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 | // constexpr optional<T>& operator=(const optional<T>& rhs); |
13 | |
14 | #include <optional> |
15 | #include <type_traits> |
16 | #include <cassert> |
17 | |
18 | #include "test_macros.h" |
19 | #include "archetypes.h" |
20 | |
21 | using std::optional; |
22 | |
23 | struct X |
24 | { |
25 | static bool throw_now; |
26 | |
27 | X() = default; |
28 | X(const X&) |
29 | { |
30 | if (throw_now) |
31 | TEST_THROW(6); |
32 | } |
33 | X& operator=(X const&) = default; |
34 | }; |
35 | |
36 | bool X::throw_now = false; |
37 | |
38 | template <class Tp> |
39 | constexpr bool assign_empty(optional<Tp>&& lhs) { |
40 | const optional<Tp> rhs; |
41 | lhs = rhs; |
42 | return !lhs.has_value() && !rhs.has_value(); |
43 | } |
44 | |
45 | template <class Tp> |
46 | constexpr bool assign_value(optional<Tp>&& lhs) { |
47 | const optional<Tp> rhs(101); |
48 | lhs = rhs; |
49 | return lhs.has_value() && rhs.has_value() && *lhs == *rhs; |
50 | } |
51 | |
52 | int main(int, char**) |
53 | { |
54 | { |
55 | using O = optional<int>; |
56 | static_assert(assign_empty(lhs: O{42})); |
57 | static_assert(assign_value(lhs: O{42})); |
58 | assert(assign_empty(O{42})); |
59 | assert(assign_value(O{42})); |
60 | } |
61 | { |
62 | using O = optional<TrivialTestTypes::TestType>; |
63 | static_assert(assign_empty(O{42})); |
64 | static_assert(assign_value(O{42})); |
65 | assert(assign_empty(O{42})); |
66 | assert(assign_value(O{42})); |
67 | } |
68 | { |
69 | using O = optional<TestTypes::TestType>; |
70 | assert(assign_empty(O{42})); |
71 | assert(assign_value(O{42})); |
72 | } |
73 | { |
74 | using T = TestTypes::TestType; |
75 | T::reset(); |
76 | optional<T> opt(3); |
77 | const optional<T> opt2; |
78 | assert(T::alive == 1); |
79 | opt = opt2; |
80 | assert(T::alive == 0); |
81 | assert(!opt2.has_value()); |
82 | assert(!opt.has_value()); |
83 | } |
84 | #ifndef TEST_HAS_NO_EXCEPTIONS |
85 | { |
86 | optional<X> opt; |
87 | optional<X> opt2(X{}); |
88 | assert(static_cast<bool>(opt2) == true); |
89 | try |
90 | { |
91 | X::throw_now = true; |
92 | opt = opt2; |
93 | assert(false); |
94 | } |
95 | catch (int i) |
96 | { |
97 | assert(i == 6); |
98 | assert(static_cast<bool>(opt) == false); |
99 | } |
100 | } |
101 | #endif |
102 | |
103 | return 0; |
104 | } |
105 | |