Incorrect block number for epoch ending exit events (0xPolygon#1299)

* Bug fix

* Add logs

consensus/polybft/checkpoint_manager.go

@@ -11,6 +11,7 @@ import (
 	bls "github.com/0xPolygon/polygon-edge/consensus/polybft/signer"
 	"github.com/0xPolygon/polygon-edge/contracts"
 	"github.com/0xPolygon/polygon-edge/helper/hex"
+	"github.com/0xPolygon/polygon-edge/merkle-tree"
 	"github.com/0xPolygon/polygon-edge/txrelayer"
 	"github.com/0xPolygon/polygon-edge/types"
 	metrics "github.com/armon/go-metrics"
@@ -272,19 +273,29 @@ func (c *checkpointManager) isCheckpointBlock(blockNumber uint64, isEpochEndingB
 // PostBlock is called on every insert of finalized block (either from consensus or syncer)
 // It will read any exit event that happened in block and insert it to state boltDb
 func (c *checkpointManager) PostBlock(req *PostBlockRequest) error {
-	epoch := req.Epoch
+	var (
+		epoch = req.Epoch
+		block = req.FullBlock.Block.Number()
+	)
+
 	if req.IsEpochEndingBlock {
 		// exit events that happened in epoch ending blocks,
 		// should be added to the tree of the next epoch
 		epoch++
+		block++
 	}
 
 	// commit exit events only when we finalize a block
-	events, err := getExitEventsFromReceipts(epoch, req.FullBlock.Block.Number(), req.FullBlock.Receipts)
+	events, err := getExitEventsFromReceipts(epoch, block, req.FullBlock.Receipts)
 	if err != nil {
 		return err
 	}
 
+	if len(events) > 0 {
+		c.logger.Debug("Gotten exit events from logs on block",
+			"eventsNum", len(events), "block", req.FullBlock.Block.Number())
+	}
+
 	if err := c.state.CheckpointStore.insertExitEvents(events); err != nil {
 		return err
 	}
@@ -327,6 +338,8 @@ func (c *checkpointManager) BuildEventRoot(epoch uint64) (types.Hash, error) {
 
 // GenerateExitProof generates proof of exit event
 func (c *checkpointManager) GenerateExitProof(exitID uint64) (types.Proof, error) {
+	c.logger.Debug("Generating proof for exit", "exitID", exitID)
+
 	exitEvent, err := c.state.CheckpointStore.getExitEvent(exitID)
 	if err != nil {
 		return types.Proof{}, err
@@ -409,6 +422,8 @@ func (c *checkpointManager) GenerateExitProof(exitID uint64) (types.Proof, error
 		return types.Proof{}, err
 	}
 
+	c.logger.Debug("Generated proof for exit", "exitID", exitID, "leafIndex", leafIndex, "proofLen", len(proof))
+
 	return types.Proof{
 		Data: proof,
 		Metadata: map[string]interface{}{
@@ -454,3 +469,20 @@ func getExitEventsFromReceipts(epoch, block uint64, receipts []*types.Receipt) (
 
 	return events, nil
 }
+
+// createExitTree creates an exit event merkle tree from provided exit events
+func createExitTree(exitEvents []*ExitEvent) (*merkle.MerkleTree, error) {
+	numOfEvents := len(exitEvents)
+	data := make([][]byte, numOfEvents)
+
+	for i := 0; i < numOfEvents; i++ {
+		b, err := ExitEventInputsABIType.Encode(exitEvents[i])
+		if err != nil {
+			return nil, err
+		}
+
+		data[i] = b
+	}
+
+	return merkle.NewMerkleTree(data)
+}

consensus/polybft/checkpoint_manager_test.go

@@ -325,11 +325,12 @@ func TestCheckpointManager_PostBlock(t *testing.T) {
 		require.NoError(t, checkpointManager.PostBlock(req))
 
 		exitEvents, err := state.CheckpointStore.getExitEvents(epoch+1, func(exitEvent *ExitEvent) bool {
-			return exitEvent.BlockNumber == block
+			return exitEvent.BlockNumber == block+1
 		})
 
 		require.NoError(t, err)
 		require.Len(t, exitEvents, numOfReceipts)
+		require.Equal(t, uint64(block+1), exitEvents[0].BlockNumber)
 		require.Equal(t, uint64(epoch+1), exitEvents[0].EpochNumber)
 	})
 }

consensus/polybft/consensus_runtime.go

@@ -11,7 +11,6 @@ import (
 
 	"github.com/0xPolygon/polygon-edge/consensus/polybft/contractsapi"
 	"github.com/0xPolygon/polygon-edge/consensus/polybft/wallet"
-	"github.com/0xPolygon/polygon-edge/merkle-tree"
 	"github.com/0xPolygon/polygon-edge/txrelayer"
 	"github.com/0xPolygon/polygon-edge/types"
 
@@ -952,23 +951,6 @@ func (c *consensusRuntime) getFirstBlockOfEpoch(epochNumber uint64, latestHeader
 	return firstBlockInEpoch, nil
 }
 
-// createExitTree creates an exit event merkle tree from provided exit events
-func createExitTree(exitEvents []*ExitEvent) (*merkle.MerkleTree, error) {
-	numOfEvents := len(exitEvents)
-	data := make([][]byte, numOfEvents)
-
-	for i := 0; i < numOfEvents; i++ {
-		b, err := ExitEventInputsABIType.Encode(exitEvents[i])
-		if err != nil {
-			return nil, err
-		}
-
-		data[i] = b
-	}
-
-	return merkle.NewMerkleTree(data)
-}
-
 // getSealersForBlock checks who sealed a given block and updates the counter
 func getSealersForBlock(sealersCounter map[types.Address]uint64,
 	blockExtra *Extra, validators AccountSet) error {