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| 1 | +use std::num::ParseIntError; |
| 2 | + |
| 3 | +#[derive(Debug, PartialEq)] |
| 4 | +pub enum ParseSizeError { |
| 5 | + InvalidFormat, |
| 6 | + InvalidSuffix, |
| 7 | + NumberTooLarge, |
| 8 | + ParseError(ParseIntError), |
| 9 | +} |
| 10 | + |
| 11 | +pub fn parse_number(input: &str) -> Result<u64, ParseIntError> { |
| 12 | + if let Some(stripped) = input.strip_prefix("0x") { |
| 13 | + u64::from_str_radix(stripped, 16) |
| 14 | + } else { |
| 15 | + input.parse() |
| 16 | + } |
| 17 | +} |
| 18 | + |
| 19 | +pub fn parse_size(input: &str) -> Result<u64, ParseSizeError> { |
| 20 | + if input.is_empty() { |
| 21 | + return Err(ParseSizeError::InvalidFormat); |
| 22 | + } |
| 23 | + |
| 24 | + let (num_part, suffix) = input.trim().split_at( |
| 25 | + input |
| 26 | + .find(|c: char| !c.is_ascii_digit() && c != 'x') |
| 27 | + .unwrap_or(input.len()), |
| 28 | + ); |
| 29 | + |
| 30 | + let num = parse_number(num_part).map_err(ParseSizeError::ParseError)?; |
| 31 | + |
| 32 | + let multiplier = match suffix.trim() { |
| 33 | + "B" => 1, |
| 34 | + "kB" => 1_024, |
| 35 | + "MB" => 1_024 * 1_024, |
| 36 | + "GB" => 1_024 * 1_024 * 1_024, |
| 37 | + "" => return Err(ParseSizeError::InvalidFormat), |
| 38 | + _ => return Err(ParseSizeError::InvalidSuffix), |
| 39 | + }; |
| 40 | + |
| 41 | + let result = num |
| 42 | + .checked_mul(multiplier as u64) |
| 43 | + .ok_or(ParseSizeError::NumberTooLarge)?; |
| 44 | + |
| 45 | + if result > u32::MAX as u64 { |
| 46 | + return Err(ParseSizeError::NumberTooLarge); |
| 47 | + } |
| 48 | + |
| 49 | + Ok(result) |
| 50 | +} |
| 51 | + |
| 52 | +#[cfg(test)] |
| 53 | +mod tests { |
| 54 | + use super::*; |
| 55 | + |
| 56 | + #[test] |
| 57 | + fn test_parse_number_decimal() { |
| 58 | + assert_eq!(parse_number("123"), Ok(123)); |
| 59 | + assert_eq!(parse_number("0"), Ok(0)); |
| 60 | + } |
| 61 | + |
| 62 | + #[test] |
| 63 | + fn test_parse_number_hexadecimal() { |
| 64 | + assert_eq!(parse_number("0x10"), Ok(16)); |
| 65 | + assert_eq!(parse_number("0x1F4"), Ok(500)); |
| 66 | + } |
| 67 | + |
| 68 | + #[test] |
| 69 | + fn test_parse_number_invalid() { |
| 70 | + assert!(parse_number("not_a_number").is_err()); |
| 71 | + assert!(parse_number("0xZZZ").is_err()); |
| 72 | + } |
| 73 | + |
| 74 | + #[test] |
| 75 | + fn test_parse_size_with_hexadecimal() { |
| 76 | + assert_eq!(parse_size("0x100B"), Ok(256)); |
| 77 | + assert_eq!(parse_size("0x1kB"), Ok(1_024)); |
| 78 | + assert_eq!(parse_size("0x2MB"), Ok(2 * 1_024 * 1_024)); |
| 79 | + } |
| 80 | + |
| 81 | + #[test] |
| 82 | + fn test_valid_sizes() { |
| 83 | + assert_eq!(parse_size("0B"), Ok(0)); |
| 84 | + assert_eq!(parse_size("256B"), Ok(256)); |
| 85 | + assert_eq!(parse_size("1kB"), Ok(1_024)); |
| 86 | + assert_eq!(parse_size("2MB"), Ok(2 * 1_024 * 1_024)); |
| 87 | + assert_eq!(parse_size("1GB"), Ok(1_024 * 1_024 * 1_024)); |
| 88 | + } |
| 89 | + |
| 90 | + #[test] |
| 91 | + fn test_invalid_formats() { |
| 92 | + assert_eq!(parse_size(""), Err(ParseSizeError::InvalidFormat)); |
| 93 | + assert_eq!(parse_size("256"), Err(ParseSizeError::InvalidFormat)); |
| 94 | + assert_eq!(parse_size("256MBExtra"), Err(ParseSizeError::InvalidSuffix)); |
| 95 | + } |
| 96 | + |
| 97 | + #[test] |
| 98 | + fn test_invalid_suffix() { |
| 99 | + assert_eq!(parse_size("256mB"), Err(ParseSizeError::InvalidSuffix)); |
| 100 | + assert_eq!(parse_size("256TB"), Err(ParseSizeError::InvalidSuffix)); |
| 101 | + } |
| 102 | + |
| 103 | + #[test] |
| 104 | + fn test_parse_errors() { |
| 105 | + assert!(matches!( |
| 106 | + parse_size("not_a_numberMB"), |
| 107 | + Err(ParseSizeError::ParseError(_)) |
| 108 | + )); |
| 109 | + assert!(matches!( |
| 110 | + parse_size("0xnot_hexB"), |
| 111 | + Err(ParseSizeError::ParseError(_)) |
| 112 | + )); |
| 113 | + } |
| 114 | +} |
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