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pub mod kind;
use std::{error, fmt, num, str::FromStr};
pub use self::kind::Kind;
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub struct Op {
kind: Kind,
len: u32,
}
impl Op {
pub fn new(kind: Kind, len: u32) -> Self {
Self { kind, len }
}
pub fn kind(self) -> Kind {
self.kind
}
pub fn len(self) -> u32 {
self.len
}
pub fn is_empty(self) -> bool {
self.len == 0
}
}
impl fmt::Display for Op {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "{}{}", self.len(), self.kind())
}
}
#[derive(Clone, Debug, Eq, PartialEq)]
pub enum ParseError {
Empty,
InvalidLength(num::ParseIntError),
InvalidKind(kind::ParseError),
}
impl error::Error for ParseError {}
impl fmt::Display for ParseError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
Self::Empty => write!(f, "empty input"),
Self::InvalidLength(e) => write!(f, "invalid length: {}", e),
Self::InvalidKind(e) => write!(f, "invalid kind: {}", e),
}
}
}
impl FromStr for Op {
type Err = ParseError;
fn from_str(s: &str) -> Result<Self, Self::Err> {
if s.is_empty() {
return Err(ParseError::Empty);
}
let (raw_len, raw_kind) = s.split_at(s.len() - 1);
let len = raw_len.parse().map_err(ParseError::InvalidLength)?;
let kind = raw_kind.parse().map_err(ParseError::InvalidKind)?;
Ok(Self::new(kind, len))
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_fmt() {
let op = Op::new(Kind::Match, 5);
assert_eq!(op.to_string(), "5M");
let op = Op::new(Kind::SoftClip, 13);
assert_eq!(op.to_string(), "13S");
}
#[test]
fn test_from_str() -> Result<(), ParseError> {
assert_eq!("1M".parse(), Ok(Op::new(Kind::Match, 1)));
assert_eq!("13N".parse(), Ok(Op::new(Kind::Skip, 13)));
assert_eq!("144S".parse(), Ok(Op::new(Kind::SoftClip, 144)));
assert_eq!("".parse::<Op>(), Err(ParseError::Empty));
assert!(matches!(
"Z".parse::<Op>(),
Err(ParseError::InvalidLength(_))
));
assert!(matches!(
"21".parse::<Op>(),
Err(ParseError::InvalidKind(_))
));
Ok(())
}
}