core/state, trie, light: Add a DeleteAccount method

core/state/database.go

@@ -87,6 +87,9 @@ type Trie interface {
 	// found in the database, a trie.MissingNodeError is returned.
 	TryDelete(key []byte) error
 
+	// DeleteACcount abstracts an account deletion from the trie.
+	DeleteAccount(key []byte) error
+
 	// Hash returns the root hash of the trie. It does not write to the database and
 	// can be used even if the trie doesn't have one.
 	Hash() common.Hash

core/state/statedb.go

@@ -484,7 +484,7 @@ func (s *StateDB) deleteStateObject(obj *stateObject) {
 	}
 	// Delete the account from the trie
 	addr := obj.Address()
-	if err := s.trie.TryDelete(addr[:]); err != nil {
+	if err := s.trie.DeleteAccount(addr[:]); err != nil {
 		s.setError(fmt.Errorf("deleteStateObject (%x) error: %v", addr[:], err))
 	}
 }

light/trie.go

@@ -153,6 +153,13 @@ func (t *odrTrie) TryDelete(key []byte) error {
 	})
 }
 
+func (t *odrTrie) DeleteAccount(key []byte) error {
+	key = crypto.Keccak256(key)
+	return t.do(key, func() error {
+		return t.trie.TryDelete(key)
+	})
+}
+
 func (t *odrTrie) Commit(collectLeaf bool) (common.Hash, *trie.NodeSet, error) {
 	if t.trie == nil {
 		return t.id.Root, nil, nil

trie/secure_trie.go

@@ -189,6 +189,12 @@ func (t *StateTrie) TryDelete(key []byte) error {
 	return t.trie.TryDelete(hk)
 }
 
+func (t *StateTrie) DeleteAccount(key []byte) error {
+	hk := t.hashKey(key)
+	delete(t.getSecKeyCache(), string(hk))
+	return t.trie.TryDelete(hk)
+}
+
 // GetKey returns the sha3 preimage of a hashed key that was
 // previously used to store a value.
 func (t *StateTrie) GetKey(shaKey []byte) []byte {