Function treated as state variable

[0x19]

Old versions of solidity contracts use for fallback and receive (sometimes even having revert) following function syntax

function () payable { ... }

Current AST parsing will fail if function like above is reached. It will fail under state variable discovery (which is weird).

So far, only investigating potential solutions. Most likely this will be related to grammar file not supporting functions like that. If that's the case, we'll branch off grammar from solidity externals and start maintaining our own (or just apply patches once we sync external repo).

If it's grammar issue, it's in fact, not issue but no longer supported functionality and therefore we cannot file any bugs.
If it's due to antlr-go, then we need to file bug to antlr or fork it off.

It happens very rarely, only with old contracts.

[0x19]

Introduced hack into the #116 to sort this problem out by casting state variable into partial fallback. Problematics with this is that it's a hack, working one to a level as parameters are not parsed properly.

In the future we need to go deep into the antlr4-go and solidity grammar to sort this issue out as our grammar should support not only 0.8 but from the first version to the end.