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
25template <class T>
26struct ConvertibleTo {
27 T t_;
28 TEST_CONSTEXPR explicit ConvertibleTo(T t) : t_(t) {}
29 TEST_CONSTEXPR operator T() const { return t_; }
30};
31
32template <class SV>
33TEST_CONSTEXPR_CXX14 bool test() {
34 typedef typename SV::value_type CharT;
35 typedef typename SV::traits_type Traits;
36
37 // Test the behavior of the operator, both with and without implicit conversions.
38 SV v[] = {
39 SV(MAKE_CSTRING(CharT, "")),
40 SV(MAKE_CSTRING(CharT, "abc")),
41 SV(MAKE_CSTRING(CharT, "abcdef")),
42 SV(MAKE_CSTRING(CharT, "acb")),
43 };
44 for (int i = 0; i < 4; ++i) {
45 for (int j = 0; j < 4; ++j) {
46 // See http://eel.is/c++draft/string.view#tab:string.view.comparison.overloads
47 bool expected = (i < j);
48 assert((v[i] < v[j]) == expected);
49 assert((v[i].data() < v[j]) == expected);
50 assert((v[i] < v[j].data()) == expected);
51 assert((ConvertibleTo<SV>(v[i]) < v[j]) == expected);
52 assert((v[i] < ConvertibleTo<SV>(v[j])) == expected);
53
54 if (TEST_STD_AT_LEAST_20_OR_RUNTIME_EVALUATED) {
55 assert((std::basic_string<CharT, Traits>(v[i]) < v[j]) == expected);
56 assert((v[i] < std::basic_string<CharT, Traits>(v[j])) == expected);
57 }
58 }
59 }
60
61 // Test its behavior with embedded null bytes.
62 SV abc = SV(MAKE_CSTRING(CharT, "abc"));
63 SV abc0def = SV(MAKE_CSTRING(CharT, "abc\0def"), 7);
64 SV abcdef = SV(MAKE_CSTRING(CharT, "abcdef"));
65 assert((abc < abc0def) == true);
66 assert((abc < abcdef) == true);
67 assert((abc0def < abc) == false);
68 assert((abc0def < abcdef) == true);
69 assert((abcdef < abc) == false);
70 assert((abcdef < abc0def) == false);
71
72 assert((abc.data() < abc0def) == true);
73 assert((abc0def < abc.data()) == false);
74
75 if (TEST_STD_AT_LEAST_20_OR_RUNTIME_EVALUATED) {
76 assert((std::basic_string<CharT, Traits>(abc) < abc0def) == true);
77 assert((abc0def < std::basic_string<CharT, Traits>(abc)) == false);
78 }
79
80 return true;
81}
82
83int main(int, char**) {
84 test<std::string_view>();
85#ifndef TEST_HAS_NO_WIDE_CHARACTERS
86 test<std::wstring_view>();
87#endif
88#if TEST_STD_VER >= 11
89 test<std::u16string_view>();
90 test<std::u32string_view>();
91#endif
92#if TEST_STD_VER > 14
93 static_assert(test<std::string_view>(), "");
94# ifndef TEST_HAS_NO_WIDE_CHARACTERS
95 static_assert(test<std::wstring_view>(), "");
96# endif
97 static_assert(test<std::u16string_view>(), "");
98 static_assert(test<std::u32string_view>(), "");
99#endif
100
101#if TEST_STD_VER > 11
102 test<std::basic_string_view<char, constexpr_char_traits<char>>>();
103 static_assert(test<std::basic_string_view<char, constexpr_char_traits<char>>>(), "");
104#endif
105
106#if TEST_STD_VER > 17
107 test<std::u8string_view>();
108 static_assert(test<std::u8string_view>());
109#endif
110
111 return 0;
112}
113

source code of libcxx/test/std/strings/string.view/string.view.comparison/less.pass.cpp