fix: stuck escrow fees

app/app.go

@@ -1026,6 +1026,7 @@ func (app *App) setAnteHandler(txConfig client.TxConfig, wasmConfig wasmtypes.Wa
 
 func (app *App) setPostHandler() {
 	postHandler := PostHandlerOptions{
+		AccountKeeper:   app.AccountKeeper,
 		BankKeeper:      app.BankKeeper,
 		FeeMarketKeeper: app.FeeMarketKeeper,
 	}

app/post_handler.go

@@ -9,12 +9,17 @@ import (
 
 // PostHandlerOptions are the options required for constructing a FeeMarket PostHandler.
 type PostHandlerOptions struct {
+	AccountKeeper   xfeemarketpost.AccountKeeper
 	BankKeeper      xfeemarketpost.BankKeeper
 	FeeMarketKeeper xfeemarketpost.FeeMarketKeeper
 }
 
 // NewPostHandler returns a PostHandler chain with the fee deduct decorator.
 func NewPostHandler(options PostHandlerOptions) (sdk.PostHandler, error) {
+	if options.AccountKeeper == nil {
+		return nil, errorsmod.Wrap(sdkerrors.ErrLogic, "account keeper is required for post builder")
+	}
+
 	if options.BankKeeper == nil {
 		return nil, errorsmod.Wrap(sdkerrors.ErrLogic, "bank keeper is required for post builder")
 	}
@@ -25,6 +30,7 @@ func NewPostHandler(options PostHandlerOptions) (sdk.PostHandler, error) {
 
 	postDecorators := []sdk.PostDecorator{
 		xfeemarketpost.NewFeeMarketDeductDecorator(
+			options.AccountKeeper,
 			options.BankKeeper,
 			options.FeeMarketKeeper,
 		),

x/xfeemarket/post/expected_keepers.go

@@ -1,11 +1,21 @@
 package post
 
 import (
+	"context"
+
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	bankkeeper "github.com/cosmos/cosmos-sdk/x/bank/keeper"
 	feemarkettypes "github.com/skip-mev/feemarket/x/feemarket/types"
 )
 
+// AccountKeeper defines the contract needed for AccountKeeper related APIs.
+// Interface provides support to use non-sdk AccountKeeper for AnteHandler's decorators.
+//
+//go:generate mockery --name AccountKeeper --filename mock_account_keeper.go
+type AccountKeeper interface {
+	GetModuleAccount(ctx context.Context, name string) sdk.ModuleAccountI
+}
+
 // BankKeeper defines the contract needed for supply related APIs.
 //
 //go:generate mockery --name BankKeeper --filename mock_bank_keeper.go

x/xfeemarket/post/fee.go

@@ -21,12 +21,14 @@ const BankSendGasConsumption = 12490 + 37325
 // Call next PostHandler if fees successfully deducted.
 // CONTRACT: Tx must implement FeeTx interface
 type FeeMarketDeductDecorator struct {
+	accountKeeper   AccountKeeper
 	bankKeeper      BankKeeper
 	feemarketKeeper FeeMarketKeeper
 }
 
-func NewFeeMarketDeductDecorator(bk BankKeeper, fmk FeeMarketKeeper) FeeMarketDeductDecorator {
+func NewFeeMarketDeductDecorator(ak AccountKeeper, bk BankKeeper, fmk FeeMarketKeeper) FeeMarketDeductDecorator {
 	return FeeMarketDeductDecorator{
+		accountKeeper:   ak,
 		bankKeeper:      bk,
 		feemarketKeeper: fmk,
 	}
@@ -148,19 +150,6 @@ func (dfd FeeMarketDeductDecorator) PostHandle(ctx sdk.Context, tx sdk.Tx, simul
 func (dfd FeeMarketDeductDecorator) BurnFeeAndRefund(ctx sdk.Context, fee, tip sdk.Coin, feePayer sdk.AccAddress, defaultFeeDenom string) error {
 	var events sdk.Events
 
-	// burn the fees if it is the default fee denom
-	if !fee.IsNil() && !fee.IsZero() && fee.Denom == defaultFeeDenom {
-		err := BurnCoins(dfd.bankKeeper, ctx, sdk.NewCoins(fee))
-		if err != nil {
-			return err
-		}
-
-		events = append(events, sdk.NewEvent(
-			feemarkettypes.EventTypeFeePay,
-			sdk.NewAttribute(sdk.AttributeKeyFee, fee.String()),
-		))
-	}
-
 	// refund the tip if it is not nil and non zero
 	if !tip.IsNil() && !tip.IsZero() {
 		err := RefundTip(dfd.bankKeeper, ctx, feePayer, sdk.NewCoins(tip))
@@ -175,6 +164,35 @@ func (dfd FeeMarketDeductDecorator) BurnFeeAndRefund(ctx sdk.Context, fee, tip s
 		))
 	}
 
+	// fees from previous transactions may be stuck in escrow if transaction is out of gas
+	// burn both the fee and the stuck escrowed fees
+	feemarketCollector := dfd.accountKeeper.GetModuleAccount(ctx, feemarkettypes.FeeCollectorName)
+	burnCoin := dfd.bankKeeper.GetBalance(ctx, feemarketCollector.GetAddress(), defaultFeeDenom)
+	stuckEscrowedFee := sdk.NewCoin(defaultFeeDenom, math.ZeroInt())
+	if fee.Denom == defaultFeeDenom && burnCoin.Amount.GT(fee.Amount) {
+		stuckEscrowedFee = burnCoin.Sub(fee)
+	}
+	if burnCoin.IsPositive() {
+		err := BurnCoins(dfd.bankKeeper, ctx, sdk.NewCoins(burnCoin))
+		if err != nil {
+			return err
+		}
+
+		if !fee.IsNil() && !fee.IsZero() && fee.Denom == defaultFeeDenom {
+			events = append(events, sdk.NewEvent(
+				feemarkettypes.EventTypeFeePay,
+				sdk.NewAttribute(sdk.AttributeKeyFee, fee.String()),
+			))
+		}
+
+		if stuckEscrowedFee.IsPositive() {
+			events = append(events, sdk.NewEvent(
+				xfeemarkettypes.EventTypeBurnStuckEscrowedFee,
+				sdk.NewAttribute(sdk.AttributeKeyFee, stuckEscrowedFee.String()),
+			))
+		}
+	}
+
 	ctx.EventManager().EmitEvents(events)
 	return nil
 }

x/xfeemarket/post/fee_test.go

@@ -134,11 +134,12 @@ func TestPostHandleMock(t *testing.T) {
 	const (
 		baseDenom              = "stake"
 		resolvableDenom        = "atom"
-		expectedConsumedGas    = 9307
+		expectedConsumedGas    = 25250
 		expectedConsumedSimGas = expectedConsumedGas + post.BankSendGasConsumption
 		gasLimit               = expectedConsumedSimGas // 152800 12490 + 36385
 	)
 
+	zeroInt := math.ZeroInt()
 	validFeeAmount := types.DefaultMinBaseGasPrice.MulInt64(int64(gasLimit))
 	validFee := sdk.NewCoins(sdk.NewCoin(baseDenom, validFeeAmount.TruncateInt()))
 	validResolvableFee := sdk.NewCoins(sdk.NewCoin(resolvableDenom, validFeeAmount.TruncateInt()))
@@ -208,6 +209,7 @@ func TestPostHandleMock(t *testing.T) {
 				accs := s.CreateTestAccounts(1)
 				s.MockBankKeeper.On("SendCoinsFromAccountToModule", mock.Anything, accs[0].Account.GetAddress(),
 					types.FeeCollectorName, mock.Anything).Return(nil).Once()
+				s.MockBankKeeper.On("GetBalance", mock.Anything, mock.Anything, mock.Anything).Return(sdk.NewCoin(baseDenom, zeroInt)).Once()
 
 				return postsuite.TestCaseArgs{
 					Msgs:      []sdk.Msg{testdata.NewTestMsg(accs[0].Account.GetAddress())},
@@ -229,7 +231,7 @@ func TestPostHandleMock(t *testing.T) {
 				accs := s.CreateTestAccounts(1)
 				s.MockBankKeeper.On("SendCoinsFromAccountToModule", mock.Anything, accs[0].Account.GetAddress(),
 					types.FeeCollectorName, mock.Anything).Return(nil)
-				s.MockBankKeeper.On("BurnCoins", mock.Anything, types.FeeCollectorName, mock.Anything).Return(nil).Once()
+				s.MockBankKeeper.On("GetBalance", mock.Anything, mock.Anything, mock.Anything).Return(sdk.NewCoin(baseDenom, zeroInt)).Once()
 				s.MockBankKeeper.On("SendCoinsFromModuleToAccount", mock.Anything, types.FeeCollectorName,
 					accs[0].Account.GetAddress(), mock.Anything).Return(nil).Once()
 				return postsuite.TestCaseArgs{
@@ -296,6 +298,7 @@ func TestPostHandleMock(t *testing.T) {
 				accs := s.CreateTestAccounts(1)
 				s.MockBankKeeper.On("SendCoinsFromAccountToModule", mock.Anything, accs[0].Account.GetAddress(),
 					types.FeeCollectorName, mock.Anything).Return(nil).Once()
+				s.MockBankKeeper.On("GetBalance", mock.Anything, mock.Anything, mock.Anything).Return(sdk.NewCoin(baseDenom, zeroInt)).Once()
 				s.MockBankKeeper.On("SendCoinsFromModuleToAccount", mock.Anything, types.FeeCollectorName,
 					accs[0].Account.GetAddress(), mock.Anything).Return(nil).Once()
 
@@ -319,6 +322,7 @@ func TestPostHandleMock(t *testing.T) {
 				accs := s.CreateTestAccounts(1)
 				s.MockBankKeeper.On("SendCoinsFromAccountToModule", mock.Anything, accs[0].Account.GetAddress(),
 					types.FeeCollectorName, mock.Anything).Return(nil).Once()
+				s.MockBankKeeper.On("GetBalance", mock.Anything, mock.Anything, mock.Anything).Return(sdk.NewCoin(baseDenom, zeroInt)).Once()
 
 				return postsuite.TestCaseArgs{
 					Msgs:      []sdk.Msg{testdata.NewTestMsg(accs[0].Account.GetAddress())},
@@ -428,9 +432,9 @@ func TestPostHandle(t *testing.T) {
 	const (
 		baseDenom           = "stake"
 		resolvableDenom     = "atom"
-		expectedConsumedGas = 59122
+		expectedConsumedGas = 61632
 
-		expectedConsumedGasResolve = 25360 // slight difference due to denom resolver
+		expectedConsumedGasResolve = 27870 // slight difference due to denom resolver
 
 		gasLimit = 100000
 	)
@@ -536,7 +540,7 @@ func TestPostHandle(t *testing.T) {
 			Simulate:          false,
 			ExpPass:           true,
 			ExpErr:            nil,
-			ExpectConsumedGas: 34836,
+			ExpectConsumedGas: 37325,
 			Mock:              false,
 		},
 		{

x/xfeemarket/post/suite/suite.go

@@ -134,6 +134,7 @@ func SetupTestSuite(t *testing.T, mock bool) *TestSuite {
 }
 
 func (s *TestSuite) SetupHandlers(mock bool) {
+	accountkeeper := s.AccountKeeper
 	bankKeeper := s.BankKeeper
 	feeGrantKeeper := s.FeeGrantKeeper
 
@@ -165,6 +166,7 @@ func (s *TestSuite) SetupHandlers(mock bool) {
 	// create basic postHandler with the feemarket decorator
 	postDecorators := []sdk.PostDecorator{
 		feemarketpost.NewFeeMarketDeductDecorator(
+			accountkeeper,
 			bankKeeper,
 			s.FeeMarketKeeper,
 		),

x/xfeemarket/types/keys.go

@@ -17,7 +17,8 @@ var (
 	ParamsKey             = collections.NewPrefix("p_xfeemarket")
 	PrefixDenomMultiplier = []byte{0x01}
 
-	EventTypeTipRefund = "tip_refund"
+	EventTypeTipRefund            = "tip_refund"
+	EventTypeBurnStuckEscrowedFee = "burn_stuck_escrowed_fee"
 )
 
 func KeyPrefix(p string) []byte {