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

   1 // Copyright (C) 2020-2025 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-do run { target c++20 } }
  19
  20 #include <algorithm>
  21 #include <testsuite_hooks.h>
  22 #include <testsuite_iterators.h>
  23
  24 using __gnu_test::test_container;
  25 using __gnu_test::test_range;
  26 using __gnu_test::forward_iterator_wrapper;
  27
  28 namespace ranges = std::ranges;
  29
  30 void
  31 test01()
  32 {
  33   for (int k = 1; k <= 7; k++)
  34     {
  35       int x[] = {1,2,3,4,5,6,7};
  36       test_container<int, forward_iterator_wrapper> cx(x);
  37       auto pred = [&] (int a) { return a <= k; };
  38       auto middle = ranges::partition_point(cx, pred);
  39       VERIFY( middle.ptr == x+k );
  40     }
  41
  42   for (int k = 1; k <= 8; k++)
  43     {
  44       int x[] = {1,2,3,4,5,6,7,8};
  45       test_range<int, forward_iterator_wrapper> rx(x);
  46       auto pred = [&] (int a) { return a > -k; };
  47       auto proj = [] (int a) { return -a; };
  48       auto middle = ranges::partition_point(rx, pred, proj);
  49       VERIFY( middle.ptr == x+k-1 );
  50     }
  51 }
  52
  53 constexpr bool
  54 test02()
  55 {
  56   int x[] = {1,2,3,4,5};
  57   return (ranges::partition_point(x, x+5, [] (int a) { return a < 6; }) == x+5
  58           && ranges::partition_point(x, x+5, [] (int a) { return a < 0; }) == x);
  59 }
  60
  61 int
  62 main()
  63 {
  64   test01();
  65   static_assert(test02());
  66 }