Enable crate feature info in rustdocs

Cargo.toml

@@ -111,3 +111,7 @@ uuid = { version = "0.8", features = ["v4", "serde"] }
 difference = "2.0"
 did-method-key = { path = "./did-key" }
 tokio = { version = "1.0", features = ["macros"] }
+
+[package.metadata.docs.rs]
+features = ["secp256r1", "secp256k1", "ripemd-160", "http-did"]
+rustdoc-args = ["--cfg", "docsrs"]

src/hash.rs

@@ -1,20 +1,22 @@
 use crate::error::Error;
 
-#[cfg(feature = "sha2")]
+#[cfg(any(feature = "sha2", feature = "ring"))]
 pub fn sha256(data: &[u8]) -> Result<[u8; 32], Error> {
-    use sha2::Digest;
-    let mut hasher = sha2::Sha256::new();
-    hasher.update(data);
-    let hash = hasher.finalize().into();
-    Ok(hash)
-}
-
-#[cfg(feature = "ring")]
-pub fn sha256(data: &[u8]) -> Result<[u8; 32], Error> {
-    use ring::digest;
-    use std::convert::TryInto;
-    let hash = digest::digest(&digest::SHA256, data).as_ref().try_into()?;
-    Ok(hash)
+    #[cfg(feature = "sha2")]
+    {
+        use sha2::Digest;
+        let mut hasher = sha2::Sha256::new();
+        hasher.update(data);
+        let hash = hasher.finalize().into();
+        Ok(hash)
+    }
+    #[cfg(feature = "ring")]
+    {
+        use ring::digest;
+        use std::convert::TryInto;
+        let hash = digest::digest(&digest::SHA256, data).as_ref().try_into()?;
+        Ok(hash)
+    }
 }
 
 #[cfg(test)]

src/lib.rs

@@ -1,3 +1,5 @@
+#![cfg_attr(docsrs, feature(doc_cfg, doc_auto_cfg))]
+
 pub mod bbs;
 pub mod blakesig;
 pub mod caip10;