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 charT* c_str() const; // constexpr since C++20
12 
13 #include <string>
14 #include <cassert>
15 
16 #include "test_macros.h"
17 #include "min_allocator.h"
18 
19 template <class S>
20 TEST_CONSTEXPR_CXX20 void
21 test(const S& s)
22 {
23     typedef typename S::traits_type T;
24     const typename S::value_type* str = s.c_str();
25     if (s.size() > 0)
26     {
27         assert(T::compare(str, &s[0], s.size()) == 0);
28         assert(T::eq(str[s.size()], typename S::value_type()));
29     }
30     else
31         assert(T::eq(str[0], typename S::value_type()));
32 }
33 
34 TEST_CONSTEXPR_CXX20 bool test() {
35   {
36     typedef std::string S;
37     test(S(""));
38     test(S("abcde"));
39     test(S("abcdefghij"));
40     test(S("abcdefghijklmnopqrst"));
41   }
42 #if TEST_STD_VER >= 11
43   {
44     typedef std::basic_string<char, std::char_traits<char>, min_allocator<char>> S;
45     test(S(""));
46     test(S("abcde"));
47     test(S("abcdefghij"));
48     test(S("abcdefghijklmnopqrst"));
49   }
50 #endif
51 
52   return true;
53 }
54 
55 int main(int, char**)
56 {
57   test();
58 #if TEST_STD_VER > 17
59   static_assert(test());
60 #endif
61 
62   return 0;
63 }
64