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_base_of
12
13 #include <type_traits>
14
15 #include "test_macros.h"
16
17 template <class T, class U>
test_is_base_of()18 void test_is_base_of()
19 {
20 static_assert((std::is_base_of<T, U>::value), "");
21 static_assert((std::is_base_of<const T, U>::value), "");
22 static_assert((std::is_base_of<T, const U>::value), "");
23 static_assert((std::is_base_of<const T, const U>::value), "");
24 #if TEST_STD_VER > 14
25 static_assert((std::is_base_of_v<T, U>), "");
26 static_assert((std::is_base_of_v<const T, U>), "");
27 static_assert((std::is_base_of_v<T, const U>), "");
28 static_assert((std::is_base_of_v<const T, const U>), "");
29 #endif
30 }
31
32 template <class T, class U>
test_is_not_base_of()33 void test_is_not_base_of()
34 {
35 static_assert((!std::is_base_of<T, U>::value), "");
36 }
37
38 struct B {};
39 struct B1 : B {};
40 struct B2 : B {};
41 struct D : private B1, private B2 {};
42 struct I0; // incomplete
43
main(int,char **)44 int main(int, char**)
45 {
46 test_is_base_of<B, D>();
47 test_is_base_of<B1, D>();
48 test_is_base_of<B2, D>();
49 test_is_base_of<B, B1>();
50 test_is_base_of<B, B2>();
51 test_is_base_of<B, B>();
52
53 test_is_not_base_of<D, B>();
54 test_is_not_base_of<B&, D&>();
55 test_is_not_base_of<B[3], D[3]>();
56 test_is_not_base_of<int, int>();
57
58 // A scalar is never the base class of anything (including incomplete types)
59 test_is_not_base_of<int, B>();
60 test_is_not_base_of<int, B1>();
61 test_is_not_base_of<int, B2>();
62 test_is_not_base_of<int, D>();
63 test_is_not_base_of<int, I0>();
64
65 // A scalar never has base classes (including incomplete types)
66 test_is_not_base_of<B, int>();
67 test_is_not_base_of<B1, int>();
68 test_is_not_base_of<B2, int>();
69 test_is_not_base_of<D, int>();
70 test_is_not_base_of<I0, int>();
71
72 return 0;
73 }
74