Create object if it doesn't exist.

mpt-witness-generator/state/statedb.go

@@ -623,14 +623,14 @@ func (s *StateDB) setStateObject(object *stateObject) {
 func (s *StateDB) GetOrNewStateObject(addr common.Address) *stateObject {
 	stateObject := s.getStateObject(addr)
 	if stateObject == nil {
-		stateObject, _ = s.createObject(addr)
+		stateObject, _ = s.CreateObject(addr)
 	}
 	return stateObject
 }
 
 // createObject creates a new state object. If there is an existing account with
 // the given address, it is overwritten and returned as the second return value.
-func (s *StateDB) createObject(addr common.Address) (newobj, prev *stateObject) {
+func (s *StateDB) CreateObject(addr common.Address) (newobj, prev *stateObject) {
 	prev = s.getDeletedStateObject(addr) // Note, prev might have been deleted, we need that!
 
 	var prevdestruct bool
@@ -664,7 +664,7 @@ func (s *StateDB) createObject(addr common.Address) (newobj, prev *stateObject)
 //
 // Carrying over the balance ensures that Ether doesn't disappear.
 func (s *StateDB) CreateAccount(addr common.Address) {
-	newObj, prev := s.createObject(addr)
+	newObj, prev := s.CreateObject(addr)
 	if prev != nil {
 		newObj.setBalance(prev.data.Balance)
 	}

mpt-witness-generator/witness/gen_witness_from_infura_blockchain_test.go

@@ -2241,7 +2241,6 @@ func TestNeighbourNodeInHashedBranch(t *testing.T) {
 }
 
 func TestLongKey(t *testing.T) {
-	// Currently, it results into leaf RLP constrain failure.
 	blockNum := 2000069
 	blockNumberParent := big.NewInt(int64(blockNum))
 	blockHeaderParent := oracle.PrefetchBlock(blockNumberParent, true, nil)
@@ -2265,4 +2264,29 @@ func TestLongKey(t *testing.T) {
 	trieModifications := []TrieModification{trieMod1}
 
 	prepareWitness("LongKey", trieModifications, statedb)
+}
+
+func TestTrieDoesNotExist(t *testing.T) {
+	blockNum := 2000003
+	blockNumberParent := big.NewInt(int64(blockNum))
+	blockHeaderParent := oracle.PrefetchBlock(blockNumberParent, true, nil)
+	database := state.NewDatabase(blockHeaderParent)
+	statedb, _ := state.New(blockHeaderParent.Root, database, nil)
+	addr := common.HexToAddress("0xcaac46d9bd68bffb533320545a90cd92c6e98e58")
+
+	statedb.DisableLoadingRemoteAccounts()
+
+	key1 := common.HexToHash("0x0000000000000000000000000000000000000000000000000000000000000000")
+	val1 := common.BigToHash(big.NewInt(int64(17)))
+
+	trieMod1 := TrieModification{
+		Type:    StorageChanged,
+		Key:     key1,
+		Value:   val1,
+		Address: addr,
+	}
+
+	trieModifications := []TrieModification{trieMod1}
+
+	prepareWitness("StorageTrieDoesNotExist", trieModifications, statedb)
 }

mpt-witness-generator/witness/prepare_witness.go

@@ -209,6 +209,11 @@ func obtainTwoProofsAndConvertToWitness(trieModifications []TrieModification, st
 
 			accountProof, aNeighbourNode1, aExtNibbles1, aIsLastLeaf1, aIsNeighbourNodeHashed1, err := statedb.GetProof(addr)
 			check(err)
+
+			if !statedb.Exist(addr) {
+				statedb.CreateObject(addr)
+			}
+
 			storageProof, neighbourNode1, extNibbles1, isLastLeaf1, isNeighbourNodeHashed1, err := statedb.GetStorageProof(addr, tMod.Key)
 			check(err)