syncer: fix issues when switching to core.Consensus (#418)

- when confirmed blocks passed to core.Consensus
   aren't continuous in position in some chain, the
   pulling would skip those missing blocks.
   - fix: when some block is missing, avoid adding it
      and all blocks after it to core.Consensus.
- we need to avoid the receive channel of network
   module full.
   - fix: during switching to core.Consensus, we
      need to launch a dummy receiver to receive
      from receive channel of network module.
   - fix: between the period during core.Consensus
      created and before running, a dummy receiver is
      also required to receive from receive channel of
      network module.

1 files changed, 5 insertions, 3 deletions

diff --git a/integration_test/consensus_test.go b/integration_test/consensus_test.go
index 99de7c9..fc6bb47 100644
--- a/integration_test/consensus_test.go
+++ b/integration_test/consensus_test.go
@@ -367,8 +367,8 @@ func (s *ConsensusTestSuite) TestSync() {
 	}
 	// Clean syncNode's network receive channel, or it might exceed the limit
 	// and block other go routines.
-	dummyReceiverCtxCancel := test.LaunchDummyReceiver(
-		context.Background(), syncNode.network)
+	dummyReceiverCtxCancel, dummyFinished := utils.LaunchDummyReceiver(
+		context.Background(), syncNode.network.ReceiveChan(), nil)
 ReachAlive:
 	for {
 		// Check if any error happened or sleep for a period of time.
@@ -390,6 +390,7 @@ ReachAlive:
 			}
 		}
 		dummyReceiverCtxCancel()
+		<-dummyFinished
 		break
 	}
 	// Initiate Syncer.
@@ -456,7 +457,8 @@ ReachAlive:
 					stoppedNode.con.Stop()
 					stoppedNode.con = nil
 					fmt.Println("one node stopped", stoppedNode.ID)
-					test.LaunchDummyReceiver(runnerCtx, stoppedNode.network)
+					utils.LaunchDummyReceiver(
+						runnerCtx, stoppedNode.network.ReceiveChan(), nil)
 					continue
 				}
 				if pos.Round < untilRound {