Gas refunding

go/integration_test/processor/gas_billing_test.go

@@ -0,0 +1,118 @@
+// Copyright (c) 2024 Fantom Foundation
+//
+// Use of this software is governed by the Business Source License included
+// in the LICENSE file and at fantom.foundation/bsl11.
+//
+// Change Date: 2028-4-16
+//
+// On the date above, in accordance with the Business Source License, use of
+// this software will be governed by the GNU Lesser General Public License v3.
+
+package processor
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/Fantom-foundation/Tosca/go/tosca"
+	"github.com/Fantom-foundation/Tosca/go/tosca/vm"
+	op "github.com/ethereum/go-ethereum/core/vm"
+	"go.uber.org/mock/gomock"
+
+	_ "github.com/Fantom-foundation/Tosca/go/processor/opera" // < registers opera processor for testing
+)
+
+func TestProcessor_GasBillingEndToEnd(t *testing.T) {
+	senderBalance := tosca.NewValue(1000000)
+	gasLimit := tosca.Gas(100000)
+	gasRefund := tosca.Gas(3000)
+	gasPrice := tosca.NewValue(5)
+	gasLeftSuccess := tosca.Gas(5000)
+
+	tests := map[string]struct {
+		result  tosca.Result
+		gasUsed tosca.Gas
+		success bool
+	}{
+		"success": {
+			result: tosca.Result{
+				GasLeft:   gasLeftSuccess,
+				Success:   true,
+				GasRefund: gasRefund,
+			},
+			gasUsed: gasLimit - (gasLeftSuccess - gasLeftSuccess/10 + gasRefund),
+			success: true,
+		},
+		"failed": {
+			result: tosca.Result{
+				GasLeft:   0,
+				Success:   false,
+				GasRefund: gasRefund,
+			},
+			gasUsed: gasLimit,
+			success: false,
+		},
+	}
+
+	ctrl := gomock.NewController(t)
+	interpreter := tosca.NewMockInterpreter(ctrl)
+
+	sender := tosca.Address{1}
+	recipient := tosca.Address{2}
+	before := WorldState{
+		sender: Account{Balance: senderBalance, Nonce: 4},
+		recipient: Account{Balance: tosca.NewValue(0),
+			Code: tosca.Code{
+				byte(vm.PUSH1), byte(0), // < push 0
+				byte(vm.PUSH1), byte(0), // < push 0
+				byte(op.RETURN),
+			},
+		},
+	}
+
+	transaction := tosca.Transaction{
+		Sender:    sender,
+		Recipient: &recipient,
+		GasLimit:  gasLimit,
+		GasPrice:  gasPrice,
+		Nonce:     4,
+	}
+
+	for name, test := range tests {
+		for processorName, processor := range processorsWithInterpreter("mockInterpreter", interpreter) {
+			t.Run(fmt.Sprintf("%s/%s", processorName, name), func(t *testing.T) {
+
+				after := before.Clone()
+				afterBalance := tosca.Sub(senderBalance, gasPrice.Scale(uint64(test.gasUsed)))
+				after[sender] = Account{Balance: afterBalance, Nonce: after[sender].Nonce + 1}
+
+				receipt := tosca.Receipt{
+					Success: test.success,
+					GasUsed: test.gasUsed,
+				}
+
+				scenario := Scenario{
+					Before:      before,
+					Transaction: transaction,
+					After:       after,
+					Receipt:     receipt,
+				}
+
+				interpreter.EXPECT().Run(gomock.Any()).Return(test.result, nil)
+				scenario.Run(t, processor)
+			})
+		}
+	}
+
+}
+
+func processorsWithInterpreter(name string, interpreter tosca.Interpreter) map[string]tosca.Processor {
+	factories := tosca.GetAllRegisteredProcessorFactories()
+	res := map[string]tosca.Processor{}
+	for processorName, factory := range factories {
+		processor := factory(interpreter)
+		res[fmt.Sprintf("%s/%s", processorName, name)] = processor
+	}
+
+	return res
+}