libstdc++-v3/testsuite/23_containers/unordered_multimap/insert/52476.cc

   1 // { dg-do run { target c++11 } }
   2 //
   3 // Copyright (C) 2012-2025 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10 //
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15 //
  16 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING3.  If not see
  18 // <http://www.gnu.org/licenses/>.
  19
  20 #include <unordered_map>
  21 #include <vector>
  22 #include <algorithm>
  23 #include <testsuite_hooks.h>
  24
  25 void test01()
  26 {
  27   using namespace std;
  28
  29   unordered_multimap<int, int> mmap;
  30   vector<int> values;
  31
  32   size_t nb_bkts = mmap.bucket_count();
  33   int i = 0;
  34   for (;; ++i)
  35     {
  36       mmap.insert(make_pair(0, i));
  37       if (mmap.bucket_count() != nb_bkts)
  38         // Container got rehash
  39         break;
  40       values.clear();
  41       transform(mmap.begin(), mmap.end(), back_inserter(values),
  42                 [](const pair<int, int>& p) { return p.second; });
  43     }
  44
  45   vector<int> rehash_values;
  46   transform(mmap.begin(), mmap.end(), back_inserter(rehash_values),
  47             [](const pair<int, int>& p) { return p.second; });
  48   // Remove the value that result in a rehash
  49   rehash_values.erase(remove(rehash_values.begin(), rehash_values.end(), i));
  50
  51   VERIFY( rehash_values == values );
  52 }
  53
  54 int main()
  55 {
  56   test01();
  57   return 0;
  58 }