native: don't call CreateNativeContractHash() in oracle contract

Move oracleScript from global context to Oracle itself. We have the hash
already computed by NewContractMD, there is no need to repeat this
calculation.

pkg/core/blockchain.go

@@ -1395,7 +1395,7 @@ func (bc *Blockchain) verifyTxAttributes(tx *transaction.Transaction, isPartialT
 			if !hasOracle {
 				return fmt.Errorf("%w: oracle tx is not signed by oracle nodes", ErrInvalidAttribute)
 			}
-			if !bytes.Equal(tx.Script, native.GetOracleResponseScript()) {
+			if !bytes.Equal(tx.Script, bc.contracts.Oracle.GetOracleResponseScript()) {
 				return fmt.Errorf("%w: oracle tx has invalid script", ErrInvalidAttribute)
 			}
 			resp := tx.Attributes[i].Value.(*transaction.OracleResponse)

pkg/core/blockchain_test.go

@@ -500,7 +500,7 @@ func TestVerifyTx(t *testing.T) {
 			// We need to create new transaction,
 			// because hashes are cached after signing.
 			getOracleTx := func(t *testing.T) *transaction.Transaction {
-				tx := bc.newTestTx(h, native.GetOracleResponseScript())
+				tx := bc.newTestTx(h, orc.GetOracleResponseScript())
 				resp := &transaction.OracleResponse{
 					ID:     1,
 					Code:   transaction.Success,

pkg/core/native/oracle.go

@@ -34,7 +34,8 @@ type Oracle struct {
 	GAS *GAS
 	NEO *NEO
 
-	Desig *Designate
+	Desig        *Designate
+	oracleScript []byte
 }
 
 const (
@@ -49,20 +50,6 @@ const (
 	oracleRequestPrice = 5000_0000
 )
 
-var oracleScript []byte
-
-func init() {
-	_, h := state.CreateNativeContractHash(oracleContractID)
-	w := io.NewBufBinWriter()
-	emit.Int(w.BinWriter, 0)
-	emit.Opcodes(w.BinWriter, opcode.NEWARRAY)
-	emit.Int(w.BinWriter, int64(callflag.All))
-	emit.String(w.BinWriter, "finish")
-	emit.Bytes(w.BinWriter, h.BytesBE())
-	emit.Syscall(w.BinWriter, interopnames.SystemContractCall)
-	oracleScript = w.Bytes()
-}
-
 var (
 	prefixIDList    = []byte{6}
 	prefixRequest   = []byte{7}
@@ -78,16 +65,18 @@ var (
 	ErrResponseNotFound = errors.New("oracle response not found")
 )
 
-// GetOracleResponseScript returns script for transaction with oracle response.
-func GetOracleResponseScript() []byte {
-	b := make([]byte, len(oracleScript))
-	copy(b, oracleScript)
-	return b
-}
-
 func newOracle() *Oracle {
 	o := &Oracle{ContractMD: *interop.NewContractMD(nativenames.Oracle, oracleContractID)}
 
+	w := io.NewBufBinWriter()
+	emit.Int(w.BinWriter, 0)
+	emit.Opcodes(w.BinWriter, opcode.NEWARRAY)
+	emit.Int(w.BinWriter, int64(callflag.All))
+	emit.String(w.BinWriter, "finish")
+	emit.Bytes(w.BinWriter, o.Hash.BytesBE())
+	emit.Syscall(w.BinWriter, interopnames.SystemContractCall)
+	o.oracleScript = w.Bytes()
+
 	desc := newDescriptor("request", smartcontract.VoidType,
 		manifest.NewParameter("url", smartcontract.StringType),
 		manifest.NewParameter("filter", smartcontract.StringType),
@@ -115,6 +104,13 @@ func newOracle() *Oracle {
 	return o
 }
 
+// GetOracleResponseScript returns script for transaction with oracle response.
+func (o *Oracle) GetOracleResponseScript() []byte {
+	b := make([]byte, len(o.oracleScript))
+	copy(b, o.oracleScript)
+	return b
+}
+
 // OnPersist implements Contract interface.
 func (o *Oracle) OnPersist(ic *interop.Context) error {
 	return nil

pkg/core/native_oracle_test.go

@@ -153,7 +153,7 @@ func TestOracle_Request(t *testing.T) {
 	err = bc.contracts.Designate.DesignateAsRole(ic, native.RoleOracle, keys.PublicKeys{pub})
 	require.NoError(t, err)
 
-	tx = transaction.New(netmode.UnitTestNet, native.GetOracleResponseScript(), 0)
+	tx = transaction.New(netmode.UnitTestNet, orc.GetOracleResponseScript(), 0)
 	ic.Tx = tx
 	ic.Block = bc.newBlock(tx)
 
@@ -203,7 +203,7 @@ func TestOracle_Request(t *testing.T) {
 		_, err := orc.GetRequestInternal(bc.dao, reqID) // ensure ID is 2
 		require.NoError(t, err)
 
-		tx = transaction.New(netmode.UnitTestNet, native.GetOracleResponseScript(), 0)
+		tx = transaction.New(netmode.UnitTestNet, orc.GetOracleResponseScript(), 0)
 		tx.Attributes = []transaction.Attribute{{
 			Type: transaction.OracleResponseT,
 			Value: &transaction.OracleResponse{