1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
|
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14
// <optional>
// From LWG2451:
// template<class U>
// optional<T>& operator=(const optional<U>& rhs);
#include <optional>
#include <type_traits>
#include <cassert>
#include "test_macros.h"
#include "archetypes.h"
using std::optional;
struct X
{
static bool throw_now;
X() = default;
X(int)
{
if (throw_now)
TEST_THROW(6);
}
};
bool X::throw_now = false;
struct Y1
{
Y1() = default;
Y1(const int&) {}
Y1& operator=(const Y1&) = delete;
};
struct Y2
{
Y2() = default;
Y2(const int&) = delete;
Y2& operator=(const int&) { return *this; }
};
template <class T>
struct AssignableFrom {
static int type_constructed;
static int type_assigned;
static int int_constructed;
static int int_assigned;
static void reset() {
type_constructed = int_constructed = 0;
type_assigned = int_assigned = 0;
}
AssignableFrom() = default;
explicit AssignableFrom(T) { ++type_constructed; }
AssignableFrom& operator=(T) { ++type_assigned; return *this; }
AssignableFrom(int) { ++int_constructed; }
AssignableFrom& operator=(int) { ++int_assigned; return *this; }
private:
AssignableFrom(AssignableFrom const&) = delete;
AssignableFrom& operator=(AssignableFrom const&) = delete;
};
template <class T> int AssignableFrom<T>::type_constructed = 0;
template <class T> int AssignableFrom<T>::type_assigned = 0;
template <class T> int AssignableFrom<T>::int_constructed = 0;
template <class T> int AssignableFrom<T>::int_assigned = 0;
void test_with_test_type() {
using T = TestTypes::TestType;
T::reset();
{ // non-empty to empty
T::reset_constructors();
optional<T> opt;
const optional<int> other(42);
opt = other;
assert(T::alive == 1);
assert(T::constructed == 1);
assert(T::value_constructed == 1);
assert(T::assigned == 0);
assert(T::destroyed == 0);
assert(static_cast<bool>(other) == true);
assert(*other == 42);
assert(static_cast<bool>(opt) == true);
assert(*opt == T(42));
}
assert(T::alive == 0);
{ // non-empty to non-empty
optional<T> opt(101);
const optional<int> other(42);
T::reset_constructors();
opt = other;
assert(T::alive == 1);
assert(T::constructed == 0);
assert(T::assigned == 1);
assert(T::value_assigned == 1);
assert(T::destroyed == 0);
assert(static_cast<bool>(other) == true);
assert(*other == 42);
assert(static_cast<bool>(opt) == true);
assert(*opt == T(42));
}
assert(T::alive == 0);
{ // empty to non-empty
optional<T> opt(101);
const optional<int> other;
T::reset_constructors();
opt = other;
assert(T::alive == 0);
assert(T::constructed == 0);
assert(T::assigned == 0);
assert(T::destroyed == 1);
assert(static_cast<bool>(other) == false);
assert(static_cast<bool>(opt) == false);
}
assert(T::alive == 0);
{ // empty to empty
optional<T> opt;
const optional<int> other;
T::reset_constructors();
opt = other;
assert(T::alive == 0);
assert(T::constructed == 0);
assert(T::assigned == 0);
assert(T::destroyed == 0);
assert(static_cast<bool>(other) == false);
assert(static_cast<bool>(opt) == false);
}
assert(T::alive == 0);
}
void test_ambiguous_assign() {
using OptInt = std::optional<int>;
{
using T = AssignableFrom<OptInt const&>;
const OptInt a(42);
T::reset();
{
std::optional<T> t;
t = a;
assert(T::type_constructed == 1);
assert(T::type_assigned == 0);
assert(T::int_constructed == 0);
assert(T::int_assigned == 0);
}
T::reset();
{
std::optional<T> t(42);
t = a;
assert(T::type_constructed == 0);
assert(T::type_assigned == 1);
assert(T::int_constructed == 1);
assert(T::int_assigned == 0);
}
T::reset();
{
std::optional<T> t(42);
t = std::move(a);
assert(T::type_constructed == 0);
assert(T::type_assigned == 1);
assert(T::int_constructed == 1);
assert(T::int_assigned == 0);
}
}
{
using T = AssignableFrom<OptInt&>;
OptInt a(42);
T::reset();
{
std::optional<T> t;
t = a;
assert(T::type_constructed == 1);
assert(T::type_assigned == 0);
assert(T::int_constructed == 0);
assert(T::int_assigned == 0);
}
{
using Opt = std::optional<T>;
static_assert(!std::is_assignable_v<Opt&, OptInt const&>, "");
}
}
}
int main(int, char**)
{
test_with_test_type();
test_ambiguous_assign();
{
optional<int> opt;
constexpr optional<short> opt2;
opt = opt2;
static_assert(static_cast<bool>(opt2) == false, "");
assert(static_cast<bool>(opt) == static_cast<bool>(opt2));
}
{
optional<int> opt;
constexpr optional<short> opt2(short{2});
opt = opt2;
static_assert(static_cast<bool>(opt2) == true, "");
static_assert(*opt2 == 2, "");
assert(static_cast<bool>(opt) == static_cast<bool>(opt2));
assert(*opt == *opt2);
}
{
optional<int> opt(3);
constexpr optional<short> opt2;
opt = opt2;
static_assert(static_cast<bool>(opt2) == false, "");
assert(static_cast<bool>(opt) == static_cast<bool>(opt2));
}
{
optional<int> opt(3);
constexpr optional<short> opt2(short{2});
opt = opt2;
static_assert(static_cast<bool>(opt2) == true, "");
static_assert(*opt2 == 2, "");
assert(static_cast<bool>(opt) == static_cast<bool>(opt2));
assert(*opt == *opt2);
}
#ifndef TEST_HAS_NO_EXCEPTIONS
{
optional<X> opt;
optional<int> opt2(42);
assert(static_cast<bool>(opt2) == true);
try
{
X::throw_now = true;
opt = opt2;
assert(false);
}
catch (int i)
{
assert(i == 6);
assert(static_cast<bool>(opt) == false);
}
}
#endif
return 0;
}
|
