libstdc++-v3/testsuite/25_algorithms/generate/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::input_iterator_wrapper;
  27 using __gnu_test::output_iterator_wrapper;
  28 using __gnu_test::forward_iterator_wrapper;
  29
  30 namespace ranges = std::ranges;
  31
  32 void
  33 test01()
  34 {
  35   const int c[6] = { 1, 2, 3, 4, 5, 6 };
  36
  37     {
  38       int x[6];
  39       int a = 1;
  40       VERIFY( ranges::generate(x, [&] { return a++; }) == x+6 );
  41       VERIFY( ranges::equal(x, c) );
  42     }
  43
  44     {
  45       int x[6];
  46       int a = 1;
  47       test_container<int, forward_iterator_wrapper> cx(x);
  48       VERIFY( ranges::generate(cx, [&] { return a++; }) == cx.end() );
  49       VERIFY( ranges::equal(cx, c) );
  50     }
  51
  52     {
  53       int x[6];
  54       int a = 1;
  55       test_range<int, output_iterator_wrapper> rx(x);
  56       VERIFY( ranges::generate(rx, [&] { return a++; }) == rx.end() );
  57       VERIFY( ranges::equal(x, c) );
  58     }
  59 }
  60
  61 constexpr bool
  62 test02()
  63 {
  64   const int c[6] = { 1, 2, 3, 4, 5, 6 };
  65   int x[6];
  66   int a = 1;
  67   ranges::generate(x, [&] { return a++; });
  68   return ranges::equal(x, c);
  69 }
  70
  71 int
  72 main()
  73 {
  74   test01();
  75   static_assert(test02());
  76 }