I am running this code and have just seen this error appear.
import { ethers } from 'ethers'
import { getMulticallContract } from 'utils/contractHelpers'
import { MultiCallResponse } from './types'
export interface Call {
address: string // Address of the contract
name: string // Function name on the contract (example: balanceOf)
params?: any[] // Function params
}
interface MulticallOptions {
requireSuccess?: boolean
}
const multicall = async <T = any>(abi: any[], calls: Call[]): Promise<T> => {
try {
const multi = getMulticallContract()
const itf = new ethers.utils.Interface(abi)
const calldata = calls.map((call) => [call.address.toLowerCase(), itf.encodeFunctionData(call.name, call.params)])
const { returnData } = await multi.aggregate(calldata)
const res = returnData.map((call, i) => itf.decodeFunctionResult(calls[i].name, call))
return res
} catch (error) {
throw new Error(error)
}
}
This is the error that I'm getting, although until now this has been running just fine.
Argument of type 'unknown' is not assignable to parameter of type 'string'. TS2345
28 | return res
29 | } catch (error) {
> 30 | throw new Error(error)
| ^
31 | }
32 | }
33 |
I've looked through related questions, but can't see any exact solution in this case, but also I'm learning typescript currently.
In the end I just added "useUnknownInCatchVariables": false, to tsconfig and it stopped errors from being converted to unknown, which is what was causing this issue.
I believe I have to upgrade typescript as well though, because there is a warning in tsconfig about this flag Unknown compiler option 'useUnknownInCatchVariables'.
Also see that another solution to this is mentioned in the docs: https://www.typescriptlang.org/tsconfig#useUnknownInCatchVariables
try {
// ...
} catch (err) {
// We have to verify err is an
// error before using it as one.
if (err instanceof Error) {
console.log(err.message);
}
}
unknown), and new Error() receives a stringBased on the context of your multicall function, I would suggest that you put a meaningful string to that error (which production-grade web usually do)
You would throw something like this:
const multicall = async <T = any>(abi: any[], calls: Call[]): Promise<T> => {
try {
const multi = getMulticallContract();
const itf = new ethers.utils.Interface(abi);
const calldata = calls.map((call) => [
call.address.toLowerCase(),
itf.encodeFunctionData(call.name, call.params),
]);
const { returnData } = await multi.aggregate(calldata);
const res = returnData.map((call, i) => itf.decodeFunctionResult(calls[i].name, call));
return res;
} catch {
throw new Error('something went wrong in the multical function');
}
};