core, eth, trie: reuse trie journals in all our code

1 files changed, 6 insertions, 1 deletions

diff --git a/core/blockchain.go b/core/blockchain.go
index a5f146a2d..1fbcdfc6f 100644
--- a/core/blockchain.go
+++ b/core/blockchain.go
@@ -357,7 +357,12 @@ func (self *BlockChain) AuxValidator() pow.PoW { return self.pow }
 
 // State returns a new mutable state based on the current HEAD block.
 func (self *BlockChain) State() (*state.StateDB, error) {
-	return state.New(self.CurrentBlock().Root(), self.chainDb)
+	return self.StateAt(self.CurrentBlock().Root())
+}
+
+// StateAt returns a new mutable state based on a particular point in time.
+func (self *BlockChain) StateAt(root common.Hash) (*state.StateDB, error) {
+	return self.stateCache.New(root)
 }
 
 // Reset purges the entire blockchain, restoring it to its genesis state.