libstdc++-v3/testsuite/23_containers/unordered_map/allocator/minimal.cc

// Copyright (C) 2013-2023 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING3.  If not see
// <http://www.gnu.org/licenses/>.

// { dg-do run { target c++11 } }

#include <unordered_map>
#include <memory>
#include <testsuite_hooks.h>
#include <testsuite_allocator.h>

struct T { int i; };

struct hash
{
  std::size_t operator()(const T t) const noexcept
  { return t.i; }
};

struct equal_to
{
  bool operator()(const T& lhs, const T& rhs) const noexcept
  { return lhs.i == rhs.i; }
};


bool operator==(const T& l, const T& r) { return l.i == r.i; }
bool operator<(const T& l, const T& r) { return l.i < r.i; }

typedef __gnu_test::SimpleAllocator<std::pair<const T, T>> alloc_type;

template class std::unordered_map<T, T, hash, equal_to, alloc_type>;

void test01()
{
  typedef std::allocator_traits<alloc_type> traits_type;
  typedef std::unordered_map<T, T, hash, equal_to, alloc_type> test_type;
  test_type v(alloc_type{});
  v.emplace(std::piecewise_construct,
	    std::make_tuple(T()), std::make_tuple(T()));
  VERIFY( v.max_size() < traits_type::max_size(v.get_allocator()) );
}

int main()
{
  test01();
  return 0;
}