1 //===----------------------------------------------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 // UNSUPPORTED: c++98, c++03, c++11, c++14
11 // <optional>
12 
13 // optional(optional<T>&& rhs);
14 
15 #include <optional>
16 #include <type_traits>
17 #include <cassert>
18 
19 #include "test_macros.h"
20 #include "archetypes.hpp"
21 
22 using std::optional;
23 
24 template <class T, class ...InitArgs>
25 void test(InitArgs&&... args)
26 {
27     const optional<T> orig(std::forward<InitArgs>(args)...);
28     optional<T> rhs(orig);
29     bool rhs_engaged = static_cast<bool>(rhs);
30     optional<T> lhs = std::move(rhs);
31     assert(static_cast<bool>(lhs) == rhs_engaged);
32     if (rhs_engaged)
33         assert(*lhs == *orig);
34 }
35 
36 void test_throwing_ctor() {
37 #ifndef TEST_HAS_NO_EXCEPTIONS
38     struct Z {
39       Z() : count(0) {}
40       Z(Z&& o) : count(o.count + 1)
41       { if (count == 2) throw 6; }
42       int count;
43     };
44     Z z;
45     optional<Z> rhs(std::move(z));
46     try
47     {
48         optional<Z> lhs(std::move(rhs));
49         assert(false);
50     }
51     catch (int i)
52     {
53         assert(i == 6);
54     }
55 #endif
56 }
57 
58 
59 template <class T, class ...InitArgs>
60 void test_ref(InitArgs&&... args)
61 {
62     optional<T> rhs(std::forward<InitArgs>(args)...);
63     bool rhs_engaged = static_cast<bool>(rhs);
64     optional<T> lhs = std::move(rhs);
65     assert(static_cast<bool>(lhs) == rhs_engaged);
66     if (rhs_engaged)
67         assert(&(*lhs) == &(*rhs));
68 }
69 
70 void test_reference_extension()
71 {
72 #if defined(_LIBCPP_VERSION) && 0 // FIXME these extensions are currently disabled.
73     using T = TestTypes::TestType;
74     T::reset();
75     {
76         T t;
77         T::reset_constructors();
78         test_ref<T&>();
79         test_ref<T&>(t);
80         assert(T::alive == 1);
81         assert(T::constructed == 0);
82         assert(T::assigned == 0);
83         assert(T::destroyed == 0);
84     }
85     assert(T::destroyed == 1);
86     assert(T::alive == 0);
87     {
88         T t;
89         const T& ct = t;
90         T::reset_constructors();
91         test_ref<T const&>();
92         test_ref<T const&>(t);
93         test_ref<T const&>(ct);
94         assert(T::alive == 1);
95         assert(T::constructed == 0);
96         assert(T::assigned == 0);
97         assert(T::destroyed == 0);
98     }
99     assert(T::alive == 0);
100     assert(T::destroyed == 1);
101     {
102         T t;
103         T::reset_constructors();
104         test_ref<T&&>();
105         test_ref<T&&>(std::move(t));
106         assert(T::alive == 1);
107         assert(T::constructed == 0);
108         assert(T::assigned == 0);
109         assert(T::destroyed == 0);
110     }
111     assert(T::alive == 0);
112     assert(T::destroyed == 1);
113     {
114         T t;
115         const T& ct = t;
116         T::reset_constructors();
117         test_ref<T const&&>();
118         test_ref<T const&&>(std::move(t));
119         test_ref<T const&&>(std::move(ct));
120         assert(T::alive == 1);
121         assert(T::constructed == 0);
122         assert(T::assigned == 0);
123         assert(T::destroyed == 0);
124     }
125     assert(T::alive == 0);
126     assert(T::destroyed == 1);
127     {
128         static_assert(!std::is_copy_constructible<std::optional<T&&>>::value, "");
129         static_assert(!std::is_copy_constructible<std::optional<T const&&>>::value, "");
130     }
131 #endif
132 }
133 
134 
135 int main()
136 {
137     test<int>();
138     test<int>(3);
139     {
140         using T = TestTypes::TestType;
141         T::reset();
142         optional<T> rhs;
143         assert(T::alive == 0);
144         const optional<T> lhs(std::move(rhs));
145         assert(lhs.has_value() == false);
146         assert(rhs.has_value() == false);
147         assert(T::alive == 0);
148     }
149     TestTypes::TestType::reset();
150     {
151         using T = TestTypes::TestType;
152         T::reset();
153         optional<T> rhs(42);
154         assert(T::alive == 1);
155         assert(T::value_constructed == 1);
156         assert(T::move_constructed == 0);
157         const optional<T> lhs(std::move(rhs));
158         assert(lhs.has_value());
159         assert(rhs.has_value());
160         assert(lhs.value().value == 42);
161         assert(rhs.value().value == -1);
162         assert(T::move_constructed == 1);
163         assert(T::alive == 2);
164     }
165     TestTypes::TestType::reset();
166     {
167         using namespace ConstexprTestTypes;
168         test<TestType>();
169         test<TestType>(42);
170     }
171     {
172         using namespace TrivialTestTypes;
173         test<TestType>();
174         test<TestType>(42);
175     }
176     {
177         test_throwing_ctor();
178     }
179     {
180         struct ThrowsMove {
181           ThrowsMove() noexcept(false) {}
182           ThrowsMove(ThrowsMove const&) noexcept(false) {}
183           ThrowsMove(ThrowsMove &&) noexcept(false) {}
184         };
185         static_assert(!std::is_nothrow_move_constructible<optional<ThrowsMove>>::value, "");
186         struct NoThrowMove {
187           NoThrowMove() noexcept(false) {}
188           NoThrowMove(NoThrowMove const&) noexcept(false) {}
189           NoThrowMove(NoThrowMove &&) noexcept(true) {}
190         };
191         static_assert(std::is_nothrow_move_constructible<optional<NoThrowMove>>::value, "");
192     }
193     {
194         test_reference_extension();
195     }
196 }
197