This represents the first breaking change in a new release series,
bumping all crates to the 2024 edition of Rust.
As such, the version numbers of all crates have been incremented to
represent a new prerelease series:
- `curve25519-dalek`: v5.0.0-pre
- `ed25519-dalek`: v3.0.0-pre
- `x25519-dalek`: v3.0.0-pre
Note that this commit isn't intended to cut associated crate releases of
these on crates.io, but is merely bumping the version numbers to denote
there are pending breaking changes.
This commit also includes rustfmt changes which were made as part of the
2024 edition.
Also includes clippy fixes.
* curve: extract `AffinePoint` type
Based on discussions about `elliptic-curve` trait impls in #746, and
observing a similar type in `ed448-goldilocks` which inspired this one
(not to mention in all of the @RustCrypto elliptic curve crates), adds
an `AffinePoint` type with `x` and `y` coordinates.
For now, the type is kept out of the public API, and used as an
implementation detail for point compression. However, it's been written
with the intent of eventually stabilizing and exposing it. It's been
marked `pub` so unused functionality doesn't automatically trigger dead
code lints.
Further work could include refactoring point decompression to first
produce an `AffinePoint` and then convert to extended twisted Edwards
coordinates (i.e. `EdwardsPoint`), which is more or less what the
existing `step_1` and `step_2` functions do (`step_1` technically
produces projective coordinates, but `Z` is always set to `ONE`).
* Update curve25519-dalek/src/edwards.rs
