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 // <functional>
12
13 // Make sure that we can hash enumeration values.
14
15 #include "test_macros.h"
16
17 #include <functional>
18 #include <cassert>
19 #include <type_traits>
20 #include <limits>
21
22 enum class Colors { red, orange, yellow, green, blue, indigo, violet };
23 enum class Cardinals { zero, one, two, three, five=5 };
24 enum class LongColors : short { red, orange, yellow, green, blue, indigo, violet };
25 enum class ShortColors : long { red, orange, yellow, green, blue, indigo, violet };
26 enum class EightBitColors : uint8_t { red, orange, yellow, green, blue, indigo, violet };
27
28 enum Fruits { apple, pear, grape, mango, cantaloupe };
29
30 template <class T>
31 void
test()32 test()
33 {
34 typedef std::hash<T> H;
35 #if TEST_STD_VER <= 17
36 static_assert((std::is_same<typename H::argument_type, T>::value), "");
37 static_assert((std::is_same<typename H::result_type, std::size_t>::value), "");
38 #endif
39 ASSERT_NOEXCEPT(H()(T()));
40 typedef typename std::underlying_type<T>::type under_type;
41
42 H h1;
43 std::hash<under_type> h2;
44 for (int i = 0; i <= 5; ++i)
45 {
46 T t(static_cast<T> (i));
47 const bool small = std::integral_constant<bool, sizeof(T) <= sizeof(std::size_t)>::value; // avoid compiler warnings
48 if (small)
49 assert(h1(t) == h2(static_cast<under_type>(i)));
50 }
51 }
52
main(int,char **)53 int main(int, char**)
54 {
55 test<Cardinals>();
56
57 test<Colors>();
58 test<ShortColors>();
59 test<LongColors>();
60 test<EightBitColors>();
61
62 test<Fruits>();
63
64 return 0;
65 }
66