ferron/util/
sizify.rs

1// Sizify function taken from SVR.JS and rewritten from JavaScript to Rust
2// SVR.JS is licensed under MIT, so below is the copyright notice:
3//
4// Copyright (c) 2018-2025 SVR.JS
5// Portions of this file are derived from SVR.JS (https://git.svrjs.org/svrjs/svrjs).
6//
7// Permission is hereby granted, free of charge, to any person obtaining a copy
8// of this software and associated documentation files (the "Software"), to deal
9// in the Software without restriction, including without limitation the rights
10// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11// copies of the Software, and to permit persons to whom the Software is
12// furnished to do so, subject to the following conditions:
13//
14// The above copyright notice and this permission notice shall be included in all
15// copies or substantial portions of the Software.
16//
17pub fn sizify(bytes: u64, add_i: bool) -> String {
18  if bytes == 0 {
19    return "0".to_string();
20  }
21
22  let prefixes = ["", "K", "M", "G", "T", "P", "E", "Z", "Y", "R", "Q"];
23  let prefix_index = ((bytes as f64).log2() / 10.0)
24    .floor()
25    .min(prefixes.len() as f64 - 1.0) as usize;
26  let prefix_index_translated = 2_i64.pow(10 * prefix_index as u32);
27  let decimal_points = ((2.0
28    - (bytes as f64 / prefix_index_translated as f64)
29      .log10()
30      .floor()) as i32)
31    .max(0);
32
33  let size = ((bytes as f64 / prefix_index_translated as f64) * 10_f64.powi(decimal_points)).ceil()
34    / 10_f64.powi(decimal_points);
35  let prefix = prefixes[prefix_index];
36  let suffix = if prefix_index > 0 && add_i { "i" } else { "" };
37
38  format!("{}{}{}", size, prefix, suffix)
39}
40
41#[cfg(test)]
42mod tests {
43  use super::*;
44
45  #[test]
46  fn test_sizify_zero_bytes() {
47    assert_eq!(sizify(0, false), "0");
48  }
49
50  #[test]
51  fn test_sizify_small_values() {
52    assert_eq!(sizify(1000, false), "1000");
53    assert_eq!(sizify(1024, false), "1K");
54  }
55
56  #[test]
57  fn test_sizify_larger_values() {
58    assert_eq!(sizify(1048576, false), "1M");
59    assert_eq!(sizify(1073741824, false), "1G");
60    assert_eq!(sizify(1099511627776, false), "1T");
61    assert_eq!(sizify(1125899906842624, false), "1P");
62    assert_eq!(sizify(1152921504606846976, false), "1E");
63  }
64
65  #[test]
66  fn test_sizify_add_i_suffix() {
67    assert_eq!(sizify(1024, true), "1Ki");
68    assert_eq!(sizify(1048576, true), "1Mi");
69    assert_eq!(sizify(1073741824, true), "1Gi");
70  }
71
72  #[test]
73  fn test_sizify_no_i_suffix() {
74    assert_eq!(sizify(1024, false), "1K");
75    assert_eq!(sizify(1048576, false), "1M");
76    assert_eq!(sizify(1073741824, false), "1G");
77  }
78
79  #[test]
80  fn test_sizify_decimal_points() {
81    assert_eq!(sizify(1500, false), "1.47K");
82    assert_eq!(sizify(1500000, false), "1.44M");
83    assert_eq!(sizify(1500000000, false), "1.4G");
84  }
85
86  #[test]
87  fn test_sizify_edge_cases() {
88    assert_eq!(sizify(1, false), "1");
89    assert_eq!(sizify(1023, false), "1023");
90    assert_eq!(sizify(1025, false), "1.01K");
91  }
92}
ferron/util/sizify.rs

ferron/util/
sizify.rs
