xref: /llvm-project/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_front.pass.cpp (revision 31cbe0f240f660f15602c96b787c58a26f17e179)
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
10 
11 // <list>
12 
13 // template <class... Args> reference emplace_front(Args&&... args);
14 // return type is 'reference' in C++17; 'void' before
15 
16 #include <list>
17 #include <cassert>
18 
19 #include "test_macros.h"
20 #include "min_allocator.h"
21 
22 class A
23 {
24     int i_;
25     double d_;
26 
27     A(const A&);
28     A& operator=(const A&);
29 public:
A(int i,double d)30     A(int i, double d)
31         : i_(i), d_(d) {}
32 
geti() const33     int geti() const {return i_;}
getd() const34     double getd() const {return d_;}
35 };
36 
main(int,char **)37 int main(int, char**)
38 {
39     {
40     std::list<A> c;
41 #if TEST_STD_VER > 14
42     A& r1 = c.emplace_front(2, 3.5);
43     assert(c.size() == 1);
44     assert(&r1 == &c.front());
45     assert(c.front().geti() == 2);
46     assert(c.front().getd() == 3.5);
47     A& r2 = c.emplace_front(3, 4.5);
48     assert(c.size() == 2);
49     assert(&r2 == &c.front());
50 #else
51     c.emplace_front(2, 3.5);
52     assert(c.size() == 1);
53     assert(c.front().geti() == 2);
54     assert(c.front().getd() == 3.5);
55     c.emplace_front(3, 4.5);
56     assert(c.size() == 2);
57 #endif
58     assert(c.front().geti() == 3);
59     assert(c.front().getd() == 4.5);
60     assert(c.back().geti() == 2);
61     assert(c.back().getd() == 3.5);
62     }
63 
64     {
65     std::list<A, min_allocator<A>> c;
66 #if TEST_STD_VER > 14
67     A& r1 = c.emplace_front(2, 3.5);
68     assert(c.size() == 1);
69     assert(&r1 == &c.front());
70     assert(c.front().geti() == 2);
71     assert(c.front().getd() == 3.5);
72     A& r2 = c.emplace_front(3, 4.5);
73     assert(c.size() == 2);
74     assert(&r2 == &c.front());
75 #else
76     c.emplace_front(2, 3.5);
77     assert(c.size() == 1);
78     assert(c.front().geti() == 2);
79     assert(c.front().getd() == 3.5);
80     c.emplace_front(3, 4.5);
81     assert(c.size() == 2);
82 #endif
83     assert(c.front().geti() == 3);
84     assert(c.front().getd() == 4.5);
85     assert(c.back().geti() == 2);
86     assert(c.back().getd() == 3.5);
87     }
88 
89   return 0;
90 }
91