Contract cannot parse a transaction invocation with anonymous function call

[jondoe1337]

Edit The input parameter of the function org.ethereum.core.CallTransaction.Contract.parseInvocation(byte[]) is checked for a minimum length of 4 (still couldn't figure out why 4).

However if we take this transaction as an example: https://etherscan.io/tx/0xcbbda47e74d692987bcfea5bbd63c4c5ca2b8da9d8c55c19a53c9256343bf4af And the contract: https://etherscan.io/address/0xf069d9f8e394f23878e6beccbdef41c4a957b662#code If I'm correct then the anonymous function in line 190 of the contract was executed in this transaction - which requires no params/names.

But that would also require to let the function getBySignatureHash find the anonymous function.

[mkalinin]

still couldn't figure out why 4

This is how function signature is encoded in tx.data: hash(methodName)[:4]. This is a default fallback function which is triggered when contract address receives value > 0. And, basically, there is no reason to parse this invocation (in terms of Contract.parseInvocation(byte[])) cause data array is always empty for such calls. It may be worth to add a default function as a result of Contract.parseInvocation(byte[]) with empty data array.

[jondoe1337]

Okay I see the point not to parse the invocation in that case. Therefore I worked around like this:

if (input.isEmpty())
{
      Function fallbackFunction = Arrays.stream(c.functions).filter(f -> "".equals(f.name) && f.type == FunctionType.fallback).findFirst()
                                              .orElse(null);
      if (fallbackFunction != null)
      {
          invocation = new Invocation(c, fallbackFunction, new Object[0]);
      }
}

It may be worth to add a default function as a result of Contract.parseInvocation(byte[]) with empty data array.

Agree to that, but might have a low priority.