resolve igor's comments

core/blockchain.go

@@ -597,7 +597,7 @@ func (bc *BlockChain) tryRewindBadBlocks() {
  snaps := bc.snaps
  // Verified and Result is false
  if snaps != nil && snaps.Snapshot(block.Root()) != nil &&
- snaps.Snapshot(block.Root()).Verified() && !snaps.Snapshot(block.Root()).WaitVerified() {
+ snaps.Snapshot(block.Root()).Verified() && !snaps.Snapshot(block.Root()).WaitAndGetVerifyRes() {
  // Rewind by one block
  log.Warn("current block verified failed, rewind to its parent", "height", block.NumberU64(), "hash", block.Hash())
  bc.futureBlocks.Remove(block.Hash())

core/state/snapshot/difflayer.go

@@ -260,8 +260,8 @@ func (dl *diffLayer) Root() common.Hash {
  return dl.root
 }
 
-// WaitVerified will wait until the diff layer been verified and return the verification result
-func (dl *diffLayer) WaitVerified() bool {
+// WaitAndGetVerifyRes will wait until the diff layer been verified and return the verification result
+func (dl *diffLayer) WaitAndGetVerifyRes() bool {
  if dl.verifiedCh == nil {
  return true
  }

core/state/snapshot/disklayer.go

@@ -49,7 +49,7 @@ func (dl *diskLayer) Root() common.Hash {
  return dl.root
 }
 
-func (dl *diskLayer) WaitVerified() bool {
+func (dl *diskLayer) WaitAndGetVerifyRes() bool {
  return true
 }
 

core/state/snapshot/snapshot.go

@@ -101,8 +101,8 @@ type Snapshot interface {
  // Root returns the root hash for which this snapshot was made.
  Root() common.Hash
 
- // WaitVerified will wait until the snapshot been verified
- WaitVerified() bool
+ // WaitAndGetVerifyRes will wait until the snapshot been verified and return verification result
+ WaitAndGetVerifyRes() bool
 
  // Verified returns whether the snapshot is verified
  Verified() bool

core/state/statedb.go

@@ -170,7 +170,7 @@ func newStateDB(root common.Hash, db Database, snaps *snapshot.Tree) (*StateDB,
 
  snapVerified := sdb.snap != nil && sdb.snap.Verified()
  tr, err := db.OpenTrie(root)
- // return error when 1. failed to open trie and 2. the snap is not nil and done verification
+ // return error when 1. failed to open trie and 2. the snap is nil or the snap is not nil and done verification
  if err != nil && (sdb.snap == nil || snapVerified) {
  return nil, err
  }
@@ -1020,7 +1020,7 @@ func (s *StateDB) AccountsIntermediateRoot() error {
 
  // We need wait for the parent trie to commit
  if s.snap != nil {
- if valid := s.snap.WaitVerified(); !valid {
+ if valid := s.snap.WaitAndGetVerifyRes(); !valid {
  return fmt.Errorf("verification on parent snap failed")
  }
  }

eth/tracers/api.go

@@ -558,7 +558,7 @@ func (api *API) IntermediateRoots(ctx context.Context, hash common.Hash, config
  // so any modifications are written to the trie
  root, err := statedb.IntermediateRoot(deleteEmptyObjects)
  if err != nil {
- return roots, err
+ return nil, err
  }
  roots = append(roots, root)
  }