libstdc++-v3/testsuite/23_containers/unordered_set/operations/1.cc

   1 // Copyright (C) 2021-2023 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++20" }
  19 // { dg-do run { target c++20 } }
  20
  21 #include <unordered_set>
  22
  23 #ifndef __cpp_lib_generic_unordered_lookup
  24 # error "Feature-test macro for generic lookup missing in <unordered_set>"
  25 #elif __cpp_lib_generic_unordered_lookup < 201811L
  26 # error "Feature-test macro for generic lookup has wrong value in <unordered_set>"
  27 #endif
  28
  29 #include <testsuite_hooks.h>
  30
  31 struct Equal
  32 {
  33   typedef void is_transparent;
  34
  35   bool operator()(int i, long l) const { return i == l; }
  36   bool operator()(long l, int i) const { return l == i; }
  37   bool operator()(int i, int j) const { ++count; return i == j; }
  38
  39   static int count;
  40 };
  41
  42 int Equal::count = 0;
  43
  44 struct Hash
  45 {
  46   typedef void is_transparent;
  47
  48   std::size_t operator()(int i) const { ++count; return i; }
  49   std::size_t operator()(long l) const { return l; }
  50
  51   static int count;
  52 };
  53
  54 int Hash::count = 0;
  55
  56 using test_type = std::unordered_set<int, Hash, Equal>;
  57
  58 test_type x{ 1, 3, 5 };
  59 const test_type& cx = x;
  60
  61 void
  62 test01()
  63 {
  64   Hash::count = 0;
  65   Equal::count = 0;
  66
  67   VERIFY( x.contains(1L) );
  68
  69   auto it = x.find(1L);
  70   VERIFY( it != x.end() && *it == 1 );
  71   it = x.find(2L);
  72   VERIFY( it == x.end() );
  73
  74   auto cit = cx.find(3L);
  75   VERIFY( cit != cx.end() && *cit == 3 );
  76   cit = cx.find(2L);
  77   VERIFY( cit == cx.end() );
  78
  79   VERIFY( Hash::count == 0 );
  80   VERIFY( Equal::count == 0 );
  81
  82   static_assert(std::is_same<decltype(it), test_type::iterator>::value,
  83       "find returns iterator");
  84   static_assert(std::is_same<decltype(cit), test_type::const_iterator>::value,
  85       "const find returns const_iterator");
  86 }
  87
  88 void
  89 test02()
  90 {
  91   Hash::count = 0;
  92   Equal::count = 0;
  93
  94   auto n = x.count(1L);
  95   VERIFY( n == 1 );
  96   n = x.count(2L);
  97   VERIFY( n == 0 );
  98
  99   auto cn = cx.count(3L);
 100   VERIFY( cn == 1 );
 101   cn = cx.count(2L);
 102   VERIFY( cn == 0 );
 103
 104   VERIFY( Hash::count == 0 );
 105   VERIFY( Equal::count == 0 );
 106 }
 107
 108 void
 109 test03()
 110 {
 111   Hash::count = 0;
 112   Equal::count = 0;
 113
 114   auto it = x.equal_range(1L);
 115   VERIFY( it.first != it.second && *it.first == 1 );
 116   it = x.equal_range(2L);
 117   VERIFY( it.first == it.second && it.first == x.end() );
 118
 119   auto cit = cx.equal_range(1L);
 120   VERIFY( cit.first != cit.second && *cit.first == 1 );
 121   cit = cx.equal_range(2L);
 122   VERIFY( cit.first == cit.second && cit.first == cx.end() );
 123
 124   VERIFY( Hash::count == 0 );
 125   VERIFY( Equal::count == 0 );
 126
 127   using pair = std::pair<test_type::iterator, test_type::iterator>;
 128   static_assert(std::is_same<decltype(it), pair>::value,
 129       "equal_range returns pair<iterator, iterator>");
 130   using cpair = std::pair<test_type::const_iterator, test_type::const_iterator>;
 131   static_assert(std::is_same<decltype(cit), cpair>::value,
 132       "const equal_range returns pair<const_iterator, const_iterator>");
 133 }
 134
 135 void
 136 test04()
 137 {
 138   // https://gcc.gnu.org/ml/libstdc++/2015-01/msg00176.html
 139   // Verify the new function template overloads do not cause problems
 140   // when the comparison function is not transparent.
 141   struct I
 142   {
 143     int i;
 144     operator int() const { return i; }
 145   };
 146
 147   std::unordered_set<int> s;
 148   I i = { };
 149   s.find(i);
 150 }
 151
 152 void
 153 test05()
 154 {
 155   struct E
 156   {
 157     bool operator()(int l, int r) const { return l == r; }
 158
 159     struct Partition { };
 160
 161     bool operator()(int l, Partition) const { return l < 6; }
 162     bool operator()(Partition, int r) const { return r > 3; }
 163
 164     using is_transparent = void;
 165   };
 166
 167   struct H
 168   {
 169     size_t
 170     operator()(int x) const
 171     { return (size_t)(x / 10); }
 172
 173     size_t
 174     operator()(E::Partition) const
 175     { return 0; }
 176
 177     using is_transparent = void;
 178   };
 179
 180   std::unordered_set<int, H, E> s{ 1, 2, 3, 4, 5 };
 181
 182   auto n = s.count(E::Partition{});
 183   VERIFY( n == 2 );
 184 }
 185
 186 int
 187 main()
 188 {
 189   test01();
 190   test02();
 191   test03();
 192   test04();
 193   test05();
 194 }