libstdc++-v3/testsuite/25_algorithms/copy_if/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 <vector>
  22 #include <testsuite_hooks.h>
  23 #include <testsuite_iterators.h>
  24
  25 using __gnu_test::test_container;
  26 using __gnu_test::test_range;
  27 using __gnu_test::input_iterator_wrapper;
  28 using __gnu_test::output_iterator_wrapper;
  29
  30 namespace ranges = std::ranges;
  31
  32 void
  33 test01()
  34 {
  35   int x[] = {1,2,3,4,5,6,7};
  36
  37     {
  38       const int y[] = {2,4,6};
  39       int w[7];
  40       test_range<int, input_iterator_wrapper> rx(x);
  41       test_range<int, output_iterator_wrapper> rw(w);
  42       auto [in,out] = ranges::copy_if(rx, rw.begin(),
  43                                       [] (int a) { return (a%2)==0; });
  44       VERIFY( in == rx.end() && out.ptr == w+3 );
  45       VERIFY( ranges::equal(w, w+3, y, y+3) );
  46     }
  47
  48     {
  49       const int y[] = {1,3,5,7};
  50       int w[7];
  51       test_range<int, input_iterator_wrapper> rx(x);
  52       test_range<int, output_iterator_wrapper> rw(w);
  53       auto [in,out] = ranges::copy_if(rx, rw.begin(),
  54                                       [] (int a) { return (a%2)==0; },
  55                                       [] (int a) { return a+1; });
  56       VERIFY( in == rx.end() && out.ptr == w+4 );
  57       VERIFY( ranges::equal(w, w+4, y, y+4) );
  58     }
  59 }
  60
  61 constexpr bool
  62 test02()
  63 {
  64   int x[] = {1,2,3};
  65   const int y[] = {1,3};
  66   int w[3];
  67   auto [in,out] = ranges::copy_if(x, w, [] (int a) { return (a%2)==1; });
  68   return ranges::equal(w, out, y, y+2);
  69 }
  70
  71 int
  72 main()
  73 {
  74   test01();
  75   static_assert(test02());
  76 }