hardhat-exposed

A Hardhat plugin to automatically expose internal functions for smart contract testing.

Installation

npm install -D hardhat-exposed

Add to hardhat.config.js:

require('hardhat-exposed');

Note: After setting up for the first time, you may need to recompile with hardhat compile --force once.

Usage

The plugin will create "exposed" versions of your contracts that will be prefixed with an X, and its internal functions will be exposed as external functions with an x prefix.

These exposed contracts will be created in a contracts-exposed directory. We strongly suggest adding this directory to .gitignore.

If you have a contract called Foo, with an internal function called _get:

const Foo = ethers.getContractFactory('XFoo');
// or const Foo = artifacts.require('XFoo');

const foo = Foo.deploy();
await foo.x_get();

The plugin will also generate a constructor to initialize your abstract contracts.

For example, in this set of contracts notice that C is abstract because it doesn't call B's constructor.

contract A {
    constructor(uint a) {}
}
contract B {
    constructor(uint b) {}
}
contract C is A, B {
    constructor(uint c) A(0) {}
}

In the plugin-generated exposed version of C, there will be an additional parameter to initialize B.

contract XC is C {
    constructor(uint256 b, uint256 c) B(b) C(c) {}
}

The order of parameters in this generated constructor will be according to the linearization of the parent contracts, starting with the most base contract and ending with the most derived one. This order can be unintuitive, so in these cases make sure you test the contract was initialized as desired.

Note that if a contract is abstract because it's missing an implementation for a virtual function, the exposed contract will remain abstract too.