JenkHash 0.2.1

Bob Jenkins hash functions for Rust with a digest-compatible API.
Documentation 
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//! Implementation of the one-at-a-time hash algorithm.
//!
//! The one-at-a-time hash is a simple, fast hash function designed for hash tables.
//! It provides good distribution properties for typical use cases while being
//! computationally efficient.

use crate::hash::Hasher;

/// A hasher implementing the one-at-a-time hash algorithm.
///
/// This hash function processes input data incrementally and produces a 32-bit hash value.
/// It implements the [`Hasher`](crate::hash::Hasher) trait, allowing it to be used with
/// the unified hashing API.
///
/// # Examples
///
/// ```
/// use JenkHash::{Hasher, OneAtATime};
///
/// let mut hasher = OneAtATime::new();
/// hasher.write(b"hello");
/// hasher.write(b" world");
/// let hash = hasher.finalize();
///
/// assert_eq!(hash, 1045060183);
/// ```
pub struct OneAtATime {
    state: u32,
}

impl Hasher for OneAtATime {
    type Output = u32;

    fn new() -> Self {
        Self { state: 0 }
    }

    fn write(&mut self, input: &[u8]) {
        for &b in input {
            self.state = self.state.wrapping_add(b as u32);
            self.state = self.state.wrapping_add(self.state << 10);
            self.state ^= self.state >> 6;
        }
    }
    fn finalize(mut self) -> Self::Output {
        self.state = self.state.wrapping_add(self.state << 3);
        self.state ^= self.state >> 11;
        self.state = self.state.wrapping_add(self.state << 15);

        self.state
    }
}


#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_simple() {
        let mut hasher = OneAtATime::new();
        hasher.write(b"kt1_lod_1_2_5_6_17");
        let hash = hasher.finalize();

        assert_eq!(hash, 373823972);
    }
}