libcxx/test/std/strings/basic.string/string.iterators/crend.pass.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-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 // <string>
  10
  11 // const_reverse_iterator crend() 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 test(const S& s) {
  21   typename S::const_reverse_iterator ce = s.crend();
  22   assert(ce == s.rend());
  23 }
  24
  25 template <class S>
  26 TEST_CONSTEXPR_CXX20 void test_string() {
  27   test(S());
  28   test(S("123"));
  29 }
  30
  31 TEST_CONSTEXPR_CXX20 bool test() {
  32   test_string<std::string>();
  33 #if TEST_STD_VER >= 11
  34   test_string<std::basic_string<char, std::char_traits<char>, min_allocator<char> > >();
  35 #endif
  36
  37   return true;
  38 }
  39
  40 int main(int, char**) {
  41   test();
  42 #if TEST_STD_VER > 17
  43   static_assert(test());
  44 #endif
  45
  46   return 0;
  47 }