xref: /llvm-project/libcxx/test/std/numerics/numeric.ops/numeric.ops.midpoint/midpoint.integer.pass.cpp (revision 330ab33f7c137ad3debd813ab7e7599e44e19346)
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 // UNSUPPORTED: c++98, c++03, c++11, c++14, c++17
10 // <numeric>
11 
12 // template <class _Tp>
13 // _Tp midpoint(_Tp __a, _Tp __b) noexcept
14 //
15 
16 #include <numeric>
17 #include <cassert>
18 #include "test_macros.h"
19 
20 template <typename T>
21 void signed_test()
22 {
23     constexpr T zero{0};
24     constexpr T one{1};
25     constexpr T two{2};
26     constexpr T three{3};
27     constexpr T four{4};
28 
29     ASSERT_SAME_TYPE(decltype(std::midpoint(T(), T())), T);
30     ASSERT_NOEXCEPT(          std::midpoint(T(), T()));
31     using limits = std::numeric_limits<T>;
32 
33     static_assert(std::midpoint(one, three) == two, "");
34     static_assert(std::midpoint(three, one) == two, "");
35 
36     assert(std::midpoint(zero, zero) == zero);
37     assert(std::midpoint(zero, two)  == one);
38     assert(std::midpoint(two, zero)  == one);
39     assert(std::midpoint(two, two)   == two);
40 
41     assert(std::midpoint(one, four)    == two);
42     assert(std::midpoint(four, one)    == three);
43     assert(std::midpoint(three, four)  == three);
44     assert(std::midpoint(four, three)  == four);
45 
46     assert(std::midpoint(T( 3), T( 4)) == T(3));
47     assert(std::midpoint(T( 4), T( 3)) == T(4));
48     assert(std::midpoint(T(-3), T( 4)) == T(0));
49     assert(std::midpoint(T(-4), T( 3)) == T(-1));
50     assert(std::midpoint(T( 3), T(-4)) == T(0));
51     assert(std::midpoint(T( 4), T(-3)) == T(1));
52     assert(std::midpoint(T(-3), T(-4)) == T(-3));
53     assert(std::midpoint(T(-4), T(-3)) == T(-4));
54 
55     static_assert(std::midpoint(limits::min(), limits::max()) == T(-1), "");
56     static_assert(std::midpoint(limits::max(), limits::min()) == T( 0), "");
57 
58     static_assert(std::midpoint(limits::min(), T(6)) == limits::min()/2 + 3, "");
59     assert(       std::midpoint(T(6), limits::min()) == limits::min()/2 + 3);
60     assert(       std::midpoint(limits::max(), T(6)) == limits::max()/2 + 4);
61     static_assert(std::midpoint(T(6), limits::max()) == limits::max()/2 + 3, "");
62 
63     assert(       std::midpoint(limits::min(), T(-6)) == limits::min()/2 - 3);
64     static_assert(std::midpoint(T(-6), limits::min()) == limits::min()/2 - 3, "");
65     static_assert(std::midpoint(limits::max(), T(-6)) == limits::max()/2 - 2, "");
66     assert(       std::midpoint(T(-6), limits::max()) == limits::max()/2 - 3);
67 }
68 
69 template <typename T>
70 void unsigned_test()
71 {
72     constexpr T zero{0};
73     constexpr T one{1};
74     constexpr T two{2};
75     constexpr T three{3};
76     constexpr T four{4};
77 
78     ASSERT_SAME_TYPE(decltype(std::midpoint(T(), T())), T);
79     ASSERT_NOEXCEPT(          std::midpoint(T(), T()));
80     using limits = std::numeric_limits<T>;
81     const T half_way = (limits::max() - limits::min())/2;
82 
83     static_assert(std::midpoint(one, three) == two, "");
84     static_assert(std::midpoint(three, one) == two, "");
85 
86     assert(std::midpoint(zero, zero) == zero);
87     assert(std::midpoint(zero, two)  == one);
88     assert(std::midpoint(two, zero)  == one);
89     assert(std::midpoint(two, two)   == two);
90 
91     assert(std::midpoint(one, four)    == two);
92     assert(std::midpoint(four, one)    == three);
93     assert(std::midpoint(three, four)  == three);
94     assert(std::midpoint(four, three)  == four);
95 
96     assert(std::midpoint(limits::min(), limits::max()) == T(half_way));
97     assert(std::midpoint(limits::max(), limits::min()) == T(half_way + 1));
98 
99     static_assert(std::midpoint(limits::min(), T(6)) == limits::min()/2 + 3, "");
100     assert(       std::midpoint(T(6), limits::min()) == limits::min()/2 + 3);
101     assert(       std::midpoint(limits::max(), T(6)) == half_way + 4);
102     static_assert(std::midpoint(T(6), limits::max()) == half_way + 3, "");
103 }
104 
105 
106 int main(int, char**)
107 {
108     signed_test<signed char>();
109     signed_test<short>();
110     signed_test<int>();
111     signed_test<long>();
112     signed_test<long long>();
113 
114     signed_test<int8_t>();
115     signed_test<int16_t>();
116     signed_test<int32_t>();
117     signed_test<int64_t>();
118     signed_test<__int128_t>();
119 
120     unsigned_test<unsigned char>();
121     unsigned_test<unsigned short>();
122     unsigned_test<unsigned int>();
123     unsigned_test<unsigned long>();
124     unsigned_test<unsigned long long>();
125 
126     unsigned_test<uint8_t>();
127     unsigned_test<uint16_t>();
128     unsigned_test<uint32_t>();
129     unsigned_test<uint64_t>();
130     unsigned_test<__uint128_t>();
131 
132 //     int_test<char>();
133     signed_test<ptrdiff_t>();
134     unsigned_test<size_t>();
135 
136     return 0;
137 }
138