Add RLP encoding for AggregateVote

src/state/aggregate_vote.rs

@@ -1,5 +1,6 @@
 use super::utils::types::*;
 use super::utils::bls::AggregateSignature;
+use super::rlp::{ RlpStream, Encodable };
 
 pub struct AggregateVote {
     pub shard_id: u16,
@@ -21,9 +22,22 @@ impl AggregateVote {
     }
 }
 
+/*
+ * RLP Encoding
+ */
+impl Encodable for AggregateVote {
+    fn rlp_append(&self, s: &mut RlpStream) {
+        s.append(&self.shard_id);
+        s.append(&self.shard_block_hash);
+        s.append(&self.notary_bitfield);
+        // s.append(&self.aggregate_sig);   // TODO: represent this in RLP
+    }
+}
+
 
 #[cfg(test)]
 mod tests {
+    use super::super::rlp;
     use super::*;
 
     #[test]
@@ -34,4 +48,20 @@ mod tests {
         assert_eq!(v.shard_id, id);
         assert_eq!(v.shard_block_hash, hash);
     }
+    
+    #[test]
+    fn test_serialization() {
+        let a = AggregateVote {
+            shard_id: 100,
+            shard_block_hash: Sha256Digest::zero(),
+            notary_bitfield: Vec::new(),
+            aggregate_sig: AggregateSignature::new()
+        };
+        let e = rlp::encode(&a);
+        assert_eq!(e.len(), 35);
+        assert_eq!(e[0], 100);
+        assert_eq!(e[1], 160);
+        assert_eq!(e[2..34], [0; 32]);
+        assert_eq!(e[34], 128);
+    }
 }