-hungDuan, wrengr, wenzhicui, arphaman, Mordante, miscco, Quuxplusone, smeenai, libcxx-commits

Differential Revision: https://reviews.llvm.org/D110598
2022-04-27 12:25:34 +02:00

91 lines
1.9 KiB
C++

//===----------------------------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
// XFAIL: LIBCXX-AIX-FIXME
// <string>
// const_reference at(size_type pos) const; // constexpr since C++20
// reference at(size_type pos); // constexpr since C++20
#include <string>
#include <stdexcept>
#include <cassert>
#include "min_allocator.h"
#include "test_macros.h"
template <class S>
TEST_CONSTEXPR_CXX20 void
test(S s, typename S::size_type pos)
{
const S& cs = s;
if (pos < s.size())
{
assert(s.at(pos) == s[pos]);
assert(cs.at(pos) == cs[pos]);
}
#ifndef TEST_HAS_NO_EXCEPTIONS
else if (!TEST_IS_CONSTANT_EVALUATED)
{
try
{
TEST_IGNORE_NODISCARD s.at(pos);
assert(false);
}
catch (std::out_of_range&)
{
assert(pos >= s.size());
}
try
{
TEST_IGNORE_NODISCARD cs.at(pos);
assert(false);
}
catch (std::out_of_range&)
{
assert(pos >= s.size());
}
}
#endif
}
TEST_CONSTEXPR_CXX20 bool test() {
{
typedef std::string S;
test(S(), 0);
test(S("123"), 0);
test(S("123"), 1);
test(S("123"), 2);
test(S("123"), 3);
}
#if TEST_STD_VER >= 11
{
typedef std::basic_string<char, std::char_traits<char>, min_allocator<char>> S;
test(S(), 0);
test(S("123"), 0);
test(S("123"), 1);
test(S("123"), 2);
test(S("123"), 3);
}
#endif
return true;
}
int main(int, char**)
{
test();
#if TEST_STD_VER > 17
static_assert(test());
#endif
return 0;
}