From e82cf0f5a8b6771583e93fa79ed41bee7050687d Mon Sep 17 00:00:00 2001
From: Deirdre Connolly <deirdre@zfnd.org>
Date: Fri, 31 Jan 2020 21:09:46 -0500
Subject: [PATCH] Add BlockHeaderHash (de)serialization roundtrip proptest

---
 zebra-chain/src/block.rs | 24 +++++++++++++++++++++++-
 zebra-chain/src/types.rs |  1 -
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/zebra-chain/src/block.rs b/zebra-chain/src/block.rs
index 86326a7fa..fab67517e 100644
--- a/zebra-chain/src/block.rs
+++ b/zebra-chain/src/block.rs
@@ -11,6 +11,9 @@ use std::{
     io::{self, Read},
 };
 
+#[cfg(test)]
+use proptest_derive::Arbitrary;
+
 use crate::merkle_tree::MerkleTreeRootHash;
 use crate::note_commitment_tree::SaplingNoteTreeRootHash;
 use crate::serialization::{
@@ -32,6 +35,7 @@ use crate::transaction::Transaction;
 /// for now I want to call it a `BlockHeaderHash` because that's
 /// more explicit.
 #[derive(Copy, Clone, Eq, PartialEq)]
+#[cfg_attr(test, derive(Arbitrary))]
 pub struct BlockHeaderHash(pub [u8; 32]);
 
 impl fmt::Debug for BlockHeaderHash {
@@ -184,8 +188,10 @@ impl ZcashDeserialize for Block {
 #[cfg(test)]
 mod tests {
 
+    use std::io::{Cursor, Write};
+
     use chrono::NaiveDateTime;
-    use std::io::Write;
+    use proptest::prelude::*;
 
     use crate::sha256d_writer::Sha256dWriter;
 
@@ -226,4 +232,20 @@ mod tests {
             "BlockHeaderHash(\"35be4a0f97803879ed642d4e10a146c3fba8727a1dca8079e3f107221be1e7e4\")"
         );
     }
+
+    proptest! {
+
+        #[test]
+        fn blockheaderhash_roundtrip(hash in any::<BlockHeaderHash>()) {
+            let mut bytes = Cursor::new(Vec::new());
+            hash.zcash_serialize(&mut bytes)?;
+
+            bytes.set_position(0);
+            let other_hash = BlockHeaderHash::zcash_deserialize(&mut bytes)?;
+
+            prop_assert_eq![hash, other_hash];
+        }
+
+
+    }
 }
diff --git a/zebra-chain/src/types.rs b/zebra-chain/src/types.rs
index af56c88cd..9c3523014 100644
--- a/zebra-chain/src/types.rs
+++ b/zebra-chain/src/types.rs
@@ -183,6 +183,5 @@ mod proptests {
             prop_assert_eq![script, other_script];
         }
 
-
     }
 }