How do I set a type when passing abi as a param to a function?

[benesjan]

Hello, I am try to create a function which deploys arbitrary contract and I am struggling with setting a type for abi.

How would I do that?

Is there a type for "generic abi thing", "generic event thing" etc.?

[fubhy]

Yes there is. This imho deserves its own section in the docs at some point (how to utilize the type system and adding your own abstraction & functions around it). Best way to learn how to use the generics for this case is to look at the source code of the function(s) you are trying to call. E.g. deployContract in this case: https://github.com/wagmi-dev/viem/blob/43867afa1f1368af3e69a3c6f7a4021a7af0a662/src/actions/wallet/deployContract.ts#L60-L88

What's most relevant here is the generic:

TAbi extends Abi | readonly unknown[]

For bytecode, btw., it's probably sufficient to just type it as Hex (there's also a Viem type for that which is simply an alias for 0x${string}.

[fubhy]

Note that if you want to derive args from the abi you'll have to utilize other generics too (e.g. GetFunctionArgs, etc.)

[benesjan]

Using Narrow<Abi | readonly unknown[]> and Hex solved the issue.

async function deployL1Contract(
  walletClient: WalletClient<HttpTransport, Chain, Account>,
  publicClient: PublicClient<HttpTransport, Chain>,
  abi: Narrow<Abi | readonly unknown[]>,
  bytecode: Hex,
) {
  const hash = await walletClient.deployContract({
    abi,
    bytecode,
  });

  const receipt = await publicClient.waitForTransactionReceipt({ hash });
  const contractAddress = receipt.contractAddress;
  if (!contractAddress) {
    throw new Error(`No contract address found in receipt: ${JSON.stringify(receipt)}`);
  }

  return EthAddress.fromString(receipt.contractAddress!);
}

[tmm]

Worth noting that once we move the minimum TypeScript version to 5.0, you'll be able to drop Narrow<...> for the const type parameter.