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 //       iterator end(); // constexpr since C++20
12 // const_iterator end() const; // constexpr since C++20
13 
14 #include <string>
15 #include <cassert>
16 #include <cstddef>
17 
18 #include "test_macros.h"
19 #include "min_allocator.h"
20 
21 template <class S>
22 TEST_CONSTEXPR_CXX20 void
test(S s)23 test(S s)
24 {
25     const S& cs = s;
26     typename S::iterator e = s.end();
27     typename S::const_iterator ce = cs.end();
28     if (s.empty())
29     {
30         assert(e == s.begin());
31         assert(ce == cs.begin());
32     }
33     assert(static_cast<std::size_t>(e - s.begin()) == s.size());
34     assert(static_cast<std::size_t>(ce - cs.begin()) == cs.size());
35 }
36 
test()37 TEST_CONSTEXPR_CXX20 bool test() {
38   {
39     typedef std::string S;
40     test(S());
41     test(S("123"));
42   }
43 #if TEST_STD_VER >= 11
44   {
45     typedef std::basic_string<char, std::char_traits<char>, min_allocator<char>> S;
46     test(S());
47     test(S("123"));
48   }
49 #endif
50 
51   return true;
52 }
53 
main(int,char **)54 int main(int, char**)
55 {
56   test();
57 #if TEST_STD_VER > 17
58   static_assert(test());
59 #endif
60 
61   return 0;
62 }
63