useReadContract infinite type instantiation error

[drake-nathan]

I'm converting from v1 to v2, and swapped a Wagmi cli useReadContract instance. After the fact, TS was throwing this error: "Type instantiation is excessively deep and possibly infinite." I've never seen this error before, any ideas?

[tmm]

Can provide a minimal reproduction? The screenshot isn't helpful.

[armanal]

Error: Type instantiation is excessively deep and possibly infinite

using this example code provided in migration guide should reproduce the issue
Migration Guide

import { useReadContracts } from 'wagmi' 
import { erc20Abi } from 'viem' 

const result = useReadContracts({ 
  allowFailure: false, 
  contracts: [ 
    { 
      address: '0x6B175474E89094C44Da98b954EedeAC495271d0F', 
      abi: erc20Abi, 
      functionName: 'balanceOf', 
      args: ['0x4557B18E779944BFE9d78A672452331C186a9f48'], 
    }, 
    { 
      address: '0x6B175474E89094C44Da98b954EedeAC495271d0F', 
      abi: erc20Abi, 
      functionName: 'decimals', 
    }, 
    { 
      address: '0x6B175474E89094C44Da98b954EedeAC495271d0F', 
      abi: erc20Abi, 
      functionName: 'symbol', 
    }, 
  ] 
}) 

here Typescript gives this error on contracts property:
Type instantiation is excessively deep and possibly infinite

Environment

"@types/node": "20.2.6",
"@types/react": "^18.2.10",
"@types/react-dom": "^18.2.19",
"typescript": "^5.1.3"

[tmm]

Works fine in this TypeScript Playground

[on47sky]

Ensure you have "strictNullChecks: true" in your tsconfig.json. Without this, it doesn't work properly.

[tmm]

FYI strictNullChecks is true by default when strict is true.

[on47sky]

tmm, of course, you're right. However, I've seen projects with strict: true and modifiers that disable some strict rules (especially in migrating legacy projects).

My language isn't perfect. Under "Without this, it doesn't work properly." I meant "If strictNullChecks is false in config"

I mentioned strictNullChecks because it's the only rule from the strict group that lead to this TS error.

The more universal and correct answer is:
Ensure you have strict: true and no standalone rules from the "strict" group in tsconfig.

[valeriivanchev]

@tmm @on47sky I am also getting the same error, my tsconfig is the default vite one. I am generating hooks using the wagmi cli and get the same error. Could you help?

[tmm]

If you think there is bug, feel free to create an issue with a minimal reproduction.