libstdc++-v3/testsuite/23_containers/multiset/operators/cmp_c++20.cc

   1 // Copyright (C) 2020-2023 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++2a" }
  19 // { dg-do run { target c++2a } }
  20
  21 #include <set>
  22 #include <testsuite_hooks.h>
  23
  24 void
  25 test01()
  26 {
  27   std::multiset<int> c1{ 1, 2, 3 }, c2{ 1, 2, 3, 4 }, c3{ 1, 2, 4 };
  28   VERIFY( c1 == c1 );
  29   VERIFY( std::is_eq(c1 <=> c1) );
  30   VERIFY( c1 < c2 );
  31   VERIFY( std::is_lt(c1 <=> c2) );
  32   VERIFY( c1 < c3 );
  33   VERIFY( std::is_lt(c1 <=> c3) );
  34   VERIFY( c2 < c3 );
  35   VERIFY( std::is_lt(c2 <=> c3) );
  36
  37   static_assert( std::totally_ordered<std::multiset<int>> );
  38
  39   static_assert( std::three_way_comparable<std::multiset<int>,
  40                                            std::strong_ordering> );
  41   static_assert( ! std::three_way_comparable<std::multiset<float>,
  42                                              std::strong_ordering> );
  43   static_assert( ! std::three_way_comparable<std::multiset<float>,
  44                                              std::weak_ordering> );
  45   static_assert( std::three_way_comparable<std::multiset<float>,
  46                                            std::partial_ordering> );
  47
  48   struct E
  49   {
  50     bool operator==(E) { return true; }
  51   };
  52   struct Cmp
  53   {
  54     bool operator()(E, E) const { return false; }
  55   };
  56   static_assert( ! std::totally_ordered<std::multiset<E, Cmp>> );
  57   static_assert( ! std::three_way_comparable<E> );
  58   static_assert( ! std::three_way_comparable<std::multiset<E, Cmp>> );
  59 }
  60
  61 void
  62 test02()
  63 {
  64   struct W
  65   {
  66     int value = 0;
  67
  68     bool operator==(W rhs) const noexcept
  69     { return (value | 1) == (rhs.value | 1); }
  70
  71     std::weak_ordering
  72     operator<=>(W rhs) const noexcept
  73     { return (value | 1) <=> (rhs.value | 1); }
  74   };
  75
  76   static_assert( std::totally_ordered<std::multiset<W>> );
  77
  78   std::multiset<W> c1{ {1}, {2}, {3} }, c2{ {0}, {3}, {3} };
  79   static_assert( std::same_as<decltype(c1 <=> c1), std::weak_ordering> );
  80   VERIFY( c1 == c2 );
  81   VERIFY( std::is_eq(c1 <=> c2) );
  82 }
  83
  84 void
  85 test04()
  86 {
  87   struct L
  88   {
  89     int value = 0;
  90
  91     bool operator<(L rhs) const noexcept { return value < rhs.value; }
  92   };
  93
  94   static_assert( std::totally_ordered<std::multiset<L>> );
  95
  96   std::multiset<L> c{ {1}, {2}, {3} }, d{ {1}, {2}, {3}, {4} };
  97   static_assert( std::same_as<decltype(c <=> c), std::weak_ordering> );
  98   VERIFY( std::is_lt(c <=> d) );
  99 }
 100
 101 // Associative container iterators are not random access
 102 static_assert( ! std::totally_ordered<std::multiset<int>::iterator> );
 103 static_assert( ! std::three_way_comparable<std::multiset<int>::iterator> );
 104
 105 int
 106 main()
 107 {
 108   test01();
 109   test02();
 110   test04();
 111 }