xref: /llvm-project/libcxx/test/std/containers/unord/unord.multiset/erase_const_iter.pass.cpp (revision fb855eb941b6d740cc6560297d0b4d3201dcaf9f)
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 // <unordered_set>
10 
11 // template <class Value, class Hash = hash<Value>, class Pred = equal_to<Value>,
12 //           class Alloc = allocator<Value>>
13 // class unordered_multiset
14 
15 // iterator erase(const_iterator p)
16 
17 #include <unordered_set>
18 #include <cassert>
19 
20 #include "test_macros.h"
21 #include "min_allocator.h"
22 
23 struct TemplateConstructor
24 {
25     template<typename T>
TemplateConstructorTemplateConstructor26     TemplateConstructor (const T&) {}
27 };
28 
operator ==(const TemplateConstructor &,const TemplateConstructor &)29 bool operator==(const TemplateConstructor&, const TemplateConstructor&) { return false; }
operator ()Hash30 struct Hash { std::size_t operator() (const TemplateConstructor &) const { return 0; } };
31 
main(int,char **)32 int main(int, char**)
33 {
34     {
35         typedef std::unordered_multiset<int> C;
36         typedef int P;
37         P a[] =
38         {
39             P(1),
40             P(2),
41             P(3),
42             P(4),
43             P(1),
44             P(2)
45         };
46         C c(a, a + sizeof(a)/sizeof(a[0]));
47         C::const_iterator i = c.find(2);
48         C::const_iterator i_next = i;
49         ++i_next;
50         C::iterator j = c.erase(i);
51         assert(j == i_next);
52 
53         assert(c.size() == 5);
54         assert(c.count(1) == 2);
55         assert(c.count(2) == 1);
56         assert(c.count(3) == 1);
57         assert(c.count(4) == 1);
58     }
59 #if TEST_STD_VER >= 11
60     {
61         typedef std::unordered_multiset<int, std::hash<int>,
62                                       std::equal_to<int>, min_allocator<int>> C;
63         typedef int P;
64         P a[] =
65         {
66             P(1),
67             P(2),
68             P(3),
69             P(4),
70             P(1),
71             P(2)
72         };
73         C c(a, a + sizeof(a)/sizeof(a[0]));
74         C::const_iterator i = c.find(2);
75         C::const_iterator i_next = i;
76         ++i_next;
77         C::iterator j = c.erase(i);
78         assert(j == i_next);
79         assert(c.size() == 5);
80         assert(c.count(1) == 2);
81         assert(c.count(2) == 1);
82         assert(c.count(3) == 1);
83         assert(c.count(4) == 1);
84     }
85 #endif
86 #if TEST_STD_VER >= 14
87     {
88     //  This is LWG #2059
89         typedef TemplateConstructor T;
90         typedef std::unordered_set<T, Hash> C;
91         typedef C::iterator I;
92 
93         C m;
94         T a{0};
95         I it = m.find(a);
96         if (it != m.end())
97             m.erase(it);
98     }
99 #endif
100 
101   return 0;
102 }
103