libstdc++-v3/testsuite/23_containers/stack/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 <stack>
  22 #include <testsuite_hooks.h>
  23
  24 void
  25 test01()
  26 {
  27   std::stack<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::stack<int>> );
  38
  39   static_assert( std::three_way_comparable<std::stack<int>,
  40                                            std::strong_ordering> );
  41   static_assert( ! std::three_way_comparable<std::stack<float>,
  42                                              std::strong_ordering> );
  43   static_assert( ! std::three_way_comparable<std::stack<float>,
  44                                              std::weak_ordering> );
  45   static_assert( std::three_way_comparable<std::stack<float>,
  46                                            std::partial_ordering> );
  47
  48   struct E
  49   {
  50     bool operator==(E) { return true; }
  51   };
  52   static_assert( ! std::three_way_comparable<E> );
  53   static_assert( ! std::three_way_comparable<std::stack<E>> );
  54 }
  55
  56 int
  57 main()
  58 {
  59   test01();
  60 }