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 // <memory>
10 
11 // unique_ptr
12 
13 // Test swap
14 
15 #include <memory>
16 #include <cassert>
17 
18 #include "test_macros.h"
19 #include "deleter_types.h"
20 
21 struct A
22 {
23     int state_;
24     static int count;
25     A() : state_(0) {++count;}
26     explicit A(int i) : state_(i) {++count;}
27     A(const A& a) : state_(a.state_) {++count;}
28     A& operator=(const A& a) {state_ = a.state_; return *this;}
29     ~A() {--count;}
30 
31     friend bool operator==(const A& x, const A& y)
32         {return x.state_ == y.state_;}
33 };
34 
35 int A::count = 0;
36 
37 template <class T>
38 struct NonSwappableDeleter {
39   explicit NonSwappableDeleter(int) {}
40   NonSwappableDeleter& operator=(NonSwappableDeleter const&) { return *this; }
41   void operator()(T*) const {}
42 private:
43   NonSwappableDeleter(NonSwappableDeleter const&);
44 
45 };
46 
47 int main(int, char**)
48 {
49     {
50     A* p1 = new A(1);
51     std::unique_ptr<A, Deleter<A> > s1(p1, Deleter<A>(1));
52     A* p2 = new A(2);
53     std::unique_ptr<A, Deleter<A> > s2(p2, Deleter<A>(2));
54     assert(s1.get() == p1);
55     assert(*s1 == A(1));
56     assert(s1.get_deleter().state() == 1);
57     assert(s2.get() == p2);
58     assert(*s2 == A(2));
59     assert(s2.get_deleter().state() == 2);
60     swap(s1, s2);
61     assert(s1.get() == p2);
62     assert(*s1 == A(2));
63     assert(s1.get_deleter().state() == 2);
64     assert(s2.get() == p1);
65     assert(*s2 == A(1));
66     assert(s2.get_deleter().state() == 1);
67     assert(A::count == 2);
68     }
69     assert(A::count == 0);
70     {
71     A* p1 = new A[3];
72     std::unique_ptr<A[], Deleter<A[]> > s1(p1, Deleter<A[]>(1));
73     A* p2 = new A[3];
74     std::unique_ptr<A[], Deleter<A[]> > s2(p2, Deleter<A[]>(2));
75     assert(s1.get() == p1);
76     assert(s1.get_deleter().state() == 1);
77     assert(s2.get() == p2);
78     assert(s2.get_deleter().state() == 2);
79     swap(s1, s2);
80     assert(s1.get() == p2);
81     assert(s1.get_deleter().state() == 2);
82     assert(s2.get() == p1);
83     assert(s2.get_deleter().state() == 1);
84     assert(A::count == 6);
85     }
86     assert(A::count == 0);
87 #if TEST_STD_VER >= 11
88     {
89         // test that unique_ptr's specialized swap is disabled when the deleter
90         // is non-swappable. Instead we should pick up the generic swap(T, T)
91         // and perform 3 move constructions.
92         typedef NonSwappableDeleter<int> D;
93         D  d(42);
94         int x = 42;
95         int y = 43;
96         std::unique_ptr<int, D&> p(&x, d);
97         std::unique_ptr<int, D&> p2(&y, d);
98         std::swap(p, p2);
99     }
100 #endif
101 
102   return 0;
103 }
104