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// type_traits
10
11// is_convertible
12
13#include <type_traits>
14#include "test_macros.h"
15
16template <class T, class U>
17void test_is_convertible()
18{
19 static_assert((std::is_convertible<T, U>::value), "");
20 static_assert((std::is_convertible<const T, U>::value), "");
21 static_assert((std::is_convertible<T, const U>::value), "");
22 static_assert((std::is_convertible<const T, const U>::value), "");
23#if TEST_STD_VER > 14
24 static_assert((std::is_convertible_v<T, U>), "");
25 static_assert((std::is_convertible_v<const T, U>), "");
26 static_assert((std::is_convertible_v<T, const U>), "");
27 static_assert((std::is_convertible_v<const T, const U>), "");
28#endif
29}
30
31template <class T, class U>
32void test_is_not_convertible()
33{
34 static_assert((!std::is_convertible<T, U>::value), "");
35 static_assert((!std::is_convertible<const T, U>::value), "");
36 static_assert((!std::is_convertible<T, const U>::value), "");
37 static_assert((!std::is_convertible<const T, const U>::value), "");
38#if TEST_STD_VER > 14
39 static_assert((!std::is_convertible_v<T, U>), "");
40 static_assert((!std::is_convertible_v<const T, U>), "");
41 static_assert((!std::is_convertible_v<T, const U>), "");
42 static_assert((!std::is_convertible_v<const T, const U>), "");
43#endif
44}
45
46typedef void Function();
47typedef void ConstFunction() const;
48typedef char Array[1];
49
50struct StringType {
51 StringType(const char*) {}
52};
53
54class NonCopyable {
55 NonCopyable(NonCopyable&);
56};
57
58template <typename T>
59class CannotInstantiate {
60 enum { X = T::ThisExpressionWillBlowUp };
61};
62
63struct abstract { virtual int f() = 0; };
64
65int main(int, char**)
66{
67 // void
68 test_is_convertible<void,void> ();
69 test_is_not_convertible<void,Function> ();
70 test_is_not_convertible<void,Function&> ();
71 test_is_not_convertible<void,Function*> ();
72 test_is_not_convertible<void,Array> ();
73 test_is_not_convertible<void,Array&> ();
74 test_is_not_convertible<void,char> ();
75 test_is_not_convertible<void,char&> ();
76 test_is_not_convertible<void,char*> ();
77 test_is_not_convertible<char, void>();
78
79 // Function
80 test_is_not_convertible<Function, void> ();
81 test_is_not_convertible<Function, Function> ();
82 test_is_convertible<Function, Function&> ();
83 test_is_convertible<Function, Function*> ();
84 test_is_convertible<Function, Function*const> ();
85
86 static_assert(( std::is_convertible<Function, Function&&>::value), "");
87
88 test_is_not_convertible<Function, Array> ();
89 test_is_not_convertible<Function, Array&> ();
90 test_is_not_convertible<Function, char> ();
91 test_is_not_convertible<Function, char&> ();
92 test_is_not_convertible<Function, char*> ();
93
94 // Function&
95 test_is_not_convertible<Function&, void> ();
96 test_is_not_convertible<Function&, Function> ();
97 test_is_convertible<Function&, Function&> ();
98
99 test_is_convertible<Function&, Function*> ();
100 test_is_not_convertible<Function&, Array> ();
101 test_is_not_convertible<Function&, Array&> ();
102 test_is_not_convertible<Function&, char> ();
103 test_is_not_convertible<Function&, char&> ();
104 test_is_not_convertible<Function&, char*> ();
105
106 // Function*
107 test_is_not_convertible<Function*, void> ();
108 test_is_not_convertible<Function*, Function> ();
109 test_is_not_convertible<Function*, Function&> ();
110 test_is_convertible<Function*, Function*> ();
111
112 test_is_not_convertible<Function*, Array> ();
113 test_is_not_convertible<Function*, Array&> ();
114 test_is_not_convertible<Function*, char> ();
115 test_is_not_convertible<Function*, char&> ();
116 test_is_not_convertible<Function*, char*> ();
117
118 // Non-referencable function type
119 static_assert((!std::is_convertible<ConstFunction, Function>::value), "");
120// TODO(LLVM-19): Re-enable this once we switch to GCC 14. This is https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109680
121#ifndef TEST_COMPILER_GCC
122 static_assert((!std::is_convertible<ConstFunction, Function*>::value), "");
123 static_assert((!std::is_convertible<ConstFunction, Function&>::value), "");
124 static_assert((!std::is_convertible<ConstFunction, Function&&>::value), "");
125#endif
126 static_assert((!std::is_convertible<Function*, ConstFunction>::value), "");
127 static_assert((!std::is_convertible<Function&, ConstFunction>::value), "");
128 static_assert((!std::is_convertible<ConstFunction, ConstFunction>::value), "");
129 static_assert((!std::is_convertible<ConstFunction, void>::value), "");
130
131 // Array
132 test_is_not_convertible<Array, void> ();
133 test_is_not_convertible<Array, Function> ();
134 test_is_not_convertible<Array, Function&> ();
135 test_is_not_convertible<Array, Function*> ();
136 test_is_not_convertible<Array, Array> ();
137
138 static_assert((!std::is_convertible<Array, Array&>::value), "");
139 static_assert(( std::is_convertible<Array, const Array&>::value), "");
140 static_assert((!std::is_convertible<Array, const volatile Array&>::value), "");
141
142 static_assert((!std::is_convertible<const Array, Array&>::value), "");
143 static_assert(( std::is_convertible<const Array, const Array&>::value), "");
144 static_assert((!std::is_convertible<Array, volatile Array&>::value), "");
145 static_assert((!std::is_convertible<Array, const volatile Array&>::value), "");
146
147 static_assert(( std::is_convertible<Array, Array&&>::value), "");
148 static_assert(( std::is_convertible<Array, const Array&&>::value), "");
149 static_assert(( std::is_convertible<Array, volatile Array&&>::value), "");
150 static_assert(( std::is_convertible<Array, const volatile Array&&>::value), "");
151 static_assert(( std::is_convertible<const Array, const Array&&>::value), "");
152 static_assert((!std::is_convertible<Array&, Array&&>::value), "");
153 static_assert((!std::is_convertible<Array&&, Array&>::value), "");
154
155 test_is_not_convertible<Array, char> ();
156 test_is_not_convertible<Array, char&> ();
157
158 static_assert(( std::is_convertible<Array, char*>::value), "");
159 static_assert(( std::is_convertible<Array, const char*>::value), "");
160 static_assert(( std::is_convertible<Array, char* const>::value), "");
161 static_assert(( std::is_convertible<Array, char* const volatile>::value), "");
162
163 static_assert((!std::is_convertible<const Array, char*>::value), "");
164 static_assert(( std::is_convertible<const Array, const char*>::value), "");
165
166 static_assert((!std::is_convertible<char[42][42], char*>::value), "");
167 static_assert((!std::is_convertible<char[][1], char*>::value), "");
168
169 // Array&
170 test_is_not_convertible<Array&, void> ();
171 test_is_not_convertible<Array&, Function> ();
172 test_is_not_convertible<Array&, Function&> ();
173 test_is_not_convertible<Array&, Function*> ();
174 test_is_not_convertible<Array&, Array> ();
175
176 static_assert(( std::is_convertible<Array&, Array&>::value), "");
177 static_assert(( std::is_convertible<Array&, const Array&>::value), "");
178 static_assert((!std::is_convertible<const Array&, Array&>::value), "");
179 static_assert(( std::is_convertible<const Array&, const Array&>::value), "");
180
181 test_is_not_convertible<Array&, char> ();
182 test_is_not_convertible<Array&, char&> ();
183
184 static_assert(( std::is_convertible<Array&, char*>::value), "");
185 static_assert(( std::is_convertible<Array&, const char*>::value), "");
186 static_assert((!std::is_convertible<const Array&, char*>::value), "");
187 static_assert(( std::is_convertible<const Array&, const char*>::value), "");
188
189 static_assert((std::is_convertible<Array, StringType>::value), "");
190 static_assert((std::is_convertible<char(&)[], StringType>::value), "");
191
192 // char
193 test_is_not_convertible<char, void> ();
194 test_is_not_convertible<char, Function> ();
195 test_is_not_convertible<char, Function&> ();
196 test_is_not_convertible<char, Function*> ();
197 test_is_not_convertible<char, Array> ();
198 test_is_not_convertible<char, Array&> ();
199
200 test_is_convertible<char, char> ();
201
202 static_assert((!std::is_convertible<char, char&>::value), "");
203 static_assert(( std::is_convertible<char, const char&>::value), "");
204 static_assert((!std::is_convertible<const char, char&>::value), "");
205 static_assert(( std::is_convertible<const char, const char&>::value), "");
206
207 test_is_not_convertible<char, char*> ();
208
209 // char&
210 test_is_not_convertible<char&, void> ();
211 test_is_not_convertible<char&, Function> ();
212 test_is_not_convertible<char&, Function&> ();
213 test_is_not_convertible<char&, Function*> ();
214 test_is_not_convertible<char&, Array> ();
215 test_is_not_convertible<char&, Array&> ();
216
217 test_is_convertible<char&, char> ();
218
219 static_assert(( std::is_convertible<char&, char&>::value), "");
220 static_assert(( std::is_convertible<char&, const char&>::value), "");
221 static_assert((!std::is_convertible<const char&, char&>::value), "");
222 static_assert(( std::is_convertible<const char&, const char&>::value), "");
223
224 test_is_not_convertible<char&, char*> ();
225
226 // char*
227 test_is_not_convertible<char*, void> ();
228 test_is_not_convertible<char*, Function> ();
229 test_is_not_convertible<char*, Function&> ();
230 test_is_not_convertible<char*, Function*> ();
231 test_is_not_convertible<char*, Array> ();
232 test_is_not_convertible<char*, Array&> ();
233
234 test_is_not_convertible<char*, char> ();
235 test_is_not_convertible<char*, char&> ();
236
237 static_assert(( std::is_convertible<char*, char*>::value), "");
238 static_assert(( std::is_convertible<char*, const char*>::value), "");
239 static_assert((!std::is_convertible<const char*, char*>::value), "");
240 static_assert(( std::is_convertible<const char*, const char*>::value), "");
241
242 // NonCopyable
243 static_assert((std::is_convertible<NonCopyable&, NonCopyable&>::value), "");
244 static_assert((std::is_convertible<NonCopyable&, const NonCopyable&>::value), "");
245 static_assert((std::is_convertible<NonCopyable&, const volatile NonCopyable&>::value), "");
246 static_assert((std::is_convertible<NonCopyable&, volatile NonCopyable&>::value), "");
247 static_assert((std::is_convertible<const NonCopyable&, const NonCopyable&>::value), "");
248 static_assert((std::is_convertible<const NonCopyable&, const volatile NonCopyable&>::value), "");
249 static_assert((std::is_convertible<volatile NonCopyable&, const volatile NonCopyable&>::value), "");
250 static_assert((std::is_convertible<const volatile NonCopyable&, const volatile NonCopyable&>::value), "");
251 static_assert((!std::is_convertible<const NonCopyable&, NonCopyable&>::value), "");
252
253 // This test requires Access control SFINAE which we only have in C++11 or when
254 // we are using the compiler builtin for is_convertible.
255 test_is_not_convertible<NonCopyable&, NonCopyable>();
256
257
258 // Ensure that CannotInstantiate is not instantiated by is_convertible when it is not needed.
259 // For example CannotInstantiate is instantiated as a part of ADL lookup for arguments of type CannotInstantiate*.
260 static_assert((std::is_convertible<CannotInstantiate<int>*, CannotInstantiate<int>*>::value), "");
261
262 // Test for PR13592
263 static_assert(!std::is_convertible<abstract, abstract>::value, "");
264
265 return 0;
266}
267

source code of libcxx/test/std/utilities/meta/meta.rel/is_convertible.pass.cpp