1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42

// This is a part of Chrono.
// Portions Copyright 2013-2014 The Rust Project Developers.
// See README.md and LICENSE.txt for details.

//! Integer division utilities. (Shamelessly copied from [num](https://github.com/rust-lang/num/))

// Algorithm from [Daan Leijen. _Division and Modulus for Computer Scientists_,
// December 2001](http://research.microsoft.com/pubs/151917/divmodnote-letter.pdf)

pub use num_integer::{div_rem, div_floor, mod_floor, div_mod_floor};

#[cfg(test)]
mod tests {
    use super::{mod_floor, div_mod_floor};

    #[test]
    fn test_mod_floor() {
        assert_eq!(mod_floor( 8,  3),  2);
        assert_eq!(mod_floor( 8, -3), -1);
        assert_eq!(mod_floor(-8,  3),  1);
        assert_eq!(mod_floor(-8, -3), -2);

        assert_eq!(mod_floor( 1,  2),  1);
        assert_eq!(mod_floor( 1, -2), -1);
        assert_eq!(mod_floor(-1,  2),  1);
        assert_eq!(mod_floor(-1, -2), -1);
    }

    #[test]
    fn test_div_mod_floor() {
        assert_eq!(div_mod_floor( 8,  3), ( 2,  2));
        assert_eq!(div_mod_floor( 8, -3), (-3, -1));
        assert_eq!(div_mod_floor(-8,  3), (-3,  1));
        assert_eq!(div_mod_floor(-8, -3), ( 2, -2));

        assert_eq!(div_mod_floor( 1,  2), ( 0,  1));
        assert_eq!(div_mod_floor( 1, -2), (-1, -1));
        assert_eq!(div_mod_floor(-1,  2), (-1,  1));
        assert_eq!(div_mod_floor(-1, -2), ( 0, -1));
    }
}