Handling Overloaded Functions

[arjun-io]

I'm struggling with using AbiType to handle overloads - it appears that the various input types of are parsed correctly, but the return types are |ed together resulting in improper return types

For example, given an ABI:

[
  'function myFunc(address addr) view returns (uint v)',
  'function myFunc(address a, address b) view returns (address v, uint n)'
]

the resulting typed output for contract.read.myFunc(["0xabc123", "0x123abc"]) would be { v: bigint | Address } - note that n is missing and the type for v is not strict, the expected return type would be { v: Address, u: bigint }

TypeChain would handle this by deduping the function name based on args, so contract.read["myFunc(address,address)"] is correctly separated from contract.read["myFunc(address)"]

I'm not sure if the type extraction system is expressive enough to handle the overload case? My TypeScript expertise is not quite sufficient to be able to understand how to accomplish something like this.

[Raiden1411]

We currently are aware that this is a problem on overloads. Before wagmi v1 the workaround for this was similar. Reference

However with the introduction of viem this no longer applies. The current idea to solve this problem is to narrow the return type based on the provided arguments on those overload functions. So in your example if you just pass the one address as the argument then it would be able to infer the correct return type based on it.

This is currently on the "whiteboard" and should be something that gets solved in the near future.

[Raiden1411]

Example implementation merged in #149

[arjun-io]

Awesome - will further work need to be done in Viem to support this for their contract types or should I be able to simply add a resolution here?

[tmm]

Some work needs to be done to bring this over to viem.

[tmm]

Following up that Viem supports overloads since v2.