Use the estimate function inside the package rather than going to the…

… provider.

packages/rif-relay-sdk/src/RifRelaySDK/RifRelaySDK.ts

@@ -18,10 +18,13 @@ import {
 } from './types'
 import {
   dataTypeFields,
+  filterTxOptions,
   getDomainSeparator,
+  INTERNAL_TRANSACTION_ESTIMATE_CORRECTION,
   MAX_RELAY_NONCE_GAP,
   validUntilTime,
-  ZERO_ADDRESS
+  ZERO_ADDRESS,
+  ZERO_HASH
 } from './helpers'
 import ERC20Abi from './erc20abi.json'
 
@@ -121,8 +124,18 @@ export class RIFRelaySDK {
       ? estTokenGas.toNumber() * tokenGasIncrease
       : estTokenGas
 
-    const estimated = await this.provider.estimateGas({ ...tx, gasPrice })
-    const internalCallCost = Math.round(estimated.toNumber() * 1.01)
+    // estimate the gas of the transaction:
+    const estimated = await this.smartWallet
+      .estimateDirectExecute(
+        tx.to || ZERO_ADDRESS,
+        tx.data || ZERO_HASH,
+        filterTxOptions(tx),
+      )
+
+    const internalCallCost = estimated.gt(INTERNAL_TRANSACTION_ESTIMATE_CORRECTION)
+      ? estimated.sub(INTERNAL_TRANSACTION_ESTIMATE_CORRECTION)
+      : estimated
+
     const updatedNonceWithPendingTxs = nonce.add(pendingTxsCount)
 
     const relayRequest: RelayRequest = {

packages/rif-relay-sdk/src/RifRelaySDK/helpers.ts

@@ -5,6 +5,7 @@ import {
   RelayDataType,
   RelayRequestType
 } from './types'
+import { TransactionRequest } from '@ethersproject/abstract-provider'
 
 export interface EIP712Domain {
   name?: string | undefined
@@ -31,10 +32,20 @@ export function getDomainSeparator (
   }
 }
 
+export const filterTxOptions = (transactionRequest: TransactionRequest) =>
+  Object.keys(transactionRequest)
+    .filter(key => !['from', 'to', 'data'].includes(key))
+    .reduce((obj: any, key: any) => {
+      obj[key] = (transactionRequest as any)[key]
+      return obj
+    }, {})
+
 export const validUntilTime = () => Math.floor(Date.now() / 1000) + TWO_DAYS
 
 export const MAX_RELAY_NONCE_GAP = 3
 export const ZERO_ADDRESS = '0x0000000000000000000000000000000000000000'
+export const ZERO_HASH = '0x0000000000000000000000000000000000000000000000000000000000000000'
+export const INTERNAL_TRANSACTION_ESTIMATE_CORRECTION = BigNumber.from(20000)
 export const RIF_TOKEN_ADDRESS_TESTNET =
   '0x19F64674D8A5B4E652319F5e239eFd3bc969A1fE'
 export const TWO_RIF = BigNumber.from('2000000000000000000')