chunked-wal 0.2.0

Chunked write-ahead log implementation
Documentation 
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use std::fmt;
use std::ops::Deref;

use crate::num::format_pad_u64;

/// ChunkId represents a unique identifier for a chunk based on its global
/// offset in the log.
///
/// Each chunk in the log has a unique position identified by its starting
/// offset. This offset serves as the chunk's identifier and can be used to
/// locate and reference specific chunks within the log.
#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub struct ChunkId(pub u64);

impl fmt::Display for ChunkId {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "ChunkId({})", format_pad_u64(self.0))
    }
}

impl From<u64> for ChunkId {
    fn from(offset: u64) -> Self {
        ChunkId(offset)
    }
}

impl Deref for ChunkId {
    type Target = u64;

    fn deref(&self) -> &Self::Target {
        &self.0
    }
}

impl ChunkId {
    /// Returns the global offset where this chunk begins in the log.
    ///
    /// The offset is a monotonically increasing value that represents the
    /// absolute position of the chunk in the entire log sequence.
    pub fn offset(&self) -> u64 {
        self.0
    }
}

#[cfg(test)]
mod tests {
    use crate::ChunkId;

    #[test]
    fn test_chunk_id_format_and_accessors() {
        let chunk_id = ChunkId::from(1_200_000);

        assert_eq!(1_200_000, *chunk_id);
        assert_eq!(1_200_000, chunk_id.offset());
        assert_eq!("ChunkId(00_000_000_000_001_200_000)", chunk_id.to_string());
    }
}