Configure rustfmt

.cargo/license.rs

@@ -0,0 +1,6 @@
+// Copyright (c) Facebook, Inc. and its affiliates.
+//
+// This source code is licensed under both the MIT license found in the
+// LICENSE-MIT file in the root directory of this source tree and the Apache
+// License, Version 2.0 found in the LICENSE-APACHE file in the root directory
+// of this source tree.

.github/workflows/main.yml

@@ -113,11 +113,11 @@ jobs:
       - name: Checkout sources
         uses: actions/checkout@v2
 
-      - name: Install stable toolchain
+      - name: Install nightly toolchain
         uses: actions-rs/toolchain@v1
         with:
           profile: minimal
-          toolchain: stable
+          toolchain: nightly
           override: true
           components: rustfmt
 

rustfmt.toml

@@ -0,0 +1,8 @@
+format_code_in_doc_comments = true
+format_strings = true
+group_imports = "StdExternalCrate"
+imports_granularity = "Module"
+license_template_path = ".cargo/license.rs"
+newline_style = "Unix"
+unstable_features = true
+wrap_comments = true

src/group/expand.rs

@@ -5,15 +5,15 @@
 // License, Version 2.0 found in the LICENSE-APACHE file in the root directory
 // of this source tree.
 
-use crate::errors::InternalError;
-use crate::util::i2osp;
 use core::ops::Add;
+
 use digest::{BlockInput, Digest};
-use generic_array::{
-    sequence::Concat,
-    typenum::{Unsigned, U1, U2},
-    ArrayLength, GenericArray,
-};
+use generic_array::sequence::Concat;
+use generic_array::typenum::{Unsigned, U1, U2};
+use generic_array::{ArrayLength, GenericArray};
+
+use crate::errors::InternalError;
+use crate::util::i2osp;
 
 // Computes ceil(x / y)
 fn div_ceil(x: usize, y: usize) -> usize {
@@ -79,10 +79,8 @@ where
 
 #[cfg(test)]
 mod tests {
-    use generic_array::{
-        typenum::{U128, U32},
-        GenericArray,
-    };
+    use generic_array::typenum::{U128, U32};
+    use generic_array::GenericArray;
 
     struct Params {
         msg: &'static str,

src/group/mod.rs

@@ -22,14 +22,17 @@ cfg_ristretto! {
     mod ristretto;
 }
 
-use crate::errors::InternalError;
 use core::ops::{Add, Mul, Sub};
+
 use digest::{BlockInput, Digest};
-use generic_array::{typenum::U1, ArrayLength, GenericArray};
+use generic_array::typenum::U1;
+use generic_array::{ArrayLength, GenericArray};
 use rand_core::{CryptoRng, RngCore};
 use subtle::ConstantTimeEq;
 use zeroize::Zeroize;
 
+use crate::errors::InternalError;
+
 /// A prime-order subgroup of a base field (EC, prime-order field ...). This
 /// subgroup is noted additively — as in the draft RFC — in this trait.
 pub trait Group:
@@ -80,8 +83,8 @@ pub trait Group:
         scalar_bits: &GenericArray<u8, Self::ScalarLen>,
     ) -> Result<Self::Scalar, InternalError>;
 
-    /// Return a scalar from its fixed-length bytes representation. If the scalar
-    /// is zero, then return an error.
+    /// Return a scalar from its fixed-length bytes representation. If the
+    /// scalar is zero, then return an error.
     fn from_scalar_slice<'a>(
         scalar_bits: impl Into<&'a GenericArray<u8, Self::ScalarLen>>,
     ) -> Result<Self::Scalar, InternalError> {
@@ -103,14 +106,14 @@ pub trait Group:
     type ElemLen: ArrayLength<u8> + 'static;
 
     /// Return an element from its fixed-length bytes representation. This is
-    /// the unchecked version, which does not check for deserializing the identity
-    /// element
+    /// the unchecked version, which does not check for deserializing the
+    /// identity element
     fn from_element_slice_unchecked(
         element_bits: &GenericArray<u8, Self::ElemLen>,
     ) -> Result<Self, InternalError>;
 
-    /// Return an element from its fixed-length bytes representation. If the element
-    /// is the identity element, return an error.
+    /// Return an element from its fixed-length bytes representation. If the
+    /// element is the identity element, return an error.
     fn from_element_slice<'a>(
         element_bits: impl Into<&'a GenericArray<u8, Self::ElemLen>>,
     ) -> Result<Self, InternalError> {

src/group/p256.rs

@@ -5,18 +5,17 @@
 // License, Version 2.0 found in the LICENSE-APACHE file in the root directory
 // of this source tree.
 
-// Note: This group implementation of p256 is experimental for now,
-// until hash-to-curve or crypto-bigint are fully supported.
+// Note: This group implementation of p256 is experimental for now, until
+// hash-to-curve or crypto-bigint are fully supported.
 
 #![allow(
     clippy::borrow_interior_mutable_const,
     clippy::declare_interior_mutable_const
 )]
 
-use super::Group;
-use crate::errors::InternalError;
 use core::ops::{Add, Div, Mul, Neg};
 use core::str::FromStr;
+
 use digest::{BlockInput, Digest};
 use generic_array::typenum::{Unsigned, U1, U2, U32, U33, U48};
 use generic_array::{ArrayLength, GenericArray};
@@ -32,6 +31,9 @@ use p256_::{AffinePoint, EncodedPoint, ProjectivePoint};
 use rand_core::{CryptoRng, RngCore};
 use subtle::{Choice, ConditionallySelectable};
 
+use super::Group;
+use crate::errors::InternalError;
+
 // https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-hash-to-curve-11#section-8.2
 // `L: 48`
 pub type L = U48;
@@ -109,7 +111,9 @@ impl Group for ProjectivePoint {
         <D as Add<U1>>::Output: ArrayLength<u8>,
     {
         // https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.186-4.pdf#[{%22num%22:211,%22gen%22:0},{%22name%22:%22XYZ%22},70,700,0]
-        // P-256 `n` is defined as `115792089210356248762697446949407573529996955224135760342 422259061068512044369`
+        // P-256 `n` is defined as
+        // `115792089210356248762697446949407573529996955224135760342
+        // 422259061068512044369`
         const N: Lazy<BigInt> = Lazy::new(|| {
             BigInt::from_str(
                 "115792089210356248762697446949407573529996955224135760342422259061068512044369",
@@ -182,8 +186,8 @@ impl Group for ProjectivePoint {
 /// Corresponds to the hash_to_curve_simple_swu() function defined in
 /// <https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-hash-to-curve-11#appendix-F.2>
 ///
-/// `cmov`, `mod_floor` and `modpow` needs to be made constant-time, which
-/// will be supported after crypto-bigint is no longer experimental. See
+/// `cmov`, `mod_floor` and `modpow` needs to be made constant-time, which will
+/// be supported after crypto-bigint is no longer experimental. See
 /// <https://github.com/novifinancial/voprf/issues/13> for more context.
 
 #[allow(clippy::many_single_char_names)]
@@ -435,9 +439,10 @@ fn hash_to_curve_simple_swu<N: ArrayLength<u8>>(
 
 #[cfg(test)]
 mod tests {
-    use super::*;
     use generic_array::typenum::U96;
 
+    use super::*;
+
     struct Params {
         msg: &'static str,
         px: &'static str,

src/group/ristretto.rs

@@ -22,8 +22,8 @@ use generic_array::{
 };
 use rand_core::{CryptoRng, RngCore};
 
-// `cfg` here is only needed because of a bug in Rust's crate feature documentation.
-// See: https://github.com/rust-lang/rust/issues/83428
+// `cfg` here is only needed because of a bug in Rust's crate feature documentation. See:
+// https://github.com/rust-lang/rust/issues/83428
 cfg_ristretto! {
     /// The implementation of such a subgroup for Ristretto
     impl Group for RistrettoPoint {

src/group/tests.rs

@@ -10,8 +10,8 @@
 use crate::errors::InternalError;
 use crate::group::Group;
 
-// Test that the deserialization of a group element should throw an error
-// if the identity element can be deserialized properly
+// Test that the deserialization of a group element should throw an error if the
+// identity element can be deserialized properly
 
 #[test]
 fn test_group_properties() -> Result<(), InternalError> {