twox-hash

Changed

• The documentation has been updated to account for XxHash3_128.

Changed

• The version range for the optional rand dependency is now 0.9.

Added

• The XXH3 128-bit algorithm is implemented via XxHash3_128 and the xxhash3_128 module.

Fixed

• Removed a panic that could occur when using XxHash3_64 to hash 1 to 3 bytes of data in debug mode. Release mode and different lengths of data are unaffected.

This release is a complete rewrite of the crate, including reorganization of the code. The XXH3 algorithm now matches the 0.8 release of the reference C xxHash implementation.

Added

• XxHash32::oneshot and XxHash64::oneshot can perform hashing with zero allocation and generally improved performance. If you have code that creates a hasher and hashes a slice of bytes exactly once, you are strongly encouraged to use the new functions. This might look like:

  // Before
  let mut hasher = XxHash64::new(); // or XxHash32, or with seeds
  some_bytes.hash(&mut hasher);
  let hash = hasher.finish();
  
  // After
  let hash = XxHash64::oneshot(some_bytes);
  

• There is a feature flag for each hashing implementation. It is recommended that you opt-out of the crate's default features and only select the implementations you need to improve compile speed.

Changed

• The crates minimum supported Rust version (MSRV) is now 1.81.

• Functional and performance comparisons are made against the reference C xxHash library version 0.8.2, which includes a stable XXH3 algorithm.

• Support for randomly-generated hasher instances is now behind the random feature flag. It was previously combined with the std feature flag.

Removed

• The deprecated type aliases XxHash and RandomXxHashBuilder have been removed. Replace them with XxHash64 and xxhash64::RandomState respectively.

• RandomXxHashBuilder32 and RandomXxHashBuilder64 are no longer available at the top-level of the crate. Replace them with xxhash32::RandomState and xxhash64::RandomState respectively.

• Xxh3Hash64 and xx3::Hash64 have been renamed to XxHash3_64 and xxhash3_64::Hasher respectively.

• The free functions xxh3::hash64, xxh3::hash64_with_seed, and xxh3::hash64_with_secret are now associated functions of xxhash3_64::Hasher: oneshot, oneshot_with_seed and oneshot_with_secret. Note that the argument order has changed.

• Support for the digest crate has been removed. The digest crate is for cryptographic hash functions and xxHash is non-cryptographic.

• XxHash32 and XxHash64 no longer implement Copy. This prevents accidentally mutating a duplicate instance of the state instead of the original state. Clone is still implemented so you can make deliberate duplicates.

• The XXH3 128-bit variant is not yet re-written. Work is in progress for this.

• We no longer provide support for randomly-generated instances of the XXH3 64-bit variant. The XXH3 algorithm takes both a seed and a secret as input and deciding what to randomize is non-trivial and can have negative impacts on performance.