Struct Hash 

pub struct Hash(/* private fields */);

Re-exports of the core data structures.

Purpose

All version-control objects (Blob, Tree, Commit, Tag) and their supporting types are available directly from the crate root for ergonomic access.

Examples

use libvctrl::Blob;
let blob = Blob::new(vec![1, 2, 3]);
assert_eq!(blob.size(), 3);

A 64-byte cryptographic hash used to identify version control objects.

Purpose

This type represents the output of a 512-bit hash function (like SHA-512). It is used to address and retrieve objects in the ObjectStore.

Design rationale

By wrapping the byte array in a tuple struct, we prevent type confusion with other 64-byte arrays. The inner array is private to ensure it can only be constructed via Hash::from_bytes, which enforces the length invariant.

Examples

use libvctrl_handler::Hash;

let bytes = [0u8; 64];
let hash = Hash::from_bytes(&bytes).unwrap();
assert_eq!(hash.as_bytes(), &bytes);

Implementations

impl Hash

pub const fn from_bytes(bytes: &[u8]) -> Result<Hash, VctrlError>

Creates a Hash from a slice of bytes.

Design rationale

This is a const fn to allow compile-time construction of hashes. The while loop is used because for loops and slice iterators were historically not stable in const contexts.

Errors

Returns VctrlError::InvalidHashLength if the length of bytes is not exactly HASH_LENGTH.

Examples

use libvctrl_handler::{Hash, VctrlError};

let valid = Hash::from_bytes(&[0u8; 64]);
assert!(valid.is_ok());

let invalid = Hash::from_bytes(&[0u8; 32]);
assert!(matches!(invalid, Err(VctrlError::InvalidHashLength(32))));

pub const fn as_bytes(&self) -> &[u8; 64]

Returns the hash as a fixed-size byte array reference.

Examples

use libvctrl_handler::Hash;

let bytes = [1u8; 64];
let hash = Hash::from_bytes(&bytes).unwrap();
assert_eq!(hash.as_bytes(), &bytes);

Trait Implementations

impl Clone for Hash

fn clone(&self) -> Hash

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for Hash

impl Debug for Hash

Formats the hash for debugging purposes.

Design rationale

The default Debug implementation for arrays would print all 64 bytes, which clutters log output. This implementation prints only the first 8 bytes (16 hex characters) followed by an ellipsis, which is sufficient to distinguish between different hashes in logs.

Examples

use libvctrl_handler::Hash;

let bytes = [0u8; 64];
let hash = Hash::from_bytes(&bytes).unwrap();
assert_eq!(format!("{hash:?}"), "Hash(0000000000000000…)");

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Display for Hash

Formats the hash as a lowercase hexadecimal string.

Design rationale

Hexadecimal is the standard representation for cryptographic hashes in version control systems (e.g., Git object IDs). This implementation is zero-allocation and writes directly to the formatter.

Examples

use libvctrl_handler::Hash;

let bytes = [0u8; 64];
let hash = Hash::from_bytes(&bytes).unwrap();
assert_eq!(format!("{hash}"), "00".repeat(64));

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Eq for Hash

impl Hash for Hash

fn hash<__H>(&self, state: &mut __H)

where __H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Hash

fn cmp(&self, other: &Hash) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for Hash

fn eq(&self, other: &Hash) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl PartialOrd for Hash

fn partial_cmp(&self, other: &Hash) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl StructuralPartialEq for Hash