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
10 
11 // <variant>
12 
13 // template <size_t I, class... Types>
14 //  constexpr add_pointer_t<variant_alternative_t<I, variant<Types...>>>
15 //   get_if(variant<Types...>* v) noexcept;
16 // template <size_t I, class... Types>
17 //  constexpr add_pointer_t<const variant_alternative_t<I, variant<Types...>>>
18 //   get_if(const variant<Types...>* v) noexcept;
19 
20 #include "test_macros.h"
21 #include "variant_test_helpers.h"
22 #include <cassert>
23 #include <memory>
24 #include <variant>
25 
test_const_get_if()26 void test_const_get_if() {
27   {
28     using V = std::variant<int>;
29     constexpr const V *v = nullptr;
30     static_assert(std::get_if<0>(v) == nullptr, "");
31   }
32   {
33     using V = std::variant<int, const long>;
34     constexpr V v(42);
35     ASSERT_NOEXCEPT(std::get_if<0>(&v));
36     ASSERT_SAME_TYPE(decltype(std::get_if<0>(&v)), const int *);
37     static_assert(*std::get_if<0>(&v) == 42, "");
38     static_assert(std::get_if<1>(&v) == nullptr, "");
39   }
40   {
41     using V = std::variant<int, const long>;
42     constexpr V v(42l);
43     ASSERT_SAME_TYPE(decltype(std::get_if<1>(&v)), const long *);
44     static_assert(*std::get_if<1>(&v) == 42, "");
45     static_assert(std::get_if<0>(&v) == nullptr, "");
46   }
47 // FIXME: Remove these once reference support is reinstated
48 #if !defined(TEST_VARIANT_HAS_NO_REFERENCES)
49   {
50     using V = std::variant<int &>;
51     int x = 42;
52     const V v(x);
53     ASSERT_SAME_TYPE(decltype(std::get_if<0>(&v)), int *);
54     assert(std::get_if<0>(&v) == &x);
55   }
56   {
57     using V = std::variant<int &&>;
58     int x = 42;
59     const V v(std::move(x));
60     ASSERT_SAME_TYPE(decltype(std::get_if<0>(&v)), int *);
61     assert(std::get_if<0>(&v) == &x);
62   }
63   {
64     using V = std::variant<const int &&>;
65     int x = 42;
66     const V v(std::move(x));
67     ASSERT_SAME_TYPE(decltype(std::get_if<0>(&v)), const int *);
68     assert(std::get_if<0>(&v) == &x);
69   }
70 #endif
71 }
72 
test_get_if()73 void test_get_if() {
74   {
75     using V = std::variant<int>;
76     V *v = nullptr;
77     assert(std::get_if<0>(v) == nullptr);
78   }
79   {
80     using V = std::variant<int, long>;
81     V v(42);
82     ASSERT_NOEXCEPT(std::get_if<0>(&v));
83     ASSERT_SAME_TYPE(decltype(std::get_if<0>(&v)), int *);
84     assert(*std::get_if<0>(&v) == 42);
85     assert(std::get_if<1>(&v) == nullptr);
86   }
87   {
88     using V = std::variant<int, const long>;
89     V v(42l);
90     ASSERT_SAME_TYPE(decltype(std::get_if<1>(&v)), const long *);
91     assert(*std::get_if<1>(&v) == 42);
92     assert(std::get_if<0>(&v) == nullptr);
93   }
94 // FIXME: Remove these once reference support is reinstated
95 #if !defined(TEST_VARIANT_HAS_NO_REFERENCES)
96   {
97     using V = std::variant<int &>;
98     int x = 42;
99     V v(x);
100     ASSERT_SAME_TYPE(decltype(std::get_if<0>(&v)), int *);
101     assert(std::get_if<0>(&v) == &x);
102   }
103   {
104     using V = std::variant<const int &>;
105     int x = 42;
106     V v(x);
107     ASSERT_SAME_TYPE(decltype(std::get_if<0>(&v)), const int *);
108     assert(std::get_if<0>(&v) == &x);
109   }
110   {
111     using V = std::variant<int &&>;
112     int x = 42;
113     V v(std::move(x));
114     ASSERT_SAME_TYPE(decltype(std::get_if<0>(&v)), int *);
115     assert(std::get_if<0>(&v) == &x);
116   }
117   {
118     using V = std::variant<const int &&>;
119     int x = 42;
120     V v(std::move(x));
121     ASSERT_SAME_TYPE(decltype(std::get_if<0>(&v)), const int *);
122     assert(std::get_if<0>(&v) == &x);
123   }
124 #endif
125 }
126 
main(int,char **)127 int main(int, char**) {
128   test_const_get_if();
129   test_get_if();
130 
131   return 0;
132 }
133