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: c++03, c++11, c++14, c++17
10
11// <string_view>
12
13// template<class charT, class traits>
14// constexpr auto operator<=>(basic_string_view<charT, traits> lhs, basic_string_view<charT, traits> rhs);
15//
16// LWG 3432
17// [string.view]/4
18// Mandates: R denotes a comparison category type ([cmp.categories]).
19
20#include <string_view>
21
22#include "test_macros.h"
23
24template <class CharT, class Ordering>
25struct traits {
26 typedef CharT char_type;
27 typedef int int_type;
28 typedef std::streamoff off_type;
29 typedef std::streampos pos_type;
30 typedef std::mbstate_t state_type;
31 using comparison_category = Ordering;
32
33 static constexpr void assign(char_type&, const char_type&) noexcept;
34 static constexpr bool eq(char_type&, const char_type&) noexcept;
35 static constexpr bool lt(char_type&, const char_type&) noexcept;
36
37 static constexpr int compare(const char_type*, const char_type*, std::size_t) { return 0; }
38 static constexpr std::size_t length(const char_type*);
39 static constexpr const char_type* find(const char_type*, std::size_t, const char_type&);
40 static constexpr char_type* move(char_type*, const char_type*, std::size_t);
41 static constexpr char_type* copy(char_type*, const char_type*, std::size_t);
42 static constexpr char_type* assign(char_type*, std::size_t, char_type);
43
44 static constexpr int_type not_eof(int_type) noexcept;
45
46 static constexpr char_type to_char_type(int_type) noexcept;
47
48 static constexpr int_type to_int_type(char_type) noexcept;
49
50 static constexpr bool eq_int_type(int_type, int_type) noexcept;
51
52 static constexpr int_type eof() noexcept;
53};
54
55template <class CharT, class Ordering, bool Valid>
56void test() {
57 using type = std::basic_string_view<CharT, traits<CharT, Ordering>>;
58 if constexpr (Valid)
59 type{} <=> type{};
60 else
61#ifndef TEST_HAS_NO_WIDE_CHARACTERS
62 // These diagnostics are issued for
63 // - Every invalid ordering
64 // - Every type
65 // expected-error-re@string_view:* 15 {{static assertion failed{{.*}}return type is not a comparison category type}}
66
67 // This diagnostic is not issued for Ordering == void.
68 // expected-error@string_view:* 10 {{no matching conversion for static_cast from}}
69#else
70 // One less test run when wchar_t is unavailable.
71 // expected-error-re@string_view:* 12 {{static assertion failed{{.*}}return type is not a comparison category type}}
72 // expected-error@string_view:* 8 {{no matching conversion for static_cast from}}
73#endif
74 type{} <=> type{};
75}
76
77template <class CharT>
78void test_all_orders() {
79 test<CharT, std::strong_ordering, true>();
80 test<CharT, std::weak_ordering, true>();
81 test<CharT, std::partial_ordering, true>();
82
83 test<CharT, void, false>();
84 test<CharT, int, false>();
85 test<CharT, float, false>();
86}
87
88void test_all_types() {
89 test_all_orders<char>();
90#ifndef TEST_HAS_NO_WIDE_CHARACTERS
91 test_all_orders<wchar_t>();
92#endif
93 test_all_orders<char8_t>();
94 test_all_orders<char16_t>();
95 test_all_orders<char32_t>();
96}
97

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