libstdc++-v3/testsuite/24_iterators/move_iterator/p2520r0.cc

   1 // { dg-options "-std=gnu++20" }
   2 // { dg-do compile { target c++20 } }
   3
   4 // Verify P2520R0 changes to move_iterator's iterator_concept, which we treat
   5 // as a DR against C++20.
   6
   7 #include <iterator>
   8 #if __cpp_lib_move_iterator_concept != 202207L
   9 # error "Feature-test macro __cpp_lib_move_iterator_concept has wrong value in <iterator>"
  10 #endif
  11
  12 #undef __cpp_lib_move_iterator_concept
  13 #include <version>
  14 #if __cpp_lib_move_iterator_concept != 202207L
  15 # error "Feature-test macro __cpp_lib_move_iterator_concept has wrong value in <version>"
  16 #endif
  17
  18 #include <testsuite_iterators.h>
  19
  20 using __gnu_test::test_input_range;
  21 using __gnu_test::test_forward_range;
  22 using __gnu_test::test_bidirectional_range;
  23 using __gnu_test::test_random_access_range;
  24
  25 using ty1 = std::move_iterator<decltype(std::declval<test_input_range<int>&>().begin())>;
  26 static_assert(std::same_as<ty1::iterator_concept, std::input_iterator_tag>);
  27
  28 using ty2 = std::move_iterator<decltype(std::declval<test_forward_range<int>&>().begin())>;
  29 static_assert(std::same_as<ty2::iterator_concept, std::forward_iterator_tag>);
  30
  31 using ty3 = std::move_iterator<decltype(std::declval<test_bidirectional_range<int>&>().begin())>;
  32 static_assert(std::same_as<ty3::iterator_concept, std::bidirectional_iterator_tag>);
  33
  34 using ty4 = std::move_iterator<decltype(std::declval<test_random_access_range<int>&>().begin())>;
  35 static_assert(std::same_as<ty4::iterator_concept, std::random_access_iterator_tag>);
  36
  37 static_assert(std::random_access_iterator<std::move_iterator<int*>>);