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 // <optional>
11 
12 // template <class U>
13 //   optional(const optional<U>& rhs);
14 
15 #include <optional>
16 #include <type_traits>
17 #include <cassert>
18 
19 #include "test_macros.h"
20 
21 using std::optional;
22 
23 template <class T, class U>
24 TEST_CONSTEXPR_CXX20 void
test(const optional<U> & rhs,bool is_going_to_throw=false)25 test(const optional<U>& rhs, bool is_going_to_throw = false)
26 {
27     bool rhs_engaged = static_cast<bool>(rhs);
28 #ifndef TEST_HAS_NO_EXCEPTIONS
29     try
30     {
31         optional<T> lhs = rhs;
32         assert(is_going_to_throw == false);
33         assert(static_cast<bool>(lhs) == rhs_engaged);
34         if (rhs_engaged)
35             assert(*lhs == *rhs);
36     }
37     catch (int i)
38     {
39         assert(i == 6);
40     }
41 #else
42     if (is_going_to_throw) return;
43     optional<T> lhs = rhs;
44     assert(static_cast<bool>(lhs) == rhs_engaged);
45     if (rhs_engaged)
46         assert(*lhs == *rhs);
47 #endif
48 }
49 
50 class X
51 {
52     int i_;
53 public:
X(int i)54     constexpr X(int i) : i_(i) {}
X(const X & x)55     constexpr X(const X& x) : i_(x.i_) {}
~X()56     TEST_CONSTEXPR_CXX20 ~X() {i_ = 0;}
operator ==(const X & x,const X & y)57     friend constexpr bool operator==(const X& x, const X& y) {return x.i_ == y.i_;}
58 };
59 
60 class Y
61 {
62     int i_;
63 public:
Y(int i)64     constexpr Y(int i) : i_(i) {}
65 
operator ==(const Y & x,const Y & y)66     friend constexpr bool operator==(const Y& x, const Y& y) {return x.i_ == y.i_;}
67 };
68 
69 int count = 0;
70 
71 class Z
72 {
73     int i_;
74 public:
Z(int i)75     Z(int i) : i_(i) {TEST_THROW(6);}
76 
operator ==(const Z & x,const Z & y)77     friend bool operator==(const Z& x, const Z& y) {return x.i_ == y.i_;}
78 };
79 
80 template<class T, class U>
test_all()81 constexpr bool test_all()
82 {
83   {
84     optional<U> rhs;
85     test<T>(rhs);
86   }
87   {
88     optional<U> rhs(U{3});
89     test<T>(rhs);
90   }
91   return true;
92 }
93 
main(int,char **)94 int main(int, char**)
95 {
96     test_all<int, short>();
97     test_all<X, int>();
98     test_all<Y, int>();
99 #if TEST_STD_VER > 17
100     static_assert(test_all<int, short>());
101     static_assert(test_all<X, int>());
102     static_assert(test_all<Y, int>());
103 #endif
104     {
105         typedef Z T;
106         typedef int U;
107         optional<U> rhs;
108         test<T>(rhs);
109     }
110     {
111         typedef Z T;
112         typedef int U;
113         optional<U> rhs(U{3});
114         test<T>(rhs, true);
115     }
116 
117     static_assert(!(std::is_constructible<optional<X>, const optional<Y>&>::value), "");
118 
119   return 0;
120 }
121