Fix a bug that Tendermint fails when a locked proposal is not imported

Author: majecty

core/src/consensus/tendermint/worker.rs

@@ -655,8 +655,13 @@ impl Worker {
  TwoThirdsMajority::Lock(_, block_hash) => Some(*block_hash),
  };
  let block_hash = block_hash_candidate.filter(|hash| {
- let block =
- self.client().block(&BlockId::Hash(*hash)).expect("Already got imported block hash");
+ let block = match self.client().block(&BlockId::Hash(*hash)) {
+ Some(block) => block,
+ // When a node locks on a proposal and doesn't imported the proposal yet,
+ // we could not check the proposal's generated time.
+ // To make the network healthier in the corner case, we send a prevote message to the locked block.
+ None => return true,
+ };
  self.is_generation_time_relevant(&block.decode_header())
  });
  self.generate_and_broadcast_message(block_hash, is_restoring);