libstdc++-v3/testsuite/23_containers/unordered_set/modifiers/reserve.cc

   1 // { dg-do run { target c++11 } }
   2
   3 // Copyright (C) 2012-2020 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_set>
  21 #include <testsuite_hooks.h>
  22
  23 void test01()
  24 {
  25   const int N = 1000;
  26
  27   typedef std::unordered_set<int> Set;
  28   Set s;
  29   s.reserve(N);
  30
  31   std::size_t bkts = s.bucket_count();
  32   for (int i = 0; i != N; ++i)
  33     {
  34       s.insert(i);
  35       // As long as we insert less than the reserved number of elements we
  36       // shouldn't experiment any rehash.
  37       VERIFY( s.bucket_count() == bkts );
  38     }
  39 }
  40
  41 void test02()
  42 {
  43   const int N = 1000;
  44
  45   typedef std::unordered_set<int> Set;
  46   Set s;
  47   s.reserve(N);
  48   s.reserve(N);
  49
  50   std::size_t bkts = s.bucket_count();
  51   for (int i = 0; i != N; ++i)
  52     {
  53       s.insert(i);
  54       // As long as we insert less than the reserved number of elements we
  55       // shouldn't experiment any rehash.
  56       VERIFY( s.bucket_count() == bkts );
  57     }
  58 }
  59
  60 int main()
  61 {
  62   test01();
  63   test02();
  64   return 0;
  65 }