(root)/
gcc-13.2.0/
libstdc++-v3/
testsuite/
23_containers/
vector/
modifiers/
emplace/
self_emplace.cc
// { dg-do run { target c++11 } }

// Copyright (C) 2016-2023 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/>.

#include <vector>
#include "testsuite_hooks.h"

void
test01()
{
  std::vector<std::vector<int>> vv =
    {
      { 2, 3 },
      { 4, 5 },
      { 0, 1 }
    };

  // Make sure emplace will imply reallocation.
  VERIFY( vv.capacity() == 3 );

  vv.emplace(vv.begin(), vv[0]);

  VERIFY( vv.size() == 4 );
  VERIFY( vv[0].size() == 2 );
  VERIFY( vv[0][0] == 2 );
  VERIFY( vv[0][1] == 3 );
}

void
test02()
{
  std::vector<std::vector<int>> vv =
    {
      { 2, 3 },
      { 4, 5 },
      { 0, 1 }
    };

  // Make sure emplace won't reallocate.
  vv.reserve(4);
  vv.emplace(vv.begin(), vv[0]);

  VERIFY( vv.size() == 4 );
  VERIFY( vv[0].size() == 2 );
  VERIFY( vv[0][0] == 2 );
  VERIFY( vv[0][1] == 3 );
}

struct A
{
  A(int i) : _i(i)
  { }

  A(const A& other) : _i(other._i)
  {
    VERIFY( other._i >= 0 );
  }

  A(A&& other) : _i(other._i)
  {
    VERIFY( other._i >= 0 );

    other._i = -1;
  }

  A(std::vector<A>::iterator it) : _i(it->_i)
  {
    VERIFY( it->_i >= 0 );
  }

  A& operator=(const A&) = default;
  A& operator=(A&& other)
  {
    VERIFY(other._i >= 0 );

    _i = other._i;
    other._i = -1;
    return *this;
  }

  int _i;
};

void
test03()
{
  std::vector<A> va =
    {
      { A(1) },
      { A(2) },
      { A(3) }
    };

  // Make sure emplace will imply reallocation.
  VERIFY( va.capacity() == 3 );

  va.emplace(va.begin(), va.begin());

  VERIFY( va.size() == 4 );
  VERIFY( va[0]._i == 1 );
}

void
test04()
{
  std::vector<A> va =
    {
      { A(1) },
      { A(2) },
      { A(3) }
    };

  // Make sure emplace won't reallocate.
  va.reserve(4);
  va.emplace(va.begin(), va.begin());

  VERIFY( va.size() == 4 );
  VERIFY( va[0]._i == 1 );
}

void
test05()
{
  // LWG DR 2164
  std::vector<int> v;
  v.reserve(4);
  v = { 1, 2, 3 };
  v.emplace(v.begin(), v.back());
  VERIFY( v[0] == 3 );
  VERIFY( v[1] == 1 );
  VERIFY( v[2] == 2 );
  VERIFY( v[3] == 3 );
}

int main()
{
  test01();
  test02();
  test03();
  test04();
}