82 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9// <string>10 11// const_reference at(size_type pos) const; // constexpr since C++2012// reference at(size_type pos); // constexpr since C++2013 14#include <string>15#include <stdexcept>16#include <cassert>17 18#include "min_allocator.h"19 20#include "make_string.h"21#include "test_macros.h"22#include "type_algorithms.h"23 24template <class S>25TEST_CONSTEXPR_CXX20 void test(S s, typename S::size_type pos) {26 const S& cs = s;27 if (pos < s.size()) {28 assert(s.at(pos) == s[pos]);29 assert(cs.at(pos) == cs[pos]);30 }31#ifndef TEST_HAS_NO_EXCEPTIONS32 else if (!TEST_IS_CONSTANT_EVALUATED) {33 try {34 TEST_IGNORE_NODISCARD s.at(pos);35 assert(false);36 } catch (std::out_of_range&) {37 assert(pos >= s.size());38 }39 try {40 TEST_IGNORE_NODISCARD cs.at(pos);41 assert(false);42 } catch (std::out_of_range&) {43 assert(pos >= s.size());44 }45 }46#endif47}48 49template <class S>50TEST_CONSTEXPR_CXX20 void test_string() {51 test(S(), 0);52 test(S(MAKE_CSTRING(typename S::value_type, "123")), 0);53 test(S(MAKE_CSTRING(typename S::value_type, "123")), 1);54 test(S(MAKE_CSTRING(typename S::value_type, "123")), 2);55 test(S(MAKE_CSTRING(typename S::value_type, "123")), 3);56}57 58struct TestCaller {59 template <class T>60 TEST_CONSTEXPR_CXX20 void operator()() {61 test_string<std::basic_string<T> >();62#if TEST_STD_VER >= 1163 test_string<std::basic_string<T, std::char_traits<T>, min_allocator<T> > >();64#endif65 }66};67 68TEST_CONSTEXPR_CXX20 bool test() {69 types::for_each(types::character_types(), TestCaller());70 71 return true;72}73 74int main(int, char**) {75 test();76#if TEST_STD_VER > 1777 static_assert(test());78#endif79 80 return 0;81}82