Expose `orchard::note_encryption::{CompactAction, OrchardNoteEncryption}`

This also removes the `orchard::OrchardDomain` re-export, which is now
available at `orchard::note_encryption::OrchardDomain`.

src/lib.rs

@@ -23,7 +23,7 @@ pub mod circuit;
 mod constants;
 pub mod keys;
 pub mod note;
-mod note_encryption;
+pub mod note_encryption;
 pub mod primitives;
 mod spec;
 pub mod tree;
@@ -36,5 +36,4 @@ pub use address::Address;
 pub use bundle::Bundle;
 pub use circuit::Proof;
 pub use note::Note;
-pub use note_encryption::OrchardDomain;
 pub use tree::Anchor;

src/note_encryption.rs

@@ -1,6 +1,6 @@
 //! In-band secret distribution for Orchard bundles.
 
-use std::convert::TryInto;
+use std::{convert::TryInto, fmt};
 
 use blake2b_simd::{Hash, Params};
 use halo2::arithmetic::FieldExt;
@@ -242,6 +242,7 @@ impl Domain for OrchardDomain {
     }
 }
 
+/// Implementation of in-band secret distribution for Orchard bundles.
 pub type OrchardNoteEncryption = zcash_note_encryption::NoteEncryption<OrchardDomain>;
 
 impl<T> ShieldedOutput<OrchardDomain> for Action<T> {
@@ -258,12 +259,19 @@ impl<T> ShieldedOutput<OrchardDomain> for Action<T> {
     }
 }
 
-struct CompactAction {
+/// A compact Action for light clients.
+pub struct CompactAction {
     ephemeral_key: EphemeralKeyBytes,
     cmx: ExtractedNoteCommitment,
     enc_ciphertext: [u8; 52],
 }
 
+impl fmt::Debug for CompactAction {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "CompactAction")
+    }
+}
+
 impl<T> From<&Action<T>> for CompactAction {
     fn from(action: &Action<T>) -> Self {
         CompactAction {