libcxx/test/std/strings/string.view/string.view.iterators/rbegin.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_view>
  10
  11 // const_iterator rbegin() const;
  12
  13 #include <string_view>
  14 #include <cassert>
  15
  16 #include "test_macros.h"
  17
  18 template <class S>
  19 void
  20 test(S s)
  21 {
  22     const S& cs = s;
  23     typename S::reverse_iterator b = s.rbegin();
  24     typename S::const_reverse_iterator cb1 = cs.rbegin();
  25     typename S::const_reverse_iterator cb2 = s.crbegin();
  26     if (!s.empty())
  27     {
  28         const size_t last = s.size() - 1;
  29         assert(   *b ==  s[last]);
  30         assert(  &*b == &s[last]);
  31         assert( *cb1 ==  s[last]);
  32         assert(&*cb1 == &s[last]);
  33         assert( *cb2 ==  s[last]);
  34         assert(&*cb2 == &s[last]);
  35
  36     }
  37     assert(  b == cb1);
  38     assert(  b == cb2);
  39     assert(cb1 == cb2);
  40 }
  41
  42
  43 int main(int, char**)
  44 {
  45     typedef std::string_view    string_view;
  46 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
  47     typedef std::u8string_view  u8string_view;
  48 #endif
  49     typedef std::u16string_view u16string_view;
  50     typedef std::u32string_view u32string_view;
  51     typedef std::wstring_view   wstring_view;
  52
  53     test(string_view   ());
  54     test(u16string_view());
  55     test(u32string_view());
  56     test(wstring_view  ());
  57     test(string_view   ( "123"));
  58     test(wstring_view  (L"123"));
  59 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
  60     test(u8string_view{u8"123"});
  61 #endif
  62 #if TEST_STD_VER >= 11
  63     test(u16string_view{u"123"});
  64     test(u32string_view{U"123"});
  65 #endif
  66
  67 #if TEST_STD_VER > 14
  68     {
  69     constexpr string_view       sv { "123", 3 };
  70 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
  71     constexpr u8string_view u8sv  {u8"123", 3 };
  72 #endif
  73     constexpr u16string_view u16sv {u"123", 3 };
  74     constexpr u32string_view u32sv {U"123", 3 };
  75     constexpr wstring_view     wsv {L"123", 3 };
  76
  77     static_assert (    *sv.rbegin() ==    sv[2], "" );
  78 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
  79     static_assert (  *u8sv.rbegin() ==  u8sv[2], "" );
  80 #endif
  81     static_assert ( *u16sv.rbegin() == u16sv[2], "" );
  82     static_assert ( *u32sv.rbegin() == u32sv[2], "" );
  83     static_assert (   *wsv.rbegin() ==   wsv[2], "" );
  84
  85     static_assert (    *sv.crbegin() ==    sv[2], "" );
  86 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
  87     static_assert (  *u8sv.crbegin() == u8sv[2], "" );
  88 #endif
  89     static_assert ( *u16sv.crbegin() == u16sv[2], "" );
  90     static_assert ( *u32sv.crbegin() == u32sv[2], "" );
  91     static_assert (   *wsv.crbegin() ==   wsv[2], "" );
  92     }
  93 #endif
  94
  95   return 0;
  96 }