libstdc++-v3/testsuite/23_containers/unordered_set/modifiers/merge.cc

   1 // Copyright (C) 2016-2021 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 3, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING3.  If not see
  16 // <http://www.gnu.org/licenses/>.
  17
  18 // { dg-options "-std=gnu++17" }
  19 // { dg-do run { target c++17 } }
  20
  21 #include <unordered_set>
  22 #include <algorithm>
  23 #include <testsuite_hooks.h>
  24
  25 using test_type = std::unordered_set<int>;
  26
  27 struct hash {
  28   auto operator()(int i) const noexcept { return ~std::hash<int>()(i); }
  29 };
  30 struct equal : std::equal_to<> { };
  31
  32 template<typename C1, typename C2>
  33 bool equal_elements(const C1& c1, const C2& c2)
  34 {
  35   if (c2.size() != c1.size())
  36     return false;
  37   for (auto& i : c1)
  38     if (c2.count(i) != c1.count(i))
  39       return false;
  40   return true;
  41 }
  42
  43 void
  44 test01()
  45 {
  46   const test_type c0{ 1, 2, 3, };
  47   test_type c1 = c0, c2 = c0;
  48
  49   c1.merge(c2);
  50   VERIFY( c1 == c0 );
  51   VERIFY( c2 == c0 );
  52
  53   c1.clear();
  54   c1.merge(c2);
  55   VERIFY( c1 == c0 );
  56   VERIFY( c2.empty() );
  57
  58   c2.merge(std::move(c1));
  59   VERIFY( c1.empty() );
  60   VERIFY( c2 == c0 );
  61 }
  62
  63 void
  64 test02()
  65 {
  66   const test_type c0{ 1, 2, 3, };
  67   test_type c1 = c0;
  68   std::unordered_set<int, hash, equal> c2( c0.begin(), c0.end() );
  69
  70   c1.merge(c2);
  71   VERIFY( c1 == c0 );
  72   VERIFY( equal_elements(c2, c0) );
  73
  74   c1.clear();
  75   c1.merge(c2);
  76   VERIFY( c1 == c0 );
  77   VERIFY( c2.empty() );
  78
  79   c2.merge(c1);
  80   VERIFY( c1.empty() );
  81   VERIFY( equal_elements(c2, c0) );
  82
  83   c1.merge(std::move(c2));
  84   VERIFY( c2.empty() );
  85   VERIFY( c1 == c0 );
  86 }
  87
  88 void
  89 test03()
  90 {
  91   const test_type c0{ 1, 2, 3, };
  92   test_type c1 = c0;
  93   std::unordered_multiset<int, hash, equal> c2( c0.begin(), c0.end() );
  94   c1.merge(c2);
  95   VERIFY( c1 == c0 );
  96   VERIFY( equal_elements(c2, c0) );
  97
  98   c1.clear();
  99   c1.merge(c2);
 100   VERIFY( c1 == c0 );
 101   VERIFY( c2.empty() );
 102
 103   c2.merge(c1);
 104   VERIFY( c1.empty() );
 105   VERIFY( equal_elements(c2, c0) );
 106
 107   c1 = c0;
 108   c2.merge(c1);
 109   VERIFY( c1.empty() );
 110   VERIFY( c2.size() == (2 * c0.size()) );
 111   VERIFY( c2.count(1) == 2 );
 112   VERIFY( c2.count(2) == 2 );
 113   VERIFY( c2.count(3) == 2 );
 114
 115   c1.merge(c2);
 116   VERIFY( c1 == c0 );
 117   VERIFY( equal_elements(c2, c0) );
 118
 119   c1.merge(std::move(c2));
 120   VERIFY( c1 == c0 );
 121   VERIFY( equal_elements(c2, c0) );
 122
 123   c1.clear();
 124   c1.merge(std::move(c2));
 125   VERIFY( c1 == c0 );
 126   VERIFY( c2.empty() );
 127 }
 128
 129 int
 130 main()
 131 {
 132   test01();
 133   test02();
 134   test03();
 135 }