fix: hardcode gas limit for smart contract claimer (#202)

* fix: hardcode gas limit for smart contract claimer

* comments

pkg/internal/common/eth.go

@@ -24,11 +24,11 @@ type TxFeeDetails struct {
 }
 
 func (t *TxFeeDetails) Print() {
-	message := strings.Repeat("-", 25) + " Gas Fee Details " + strings.Repeat("-", 25)
+	message := strings.Repeat("-", 30) + " Gas Fee Details " + strings.Repeat("-", 30)
 	fmt.Println(message)
 	fmt.Printf("Gas Tip Cap: %0.9f Gwei\n", t.GasTipCapGwei)
 	fmt.Printf("Gas Fee Cap: %0.9f Gwei\n", t.GasFeeCapGwei)
-	fmt.Printf("Gas Limit: %d\n", t.GasLimit)
+	fmt.Printf("Gas Limit: %d (If claimer is a smart contract, this value is hardcoded)\n", t.GasLimit)
 	fmt.Printf("Approximate Max Cost of transaction: %0.12f ETH\n", t.CostInEth)
 	fmt.Println(strings.Repeat("-", len(message)))
 }

pkg/rewards/claim.go

@@ -204,10 +204,24 @@ func Claim(cCtx *cli.Context, p utils.Prompter) error {
 			return err
 		}
 
+		// If claimer is a smart contract, we can't estimate gas using geth
+		// since balance of contract can be 0, as it can be called by an EOA
+		// to claim. So we hardcode the gas limit to 150_000 so that we can
+		// create unsigned tx without gas limit estimation from contract bindings
+		code, err := ethClient.CodeAt(ctx, config.ClaimerAddress, nil)
+		if err != nil {
+			return eigenSdkUtils.WrapError("failed to get code at address", err)
+		}
+		if len(code) > 0 {
+			// Claimer is a smart contract
+			noSendTxOpts.GasLimit = 150_000
+		}
+
 		unsignedTx, err := contractBindings.RewardsCoordinator.ProcessClaim(noSendTxOpts, elClaim, config.RecipientAddress)
 		if err != nil {
 			return eigenSdkUtils.WrapError("failed to create unsigned tx", err)
 		}
+
 		if config.OutputType == string(common.OutputType_Calldata) {
 			calldataHex := gethcommon.Bytes2Hex(unsignedTx.Data())