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 | // <algorithm> |
10 | // XFAIL: c++03, c++11, c++14 |
11 | |
12 | // template<class T> |
13 | // const T& |
14 | // clamp(const T& v, const T& lo, const T& hi); |
15 | |
16 | #include <algorithm> |
17 | #include <cassert> |
18 | |
19 | #include "test_macros.h" |
20 | |
21 | struct Tag { |
22 | Tag() : val(0), tag("Default" ) {} |
23 | Tag(int a, const char *b) : val(a), tag(b) {} |
24 | ~Tag() {} |
25 | |
26 | int val; |
27 | const char *tag; |
28 | }; |
29 | |
30 | bool eq(const Tag& rhs, const Tag& lhs) { return rhs.val == lhs.val && rhs.tag == lhs.tag; } |
31 | // bool operator==(const Tag& rhs, const Tag& lhs) { return rhs.val == lhs.val; } |
32 | bool operator< (const Tag& rhs, const Tag& lhs) { return rhs.val < lhs.val; } |
33 | |
34 | template <class T> |
35 | void |
36 | test(const T& a, const T& lo, const T& hi, const T& x) |
37 | { |
38 | assert(&std::clamp(a, lo, hi) == &x); |
39 | } |
40 | |
41 | int main(int, char**) |
42 | { |
43 | { |
44 | int x = 0; |
45 | int y = 0; |
46 | int z = 0; |
47 | test(a: x, lo: y, hi: z, x); |
48 | test(a: y, lo: x, hi: z, x: y); |
49 | } |
50 | { |
51 | int x = 0; |
52 | int y = 1; |
53 | int z = 2; |
54 | test(a: x, lo: y, hi: z, x: y); |
55 | test(a: y, lo: x, hi: z, x: y); |
56 | } |
57 | { |
58 | int x = 1; |
59 | int y = 0; |
60 | int z = 1; |
61 | test(a: x, lo: y, hi: z, x); |
62 | test(a: y, lo: x, hi: z, x); |
63 | } |
64 | |
65 | { |
66 | // If they're all the same, we should get the value back. |
67 | Tag x{0, "Zero-x" }; |
68 | Tag y{0, "Zero-y" }; |
69 | Tag z{0, "Zero-z" }; |
70 | assert(eq(std::clamp(x, y, z), x)); |
71 | assert(eq(std::clamp(y, x, z), y)); |
72 | } |
73 | |
74 | { |
75 | // If it's the same as the lower bound, we get the value back. |
76 | Tag x{0, "Zero-x" }; |
77 | Tag y{0, "Zero-y" }; |
78 | Tag z{1, "One-z" }; |
79 | assert(eq(std::clamp(x, y, z), x)); |
80 | assert(eq(std::clamp(y, x, z), y)); |
81 | } |
82 | |
83 | { |
84 | // If it's the same as the upper bound, we get the value back. |
85 | Tag x{1, "One-x" }; |
86 | Tag y{0, "Zero-y" }; |
87 | Tag z{1, "One-z" }; |
88 | assert(eq(std::clamp(x, y, z), x)); |
89 | assert(eq(std::clamp(z, y, x), z)); |
90 | } |
91 | |
92 | { |
93 | // If the value is between, we should get the value back |
94 | Tag x{1, "One-x" }; |
95 | Tag y{0, "Zero-y" }; |
96 | Tag z{2, "Two-z" }; |
97 | assert(eq(std::clamp(x, y, z), x)); |
98 | assert(eq(std::clamp(y, x, z), x)); |
99 | } |
100 | |
101 | { |
102 | // If the value is less than the 'lo', we should get the lo back. |
103 | Tag x{0, "Zero-x" }; |
104 | Tag y{1, "One-y" }; |
105 | Tag z{2, "Two-z" }; |
106 | assert(eq(std::clamp(x, y, z), y)); |
107 | assert(eq(std::clamp(y, x, z), y)); |
108 | } |
109 | { |
110 | // If the value is greater than 'hi', we should get hi back. |
111 | Tag x{2, "Two-x" }; |
112 | Tag y{0, "Zero-y" }; |
113 | Tag z{1, "One-z" }; |
114 | assert(eq(std::clamp(x, y, z), z)); |
115 | assert(eq(std::clamp(y, z, x), z)); |
116 | } |
117 | |
118 | { |
119 | typedef int T; |
120 | constexpr T x = 1; |
121 | constexpr T y = 0; |
122 | constexpr T z = 1; |
123 | static_assert(std::clamp(val: x, lo: y, hi: z) == x, "" ); |
124 | static_assert(std::clamp(val: y, lo: x, hi: z) == x, "" ); |
125 | } |
126 | |
127 | return 0; |
128 | } |
129 | |