Omit ethCompatible on RPC responses for non legacy txs (#2302)

* Omit ethCompatible on RPC responses for non legacy txs

* feat(ethapi): omits additional fields when empty

Omits `feeCurrency`, `gatewayFeeRecipient`, and `gatewayFee` from the response when they are empty (effectively on Ethereum-compatible transactions).

When I call `eth_gasTransactionByHash` on an EIP-1559 transaction, the response object includes `feeCurrency`, `gatewayFeeRecipient`, and `gatewayFee` although they aren't relevant.

* Update monorepo_commit (GatewayFeeRecipient check)

to include celo-org/celo-monorepo@a63f0ec

---------

Co-authored-by: arthurgousset <[email protected]>
Co-authored-by: Karl Bartel <[email protected]>

internal/ethapi/api.go

@@ -1288,9 +1288,9 @@ type RPCTransaction struct {
 	GasPrice            *hexutil.Big      `json:"gasPrice"`
 	GasFeeCap           *hexutil.Big      `json:"maxFeePerGas,omitempty"`
 	GasTipCap           *hexutil.Big      `json:"maxPriorityFeePerGas,omitempty"`
-	FeeCurrency         *common.Address   `json:"feeCurrency"`
-	GatewayFeeRecipient *common.Address   `json:"gatewayFeeRecipient"`
-	GatewayFee          *hexutil.Big      `json:"gatewayFee"`
+	FeeCurrency         *common.Address   `json:"feeCurrency,omitempty"`
+	GatewayFeeRecipient *common.Address   `json:"gatewayFeeRecipient,omitempty"`
+	GatewayFee          *hexutil.Big      `json:"gatewayFee,omitempty"`
 	Hash                common.Hash       `json:"hash"`
 	Input               hexutil.Bytes     `json:"input"`
 	Nonce               hexutil.Uint64    `json:"nonce"`
@@ -1303,7 +1303,7 @@ type RPCTransaction struct {
 	V                   *hexutil.Big      `json:"v"`
 	R                   *hexutil.Big      `json:"r"`
 	S                   *hexutil.Big      `json:"s"`
-	EthCompatible       bool              `json:"ethCompatible"`
+	EthCompatible       *bool             `json:"ethCompatible,omitempty"`
 }
 
 // newRPCTransaction returns a transaction that will serialize to the RPC
@@ -1341,7 +1341,11 @@ func newRPCTransaction(tx *types.Transaction, blockHash common.Hash, blockNumber
 		V:                   (*hexutil.Big)(v),
 		R:                   (*hexutil.Big)(r),
 		S:                   (*hexutil.Big)(s),
-		EthCompatible:       tx.EthCompatible(),
+	}
+	// Set eth compatible for legacy transactions only
+	if tx.Type() == types.LegacyTxType {
+		ec := tx.EthCompatible()
+		result.EthCompatible = &ec
 	}
 	if blockHash != (common.Hash{}) {
 		result.BlockHash = &blockHash

internal/ethapi/api_test.go

@@ -1,14 +1,17 @@
 package ethapi
 
 import (
+	"encoding/json"
 	"errors"
+	"fmt"
 	"math/big"
 	"testing"
 
 	"github.com/celo-org/celo-blockchain/common"
 	"github.com/celo-org/celo-blockchain/common/hexutil"
 	"github.com/celo-org/celo-blockchain/core/types"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 // TestNewRPCTransactionCeloDynamicV2 tests the newRPCTransaction method with a celo dynamic fee tx v2 type.
@@ -159,3 +162,42 @@ func TestNewRPCTransactionDynamic(t *testing.T) {
 		assert.Equal(t, (*hexutil.Big)(bigFeeCap), rpcTx.GasPrice)
 	})
 }
+
+// TestNewRPCTransactionEthCompatible tests that only legacy transactions have the eth compatbile field set.
+func TestNewRPCTransactionEthCompatible(t *testing.T) {
+	blockHash := common.BigToHash(big.NewInt(123456))
+	blockNumber := uint64(123456)
+	index := uint64(7)
+	baseFeeFn := func(curr *common.Address) (*big.Int, error) {
+		return big.NewInt(600), nil
+	}
+
+	t.Run("LegacyTx ethCompatible", func(*testing.T) {
+		rpcTx := newRPCTransaction(types.NewTx(&types.LegacyTx{
+			EthCompatible: true,
+		}), blockHash, blockNumber, index, baseFeeFn, true)
+		assert.Equal(t, true, jsonRoundtripToMap(t, rpcTx)["ethCompatible"])
+	})
+
+	t.Run("LegacyTx not ethCompatible", func(*testing.T) {
+		rpcTx := newRPCTransaction(types.NewTx(&types.LegacyTx{
+			EthCompatible: false,
+		}), blockHash, blockNumber, index, baseFeeFn, true)
+		assert.Equal(t, false, jsonRoundtripToMap(t, rpcTx)["ethCompatible"])
+	})
+
+	t.Run("Non legacy tx ethCompatible not set", func(*testing.T) {
+		rpcTx := newRPCTransaction(types.NewTx(&types.DynamicFeeTx{}), blockHash, blockNumber, index, baseFeeFn, true)
+		assert.NotContains(t, jsonRoundtripToMap(t, rpcTx), "ethCompatible")
+		fmt.Printf("%+v\n", jsonRoundtripToMap(t, rpcTx))
+	})
+}
+
+func jsonRoundtripToMap(t *testing.T, tx *RPCTransaction) map[string]interface{} {
+	marshaled, err := json.Marshal(tx)
+	require.NoError(t, err)
+	m := make(map[string]interface{})
+	err = json.Unmarshal(marshaled, &m)
+	require.NoError(t, err)
+	return m
+}

monorepo_commit

@@ -1 +1 @@
-f08e269d88c6680641427952ce4743a7d26336a6
+a63f0ec01ecd52b35dd01554eff22337e183da40