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

   1 // Copyright (C) 2020-2021 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
  21 #include <algorithm>
  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::forward_iterator_wrapper;
  29
  30 namespace ranges = std::ranges;
  31
  32 struct X { int i; };
  33
  34 void
  35 test01()
  36 {
  37   X x[] = { {2}, {2}, {6}, {8}, {10}, {11}, {2} };
  38   auto res = ranges::count_if(x, x+7, [] (int i) { return i % 2 == 0; }, &X::i);
  39   VERIFY( res == 6 );
  40   res = ranges::count_if(x, x+7, [] (int i) { return i % 2 == 1; }, &X::i);
  41   VERIFY( res == 1 );
  42   res = ranges::count_if(x, x+7, [] (int i) { return i < 0; }, &X::i);
  43   VERIFY( res == 0 );
  44
  45   test_container<X, forward_iterator_wrapper> c(x);
  46   res = ranges::count_if(c, [] (int i) { return i == 2; }, &X::i);
  47   VERIFY( res == 3 );
  48   res = ranges::count_if(c, [] (int i) { return i < 0; }, &X::i);
  49   VERIFY( res == 0 );
  50
  51   test_range<X, input_iterator_wrapper> r(x);
  52   res = ranges::count_if(c, [] (int i) { return i == 2; }, &X::i);
  53   VERIFY( res == 3 );
  54   res = ranges::count_if(c, [] (int i) { return i < 0; }, &X::i);
  55   VERIFY( res == 0 );
  56 }
  57
  58 struct Y { int i; int j; };
  59
  60 void
  61 test02()
  62 {
  63   static constexpr Y y[] = { {1,2}, {2,4}, {3,6}, {1,6} };
  64   static_assert(ranges::count_if(y, [] (int i) { return i < 5; }, &Y::j) == 2);
  65   static_assert(ranges::count_if(y, [] (int i) { return i != 4; }, &Y::j) == 3);
  66 }
  67
  68 int
  69 main()
  70 {
  71   test01();
  72   test02();
  73 }