1 //===----------------------------------------------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 // UNSUPPORTED: c++98, c++03
11 
12 // <experimental/memory_resource>
13 
14 //-----------------------------------------------------------------------------
15 // TESTING memory_resource * get_default_resource() noexcept;
16 //         memory_resource * set_default_resource(memory_resource*) noexcept;
17 //
18 // Concerns:
19 //  A) 'get_default_resource()' returns a non-null memory_resource pointer.
20 //  B) 'get_default_resource()' returns the value set by the last call to
21 //     'set_default_resource(...)' and 'new_delete_resource()' if no call
22 //     to 'set_default_resource(...)' has occurred.
23 //  C) 'set_default_resource(...)' returns the previous value of the default
24 //     resource.
25 //  D) 'set_default_resource(T* p)' for a non-null 'p' sets the default resource
26 //     to be 'p'.
27 //  E) 'set_default_resource(null)' sets the default resource to
28 //     'new_delete_resource()'.
29 //  F) 'get_default_resource' and 'set_default_resource' are noexcept.
30 
31 
32 #include <experimental/memory_resource>
33 #include <cassert>
34 
35 #include "test_memory_resource.hpp"
36 
37 using namespace std::experimental::pmr;
38 
39 int main() {
40     TestResource R;
41     { // Test (A) and (B)
42         memory_resource* p = get_default_resource();
43         assert(p != nullptr);
44         assert(p == new_delete_resource());
45         assert(p == get_default_resource());
46     }
47     { // Test (C) and (D)
48         memory_resource *expect = &R;
49         memory_resource *old = set_default_resource(expect);
50         assert(old != nullptr);
51         assert(old == new_delete_resource());
52 
53         memory_resource *p = get_default_resource();
54         assert(p != nullptr);
55         assert(p == expect);
56         assert(p == get_default_resource());
57     }
58     { // Test (E)
59         memory_resource* old = set_default_resource(nullptr);
60         assert(old == &R);
61         memory_resource* p = get_default_resource();
62         assert(p != nullptr);
63         assert(p == new_delete_resource());
64         assert(p == get_default_resource());
65     }
66     { // Test (F)
67         static_assert(noexcept(get_default_resource()),
68                       "get_default_resource() must be noexcept");
69 
70         static_assert(noexcept(set_default_resource(nullptr)),
71                       "set_default_resource() must be noexcept");
72     }
73 }
74