Use doc_auto_cfg and remove manual doc(cfg()) gates

Also remove now-duplicated comments about what features
an item requires.

src/crl.rs

@@ -57,7 +57,6 @@ pub trait CertRevocationList: Sealed + Debug {
 ///
 /// [^1]: <https://www.rfc-editor.org/rfc/rfc5280#section-5>
 #[cfg(feature = "alloc")]
-#[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
 #[derive(Debug, Clone)]
 pub struct OwnedCertRevocationList {
     /// A map of the revoked certificates contained in then CRL, keyed by the DER encoding
@@ -144,7 +143,6 @@ impl<'a> BorrowedCertRevocationList<'a> {
     /// Convert the CRL to an [`OwnedCertRevocationList`]. This may error if any of the revoked
     /// certificates in the CRL are malformed or contain unsupported features.
     #[cfg(feature = "alloc")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
     pub fn to_owned(&self) -> Result<OwnedCertRevocationList, Error> {
         // Parse and collect the CRL's revoked cert entries, ensuring there are no errors. With
         // the full set in-hand, create a lookup map by serial number for fast revocation checking.
@@ -452,7 +450,6 @@ pub struct BorrowedRevokedCert<'a> {
 impl<'a> BorrowedRevokedCert<'a> {
     /// Construct an owned representation of the revoked certificate.
     #[cfg(feature = "alloc")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
     pub fn to_owned(&self) -> OwnedRevokedCert {
         OwnedRevokedCert {
             serial_number: self.serial_number.to_vec(),

src/end_entity.rs

@@ -159,7 +159,6 @@ impl<'a> EndEntityCert<'a> {
     /// Verification functions are already provided as `verify_is_valid_for_dns_name`
     /// and `verify_is_valid_for_at_least_one_dns_name`.
     #[cfg(feature = "alloc")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
     pub fn dns_names(&'a self) -> Result<impl Iterator<Item = GeneralDnsNameRef<'a>>, Error> {
         subject_name::list_cert_dns_names(self)
     }

src/error.rs

@@ -248,7 +248,6 @@ impl fmt::Display for Error {
 }
 
 #[cfg(feature = "std")]
-#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
 impl ::std::error::Error for Error {}
 
 impl From<untrusted::EndOfInput> for Error {

src/lib.rs

@@ -37,7 +37,7 @@
     clippy::upper_case_acronyms
 )]
 // Enable documentation for all features on docs.rs
-#![cfg_attr(docsrs, feature(doc_cfg))]
+#![cfg_attr(docsrs, feature(doc_cfg, doc_auto_cfg))]
 
 #[cfg(any(test, feature = "alloc"))]
 #[cfg_attr(test, macro_use)]
@@ -78,20 +78,17 @@ pub use {
     },
 };
 
-#[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
 #[cfg(feature = "alloc")]
 pub use {
     crl::{OwnedCertRevocationList, OwnedRevokedCert},
     subject_name::{DnsName, IpAddr},
 };
 
-#[cfg_attr(docsrs, doc(cfg(feature = "ring")))]
 #[cfg(feature = "ring")]
 pub use ring_algs::{
     ECDSA_P256_SHA256, ECDSA_P256_SHA384, ECDSA_P384_SHA256, ECDSA_P384_SHA384, ED25519,
 };
 
-#[cfg_attr(docsrs, doc(cfg(all(feature = "ring", feature = "alloc"))))]
 #[cfg(all(feature = "ring", feature = "alloc"))]
 pub use ring_algs::{
     RSA_PKCS1_2048_8192_SHA256, RSA_PKCS1_2048_8192_SHA384, RSA_PKCS1_2048_8192_SHA512,

src/ring_algs.rs

@@ -72,8 +72,6 @@ pub static ECDSA_P384_SHA384: &dyn SignatureVerificationAlgorithm = &RingAlgorit
 };
 
 /// RSA PKCS#1 1.5 signatures using SHA-256 for keys of 2048-8192 bits.
-///
-/// Requires the `alloc` feature.
 #[cfg(feature = "alloc")]
 pub static RSA_PKCS1_2048_8192_SHA256: &dyn SignatureVerificationAlgorithm = &RingAlgorithm {
     public_key_alg_id: alg_id::RSA_ENCRYPTION,
@@ -82,8 +80,6 @@ pub static RSA_PKCS1_2048_8192_SHA256: &dyn SignatureVerificationAlgorithm = &Ri
 };
 
 /// RSA PKCS#1 1.5 signatures using SHA-384 for keys of 2048-8192 bits.
-///
-/// Requires the `alloc` feature.
 #[cfg(feature = "alloc")]
 pub static RSA_PKCS1_2048_8192_SHA384: &dyn SignatureVerificationAlgorithm = &RingAlgorithm {
     public_key_alg_id: alg_id::RSA_ENCRYPTION,
@@ -92,8 +88,6 @@ pub static RSA_PKCS1_2048_8192_SHA384: &dyn SignatureVerificationAlgorithm = &Ri
 };
 
 /// RSA PKCS#1 1.5 signatures using SHA-512 for keys of 2048-8192 bits.
-///
-/// Requires the `alloc` feature.
 #[cfg(feature = "alloc")]
 pub static RSA_PKCS1_2048_8192_SHA512: &dyn SignatureVerificationAlgorithm = &RingAlgorithm {
     public_key_alg_id: alg_id::RSA_ENCRYPTION,
@@ -102,8 +96,6 @@ pub static RSA_PKCS1_2048_8192_SHA512: &dyn SignatureVerificationAlgorithm = &Ri
 };
 
 /// RSA PKCS#1 1.5 signatures using SHA-384 for keys of 3072-8192 bits.
-///
-/// Requires the `alloc` feature.
 #[cfg(feature = "alloc")]
 pub static RSA_PKCS1_3072_8192_SHA384: &dyn SignatureVerificationAlgorithm = &RingAlgorithm {
     public_key_alg_id: alg_id::RSA_ENCRYPTION,
@@ -115,8 +107,6 @@ pub static RSA_PKCS1_3072_8192_SHA384: &dyn SignatureVerificationAlgorithm = &Ri
 /// type rsaEncryption; see [RFC 4055 Section 1.2].
 ///
 /// [RFC 4055 Section 1.2]: https://tools.ietf.org/html/rfc4055#section-1.2
-///
-/// Requires the `alloc` feature.
 #[cfg(feature = "alloc")]
 pub static RSA_PSS_2048_8192_SHA256_LEGACY_KEY: &dyn SignatureVerificationAlgorithm =
     &RingAlgorithm {
@@ -129,8 +119,6 @@ pub static RSA_PSS_2048_8192_SHA256_LEGACY_KEY: &dyn SignatureVerificationAlgori
 /// type rsaEncryption; see [RFC 4055 Section 1.2].
 ///
 /// [RFC 4055 Section 1.2]: https://tools.ietf.org/html/rfc4055#section-1.2
-///
-/// Requires the `alloc` feature.
 #[cfg(feature = "alloc")]
 pub static RSA_PSS_2048_8192_SHA384_LEGACY_KEY: &dyn SignatureVerificationAlgorithm =
     &RingAlgorithm {
@@ -143,8 +131,6 @@ pub static RSA_PSS_2048_8192_SHA384_LEGACY_KEY: &dyn SignatureVerificationAlgori
 /// type rsaEncryption; see [RFC 4055 Section 1.2].
 ///
 /// [RFC 4055 Section 1.2]: https://tools.ietf.org/html/rfc4055#section-1.2
-///
-/// Requires the `alloc` feature.
 #[cfg(feature = "alloc")]
 pub static RSA_PSS_2048_8192_SHA512_LEGACY_KEY: &dyn SignatureVerificationAlgorithm =
     &RingAlgorithm {

src/signed_data.rs

@@ -21,7 +21,6 @@ use alloc::vec::Vec;
 /// X.509 certificates and related items that are signed are almost always
 /// encoded in the format "tbs||signatureAlgorithm||signature". This structure
 /// captures this pattern as an owned data type.
-#[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
 #[cfg(feature = "alloc")]
 #[derive(Clone, Debug)]
 pub(crate) struct OwnedSignedData {
@@ -132,7 +131,6 @@ impl<'a> SignedData<'a> {
 
     /// Convert the borrowed signed data to an [`OwnedSignedData`].
     #[cfg(feature = "alloc")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
     pub(crate) fn to_owned(&self) -> OwnedSignedData {
         OwnedSignedData {
             data: self.data.as_slice_less_safe().to_vec(),

src/subject_name/dns_name.rs

@@ -33,12 +33,10 @@ use crate::Error;
 ///
 /// Requires the `alloc` feature.
 #[cfg(feature = "alloc")]
-#[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
 #[derive(Clone, Debug, Eq, PartialEq, Hash)]
 pub struct DnsName(String);
 
 #[cfg(feature = "alloc")]
-#[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
 impl DnsName {
     /// Returns a `DnsNameRef` that refers to this `DnsName`.
     pub fn as_ref(&self) -> DnsNameRef {
@@ -47,7 +45,6 @@ impl DnsName {
 }
 
 #[cfg(feature = "alloc")]
-#[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
 impl AsRef<str> for DnsName {
     fn as_ref(&self) -> &str {
         self.0.as_ref()
@@ -87,7 +84,6 @@ impl core::fmt::Display for InvalidDnsNameError {
 }
 
 #[cfg(feature = "std")]
-#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
 impl ::std::error::Error for InvalidDnsNameError {}
 
 impl<'a> DnsNameRef<'a> {
@@ -113,7 +109,6 @@ impl<'a> DnsNameRef<'a> {
 
     /// Constructs a `DnsName` from this `DnsNameRef`
     #[cfg(feature = "alloc")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
     pub fn to_owned(&self) -> DnsName {
         // DnsNameRef is already guaranteed to be valid ASCII, which is a
         // subset of UTF-8.

src/subject_name/ip_address.rs

@@ -24,7 +24,6 @@ const VALID_IP_BY_CONSTRUCTION: &str = "IP address is a valid string by construc
 
 /// Either a IPv4 or IPv6 address, plus its owned string representation
 #[cfg(feature = "alloc")]
-#[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
 #[derive(Clone, Debug, Eq, PartialEq, Hash)]
 pub enum IpAddr {
     /// An IPv4 address and its owned string representation
@@ -34,7 +33,6 @@ pub enum IpAddr {
 }
 
 #[cfg(feature = "alloc")]
-#[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
 impl AsRef<str> for IpAddr {
     fn as_ref(&self) -> &str {
         match self {
@@ -53,7 +51,6 @@ pub enum IpAddrRef<'a> {
 }
 
 #[cfg(feature = "alloc")]
-#[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
 impl<'a> From<IpAddrRef<'a>> for IpAddr {
     fn from(ip_address: IpAddrRef<'a>) -> IpAddr {
         match ip_address {
@@ -70,7 +67,6 @@ impl<'a> From<IpAddrRef<'a>> for IpAddr {
 }
 
 #[cfg(feature = "alloc")]
-#[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
 impl<'a> From<&'a IpAddr> for IpAddrRef<'a> {
     fn from(ip_address: &'a IpAddr) -> IpAddrRef<'a> {
         match ip_address {
@@ -96,7 +92,6 @@ impl core::fmt::Display for AddrParseError {
 }
 
 #[cfg(feature = "std")]
-#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
 impl ::std::error::Error for AddrParseError {}
 
 impl<'a> IpAddrRef<'a> {
@@ -120,7 +115,6 @@ impl<'a> IpAddrRef<'a> {
 
     /// Constructs an `IpAddr` from this `IpAddrRef`
     #[cfg(feature = "alloc")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
     pub fn to_owned(&self) -> IpAddr {
         match self {
             IpAddrRef::V4(ip_address, ip_address_octets) => IpAddr::V4(
@@ -155,7 +149,6 @@ fn ipv6_to_uncompressed_string(octets: [u8; 16]) -> String {
 }
 
 #[cfg(feature = "std")]
-#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
 impl From<std::net::IpAddr> for IpAddr {
     fn from(ip_address: std::net::IpAddr) -> IpAddr {
         match ip_address {

src/time.rs

@@ -107,7 +107,6 @@ impl<'a> FromDer<'a> for Time {
 }
 
 #[cfg(feature = "std")]
-#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
 impl TryFrom<std::time::SystemTime> for Time {
     type Error = std::time::SystemTimeError;