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-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 // <string>
10
11 // const_reference at(size_type pos) const; // constexpr since C++20
12 // reference at(size_type pos); // constexpr since C++20
13
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
24 template <class S>
test(S s,typename S::size_type pos)25 TEST_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_EXCEPTIONS
32 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 #endif
47 }
48
49 template <class S>
test_string()50 TEST_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
58 struct TestCaller {
59 template <class T>
operator ()TestCaller60 TEST_CONSTEXPR_CXX20 void operator()() {
61 test_string<std::basic_string<T> >();
62 #if TEST_STD_VER >= 11
63 test_string<std::basic_string<T, std::char_traits<T>, min_allocator<T> > >();
64 #endif
65 }
66 };
67
test()68 TEST_CONSTEXPR_CXX20 bool test() {
69 types::for_each(types::character_types(), TestCaller());
70
71 return true;
72 }
73
main(int,char **)74 int main(int, char**) {
75 test();
76 #if TEST_STD_VER > 17
77 static_assert(test());
78 #endif
79
80 return 0;
81 }
82