Use doc_auto_cfg (#618)

Generate feature-dependent rustdoc automatically rather than through
manual annotations

ecdsa/src/der.rs

@@ -222,7 +222,6 @@ where
 }
 
 #[cfg(feature = "alloc")]
-#[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
 impl<C> From<Signature<C>> for Box<[u8]>
 where
     C: PrimeCurve,
@@ -235,7 +234,6 @@ where
 }
 
 #[cfg(feature = "alloc")]
-#[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
 impl<C> SignatureEncoding for Signature<C>
 where
     C: PrimeCurve,
@@ -250,7 +248,6 @@ where
 }
 
 #[cfg(feature = "serde")]
-#[cfg_attr(docsrs, doc(cfg(feature = "serde")))]
 impl<C> Serialize for Signature<C>
 where
     C: PrimeCurve,
@@ -266,7 +263,6 @@ where
 }
 
 #[cfg(feature = "serde")]
-#[cfg_attr(docsrs, doc(cfg(feature = "serde")))]
 impl<'de, C> Deserialize<'de> for Signature<C>
 where
     C: PrimeCurve,

ecdsa/src/dev.rs

@@ -29,7 +29,6 @@ pub struct TestVector {
 
 /// Define ECDSA signing test.
 #[macro_export]
-#[cfg_attr(docsrs, doc(cfg(feature = "dev")))]
 macro_rules! new_signing_test {
     ($curve:path, $vectors:expr) => {
         use $crate::{
@@ -65,7 +64,6 @@ macro_rules! new_signing_test {
 
 /// Define ECDSA verification test.
 #[macro_export]
-#[cfg_attr(docsrs, doc(cfg(feature = "dev")))]
 macro_rules! new_verification_test {
     ($curve:path, $vectors:expr) => {
         use $crate::{
@@ -133,7 +131,6 @@ macro_rules! new_verification_test {
 
 /// Define a Wycheproof verification test.
 #[macro_export]
-#[cfg_attr(docsrs, doc(cfg(feature = "dev")))]
 macro_rules! new_wycheproof_test {
     ($name:ident, $test_name: expr, $curve:path) => {
         use $crate::{elliptic_curve::sec1::EncodedPoint, signature::Verifier, Signature};

ecdsa/src/hazmat.rs

@@ -50,7 +50,6 @@ use elliptic_curve::ScalarCore;
 /// This trait is intended to be implemented on a type with access to the
 /// secret scalar via `&self`, such as particular curve's `Scalar` type.
 #[cfg(feature = "arithmetic")]
-#[cfg_attr(docsrs, doc(cfg(feature = "arithmetic")))]
 pub trait SignPrimitive<C>: Field + Into<FieldBytes<C>> + Reduce<C::UInt> + Sized
 where
     C: PrimeCurve + ProjectiveArithmetic + ScalarArithmetic<Scalar = Self>,
@@ -113,7 +112,6 @@ where
     ///
     /// [RFC6979]: https://datatracker.ietf.org/doc/html/rfc6979
     #[cfg(all(feature = "rfc6979"))]
-    #[cfg_attr(docsrs, doc(cfg(feature = "rfc6979")))]
     fn try_sign_prehashed_rfc6979<D>(
         &self,
         z: FieldBytes<C>,
@@ -135,7 +133,6 @@ where
     ///
     /// [RFC6979]: https://datatracker.ietf.org/doc/html/rfc6979
     #[cfg(all(feature = "rfc6979"))]
-    #[cfg_attr(docsrs, doc(cfg(feature = "rfc6979")))]
     fn try_sign_digest_rfc6979<D>(
         &self,
         msg_digest: D,
@@ -156,7 +153,6 @@ where
 /// the affine point represeting the public key via `&self`, such as a
 /// particular curve's `AffinePoint` type.
 #[cfg(feature = "arithmetic")]
-#[cfg_attr(docsrs, doc(cfg(feature = "arithmetic")))]
 pub trait VerifyPrimitive<C>: AffineXCoordinate<C> + Copy + Sized
 where
     C: PrimeCurve + AffineArithmetic<AffinePoint = Self> + ProjectiveArithmetic,
@@ -194,7 +190,6 @@ where
 
     /// Verify message digest against the provided signature.
     #[cfg(feature = "digest")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "digest")))]
     fn verify_digest<D>(&self, msg_digest: D, sig: &Signature<C>) -> Result<()>
     where
         D: FixedOutput<OutputSize = FieldSize<C>>,
@@ -214,7 +209,6 @@ where
 ///
 /// [1]: https://github.com/RustCrypto/traits/tree/master/signature/derive
 #[cfg(feature = "digest")]
-#[cfg_attr(docsrs, doc(cfg(feature = "digest")))]
 pub trait DigestPrimitive: PrimeCurve {
     /// Preferred digest to use when computing ECDSA signatures for this
     /// elliptic curve. This is typically a member of the SHA-2 family.

ecdsa/src/lib.rs

@@ -1,5 +1,5 @@
 #![no_std]
-#![cfg_attr(docsrs, feature(doc_cfg))]
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
 #![doc = include_str!("../README.md")]
 #![doc(
     html_logo_url = "https://raw.githubusercontent.com/RustCrypto/media/8f1a9894/logo.svg",
@@ -60,20 +60,13 @@ extern crate alloc;
 mod recovery;
 
 #[cfg(feature = "der")]
-#[cfg_attr(docsrs, doc(cfg(feature = "der")))]
 pub mod der;
-
 #[cfg(feature = "dev")]
-#[cfg_attr(docsrs, doc(cfg(feature = "dev")))]
 pub mod dev;
-
 #[cfg(feature = "hazmat")]
-#[cfg_attr(docsrs, doc(cfg(feature = "hazmat")))]
 pub mod hazmat;
-
 #[cfg(feature = "signing")]
 mod signing;
-
 #[cfg(feature = "verifying")]
 mod verifying;
 
@@ -86,11 +79,8 @@ pub use elliptic_curve::{self, sec1::EncodedPoint, PrimeCurve};
 pub use signature::{self, Error, Result, SignatureEncoding};
 
 #[cfg(feature = "signing")]
-#[cfg_attr(docsrs, doc(cfg(feature = "signing")))]
 pub use crate::signing::SigningKey;
-
 #[cfg(feature = "verifying")]
-#[cfg_attr(docsrs, doc(cfg(feature = "verifying")))]
 pub use crate::verifying::VerifyingKey;
 
 use core::{
@@ -156,7 +146,6 @@ where
 {
     /// Parse a signature from ASN.1 DER
     #[cfg(feature = "der")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "der")))]
     pub fn from_der(bytes: &[u8]) -> Result<Self>
     where
         der::MaxSize<C>: ArrayLength<u8>,
@@ -187,7 +176,6 @@ where
 
     /// Serialize this signature as ASN.1 DER.
     #[cfg(feature = "der")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "der")))]
     pub fn to_der(&self) -> der::Signature<C>
     where
         der::MaxSize<C>: ArrayLength<u8>,
@@ -199,14 +187,12 @@ where
 
     /// Convert this signature into a byte vector.
     #[cfg(feature = "alloc")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
     pub fn to_vec(&self) -> Vec<u8> {
         self.to_bytes().to_vec()
     }
 }
 
 #[cfg(feature = "arithmetic")]
-#[cfg_attr(docsrs, doc(cfg(feature = "arithmetic")))]
 impl<C> Signature<C>
 where
     C: PrimeCurve + ScalarArithmetic,
@@ -347,7 +333,6 @@ where
 }
 
 #[cfg(feature = "arithmetic")]
-#[cfg_attr(docsrs, doc(cfg(feature = "arithmetic")))]
 impl<C> str::FromStr for Signature<C>
 where
     C: PrimeCurve + ScalarArithmetic,
@@ -384,7 +369,6 @@ where
 }
 
 #[cfg(feature = "serde")]
-#[cfg_attr(docsrs, doc(cfg(feature = "serde")))]
 impl<C> Serialize for Signature<C>
 where
     C: PrimeCurve,
@@ -399,7 +383,6 @@ where
 }
 
 #[cfg(feature = "serde")]
-#[cfg_attr(docsrs, doc(cfg(feature = "serde")))]
 impl<'de, C> Deserialize<'de> for Signature<C>
 where
     C: PrimeCurve,

ecdsa/src/recovery.rs

@@ -72,7 +72,6 @@ impl RecoveryId {
 }
 
 #[cfg(feature = "verifying")]
-#[cfg_attr(docsrs, doc(cfg(feature = "verifying")))]
 impl RecoveryId {
     /// Given a public key, message, and signature, use trial recovery
     /// to determine if a suitable recovery ID exists, or return an error
@@ -158,7 +157,6 @@ impl From<RecoveryId> for u8 {
 }
 
 #[cfg(feature = "verifying")]
-#[cfg_attr(docsrs, doc(cfg(feature = "verifying")))]
 impl<C> VerifyingKey<C>
 where
     C: PrimeCurve + ProjectiveArithmetic,

ecdsa/src/signing.rs

@@ -1,6 +1,4 @@
-//! ECDSA signing key.
-
-// TODO(tarcieri): support for hardware crypto accelerators
+//! ECDSA signing: producing signatures using a [`SigningKey`].
 
 use crate::{
     hazmat::{bits2field, DigestPrimitive, SignPrimitive},
@@ -46,7 +44,6 @@ use {crate::VerifyingKey, elliptic_curve::PublicKey, signature::KeypairRef};
 /// Requires an [`elliptic_curve::ProjectiveArithmetic`] impl on the curve, and a
 /// [`SignPrimitive`] impl on its associated `Scalar` type.
 #[derive(Clone)]
-#[cfg_attr(docsrs, doc(cfg(feature = "signing")))]
 pub struct SigningKey<C>
 where
     C: PrimeCurve + ProjectiveArithmetic,
@@ -97,7 +94,6 @@ where
 
     /// Get the [`VerifyingKey`] which corresponds to this [`SigningKey`].
     #[cfg(feature = "verifying")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "verifying")))]
     pub fn verifying_key(&self) -> &VerifyingKey<C> {
         &self.verifying_key
     }
@@ -196,7 +192,6 @@ where
 }
 
 #[cfg(feature = "der")]
-#[cfg_attr(docsrs, doc(cfg(feature = "der")))]
 impl<C> PrehashSigner<der::Signature<C>> for SigningKey<C>
 where
     C: PrimeCurve + ProjectiveArithmetic + DigestPrimitive,
@@ -213,7 +208,6 @@ where
 }
 
 #[cfg(feature = "der")]
-#[cfg_attr(docsrs, doc(cfg(feature = "der")))]
 impl<C> Signer<der::Signature<C>> for SigningKey<C>
 where
     Self: DigestSigner<C::Digest, Signature<C>>,
@@ -229,7 +223,6 @@ where
 }
 
 #[cfg(feature = "der")]
-#[cfg_attr(docsrs, doc(cfg(feature = "der")))]
 impl<C, D> RandomizedDigestSigner<D, der::Signature<C>> for SigningKey<C>
 where
     C: PrimeCurve + ProjectiveArithmetic,
@@ -251,7 +244,6 @@ where
 }
 
 #[cfg(feature = "der")]
-#[cfg_attr(docsrs, doc(cfg(feature = "der")))]
 impl<C> RandomizedSigner<der::Signature<C>> for SigningKey<C>
 where
     Self: RandomizedDigestSigner<C::Digest, Signature<C>>,
@@ -275,7 +267,6 @@ where
 //
 
 #[cfg(feature = "verifying")]
-#[cfg_attr(docsrs, doc(cfg(feature = "verifying")))]
 impl<C> AsRef<VerifyingKey<C>> for SigningKey<C>
 where
     C: PrimeCurve + ProjectiveArithmetic,
@@ -449,7 +440,6 @@ where
 }
 
 #[cfg(feature = "verifying")]
-#[cfg_attr(docsrs, doc(cfg(feature = "verifying")))]
 impl<C> KeypairRef for SigningKey<C>
 where
     C: PrimeCurve + ProjectiveArithmetic,
@@ -460,7 +450,6 @@ where
 }
 
 #[cfg(feature = "pkcs8")]
-#[cfg_attr(docsrs, doc(cfg(feature = "pkcs8")))]
 impl<C> TryFrom<pkcs8::PrivateKeyInfo<'_>> for SigningKey<C>
 where
     C: PrimeCurve + AssociatedOid + ProjectiveArithmetic,
@@ -477,7 +466,6 @@ where
 }
 
 #[cfg(feature = "pem")]
-#[cfg_attr(docsrs, doc(cfg(feature = "pem")))]
 impl<C> EncodePrivateKey for SigningKey<C>
 where
     C: AssociatedOid + PrimeCurve + ProjectiveArithmetic,
@@ -492,7 +480,6 @@ where
 }
 
 #[cfg(feature = "pem")]
-#[cfg_attr(docsrs, doc(cfg(feature = "pem")))]
 impl<C> FromStr for SigningKey<C>
 where
     C: PrimeCurve + AssociatedOid + ProjectiveArithmetic,
@@ -509,7 +496,6 @@ where
 }
 
 #[cfg(feature = "pkcs8")]
-#[cfg_attr(docsrs, doc(cfg(feature = "pkcs8")))]
 impl<C> DecodePrivateKey for SigningKey<C>
 where
     C: PrimeCurve + AssociatedOid + ProjectiveArithmetic,

ecdsa/src/verifying.rs

@@ -1,4 +1,4 @@
-//! ECDSA verification key.
+//! ECDSA verifying: checking signatures are authentic using a [`VerifyingKey`].
 
 use crate::{
     hazmat::{bits2field, DigestPrimitive, VerifyPrimitive},
@@ -30,7 +30,6 @@ use elliptic_curve::pkcs8::EncodePublicKey;
 use core::str::FromStr;
 
 #[cfg(all(feature = "pem", feature = "serde"))]
-#[cfg_attr(docsrs, doc(cfg(all(feature = "pem", feature = "serde"))))]
 use serdect::serde::{de, ser, Deserialize, Serialize};
 
 /// ECDSA verification key (i.e. public key). Generic over elliptic curves.
@@ -46,7 +45,6 @@ use serdect::serde::{de, ser, Deserialize, Serialize};
 ///
 /// The serialization leverages the encoding used by the [`PublicKey`] type,
 /// which is a binary-oriented ASN.1 DER encoding.
-#[cfg_attr(docsrs, doc(cfg(feature = "verifying")))]
 #[derive(Clone, Debug)]
 pub struct VerifyingKey<C>
 where
@@ -141,7 +139,6 @@ where
 }
 
 #[cfg(feature = "der")]
-#[cfg_attr(docsrs, doc(cfg(feature = "der")))]
 impl<C, D> DigestVerifier<D, der::Signature<C>> for VerifyingKey<C>
 where
     C: PrimeCurve + ProjectiveArithmetic,
@@ -159,7 +156,6 @@ where
 }
 
 #[cfg(feature = "der")]
-#[cfg_attr(docsrs, doc(cfg(feature = "der")))]
 impl<C> PrehashVerifier<der::Signature<C>> for VerifyingKey<C>
 where
     C: PrimeCurve + ProjectiveArithmetic + DigestPrimitive,
@@ -176,7 +172,6 @@ where
 }
 
 #[cfg(feature = "der")]
-#[cfg_attr(docsrs, doc(cfg(feature = "der")))]
 impl<C> Verifier<der::Signature<C>> for VerifyingKey<C>
 where
     C: PrimeCurve + ProjectiveArithmetic + DigestPrimitive,
@@ -304,7 +299,6 @@ where
 }
 
 #[cfg(feature = "pkcs8")]
-#[cfg_attr(docsrs, doc(cfg(feature = "pkcs8")))]
 impl<C> TryFrom<pkcs8::SubjectPublicKeyInfo<'_>> for VerifyingKey<C>
 where
     C: PrimeCurve + AssociatedOid + ProjectiveArithmetic + PointCompression,
@@ -319,7 +313,6 @@ where
 }
 
 #[cfg(feature = "pkcs8")]
-#[cfg_attr(docsrs, doc(cfg(feature = "pkcs8")))]
 impl<C> DecodePublicKey for VerifyingKey<C>
 where
     C: PrimeCurve + AssociatedOid + ProjectiveArithmetic + PointCompression,
@@ -329,7 +322,6 @@ where
 }
 
 #[cfg(feature = "pem")]
-#[cfg_attr(docsrs, doc(cfg(feature = "pem")))]
 impl<C> EncodePublicKey for VerifyingKey<C>
 where
     C: PrimeCurve + AssociatedOid + ProjectiveArithmetic + PointCompression,
@@ -342,7 +334,6 @@ where
 }
 
 #[cfg(feature = "pem")]
-#[cfg_attr(docsrs, doc(cfg(feature = "pem")))]
 impl<C> FromStr for VerifyingKey<C>
 where
     C: PrimeCurve + AssociatedOid + ProjectiveArithmetic + PointCompression,
@@ -357,7 +348,6 @@ where
 }
 
 #[cfg(all(feature = "pem", feature = "serde"))]
-#[cfg_attr(docsrs, doc(cfg(all(feature = "pem", feature = "serde"))))]
 impl<C> Serialize for VerifyingKey<C>
 where
     C: PrimeCurve + AssociatedOid + ProjectiveArithmetic + PointCompression,
@@ -373,7 +363,6 @@ where
 }
 
 #[cfg(all(feature = "pem", feature = "serde"))]
-#[cfg_attr(docsrs, doc(cfg(all(feature = "pem", feature = "serde"))))]
 impl<'de, C> Deserialize<'de> for VerifyingKey<C>
 where
     C: PrimeCurve + AssociatedOid + ProjectiveArithmetic + PointCompression,

ed25519/src/lib.rs

@@ -1,5 +1,5 @@
 #![no_std]
-#![cfg_attr(docsrs, feature(doc_cfg))]
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
 #![doc = include_str!("../README.md")]
 #![doc(html_logo_url = "https://raw.githubusercontent.com/RustCrypto/meta/master/logo_small.png")]
 #![allow(non_snake_case)]
@@ -261,7 +261,6 @@
 extern crate alloc;
 
 #[cfg(feature = "pkcs8")]
-#[cfg_attr(docsrs, doc(cfg(feature = "pkcs8")))]
 pub mod pkcs8;
 
 #[cfg(feature = "serde")]
@@ -347,7 +346,6 @@ impl Signature {
 
     /// Convert this signature into a byte vector.
     #[cfg(feature = "alloc")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
     pub fn to_vec(&self) -> Vec<u8> {
         self.to_bytes().to_vec()
     }

ed25519/src/pkcs8.rs

@@ -121,7 +121,6 @@ impl Drop for KeypairBytes {
 }
 
 #[cfg(feature = "alloc")]
-#[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
 impl EncodePrivateKey for KeypairBytes {
     fn to_pkcs8_der(&self) -> Result<SecretDocument> {
         // Serialize private key as nested OCTET STRING
@@ -198,7 +197,6 @@ impl fmt::Debug for KeypairBytes {
 }
 
 #[cfg(feature = "pem")]
-#[cfg_attr(docsrs, doc(cfg(feature = "pem")))]
 impl str::FromStr for KeypairBytes {
     type Err = Error;
 
@@ -245,7 +243,6 @@ impl AsRef<[u8; Self::BYTE_SIZE]> for PublicKeyBytes {
 impl DecodePublicKey for PublicKeyBytes {}
 
 #[cfg(feature = "alloc")]
-#[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
 impl EncodePublicKey for PublicKeyBytes {
     fn to_public_key_der(&self) -> pkcs8::spki::Result<Document> {
         pkcs8::SubjectPublicKeyInfo {
@@ -310,7 +307,6 @@ impl fmt::Debug for PublicKeyBytes {
 }
 
 #[cfg(feature = "pem")]
-#[cfg_attr(docsrs, doc(cfg(feature = "pem")))]
 impl str::FromStr for PublicKeyBytes {
     type Err = pkcs8::spki::Error;
 
@@ -320,7 +316,6 @@ impl str::FromStr for PublicKeyBytes {
 }
 
 #[cfg(feature = "pem")]
-#[cfg_attr(docsrs, doc(cfg(feature = "pem")))]
 impl ToString for PublicKeyBytes {
     fn to_string(&self) -> String {
         self.to_public_key_pem(Default::default())
@@ -329,7 +324,6 @@ impl ToString for PublicKeyBytes {
 }
 
 #[cfg(feature = "pem")]
-#[cfg_attr(docsrs, doc(cfg(feature = "pem")))]
 #[cfg(test)]
 mod tests {
     use super::{KeypairBytes, PublicKeyBytes};

ed25519/src/serde.rs

@@ -7,7 +7,6 @@ use core::fmt;
 #[cfg(feature = "serde_bytes")]
 use serde_bytes_crate as serde_bytes;
 
-#[cfg_attr(docsrs, doc(cfg(feature = "serde")))]
 impl Serialize for Signature {
     fn serialize<S: ser::Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
         use ser::SerializeTuple;
@@ -24,7 +23,6 @@ impl Serialize for Signature {
 
 // serde lacks support for deserializing arrays larger than 32-bytes
 // see: <https://github.com/serde-rs/serde/issues/631>
-#[cfg_attr(docsrs, doc(cfg(feature = "serde")))]
 impl<'de> Deserialize<'de> for Signature {
     fn deserialize<D: de::Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
         struct ByteArrayVisitor;
@@ -59,7 +57,6 @@ impl<'de> Deserialize<'de> for Signature {
 }
 
 #[cfg(feature = "serde_bytes")]
-#[cfg_attr(docsrs, doc(cfg(feature = "serde_bytes")))]
 impl serde_bytes::Serialize for Signature {
     fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
     where
@@ -70,7 +67,6 @@ impl serde_bytes::Serialize for Signature {
 }
 
 #[cfg(feature = "serde_bytes")]
-#[cfg_attr(docsrs, doc(cfg(feature = "serde_bytes")))]
 impl<'de> serde_bytes::Deserialize<'de> for Signature {
     fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
     where

rfc6979/Cargo.toml

@@ -21,7 +21,3 @@ zeroize = { version = "1", default-features = false }
 
 [dev-dependencies]
 sha2 = "0.10"
-
-[package.metadata.docs.rs]
-all-features = true
-rustdoc-args = ["--cfg", "docsrs"]

rfc6979/src/lib.rs

@@ -1,4 +1,11 @@
+#![no_std]
 #![doc = include_str!("../README.md")]
+#![forbid(unsafe_code, clippy::unwrap_used)]
+#![warn(missing_docs, rust_2018_idioms)]
+#![doc(
+    html_logo_url = "https://raw.githubusercontent.com/RustCrypto/media/8f1a9894/logo.svg",
+    html_favicon_url = "https://raw.githubusercontent.com/RustCrypto/media/8f1a9894/logo.svg"
+)]
 
 //! ## Usage
 //!
@@ -29,15 +36,6 @@
 //! assert_eq!(&k.to_be_byte_array(), &RFC6979_EXPECTED_K.to_be_byte_array());
 //! ```
 
-#![no_std]
-#![cfg_attr(docsrs, feature(doc_cfg))]
-#![forbid(unsafe_code, clippy::unwrap_used)]
-#![warn(missing_docs, rust_2018_idioms)]
-#![doc(
-    html_logo_url = "https://raw.githubusercontent.com/RustCrypto/media/8f1a9894/logo.svg",
-    html_favicon_url = "https://raw.githubusercontent.com/RustCrypto/media/8f1a9894/logo.svg"
-)]
-
 use crypto_bigint::{ArrayEncoding, ByteArray, Integer};
 use hmac::{
     digest::{