1 // Translated from C to Rust. The original C code can be found at
2 // https://github.com/ulfjack/ryu and carries the following license:
3 //
4 // Copyright 2018 Ulf Adams
5 //
6 // The contents of this file may be used under the terms of the Apache License,
7 // Version 2.0.
8 //
9 //    (See accompanying file LICENSE-Apache or copy at
10 //     http://www.apache.org/licenses/LICENSE-2.0)
11 //
12 // Alternatively, the contents of this file may be used under the terms of
13 // the Boost Software License, Version 1.0.
14 //    (See accompanying file LICENSE-Boost or copy at
15 //     https://www.boost.org/LICENSE_1_0.txt)
16 //
17 // Unless required by applicable law or agreed to in writing, this software
18 // is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
19 // KIND, either express or implied.
20 
21 #![allow(dead_code)]
22 #![allow(
23     clippy::cast_lossless,
24     clippy::cast_possible_truncation,
25     clippy::unreadable_literal
26 )]
27 
28 #[path = "../src/d2s_intrinsics.rs"]
29 mod d2s_intrinsics;
30 
31 use d2s_intrinsics::pow5_factor;
32 
33 #[test]
test_pow5_factor()34 fn test_pow5_factor() {
35     assert_eq!(0, pow5_factor(1));
36     assert_eq!(0, pow5_factor(2));
37     assert_eq!(0, pow5_factor(3));
38     assert_eq!(0, pow5_factor(4));
39     assert_eq!(1, pow5_factor(5));
40     assert_eq!(0, pow5_factor(6));
41     assert_eq!(0, pow5_factor(7));
42     assert_eq!(0, pow5_factor(8));
43     assert_eq!(0, pow5_factor(9));
44     assert_eq!(1, pow5_factor(10));
45 
46     assert_eq!(0, pow5_factor(12));
47     assert_eq!(0, pow5_factor(14));
48     assert_eq!(0, pow5_factor(16));
49     assert_eq!(0, pow5_factor(18));
50     assert_eq!(1, pow5_factor(20));
51 
52     assert_eq!(2, pow5_factor(5 * 5));
53     assert_eq!(3, pow5_factor(5 * 5 * 5));
54     assert_eq!(4, pow5_factor(5 * 5 * 5 * 5));
55     assert_eq!(5, pow5_factor(5 * 5 * 5 * 5 * 5));
56     assert_eq!(6, pow5_factor(5 * 5 * 5 * 5 * 5 * 5));
57     assert_eq!(7, pow5_factor(5 * 5 * 5 * 5 * 5 * 5 * 5));
58     assert_eq!(8, pow5_factor(5 * 5 * 5 * 5 * 5 * 5 * 5 * 5));
59     assert_eq!(9, pow5_factor(5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5));
60     assert_eq!(10, pow5_factor(5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5));
61 
62     assert_eq!(0, pow5_factor(42));
63     assert_eq!(1, pow5_factor(42 * 5));
64     assert_eq!(2, pow5_factor(42 * 5 * 5));
65     assert_eq!(3, pow5_factor(42 * 5 * 5 * 5));
66     assert_eq!(4, pow5_factor(42 * 5 * 5 * 5 * 5));
67     assert_eq!(5, pow5_factor(42 * 5 * 5 * 5 * 5 * 5));
68 
69     assert_eq!(27, pow5_factor(7450580596923828125)); // 5^27, largest power of 5 < 2^64.
70     assert_eq!(1, pow5_factor(18446744073709551615)); // 2^64 - 1, largest multiple of 5 < 2^64.
71     assert_eq!(0, pow5_factor(18446744073709551614)); // 2^64 - 2, largest non-multiple of 5 < 2^64.
72 }
73