From e702896bee1784079f58eeab57966227e62fa3c7 Mon Sep 17 00:00:00 2001
From: Paul Hauner <paul@paulhauner.com>
Date: Tue, 26 Mar 2019 13:28:21 +1100
Subject: [PATCH] Fix ssz decoding bug

---
 beacon_node/eth2-libp2p/src/behaviour.rs | 28 +++++++++++++++++++++---
 1 file changed, 25 insertions(+), 3 deletions(-)

diff --git a/beacon_node/eth2-libp2p/src/behaviour.rs b/beacon_node/eth2-libp2p/src/behaviour.rs
index 592fd6fb1e..2865971838 100644
--- a/beacon_node/eth2-libp2p/src/behaviour.rs
+++ b/beacon_node/eth2-libp2p/src/behaviour.rs
@@ -195,7 +195,7 @@ pub enum BehaviourEvent {
 }
 
 /// Messages that are passed to and from the pubsub (Gossipsub) behaviour.
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, PartialEq)]
 pub enum PubsubMessage {
     /// Gossipsub message providing notification of a new block.
     Block(BlockRootSlot),
@@ -223,11 +223,11 @@ impl Decodable for PubsubMessage {
     fn ssz_decode(bytes: &[u8], index: usize) -> Result<(Self, usize), DecodeError> {
         let (id, index) = u32::ssz_decode(bytes, index)?;
         match id {
-            1 => {
+            0 => {
                 let (block, index) = BlockRootSlot::ssz_decode(bytes, index)?;
                 Ok((PubsubMessage::Block(block), index))
             }
-            2 => {
+            1 => {
                 let (attestation, index) = Attestation::ssz_decode(bytes, index)?;
                 Ok((PubsubMessage::Attestation(attestation), index))
             }
@@ -235,3 +235,25 @@ impl Decodable for PubsubMessage {
         }
     }
 }
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    use types::*;
+
+    #[test]
+    fn ssz_encoding() {
+        let original = PubsubMessage::Block(BlockRootSlot {
+            block_root: Hash256::from_slice(&[42; 32]),
+            slot: Slot::new(4),
+        });
+
+        let encoded = ssz_encode(&original);
+
+        println!("{:?}", encoded);
+
+        let (decoded, _i) = PubsubMessage::ssz_decode(&encoded, 0).unwrap();
+
+        assert_eq!(original, decoded);
+    }
+}