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 // template<class charT, class traits> 14 // constexpr bool operator==(basic_string_view<charT, traits> lhs, basic_string_view<charT, traits> rhs); 15 // (plus "sufficient additional overloads" to make implicit conversions work as intended) 16 17 #include <string_view> 18 #include <cassert> 19 #include <string> 20 21 #include "test_macros.h" 22 #include "constexpr_char_traits.h" 23 #include "make_string.h" 24 25 template<class T> 26 struct ConvertibleTo { 27 T t_; 28 TEST_CONSTEXPR explicit ConvertibleTo(T t) : t_(t) {} 29 TEST_CONSTEXPR operator T() const { 30 return t_; 31 } 32 }; 33 34 template<class SV> 35 TEST_CONSTEXPR_CXX14 bool test() 36 { 37 typedef typename SV::value_type CharT; 38 typedef typename SV::traits_type Traits; 39 40 // Test the behavior of the operator, both with and without implicit conversions. 41 SV v[] = { 42 SV(MAKE_CSTRING(CharT, "")), 43 SV(MAKE_CSTRING(CharT, "abc")), 44 SV(MAKE_CSTRING(CharT, "abcdef")), 45 SV(MAKE_CSTRING(CharT, "acb")), 46 }; 47 for (int i = 0; i < 4; ++i) { 48 for (int j = 0; j < 4; ++j) { 49 // See http://eel.is/c++draft/string.view#tab:string.view.comparison.overloads 50 bool expected = (i == j); 51 assert((v[i] == v[j]) == expected); 52 assert((v[i].data() == v[j]) == expected); 53 assert((v[i] == v[j].data()) == expected); 54 assert((ConvertibleTo<SV>(v[i]) == v[j]) == expected); 55 assert((v[i] == ConvertibleTo<SV>(v[j])) == expected); 56 57 if (!TEST_IS_CONSTANT_EVALUATED || TEST_STD_VER >= 20) { 58 assert((std::basic_string<CharT, Traits>(v[i]) == v[j]) == expected); 59 assert((v[i] == std::basic_string<CharT, Traits>(v[j])) == expected); 60 } 61 } 62 } 63 64 // Test its behavior with embedded null bytes. 65 SV abc = SV(MAKE_CSTRING(CharT, "abc")); 66 SV abc0def = SV(MAKE_CSTRING(CharT, "abc\0def"), 7); 67 SV abcdef = SV(MAKE_CSTRING(CharT, "abcdef")); 68 assert((abc == abc0def) == false); 69 assert((abc == abcdef) == false); 70 assert((abc0def == abc) == false); 71 assert((abc0def == abcdef) == false); 72 assert((abcdef == abc) == false); 73 assert((abcdef == abc0def) == false); 74 75 assert((abc.data() == abc0def) == false); 76 assert((abc0def == abc.data()) == false); 77 78 if (!TEST_IS_CONSTANT_EVALUATED || TEST_STD_VER >= 20) { 79 assert((std::basic_string<CharT, Traits>(abc) == abc0def) == false); 80 assert((abc0def == std::basic_string<CharT, Traits>(abc)) == false); 81 } 82 83 return true; 84 } 85 86 int main(int, char**) 87 { 88 test<std::string_view>(); 89 #ifndef TEST_HAS_NO_WIDE_CHARACTERS 90 test<std::wstring_view>(); 91 #endif 92 #if TEST_STD_VER >= 11 93 test<std::u16string_view>(); 94 test<std::u32string_view>(); 95 #endif 96 #if TEST_STD_VER > 14 97 static_assert(test<std::string_view>(), ""); 98 #ifndef TEST_HAS_NO_WIDE_CHARACTERS 99 static_assert(test<std::wstring_view>(), ""); 100 #endif 101 static_assert(test<std::u16string_view>(), ""); 102 static_assert(test<std::u32string_view>(), ""); 103 #endif 104 105 #if TEST_STD_VER > 11 106 test<std::basic_string_view<char, constexpr_char_traits<char>>>(); 107 static_assert(test<std::basic_string_view<char, constexpr_char_traits<char>>>(), ""); 108 #endif 109 110 #if TEST_STD_VER > 17 111 test<std::u8string_view>(); 112 static_assert(test<std::u8string_view>()); 113 #endif 114 115 return 0; 116 } 117