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 // UNSUPPORTED: !stdlib=libc++ && (c++03 || c++11 || c++14) 10 11 // <string_view> 12 13 // constexpr const_iterator rend() const; 14 15 #include <string_view> 16 #include <cassert> 17 #include <cstddef> 18 19 #include "test_macros.h" 20 21 template <class S> 22 void 23 test(S s) 24 { 25 const S& cs = s; 26 typename S::reverse_iterator e = s.rend(); 27 typename S::const_reverse_iterator ce1 = cs.rend(); 28 typename S::const_reverse_iterator ce2 = s.crend(); 29 30 if (s.empty()) 31 { 32 assert( e == s.rbegin()); 33 assert(ce1 == cs.rbegin()); 34 assert(ce2 == s.rbegin()); 35 } 36 else 37 { 38 assert( e != s.rbegin()); 39 assert(ce1 != cs.rbegin()); 40 assert(ce2 != s.rbegin()); 41 } 42 43 assert(static_cast<std::size_t>( e - s.rbegin()) == s.size()); 44 assert(static_cast<std::size_t>(ce1 - cs.rbegin()) == cs.size()); 45 assert(static_cast<std::size_t>(ce2 - s.crbegin()) == s.size()); 46 47 assert( e == ce1); 48 assert( e == ce2); 49 assert(ce1 == ce2); 50 } 51 52 53 int main(int, char**) 54 { 55 typedef std::string_view string_view; 56 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L 57 typedef std::u8string_view u8string_view; 58 #endif 59 typedef std::u16string_view u16string_view; 60 typedef std::u32string_view u32string_view; 61 62 test(string_view ()); 63 test(u16string_view()); 64 test(u32string_view()); 65 test(string_view ( "123")); 66 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L 67 test(u8string_view{u8"123"}); 68 #endif 69 #if TEST_STD_VER >= 11 70 test(u16string_view{u"123"}); 71 test(u32string_view{U"123"}); 72 #endif 73 74 #ifndef TEST_HAS_NO_WIDE_CHARACTERS 75 typedef std::wstring_view wstring_view; 76 test(wstring_view ()); 77 test(wstring_view (L"123")); 78 #endif 79 80 #if TEST_STD_VER > 14 81 { 82 constexpr string_view sv { "123", 3 }; 83 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L 84 constexpr u8string_view u8sv {u8"123", 3 }; 85 #endif 86 constexpr u16string_view u16sv {u"123", 3 }; 87 constexpr u32string_view u32sv {U"123", 3 }; 88 89 static_assert ( *--sv.rend() == sv[0], "" ); 90 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L 91 static_assert ( *--u8sv.rend() == u8sv[0], "" ); 92 #endif 93 static_assert ( *--u16sv.rend() == u16sv[0], "" ); 94 static_assert ( *--u32sv.rend() == u32sv[0], "" ); 95 96 static_assert ( *--sv.crend() == sv[0], "" ); 97 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L 98 static_assert ( *--u8sv.crend() == u8sv[0], "" ); 99 #endif 100 static_assert ( *--u16sv.crend() == u16sv[0], "" ); 101 static_assert ( *--u32sv.crend() == u32sv[0], "" ); 102 103 #ifndef TEST_HAS_NO_WIDE_CHARACTERS 104 { 105 constexpr wstring_view wsv {L"123", 3 }; 106 static_assert ( *--wsv.rend() == wsv[0], "" ); 107 static_assert ( *--wsv.crend() == wsv[0], "" ); 108 } 109 #endif 110 } 111 #endif // TEST_STD_VER > 14 112 113 return 0; 114 } 115