libcxx/test/std/containers/unord/unord.multiset/erase_const_iter.pass.cpp

   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>
  26     TemplateConstructor (const T&) {}
  27 };
  28
  29 bool operator==(const TemplateConstructor&, const TemplateConstructor&) { return false; }
  30 struct Hash { std::size_t operator() (const TemplateConstructor &) const { return 0; } };
  31
  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 }