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 // constexpr const_iterator rend() const; 12 13 #include <string_view> 14 #include <cassert> 15 #include <cstddef> 16 17 #include "test_macros.h" 18 19 template <class S> 20 void 21 test(S s) 22 { 23 const S& cs = s; 24 typename S::reverse_iterator e = s.rend(); 25 typename S::const_reverse_iterator ce1 = cs.rend(); 26 typename S::const_reverse_iterator ce2 = s.crend(); 27 28 if (s.empty()) 29 { 30 assert( e == s.rbegin()); 31 assert(ce1 == cs.rbegin()); 32 assert(ce2 == s.rbegin()); 33 } 34 else 35 { 36 assert( e != s.rbegin()); 37 assert(ce1 != cs.rbegin()); 38 assert(ce2 != s.rbegin()); 39 } 40 41 assert(static_cast<std::size_t>( e - s.rbegin()) == s.size()); 42 assert(static_cast<std::size_t>(ce1 - cs.rbegin()) == cs.size()); 43 assert(static_cast<std::size_t>(ce2 - s.crbegin()) == s.size()); 44 45 assert( e == ce1); 46 assert( e == ce2); 47 assert(ce1 == ce2); 48 } 49 50 51 int main(int, char**) 52 { 53 typedef std::string_view string_view; 54 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L 55 typedef std::u8string_view u8string_view; 56 #endif 57 typedef std::u16string_view u16string_view; 58 typedef std::u32string_view u32string_view; 59 60 test(string_view ()); 61 test(u16string_view()); 62 test(u32string_view()); 63 test(string_view ( "123")); 64 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L 65 test(u8string_view{u8"123"}); 66 #endif 67 #if TEST_STD_VER >= 11 68 test(u16string_view{u"123"}); 69 test(u32string_view{U"123"}); 70 #endif 71 72 #ifndef TEST_HAS_NO_WIDE_CHARACTERS 73 typedef std::wstring_view wstring_view; 74 test(wstring_view ()); 75 test(wstring_view (L"123")); 76 #endif 77 78 #if TEST_STD_VER > 14 79 { 80 constexpr string_view sv { "123", 3 }; 81 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L 82 constexpr u8string_view u8sv {u8"123", 3 }; 83 #endif 84 constexpr u16string_view u16sv {u"123", 3 }; 85 constexpr u32string_view u32sv {U"123", 3 }; 86 87 static_assert ( *--sv.rend() == sv[0], "" ); 88 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L 89 static_assert ( *--u8sv.rend() == u8sv[0], "" ); 90 #endif 91 static_assert ( *--u16sv.rend() == u16sv[0], "" ); 92 static_assert ( *--u32sv.rend() == u32sv[0], "" ); 93 94 static_assert ( *--sv.crend() == sv[0], "" ); 95 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L 96 static_assert ( *--u8sv.crend() == u8sv[0], "" ); 97 #endif 98 static_assert ( *--u16sv.crend() == u16sv[0], "" ); 99 static_assert ( *--u32sv.crend() == u32sv[0], "" ); 100 101 #ifndef TEST_HAS_NO_WIDE_CHARACTERS 102 { 103 constexpr wstring_view wsv {L"123", 3 }; 104 static_assert ( *--wsv.rend() == wsv[0], "" ); 105 static_assert ( *--wsv.crend() == wsv[0], "" ); 106 } 107 #endif 108 } 109 #endif // TEST_STD_VER > 14 110 111 return 0; 112 } 113