bug: contract.simulate does not accept feeCurrency field

[arthurgousset]

Is there an existing issue for this?

• I have searched the existing issues

Package Version

2.7.9

Current Behavior

This code snippet shows an error (red squiggly line) under feeCurrency:

const transactionSimulation = await contract.simulate.transfer(
        [cUSD_CONTRACT_ADDRESS, parseUnits("0.01", decimals)],
        { account: sender, feeCurrency: "0x874069Fa1Eb16D44d622F2e0Ca25eeA172369bC1" }
);

The error message is:

Object literal may only specify known properties, and 'feeCurrency' does not exist in type 'Omit<SimulateContractParameters<readonly ...

But the same code as contract.write.transfer accepts the feeCurrency

const transactionReceipt = await contract.write.transfer(
        [cUSD_CONTRACT_ADDRESS, parseUnits("0.01", decimals)],
        { account: sender, feeCurrency: "0x874069Fa1Eb16D44d622F2e0Ca25eeA172369bC1" }
    );

Expected Behavior

simulate and WalletClient calls should accept the same fields.

Viem recommends that most contract calls or transactions are first simulated

Warning: The write internally sends a transaction – it does not validate if the contract write will succeed (the contract may throw an error). It is highly recommended to simulate the contract write with `contract.simulate` before you execute it.

Steps To Reproduce

import {
    createPublicClient,
    createWalletClient,
    http,
    parseEther,
    parseGwei,
    Address,
    getContract,
    erc20Abi,
    parseUnits,
    formatUnits,
} from "viem";
import { privateKeyToAccount } from "viem/accounts";
import { celoAlfajores } from "viem/chains";
import {
    PRIVATE_KEY,
    RECIPIENT,
    cUSD_CONTRACT_ADDRESS,
    USDC_CONTRACT_ADDRESS,
    USDC_ADAPTER_ADDRESS,
} from "./constants";

/**
 * Boilerplate to create a viem client and viem-compatible wallet
 */
const read = createPublicClient({
    chain: celoAlfajores,
    transport: http(),
});
const write = createWalletClient({
    chain: celoAlfajores, // Celo testnet
    transport: http(),
});
const sender = privateKeyToAccount(`0x${PRIVATE_KEY}`);

/**
 *  Set up ERC20 contract
 */
const contract = getContract({
    address: cUSD_CONTRACT_ADDRESS,
    abi: erc20Abi,
    client: { public: read, wallet: write },
});
const [symbol, decimals, tokenBalance] = await Promise.all([
    contract.read.symbol(),
    contract.read.decimals(),
    contract.read.balanceOf(["0xcEe284F754E854890e311e3280b767F80797180d"]),
]);

/**
 * Makes a transaction to transfer ERC20 tokens using a fee currency
 */
async function erc20Transfer() {
    console.log(`Initiating fee currency transaction...`);
    console.log(`${symbol} balance of ${sender}: ${formatUnits(tokenBalance, decimals)}`);

    const transactionSimulation = await contract.simulate.transfer(
        [RECIPIENT, parseUnits("0.01", decimals)],
        { account: sender, feeCurrency: "0x874069Fa1Eb16D44d622F2e0Ca25eeA172369bC1" }
    );
    const transactionReceipt = await contract.write.transfer(
        [RECIPIENT, parseUnits("0.01", decimals)],
        { account: sender, feeCurrency: "0x874069Fa1Eb16D44d622F2e0Ca25eeA172369bC1" }
    );
    console.log(transactionReceipt);
}

erc20Transfer().catch((err) => {
    console.error("An error occurred:", err);
});

Link to Minimal Reproducible Example (StackBlitz, CodeSandbox, GitHub repo etc.)

https://github.com/celo-org/feecurrency/blob/main/viem.ts

Anything else?

No response

Related

• CLI and ContractKit support all accepted fee currencies equally, including for transfers and for use as fee currencies developer-tooling#128
  - celo-org/feecurrency demo repo

[arthurgousset]

This issue could be done around the same time or shortly after this:

• Add celo gas fee estimator  #4

(while you have your head in viem)

[shazarre]

Apparently it works fine if you pass the chain explicitly to the simulate transaction params:

and fails as described by @arthurgousset if you don't:

For write transaction though it seems to just accept any arbitrary parameters with the chain explicitly provided:

and without it as well: