1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // <string_view> 11 12 // constexpr const_iterator rend() const; 13 14 #include <string_view> 15 #include <cassert> 16 #include <cstddef> 17 18 #include "test_macros.h" 19 20 template <class S> 21 void 22 test(S s) 23 { 24 const S& cs = s; 25 typename S::reverse_iterator e = s.rend(); 26 typename S::const_reverse_iterator ce1 = cs.rend(); 27 typename S::const_reverse_iterator ce2 = s.crend(); 28 29 if (s.empty()) 30 { 31 assert( e == s.rbegin()); 32 assert(ce1 == cs.rbegin()); 33 assert(ce2 == s.rbegin()); 34 } 35 else 36 { 37 assert( e != s.rbegin()); 38 assert(ce1 != cs.rbegin()); 39 assert(ce2 != s.rbegin()); 40 } 41 42 assert(static_cast<std::size_t>( e - s.rbegin()) == s.size()); 43 assert(static_cast<std::size_t>(ce1 - cs.rbegin()) == cs.size()); 44 assert(static_cast<std::size_t>(ce2 - s.crbegin()) == s.size()); 45 46 assert( e == ce1); 47 assert( e == ce2); 48 assert(ce1 == ce2); 49 } 50 51 52 int main() 53 { 54 typedef std::string_view string_view; 55 typedef std::u16string_view u16string_view; 56 typedef std::u32string_view u32string_view; 57 typedef std::wstring_view wstring_view; 58 59 test(string_view ()); 60 test(u16string_view()); 61 test(u32string_view()); 62 test(wstring_view ()); 63 test(string_view ( "123")); 64 test(wstring_view (L"123")); 65 #if TEST_STD_VER >= 11 66 test(u16string_view{u"123"}); 67 test(u32string_view{U"123"}); 68 #endif 69 70 #if TEST_STD_VER > 14 71 { 72 constexpr string_view sv { "123", 3 }; 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.rend() == sv[0], "" ); 78 static_assert ( *--u16sv.rend() == u16sv[0], "" ); 79 static_assert ( *--u32sv.rend() == u32sv[0], "" ); 80 static_assert ( *--wsv.rend() == wsv[0], "" ); 81 82 static_assert ( *--sv.crend() == sv[0], "" ); 83 static_assert ( *--u16sv.crend() == u16sv[0], "" ); 84 static_assert ( *--u32sv.crend() == u32sv[0], "" ); 85 static_assert ( *--wsv.crend() == wsv[0], "" ); 86 } 87 #endif 88 } 89