Only clean votes if the block has been finalized (#1290)

CHANGELOG.md

@@ -4,8 +4,9 @@
 
 Unreleased changes.
 
-- [#1174](https://github.com/Zilliqa/zq2/pull/1174): Limit the returned size of `GetSmartContractState` when the `state_rpc_limit` configuration is set.
+- [#1290](https://github.com/Zilliqa/zq2/pull/1281): Fix over-eager clean up of votes which could cause votes for pending blocks to get lost.
 - [#1281](https://github.com/Zilliqa/zq2/pull/1281): Emit an `ERROR` level log when a node panics.
+- [#1174](https://github.com/Zilliqa/zq2/pull/1174): Limit the returned size of `GetSmartContractState` when the `state_rpc_limit` configuration is set.
 
 ## [0.1.0] - 2024-08-01
 

zilliqa/src/consensus.rs

@@ -811,7 +811,13 @@ impl Consensus {
 
         for key in keys_to_process {
             if let Ok(Some(block)) = self.get_block(&key) {
-                if block.view() < self.view.get_view() {
+                // Remove votes for blocks that have been finalized. However, note that the block hashes which are keys
+                // into `self.votes` are the parent hash of the (potential) block that is being voted on. Therefore, we
+                // subtract one in this condition to ensure there is no chance of removing votes for blocks that still
+                // have a chance of being mined. It is possible this is unnecessary, since `self.finalized_view` is
+                // already at least 2 views behind the head of the chain, but keeping one extra vote in memory doesn't
+                // cost much and does make us more confident that we won't dispose of valid votes.
+                if block.view() < self.finalized_view.saturating_sub(1) {
                     self.votes.remove(&key);
                 }
             } else {