fix: remove lighter fee (#119)

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Author: mpetrun5

chains/lighter/message/lighter.go

@@ -24,9 +24,8 @@ import (
 )
 
 var (
-	ARBITRUM_CHAIN_ID  = big.NewInt(42161)
-	FEE                = big.NewInt(2000000)
-	USDC_ACCOUNT_INDEX = 3
+	ARBITRUM_CHAIN_ID         = big.NewInt(42161)
+	USDC_ACCOUNT_INDEX uint64 = 3
 )
 
 type Coordinator interface {
@@ -146,24 +145,19 @@ func (h *LighterMessageHandler) verifyWithdrawal(tx *lighter.LighterTx) error {
 		return errors.New("transfer account index invalid")
 	}
 
-	if tx.Transfer.AssetIndex != uint64(USDC_ACCOUNT_INDEX) {
+	if tx.Transfer.AssetIndex != USDC_ACCOUNT_INDEX {
 		return errors.New("only usdc asset supported on lighter")
 	}
 
-	if tx.Transfer.Amount <= FEE.Uint64() {
-		return errors.New("fee higher than withdrawal amount")
-	}
-
 	return nil
 }
 
 func (h *LighterMessageHandler) calldata(tx *lighter.LighterTx) ([]byte, error) {
-	borrowAmount := new(big.Int).Sub(new(big.Int).SetUint64(tx.Transfer.Amount), FEE)
 	return consts.LighterABI.Pack(
 		"fulfillWithdraw",
 		common.HexToHash(tx.Hash),
 		common.BytesToAddress(tx.Transfer.Memo[:20]),
-		borrowAmount)
+		new(big.Int).SetUint64(tx.Transfer.Amount))
 }
 
 func (h *LighterMessageHandler) Listen(ctx context.Context) {

chains/lighter/message/lighter_test.go

@@ -112,49 +112,6 @@ func (s *LighterMessageHandlerTestSuite) Test_HandleMessage_ValidMessage() {
 	s.Nil(err)
 }
 
-func (s *LighterMessageHandlerTestSuite) Test_HandleMessage_FeeHigherThanAmount() {
-	s.mockCommunication.EXPECT().Broadcast(
-		gomock.Any(),
-		gomock.Any(),
-		comm.LighterMsg,
-		"lighter",
-	).Return(nil)
-	p, _ := pstoremem.NewPeerstore()
-	s.mockHost.EXPECT().Peerstore().Return(p)
-
-	errChn := make(chan error, 1)
-	ad := &message.LighterData{
-		ErrChn:        errChn,
-		Nonce:         big.NewInt(101),
-		LiquidityPool: common.HexToAddress("0xbe526bA5d1ad94cC59D7A79d99A59F607d31A657"),
-		OrderHash:     "orderHash",
-		DepositTxHash: "orderHash",
-	}
-
-	s.mockTxFetcher.EXPECT().GetTx(ad.OrderHash).Return(&lighter.LighterTx{
-		Type: lighter.TxTypeL2Transfer,
-		Transfer: &lighter.Transfer{
-			Amount:         2000000,
-			AssetIndex:     3,
-			ToAccountIndex: 3,
-			Memo:           []byte{238, 123, 250, 212, 202, 237, 62, 98, 106, 248, 169, 199, 213, 3, 76, 213, 137, 238, 73, 144, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
-		},
-	}, nil)
-
-	m := &coreMessage.Message{
-		Data:        ad,
-		Source:      0,
-		Destination: 10,
-	}
-	prop, err := s.handler.HandleMessage(m)
-
-	s.Nil(prop)
-	s.NotNil(err)
-
-	err = <-errChn
-	s.NotNil(err)
-}
-
 func (s *LighterMessageHandlerTestSuite) Test_HandleMessage_InvalidTxType() {
 	s.mockCommunication.EXPECT().Broadcast(
 		gomock.Any(),