Address is generated with VMAppState, and it increments the nonce too.

state/state.go

@@ -277,8 +277,10 @@ func (s *State) ExecTx(tx_ blk.Tx, runCall bool) error {
 		return nil
 
 	case *blk.CallTx:
+		var inAcc, outAcc *account.Account
+
 		// Validate input
-		inAcc := s.GetAccount(tx.Input.Address)
+		inAcc = s.GetAccount(tx.Input.Address)
 		if inAcc == nil {
 			return blk.ErrTxInvalidAddress
 		}
@@ -295,13 +297,16 @@ func (s *State) ExecTx(tx_ blk.Tx, runCall bool) error {
 			return blk.ErrTxInsufficientFunds
 		}
 
-		// Validate output
-		if len(tx.Address) != 20 {
-			return blk.ErrTxInvalidAddress
-		}
-		outAcc := s.GetAccount(tx.Address)
-		if outAcc == nil {
-			return blk.ErrTxInvalidAddress
+		createAccount := len(tx.Address) == 0
+		if !createAccount {
+			// Validate output
+			if len(tx.Address) != 20 {
+				return blk.ErrTxInvalidAddress
+			}
+			outAcc = s.GetAccount(tx.Address)
+			if outAcc == nil {
+				return blk.ErrTxInvalidAddress
+			}
 		}
 
 		// Good!
@@ -316,9 +321,18 @@ func (s *State) ExecTx(tx_ blk.Tx, runCall bool) error {
 				BlockTime:   s.LastBlockTime.Unix(),
 				GasLimit:    10000000,
 			}
-			caller := toVMAccount(inAcc)
-			callee := toVMAccount(outAcc)
-			appState.AddAccount(caller) // because we adjusted by input above.
+			var caller, callee *vm.Account
+			var err error
+			caller = toVMAccount(inAcc)
+			if outAcc == nil {
+				callee = toVMAccount(outAcc)
+			} else {
+				callee, err = appState.CreateAccount(caller)
+				if err != nil {
+					return err
+				}
+			}
+			appState.AddAccount(caller) // because we adjusted by input above, and bumped nonce maybe.
 			appState.AddAccount(callee) // because we adjusted by input above.
 			vmach := vm.NewVM(appState, params, caller.Address)
 			gas := tx.GasLimit
@@ -330,6 +344,9 @@ func (s *State) ExecTx(tx_ blk.Tx, runCall bool) error {
 				// Throw away 'appState' which holds incomplete updates.
 			} else {
 				// Success
+				if createAccount {
+					callee.Code = ret
+				}
 				appState.Sync()
 			}
 			// Create a receipt from the ret and whether errored.
@@ -339,6 +356,8 @@ func (s *State) ExecTx(tx_ blk.Tx, runCall bool) error {
 			// the proposer determines the order of txs.
 			// So mempool will skip the actual .Call(),
 			// and only deduct from the caller's balance.
+			inAcc.Balance -= value
+			s.UpdateAccount(inAcc)
 		}
 
 		return nil

state/vm_app_state.go

@@ -8,6 +8,7 @@ import (
 	. "github.com/tendermint/tendermint/common"
 	"github.com/tendermint/tendermint/merkle"
 	"github.com/tendermint/tendermint/vm"
+	"github.com/tendermint/tendermint/vm/sha3"
 )
 
 // Converts state.Account to vm.Account struct.
@@ -115,7 +116,18 @@ func (vas *VMAppState) DeleteAccount(account *vm.Account) error {
 	}
 }
 
-func (vas *VMAppState) CreateAccount(addr vm.Word) (*vm.Account, error) {
+// Creates a 20 byte address and bumps the creator's nonce.
+func (vas *VMAppState) CreateAccount(creator *vm.Account) (*vm.Account, error) {
+
+	// Generate an address
+	nonce := creator.Nonce
+	creator.Nonce += 1
+	temp := make([]byte, 32+8)
+	copy(temp, creator.Address[:])
+	vm.PutUint64(temp[32:], nonce)
+	addr := vm.RightPadWord(sha3.Sha3(temp)[:20])
+
+	// Create account from address.
 	account, deleted := unpack(vas.accounts[addr.String()])
 	if deleted || account == nil {
 		account = &vm.Account{
@@ -128,7 +140,8 @@ func (vas *VMAppState) CreateAccount(addr vm.Word) (*vm.Account, error) {
 		vas.accounts[addr.String()] = AccountInfo{account, false}
 		return account, nil
 	} else {
-		return nil, Errorf("Account already exists: %X", addr)
+		panic(Fmt("Could not create account, address already exists: %X", addr))
+		// return nil, Errorf("Account already exists: %X", addr)
 	}
 }
 

vm/test/fake_app_state.go

@@ -5,6 +5,7 @@ import (
 
 	. "github.com/tendermint/tendermint/common"
 	. "github.com/tendermint/tendermint/vm"
+	"github.com/tendermint/tendermint/vm/sha3"
 )
 
 type FakeAppState struct {
@@ -43,7 +44,8 @@ func (fas *FakeAppState) DeleteAccount(account *Account) error {
 	}
 }
 
-func (fas *FakeAppState) CreateAccount(addr Word) (*Account, error) {
+func (fas *FakeAppState) CreateAccount(creator *Account) (*Account, error) {
+	addr := createAddress(creator)
 	account := fas.accounts[addr.String()]
 	if account == nil {
 		return &Account{
@@ -102,16 +104,24 @@ func main() {
 	ourVm := NewVM(appState, params, Zero)
 
 	// Create accounts
-	account1, err := appState.CreateAccount(Uint64ToWord(100))
-	if err != nil {
-		panic(err)
+	account1 := &Account{
+		Address: Uint64ToWord(100),
 	}
-	account2, err := appState.CreateAccount(Uint64ToWord(101))
-	if err != nil {
-		panic(err)
+	account2 := &Account{
+		Address: Uint64ToWord(101),
 	}
 
 	var gas uint64 = 1000
 	output, err := ourVm.Call(account1, account2, []byte{0x60, 0x01, 0x60, 0x01}, []byte{}, 0, &gas)
 	fmt.Printf("Output: %v Error: %v\n", output, err)
 }
+
+// Creates a 20 byte address and bumps the nonce.
+func createAddress(creator *Account) Word {
+	nonce := creator.Nonce
+	creator.Nonce += 1
+	temp := make([]byte, 32+8)
+	copy(temp, creator.Address[:])
+	PutUint64(temp[32:], nonce)
+	return RightPadWord(sha3.Sha3(temp)[:20])
+}

vm/types.go

@@ -48,7 +48,7 @@ type AppState interface {
 	GetAccount(addr Word) (*Account, error)
 	UpdateAccount(*Account) error
 	DeleteAccount(*Account) error
-	CreateAccount(addr Word) (*Account, error)
+	CreateAccount(*Account) (*Account, error)
 
 	// Storage
 	GetStorage(Word, Word) (Word, error)

vm/vm.go

@@ -46,6 +46,7 @@ func NewVM(appState AppState, params Params, origin Word) *VM {
 	}
 }
 
+// CONTRACT appState is aware of caller and callee, so we can just mutate them.
 // value: To be transferred from caller to callee. Refunded upon error.
 // gas:   Available gas. No refunds for gas.
 func (vm *VM) Call(caller, callee *Account, code, input []byte, value uint64, gas *uint64) (output []byte, err error) {
@@ -541,14 +542,9 @@ func (vm *VM) call(caller, callee *Account, code, input []byte, value uint64, ga
 				return nil, firstErr(err, ErrInsufficientBalance)
 			}
 
-			// Create a new address
-			nonce := caller.Nonce
-			addr := createAddress(caller.Address, nonce)
-			caller.Nonce += 1
-
 			// TODO charge for gas to create account _ the code length * GasCreateByte
 
-			newAccount, err := vm.appState.CreateAccount(addr)
+			newAccount, err := vm.appState.CreateAccount(caller)
 			if err != nil {
 				stack.Push(Zero)
 				fmt.Printf(" (*) 0x0 %v\n", err)
@@ -708,14 +704,6 @@ func useGas(gas *uint64, gasToUse uint64) bool {
 	}
 }
 
-// Creates a 20 byte address from the creatorAddr and nonce.
-func createAddress(creatorAddr Word, nonce uint64) Word {
-	temp := make([]byte, 32+8)
-	copy(temp, creatorAddr[:])
-	PutUint64(temp[32:], nonce)
-	return RightPadWord(sha3.Sha3(temp)[:20])
-}
-
 func transfer(from, to *Account, amount uint64) error {
 	if from.Balance < amount {
 		return ErrInsufficientBalance