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_array
12
13#include <type_traits>
14#include <cstddef> // for std::nullptr_t
15#include "test_macros.h"
16
17template <class T>
18void test_is_array()
19{
20 static_assert( std::is_array<T>::value, "");
21 static_assert( std::is_array<const T>::value, "");
22 static_assert( std::is_array<volatile T>::value, "");
23 static_assert( std::is_array<const volatile T>::value, "");
24#if TEST_STD_VER > 14
25 static_assert( std::is_array_v<T>, "");
26 static_assert( std::is_array_v<const T>, "");
27 static_assert( std::is_array_v<volatile T>, "");
28 static_assert( std::is_array_v<const volatile T>, "");
29#endif
30}
31
32template <class T>
33void test_is_not_array()
34{
35 static_assert(!std::is_array<T>::value, "");
36 static_assert(!std::is_array<const T>::value, "");
37 static_assert(!std::is_array<volatile T>::value, "");
38 static_assert(!std::is_array<const volatile T>::value, "");
39#if TEST_STD_VER > 14
40 static_assert(!std::is_array_v<T>, "");
41 static_assert(!std::is_array_v<const T>, "");
42 static_assert(!std::is_array_v<volatile T>, "");
43 static_assert(!std::is_array_v<const volatile T>, "");
44#endif
45}
46
47class Empty
48{
49};
50
51class NotEmpty
52{
53 virtual ~NotEmpty();
54};
55
56union Union {};
57
58struct bit_zero
59{
60 int : 0;
61};
62
63class Abstract
64{
65 virtual ~Abstract() = 0;
66};
67
68enum Enum {zero, one};
69struct incomplete_type;
70
71typedef void (*FunctionPtr)();
72
73int main(int, char**)
74{
75 test_is_array<char[3]>();
76 // Android clang-r536225 identifies as clang-19.0, but it predates the
77 // LLVM 19.0.0 release. It lacks llvm.org/pr86652, which changed __is_array
78 // to return false for T[0]. llvm.org/pr93037 relies on that change for
79 // correct handling of std::is_array<T[0]>. This test will pass as long as
80 // Clang and libc++ come from the same LLVM commit, but we can't detect that
81 // here.
82#if !defined(__ANDROID__) || TEST_CLANG_VER != 1900
83 test_is_not_array<char[0]>();
84#endif
85 test_is_array<char[]>();
86 test_is_array<Union[]>();
87
88 test_is_not_array<std::nullptr_t>();
89 test_is_not_array<void>();
90 test_is_not_array<int&>();
91 test_is_not_array<int&&>();
92 test_is_not_array<int*>();
93 test_is_not_array<double>();
94 test_is_not_array<const int*>();
95 test_is_not_array<Enum>();
96 test_is_not_array<Union>();
97 test_is_not_array<FunctionPtr>();
98 test_is_not_array<Empty>();
99 test_is_not_array<bit_zero>();
100 test_is_not_array<NotEmpty>();
101 test_is_not_array<incomplete_type>(); // LWG#2582
102
103 return 0;
104}
105

source code of libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_array.pass.cpp