fix: merkle tree algorithm

Author: samparsky

primitives/src/merkle_tree.rs

@@ -55,14 +55,19 @@ impl Algorithm<MerkleItem> for KeccakAlgorithm {
     fn node(&mut self, left: MerkleItem, right: MerkleItem, _height: usize) -> MerkleItem {
         let left_vec: Vec<u8> = left.to_vec();
         let right_vec: Vec<u8> = right.to_vec();
+        // This is a check for odd number of leaves items
+        // left == right since the right is a duplicate of left
+        // return the item unencoded as the JS impl
+        if right_vec == left_vec {
+            left
+        } else {
+            let mut node_vec = vec![left_vec, right_vec];
+            node_vec.sort();
 
-        let mut node_vec = vec![left_vec, right_vec];
-        node_vec.sort();
-
-        let flatten_node_vec: Vec<u8> = node_vec.into_iter().flatten().collect();
-
-        self.write(&flatten_node_vec);
-        self.hash()
+            let flatten_node_vec: Vec<u8> = node_vec.into_iter().flatten().collect();
+            self.write(&flatten_node_vec);
+            self.hash()
+        }
     }
 }
 

validator_worker/src/follower.rs

@@ -60,7 +60,6 @@ async fn on_new_state<'a, A: Adapter + 'static>(
 ) -> Result<NewStateResult, Box<dyn Error>> {
     let proposed_balances = new_state.balances.clone();
     let proposed_state_root = new_state.state_root.clone();
-
     if proposed_state_root != hex::encode(get_state_root_hash(&iface, &proposed_balances)?) {
         return Ok(on_error(&iface, &new_state, InvalidNewState::RootHash).await);
     }