libstdc++-v3/testsuite/std/ranges/adaptors/drop_while.cc

   1 // Copyright (C) 2020 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 <ranges>
  23 #include <testsuite_hooks.h>
  24 #include <testsuite_iterators.h>
  25
  26 using __gnu_test::test_range;
  27 using __gnu_test::bidirectional_iterator_wrapper;
  28
  29 namespace ranges = std::ranges;
  30 namespace views = std::ranges::views;
  31
  32 void
  33 test01()
  34 {
  35   auto p = [] (int i) { return i != 16; };
  36   auto v = views::iota(10) | views::drop_while(p);
  37   VERIFY( ranges::equal(v | views::take(5), (int[]){16,17,18,19,20}) );
  38   using R = decltype(v);
  39   static_assert(ranges::view<R>);
  40   static_assert(!ranges::common_range<R>);
  41   static_assert(ranges::random_access_range<R>);
  42 }
  43
  44 void
  45 test02()
  46 {
  47   int x[] = {1,2,3,4,5};
  48   test_range<int, bidirectional_iterator_wrapper> rx(x);
  49   auto v = rx | views::drop_while([] (int i) { return i<4; });
  50   VERIFY( ranges::equal(v, (int[]){4,5}) );
  51   using R = decltype(v);
  52   static_assert(ranges::view<R>);
  53   static_assert(!ranges::common_range<R>);
  54   static_assert(ranges::bidirectional_range<R>);
  55 }
  56
  57 int
  58 main()
  59 {
  60   test01();
  61   test02();
  62 }
  63