Improve logging for block verification failure (#2224)

snow/engine/snowman/transitive.go

@@ -965,9 +965,12 @@ func (t *Transitive) addToNonVerifieds(blk snowman.Block) {
 // addUnverifiedBlockToConsensus returns whether the block was added and an
 // error if one occurred while adding it to consensus.
 func (t *Transitive) addUnverifiedBlockToConsensus(ctx context.Context, blk snowman.Block) (bool, error) {
+	blkID := blk.ID()
+
 	// make sure this block is valid
 	if err := blk.Verify(ctx); err != nil {
 		t.Ctx.Log.Debug("block verification failed",
+			zap.Stringer("blkID", blkID),
 			zap.Error(err),
 		)
 
@@ -976,7 +979,6 @@ func (t *Transitive) addUnverifiedBlockToConsensus(ctx context.Context, blk snow
 		return false, nil
 	}
 
-	blkID := blk.ID()
 	t.nonVerifieds.Remove(blkID)
 	t.nonVerifiedCache.Evict(blkID)
 	t.metrics.numNonVerifieds.Set(float64(t.nonVerifieds.Len()))

vms/proposervm/block.go

@@ -135,7 +135,11 @@ func (p *postForkCommonComponents) Verify(
 			return err
 		}
 		if childPChainHeight > currentPChainHeight {
-			return errPChainHeightNotReached
+			return fmt.Errorf("%w: %d > %d",
+				errPChainHeightNotReached,
+				childPChainHeight,
+				currentPChainHeight,
+			)
 		}
 
 		childHeight := child.Height()

vms/proposervm/pre_fork_block.go

@@ -5,6 +5,7 @@ package proposervm
 
 import (
 	"context"
+	"fmt"
 	"time"
 
 	"go.uber.org/zap"
@@ -128,7 +129,11 @@ func (b *preForkBlock) verifyPostForkChild(ctx context.Context, child *postForkB
 		return err
 	}
 	if childPChainHeight > currentPChainHeight {
-		return errPChainHeightNotReached
+		return fmt.Errorf("%w: %d > %d",
+			errPChainHeightNotReached,
+			childPChainHeight,
+			currentPChainHeight,
+		)
 	}
 	if childPChainHeight < b.vm.minimumPChainHeight {
 		return errPChainHeightTooLow