Should client.multicall validate that functionNames are in the ABI?

[hammeiam]

I really love how contract instances and things like getAbiItem will both suggest names from the ABI and complain when you don't use a proper name. I was wondering if the multicall function should do the same. Thanks!

[tmm]

It should already do that! Have an example? Works fine in this TypeScript Playground.

[hammeiam]

I sure do! One image is of createEventFilter correctly alerting me to an invalid event name. The other is of multicall allowing me to pass a clearly invalid function name.

[tmm]

This is a limitation of TypeScript at the moment and how it handles higher-order functions. See microsoft/TypeScript#29841 Workaround is to cast each mapped value using ContractFunctionConfig:

import type { ContractFunctionConfig } from 'viem'

const res = await publicClient.multicall({
  allowFailure: false,
  contracts: tokenAddresses.map(
    (x) =>
      ({
        address: x,
        abi: erc20Abi,
        functionName: 'balanceOf',
        args: ['0x'],
      } as ContractFunctionConfig<
        typeof erc20Abi,
        'balanceOf',
        'pure' | 'view'
      >),
  ),
})

TypeScript Playground