xref: /llvm-project/libcxx/test/std/strings/basic.string/string.iterators/crbegin.pass.cpp (revision 425620ccdd47e56b59512913cdc71e116f951e4e)
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 // XFAIL: LIBCXX-AIX-FIXME
10 
11 // <string>
12 
13 // const_reverse_iterator crbegin() const; // constexpr since C++20
14 
15 #include <string>
16 #include <cassert>
17 
18 #include "test_macros.h"
19 #include "min_allocator.h"
20 
21 template <class S>
22 TEST_CONSTEXPR_CXX20 void
23 test(const S& s)
24 {
25     typename S::const_reverse_iterator cb = s.crbegin();
26     if (!s.empty())
27     {
28         assert(*cb == s.back());
29     }
30     assert(cb == s.rbegin());
31 }
32 
33 TEST_CONSTEXPR_CXX20 bool test() {
34   {
35     typedef std::string S;
36     test(S());
37     test(S("123"));
38   }
39 #if TEST_STD_VER >= 11
40   {
41     typedef std::basic_string<char, std::char_traits<char>, min_allocator<char>> S;
42     test(S());
43     test(S("123"));
44   }
45 #endif
46 
47   return true;
48 }
49 
50 int main(int, char**)
51 {
52   test();
53 #if TEST_STD_VER > 17
54   static_assert(test());
55 #endif
56 
57   return 0;
58 }
59