libstdc++-v3/testsuite/25_algorithms/stable_sort/constrained.cc

   1 // Copyright (C) 2020-2022 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 // { dg-require-cstdint "" }
  21
  22 #include <algorithm>
  23 #include <random>
  24 #include <vector>
  25 #include <testsuite_hooks.h>
  26 #include <testsuite_iterators.h>
  27
  28 using __gnu_test::test_container;
  29 using __gnu_test::test_range;
  30 using __gnu_test::random_access_iterator_wrapper;
  31
  32 namespace ranges = std::ranges;
  33
  34 // This test doesn't verify the stability property of ranges::stable_sort,
  35 // because at the moment it's just defined to be a wrapper over
  36 // std::stable_sort.
  37
  38 void
  39 test01()
  40 {
  41   for (unsigned size = 0; size < 50; ++size)
  42     {
  43       std::vector<int> vref(size);
  44       std::iota(vref.begin(), vref.end(), 0);
  45       std::vector<int> v1(vref), v2(vref);
  46       test_container<int, random_access_iterator_wrapper> c
  47         = {v1.data(), v1.data() + size};
  48       test_range<int, random_access_iterator_wrapper> r
  49         = {v2.data(), v2.data() + size};
  50
  51       std::ranlux48_base g1(size), g2(size + 1);
  52       ranges::shuffle(c, g1);
  53       ranges::shuffle(ranges::begin(r), ranges::end(r), g2);
  54
  55       auto res1 = ranges::stable_sort(c.begin(), c.end(), {}, std::negate<>{});
  56       VERIFY( res1 == c.end() );
  57
  58       auto res2 = ranges::stable_sort(r, ranges::greater{});
  59       VERIFY( res2 == ranges::end(r) );
  60
  61       VERIFY( ranges::equal(c, r) );
  62       VERIFY( ranges::equal(c.begin(), c.end(), vref.rbegin(), vref.rend()) );
  63     }
  64 }
  65
  66 int
  67 main()
  68 {
  69   test01();
  70 }