Can't decode name when it's a bytes32 instead of a string

[feloot]

Ethers Version

6.6.2

Search Terms

bytes name symbol erc20

Describe the Problem

I'm trying to interact with the Maker token contract on Ethereum with address : 0x9f8F72aA9304c8B593d555F12eF6589cC3A579A2

Most tokens use strings for their names and symbols but this contract uses a bytes32 variable.

I have changed the ABI to reflect the new type but Ethers throws an error when calling name() or symbol() and I'm not able to process the data.

Code Snippet

const contract = new ethers.Contract(
      contractAddress,
      abi,
      signer
    )

const erc = contract.connect(walletAddress)

const name = await contract.name() // throws the error

Contract ABI

{
  "_format": "hh-sol-artifact-1",
  "contractName": "IERC20",
  "sourceName": "contracts/interfaces/IERC20.sol",
  "abi": [
    {
      "anonymous": false,
      "inputs": [
        {
          "indexed": true,
          "internalType": "address",
          "name": "owner",
          "type": "address"
        },
        {
          "indexed": true,
          "internalType": "address",
          "name": "spender",
          "type": "address"
        },
        {
          "indexed": false,
          "internalType": "uint256",
          "name": "value",
          "type": "uint256"
        }
      ],
      "name": "Approval",
      "type": "event"
    },
    {
      "anonymous": false,
      "inputs": [
        {
          "indexed": true,
          "internalType": "address",
          "name": "from",
          "type": "address"
        },
        {
          "indexed": true,
          "internalType": "address",
          "name": "to",
          "type": "address"
        },
        {
          "indexed": false,
          "internalType": "uint256",
          "name": "value",
          "type": "uint256"
        }
      ],
      "name": "Transfer",
      "type": "event"
    },
    {
      "inputs": [
        {
          "internalType": "address",
          "name": "owner",
          "type": "address"
        },
        {
          "internalType": "address",
          "name": "spender",
          "type": "address"
        }
      ],
      "name": "allowance",
      "outputs": [
        {
          "internalType": "uint256",
          "name": "",
          "type": "uint256"
        }
      ],
      "stateMutability": "view",
      "type": "function"
    },
    {
      "inputs": [
        {
          "internalType": "address",
          "name": "spender",
          "type": "address"
        },
        {
          "internalType": "uint256",
          "name": "value",
          "type": "uint256"
        }
      ],
      "name": "approve",
      "outputs": [
        {
          "internalType": "bool",
          "name": "",
          "type": "bool"
        }
      ],
      "stateMutability": "nonpayable",
      "type": "function"
    },
    {
      "inputs": [
        {
          "internalType": "address",
          "name": "owner",
          "type": "address"
        }
      ],
      "name": "balanceOf",
      "outputs": [
        {
          "internalType": "uint256",
          "name": "",
          "type": "uint256"
        }
      ],
      "stateMutability": "view",
      "type": "function"
    },
    {
      "inputs": [],
      "name": "decimals",
      "outputs": [
        {
          "internalType": "uint8",
          "name": "",
          "type": "uint8"
        }
      ],
      "stateMutability": "view",
      "type": "function"
    },
    {
      "inputs": [],
      "name": "name",
      "outputs": [
        {
          "internalType": "bytes",
          "name": "",
          "type": "bytes"
        }
      ],
      "stateMutability": "view",
      "type": "function"
    },
    {
      "inputs": [],
      "name": "symbol",
      "outputs": [
        {
          "internalType": "bytes",
          "name": "",
          "type": "bytes"
        }
      ],
      "stateMutability": "view",
      "type": "function"
    },
    {
      "inputs": [],
      "name": "totalSupply",
      "outputs": [
        {
          "internalType": "uint256",
          "name": "",
          "type": "uint256"
        }
      ],
      "stateMutability": "view",
      "type": "function"
    },
    {
      "inputs": [
        {
          "internalType": "address",
          "name": "to",
          "type": "address"
        },
        {
          "internalType": "uint256",
          "name": "value",
          "type": "uint256"
        }
      ],
      "name": "transfer",
      "outputs": [
        {
          "internalType": "bool",
          "name": "",
          "type": "bool"
        }
      ],
      "stateMutability": "nonpayable",
      "type": "function"
    },
    {
      "inputs": [
        {
          "internalType": "address",
          "name": "from",
          "type": "address"
        },
        {
          "internalType": "address",
          "name": "to",
          "type": "address"
        },
        {
          "internalType": "uint256",
          "name": "value",
          "type": "uint256"
        }
      ],
      "name": "transferFrom",
      "outputs": [
        {
          "internalType": "bool",
          "name": "",
          "type": "bool"
        }
      ],
      "stateMutability": "nonpayable",
      "type": "function"
    }
  ],
  "bytecode": "0x",
  "deployedBytecode": "0x",
  "linkReferences": {},
  "deployedLinkReferences": {}
}

Errors

Error: could not decode result data (value="0x4d616b6572000000000000000000000000000000000000000000000000000000", info={ "method": "name", "signature": "name()" }, code=BAD_DATA, version=6.6.1)
    at makeError (errors.ts:677:21)
    at assert (errors.ts:694:25)
    at _Interface.decodeFunctionResult (interface.ts:916:9)
    at staticCallResult (contract.ts:324:35)
    at async staticCall (contract.ts:281:24)
    at async Proxy.name (contract.ts:329:41)

Environment

Ethereum (mainnet/ropsten/rinkeby/goerli)

Environment (Other)

No response

[zemse]

From the ABI it appears that bytes type is being used for name and symbol, while you need bytes32 there.

function name() public returns (bytes32);
function symbol() public returns (bytes32);

Then you can use ethers.decodeBytes32String util to process it.

[ricmoo]

I believe this is probably correct, if you can try it out and if so, mark it as the accepted answer? :)

[fukemy]

hello, can you help me about the function balanceOf? I got same error like this:

const USDTAbi = [
  'function name() view returns (string)',
  'function symbol() view returns (string)',
  'function balanceOf(address) view returns (uint)',
  'function transfer(address to, uint amount)',
  'event Transfer(address indexed from, address indexed to, uint amount)'
]

const ethersProvider = new BrowserProvider(walletProvider)
    const signer = await ethersProvider.getSigner()
    const USDTContract = new Contract(USDTAddress, USDTAbi, signer)
    const USDTBalance = await USDTContract.balanceOf(address)
    console.log(formatUnits(USDTBalance, 18))

here is the error:

Error: could not decode result data (value="0x", info={ "method": "balanceOf", "signature": "balanceOf(address)" }, code=BAD_DATA, version=6.13.2)
    at makeError (errors.js:137:21)
    at assert (errors.js:156:15)
    at Interface.decodeFunctionResult (interface.js:792:64)
    at staticCallResult (contract.js:265:35)
    at async staticCall (contract.js:230:24)
    at async Proxy.balanceOf (contract.js:270:20)
    at async getBalance (page.js:45:25)

[zemse]

value="0x"

Seems result of eth_call is empty data. Probably the contract is an empty account, this could be caused due to incorrect address or network.

[feloot]

Thanks a lot, that was it ! It's working perfectly now.