dysk_cli/
units.rs

1use core::str::FromStr;
2
3/// The Units system used for sizes
4#[derive(Debug, Clone, Copy, PartialEq)]
5pub enum Units {
6    Si,     // Units according to the SI system, based on multiples of 1000
7    Binary, // Old binary based units, based on multiples of 1024
8    Bytes,  // Just the raw byte counts, with commas separating thousands
9}
10
11impl Default for Units {
12    fn default() -> Self {
13        Self::Si
14    }
15}
16impl FromStr for Units {
17    type Err = String;
18    fn from_str(value: &str) -> Result<Self, String> {
19        match value.to_lowercase().as_ref() {
20            "si" => Ok(Self::Si),
21            "binary" => Ok(Self::Binary),
22            "bytes" => Ok(Self::Bytes),
23            _ => Err(format!(
24                "Illegal value: {:?} - valid values are 'SI', 'binary', and 'bytes'",
25                value
26            )),
27        }
28    }
29}
30
31static PREFIXES: &[char] = &['K', 'M', 'G', 'T', 'P'];
32
33impl Units {
34    pub fn fmt(
35        self,
36        size: u64,
37    ) -> String {
38        match self {
39            Self::Si => file_size::fit_4(size),
40            Self::Binary => {
41                if size < 10_000 {
42                    size.to_string()
43                } else {
44                    let i = size.ilog2() / 10u32;
45                    let idx = i as usize - 1;
46                    let size = size as f64;
47                    if idx >= PREFIXES.len() {
48                        "huge".to_string()
49                    } else {
50                        let v = size / (1024u64.pow(i) as f64);
51                        if v >= 10f64 {
52                            format!("{:.0}{}i", v.round(), PREFIXES[idx])
53                        } else {
54                            format!("{:.1}{}i", v, PREFIXES[idx])
55                        }
56                    }
57                }
58            }
59            Self::Bytes => {
60                let mut rev: Vec<char> = Vec::new();
61                for (i, c) in size.to_string().chars().rev().enumerate() {
62                    if i > 0 && i % 3 == 0 {
63                        rev.push(',');
64                    }
65                    rev.push(c);
66                }
67                rev.drain(..).rev().collect()
68            }
69        }
70    }
71}
72
73#[test]
74fn test_fmt_binary() {
75    fn check(
76        v: u64,
77        s: &str,
78    ) {
79        assert_eq!(&Units::Binary.fmt(v), s);
80    }
81    check(0, "0");
82    check(1, "1");
83    check(456, "456");
84    check(1456, "1456");
85    check(9_999, "9999");
86    check(10_000, "9.8Ki");
87    check(12_345, "12Ki");
88    check(123_456, "121Ki");
89    check(1_000_000_000, "954Mi");
90    check(1_073_741_824, "1.0Gi");
91    check(1_234_567_890, "1.1Gi");
92}
93
94#[test]
95fn test_fmt_bytes() {
96    fn check(
97        v: u64,
98        s: &str,
99    ) {
100        assert_eq!(&Units::Bytes.fmt(v), s);
101    }
102    check(0, "0");
103    check(1, "1");
104    check(456, "456");
105    check(1456, "1,456");
106    check(9_999, "9,999");
107    check(10_000, "10,000");
108    check(12_345, "12,345");
109    check(123_456, "123,456");
110    check(1_234_567, "1,234,567");
111    check(1_000_000_000, "1,000,000,000");
112    check(1_234_567_890, "1,234,567,890");
113}
dysk_cli/units.rs

dysk_cli/
units.rs
