From 8d514000cf38b0a94c61ce7b54a4818e4959bd46 Mon Sep 17 00:00:00 2001
From: Eric Warehime <eric.warehime@gmail.com>
Date: Tue, 19 Dec 2023 11:05:19 -0800
Subject: [PATCH] test: Add test for free tx lane (#305)

---
 tests/integration/network/network_test.go | 58 +++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/tests/integration/network/network_test.go b/tests/integration/network/network_test.go
index 046b7f4..0ae07ab 100644
--- a/tests/integration/network/network_test.go
+++ b/tests/integration/network/network_test.go
@@ -5,6 +5,15 @@ import (
 	"fmt"
 	"testing"
 
+	"github.com/skip-mev/chaintestutil/network"
+
+	banktypes "github.com/cosmos/cosmos-sdk/x/bank/types"
+
+	"cosmossdk.io/math"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	stakingtypes "github.com/cosmos/cosmos-sdk/x/staking/types"
+
 	tmcli "github.com/cometbft/cometbft/libs/cli"
 	"github.com/stretchr/testify/require"
 	"github.com/stretchr/testify/suite"
@@ -114,3 +123,52 @@ func (s *NetworkTestSuite) QueryBlockSDKLanes() (*blocksdktypes.QueryLanesRespon
 	client := blocksdktypes.NewQueryClient(cc)
 	return client.Lanes(context.Background(), &blocksdktypes.QueryLanesRequest{})
 }
+
+func (s *NetworkTestSuite) TestFreeTxNoFees() {
+	val := s.NetworkSuite.Network.Validators[0]
+	acc := *s.Accounts[0]
+
+	cc, closeConn, err := s.NetworkSuite.GetGRPC()
+	s.Require().NoError(err)
+	defer closeConn()
+
+	// Get original acc balance
+	bankClient := banktypes.NewQueryClient(cc)
+	resp, err := bankClient.Balance(context.Background(), &banktypes.QueryBalanceRequest{
+		Address: acc.Address().String(),
+		Denom:   s.NetworkSuite.Network.Config.BondDenom,
+	})
+	require.NoError(s.T(), err)
+	originalBalance := resp.Balance.Amount
+
+	// Send a free tx (delegation)
+	coin := sdk.NewCoin(s.NetworkSuite.Network.Config.BondDenom, math.NewInt(10))
+	txBz, err := s.NetworkSuite.CreateTxBytes(
+		context.Background(),
+		network.TxGenInfo{
+			Account:       acc,
+			GasLimit:      999999999,
+			TimeoutHeight: 999999999,
+			Fee:           sdk.NewCoins(coin),
+		},
+		&stakingtypes.MsgDelegate{
+			DelegatorAddress: acc.Address().String(),
+			ValidatorAddress: val.ValAddress.String(),
+			Amount:           coin,
+		},
+	)
+	require.NoError(s.T(), err)
+	bcastResp, err := val.RPCClient.BroadcastTxCommit(context.Background(), txBz)
+	require.NoError(s.T(), err)
+	require.Equal(s.T(), uint32(0), bcastResp.CheckTx.Code)
+	require.Equal(s.T(), uint32(0), bcastResp.TxResult.Code)
+
+	// Get updated acc balance
+	resp, err = bankClient.Balance(context.Background(), &banktypes.QueryBalanceRequest{
+		Address: acc.Address().String(),
+		Denom:   s.NetworkSuite.Network.Config.BondDenom,
+	})
+	require.NoError(s.T(), err)
+	// Assert update acc balance is equal to original balance less the delegation
+	require.Equal(s.T(), originalBalance.Sub(coin.Amount), resp.Balance.Amount)
+}