Brownie does not generate proper compilation artifacts for interfaces

Hi,

It looks like the interfaces compilation artifacts generated in build/interfaces are not generated with the same compiler call that build/contracts. So some references ID in the interfaces AST do not match the references from build/contracts.

For example, in the AST generated, the src field is composed of three elements start:length:fileID. When solc generates the compilation artifact fileID will be unique per filename. Because build/interfaces is not generated at the same time that build/contracts, the fileID can collide, breaking integration with third-party tools (such as slither)

For example, if the codebase has two files:

$ cat interfaces/interface.sol 
pragma solidity 0.7.2;

interface I{

}
$ cat contracts/implementation.sol 
pragma solidity 0.7.2;
import "../../interfaces/interface.sol";

contract Imp is I{

}

Running $ solc contracts/implementation.sol --ast-compact-json --allow-paths . will lead the src fields in the AST to be

• x:y:0 for contracts/implementation.sol elements and
• x:y:1 for interfaces/interface.sol elements.

However, running brownie compile will lead all the src to be in the form x:y:0, making it difficult to distinguish if the source maps contracts/implementation.sol or interfaces/interface.sol.

I am not too familiar with how brownie generates build/interfaces, but would it be possible to either:

• Add the compilation artifacts for the interfaces directly into build/contracts (so both in build/contracts for consistency and in build/interfaces for other usages)
• Or have an option to force build/interfaces to be generated with the same call to solc that for build/contracts

This issue is similar to https://github.com/eth-brownie/brownie/issues/772.

[PatrickAlphaC]

@iamdefinitelyahuman can we put out a gitcoin grant perhaps?

[iamdefinitelyahuman]

Sorry just haven’t found the bandwidth to address yet 😬