implementing the proper fix

Author: sasurobert

mock/contracts/transferAndExecuteSC.go

@@ -1,6 +1,7 @@
 package contracts
 
 import (
+	"encoding/hex"
 	"fmt"
 	"math/big"
 
@@ -64,6 +65,27 @@ func TransferEGLDToParent(instanceMock *mock.InstanceMock, config interface{}) {
 	})
 }
 
+func TransferAndExecuteWithBuiltIn(instanceMock *mock.InstanceMock, config interface{}) {
+	instanceMock.AddMockMethod("transferAndExecuteWithBuiltIn", func() *mock.InstanceMock {
+		testConfig := config.(*test.TestConfig)
+		host := instanceMock.Host
+		instance := mock.GetMockInstance(host)
+
+		_ = host.Metering().UseGasBounded(testConfig.GasUsedByChild)
+
+		transferString := "ESDTTransfer@" + hex.EncodeToString([]byte("XYY-ABCDEF")) + "@" + hex.EncodeToString(big.NewInt(100000).Bytes())
+		vmhooks.TransferValueExecuteWithTypedArgs(host,
+			test.UserAddress,
+			big.NewInt(0),
+			1,
+			[]byte(transferString),
+			[][]byte{},
+		)
+
+		return instance
+	})
+}
+
 // GetChildAddressForTransfer -
 func GetChildAddressForTransfer(transfer int) []byte {
 	return testcommon.MakeTestSCAddress(fmt.Sprintf("childSC-%d", transfer))

vmhost/hosttest/execution_gas_test.go

@@ -174,6 +174,36 @@ func TestGasUsed_SingleContract_TransferFromChild(t *testing.T) {
 	assert.Nil(t, err)
 }
 
+func TestGasUsed_SingleContract_TransferFromChildWithBuiltIn(t *testing.T) {
+	testConfig := makeTestConfig()
+
+	_, err := test.BuildMockInstanceCallTest(t).
+		WithContracts(
+			test.CreateMockContract(test.ParentAddress).
+				WithBalance(testConfig.ParentBalance).
+				WithCodeMetadata([]byte{0, vmcommon.MetadataPayable}).
+				WithConfig(testConfig).
+				WithMethods(contracts.ExecOnDestCtxSingleCallParentMock),
+			test.CreateMockContract(test.ChildAddress).
+				WithBalance(testConfig.ChildBalance).
+				WithConfig(testConfig).
+				WithMethods(contracts.TransferAndExecuteWithBuiltIn)).
+		WithInput(test.CreateTestContractCallInputBuilder().
+			WithRecipientAddr(test.ParentAddress).
+			WithGasProvided(testConfig.GasProvided).
+			WithFunction("execOnDestCtxSingleCall").
+			WithArguments(test.ChildAddress, []byte("transferAndExecuteWithBuiltIn")).
+			Build()).
+		WithSetup(func(host vmhost.VMHost, world *worldmock.MockWorld) {
+			createMockBuiltinFunctions(t, host, world)
+			setZeroCodeCosts(host)
+		}).
+		AndAssertResults(func(world *worldmock.MockWorld, verify *test.VMOutputVerifier) {
+			verify.ReturnCode(vmcommon.ExecutionFailed)
+		})
+	assert.Nil(t, err)
+}
+
 func TestGasUsed_ExecuteOnDestChain(t *testing.T) {
 	alphaAddress := test.MakeTestSCAddress("alpha")
 	betaAddress := test.MakeTestSCAddress("beta")

vmhost/vmhooks/baseOps.go

@@ -848,7 +848,7 @@ func TransferValueExecuteWithTypedArgs(
 
 	lastRound := host.Blockchain().LastRound()
 	if host.IsBuiltinFunctionCall([]byte(data)) &&
-		lastRound > uint64(host.EnableEpochsHandler().GetActivationEpoch(vmhost.CheckBuiltInCallOnTransferValueAndFailExecutionFlag)) {
+		lastRound >= uint64(host.EnableEpochsHandler().GetActivationEpoch(vmhost.CheckBuiltInCallOnTransferValueAndFailExecutionFlag)) {
 		WithFaultAndHost(host, vmhost.ErrTransferValueOnESDTCall, runtime.BaseOpsErrorShouldFailExecution())
 		return 1
 	}