chore: check if mempool is not nil before accepting nonce gap error tx

CHANGELOG.md

@@ -10,6 +10,7 @@
 - [\#492](https://github.com/cosmos/evm/pull/492) Duplicate case switch to avoid empty execution block
 - [\#509](https://github.com/cosmos/evm/pull/509) Allow value with slashes when query token_pairs
 - [\#495](https://github.com/cosmos/evm/pull/495) Allow immediate SIGINT interrupt when mempool is not empty
+- [\#545](https://github.com/cosmos/evm/pull/545) Check if mempool is not nil before accepting nonce gap error tx.
 
 ### IMPROVEMENTS
 

rpc/backend/call_tx.go

@@ -155,7 +155,7 @@ func (b *Backend) SendRawTransaction(data hexutil.Bytes) (common.Hash, error) {
 	}
 	if err != nil {
 		// Check if this is a nonce gap error that was successfully queued
-		if strings.Contains(err.Error(), mempool.ErrNonceGap.Error()) {
+		if b.Mempool != nil && strings.Contains(err.Error(), mempool.ErrNonceGap.Error()) {
 			// Transaction was successfully queued due to nonce gap, return success to client
 			b.Logger.Debug("transaction queued due to nonce gap", "hash", txHash.Hex())
 			return txHash, nil

rpc/backend/sign_tx.go

@@ -110,7 +110,7 @@ func (b *Backend) SendTransaction(args evmtypes.TransactionArgs) (common.Hash, e
 	}
 	if err != nil {
 		// Check if this is a nonce gap error that was successfully queued
-		if strings.Contains(err.Error(), mempool.ErrNonceGap.Error()) {
+		if b.Mempool != nil && strings.Contains(err.Error(), mempool.ErrNonceGap.Error()) {
 			// Transaction was successfully queued due to nonce gap, return success to client
 			b.Logger.Debug("transaction queued due to nonce gap", "hash", txHash.Hex())
 			return txHash, nil