1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 // ADDITIONAL_COMPILE_FLAGS: -D_LIBCPP_DISABLE_DEPRECATION_WARNINGS 10 11 // UNSUPPORTED: c++03, c++11 12 13 // <functional> 14 15 // make sure that we can hash enumeration values 16 // Not very portable 17 18 #include "test_macros.h" 19 20 #include <functional> 21 #include <cassert> 22 #include <type_traits> 23 #include <limits> 24 25 enum class Colors { red, orange, yellow, green, blue, indigo, violet }; 26 enum class Cardinals { zero, one, two, three, five=5 }; 27 enum class LongColors : short { red, orange, yellow, green, blue, indigo, violet }; 28 enum class ShortColors : long { red, orange, yellow, green, blue, indigo, violet }; 29 enum class EightBitColors : uint8_t { red, orange, yellow, green, blue, indigo, violet }; 30 31 enum Fruits { apple, pear, grape, mango, cantaloupe }; 32 33 template <class T> 34 void 35 test() 36 { 37 typedef std::hash<T> H; 38 #if TEST_STD_VER <= 17 39 static_assert((std::is_same<typename H::argument_type, T>::value), ""); 40 static_assert((std::is_same<typename H::result_type, std::size_t>::value), ""); 41 #endif 42 ASSERT_NOEXCEPT(H()(T())); 43 typedef typename std::underlying_type<T>::type under_type; 44 45 H h1; 46 std::hash<under_type> h2; 47 for (int i = 0; i <= 5; ++i) 48 { 49 T t(static_cast<T> (i)); 50 const bool small = std::integral_constant<bool, sizeof(T) <= sizeof(std::size_t)>::value; // avoid compiler warnings 51 if (small) 52 assert(h1(t) == h2(static_cast<under_type>(i))); 53 } 54 } 55 56 int main(int, char**) 57 { 58 test<Cardinals>(); 59 60 test<Colors>(); 61 test<ShortColors>(); 62 test<LongColors>(); 63 test<EightBitColors>(); 64 65 test<Fruits>(); 66 67 return 0; 68 } 69