bug: type not inferred with useContractReads

[Max-3-7]

Is there an existing issue for this?

• I have searched the existing issues

Package Version

1.0.2

Current Behavior

Hey guys,

I'm upgrading to wagmi v1 but I'm having issues with type inference when using useContractReads (it works fine with wagmi <v1).

Here's a simple example that is no longer working:

import { useContractReads, erc20ABI } from 'wagmi'

// an array of ERC20 addresses on mainnet
const addresses = [
    '0x5A98FcBEA516Cf06857215779Fd812CA3beF1B32',
    '0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2'
]

const contracts = addresses.map((address) => {
    return {
        abi: erc20ABI,
        address: getAddress(address)
    } as const
})

// fetch decimals, symbol and name for all tokens
const { data, isLoading } = useContractReads({
    contracts: [
        ...contracts.map((contract) => ({
        ...contract,
        functionName: 'decimals'
    })),
        ...contracts.map((contract) => ({
        ...contract,
        functionName: 'symbol'
    })),
        ...contracts.map((contract) => ({
        ...contract,
        functionName: 'name'
    }))
  ]
})

The result is of type unknown :

const data: ({
    error: Error;
    result?: undefined;
    status: "failure";
} | {
    error?: undefined;
    result: unknown;
    status: "success";
})[] | undefined

Most of the useContractReads no longer inferring the data type correctly, although there is a few of them that still works.

Let me know if you have any clue why this is happening.

Thank you very much

Expected Behavior

No response

Steps To Reproduce

No response

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

https://stackblitz.com/edit/new-wagmi-xemvdq?file=src/App.tsx

Anything else?

No response

[tmm]

Higher-order functions, like .map, don't carry type semantics very well. The best we can do in this case is by helping out the compiler a bit more asserting const in a few more places so result is now inferred as string | number.

TypeScript Playground

const data: ({
    error: Error;
    result?: undefined;
    status: "failure";
} | {
    error?: undefined;
    result: string | number;
    status: "success";
})[] | undefined

More info microsoft/TypeScript#29841

[Max-3-7]

ah got it, thanks for the info!

[github-actions]

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