Add several Debug impls for existing types

Resolves #237

zebra-chain/src/merkle_tree.rs

@@ -1,7 +1,7 @@
 //! A binary hash tree of SHA256d (two rounds of SHA256) hashes for
 //! node values.
 
-use std::io;
+use std::{fmt, io};
 
 #[cfg(test)]
 use proptest_derive::Arbitrary;
@@ -31,7 +31,7 @@ impl<Transaction> ZcashDeserialize for MerkleTree<Transaction> {
 
 /// A SHA-256d hash of the root node of a merkle tree of SHA256-d
 /// hashed transactions in a block.
-#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+#[derive(Clone, Copy, Eq, PartialEq)]
 #[cfg_attr(test, derive(Arbitrary))]
 pub struct MerkleTreeRootHash(pub [u8; 32]);
 
@@ -44,3 +44,11 @@ impl From<MerkleTree<Transaction>> for MerkleTreeRootHash {
         Self(hash_writer.finish())
     }
 }
+
+impl fmt::Debug for MerkleTreeRootHash {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_tuple("MerkleTreeRootHash")
+            .field(&hex::encode(&self.0))
+            .finish()
+    }
+}

zebra-chain/src/note_commitment_tree.rs

@@ -10,7 +10,9 @@
 //!
 //! A root of a note commitment tree is associated with each treestate.
 
-use std::io;
+use std::{fmt, io};
+
+use hex;
 
 #[cfg(test)]
 use proptest_derive::Arbitrary;
@@ -31,10 +33,18 @@ pub struct SaplingNoteCommitmentTree;
 /// commitment tree corresponding to the final Sapling treestate of
 /// this block. A root of a note commitment tree is associated with
 /// each treestate.
-#[derive(Clone, Copy, Debug, Default, Eq, PartialEq)]
+#[derive(Clone, Copy, Default, Eq, PartialEq)]
 #[cfg_attr(test, derive(Arbitrary))]
 pub struct SaplingNoteTreeRootHash(pub [u8; 32]);
 
+impl fmt::Debug for SaplingNoteTreeRootHash {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_tuple("SaplingNoteTreeRootHash")
+            .field(&hex::encode(&self.0))
+            .finish()
+    }
+}
+
 impl From<SaplingNoteCommitmentTree> for SaplingNoteTreeRootHash {
     fn from(_tree: SaplingNoteCommitmentTree) -> Self {
         // TODO: The Sapling note commitment tree requires a Pedersen

zebra-chain/src/types.rs

@@ -101,10 +101,18 @@ impl Arbitrary for LockTime {
 }
 
 /// An encoding of a Bitcoin script.
-#[derive(Clone, Debug, Eq, PartialEq)]
+#[derive(Clone, Eq, PartialEq)]
 #[cfg_attr(test, derive(Arbitrary))]
 pub struct Script(pub Vec<u8>);
 
+impl fmt::Debug for Script {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_tuple("Script")
+            .field(&hex::encode(&self.0))
+            .finish()
+    }
+}
+
 impl ZcashSerialize for Script {
     fn zcash_serialize<W: io::Write>(&self, mut writer: W) -> Result<(), io::Error> {
         writer.write_compactsize(self.0.len() as u64)?;