helper-functions.js

// we can't have these functions in our `helper-hardhat-config`
// since these use the hardhat library
// and it would be a circular dependency
const { run, network } = require("hardhat")
const { networkConfig } = require("./helper-hardhat-config")

const AUTO_FUND = process.env.AUTO_FUND || true

const autoFundCheck = async (contractAddr, networkName, linkTokenAddress, additionalMessage) => {
    const chainId = network.config.chainId
    console.log("Checking to see if contract can be auto-funded with LINK:")
    const amount = networkConfig[chainId]["fundAmount"]
    //check to see if user has enough LINK
    const accounts = await ethers.getSigners()
    const signer = accounts[0]
    const LinkToken = await ethers.getContractFactory("LinkToken")
    const linkTokenContract = new ethers.Contract(linkTokenAddress, LinkToken.interface, signer)
    const balanceBN = await linkTokenContract.balanceOf(signer.address)
    const balance = balanceBN.toString()
    const contractBalanceBN = await linkTokenContract.balanceOf(contractAddr)
    const contractBalance = await contractBalanceBN.toString()
    if (balance > amount && amount > 0 && contractBalance < amount) {
        //user has enough LINK to auto-fund
        //and the contract isn't already funded
        return true
    } else {
        //user doesn't have enough LINK, print a warning
        console.log(
            "Account doesn't have enough LINK to fund contracts, you're deploying to a network where auto funding isn't done by default, the contract is already funded, or you set AUTO_FUND to false."
        )
        console.log(
            `Please obtain LINK via the faucet at https://faucets.chain.link/${networkName} then run the following command to fund contract with LINK:`
        )
        console.log(
            `yarn hardhat fund-link --contract ${contractAddr} --network ${networkName} ${additionalMessage}`
        )
        return false
    }
}

const verify = async (contractAddress, args) => {
    console.log("Verifying contract...")
    try {
        await run("verify:verify", {
            address: contractAddress,
            constructorArguments: args,
        })
    } catch (e) {
        if (e.message.toLowerCase().includes("already verified")) {
            console.log("Already verified!")
        } else {
            console.log(e)
        }
    }
}

// https://github.com/smartcontractkit/chainlink/blob/dbabde12def11a803d995e482e5fc4287d9cfce4/contracts/test/test-helpers/helpers.ts#L93
const stripHexPrefix = (hex) => {
    if (!ethers.utils.isHexString(hex)) {
        throw Error(`Expected valid hex string, got: "${hex}"`)
    }

    return hex.replace("0x", "")
}

// https://github.com/smartcontractkit/chainlink/blob/dbabde12def11a803d995e482e5fc4287d9cfce4/contracts/test/test-helpers/helpers.ts#L21
const addHexPrefix = (hex) => {
    return hex.startsWith("0x") ? hex : `0x${hex}`
}

// https://github.com/smartcontractkit/chainlink/blob/dbabde12def11a803d995e482e5fc4287d9cfce4/contracts/test/test-helpers/helpers.ts#L30
const numToBytes32 = (num) => {
    const hexNum = ethers.utils.hexlify(num)
    const strippedNum = stripHexPrefix(hexNum)
    if (strippedNum.length > 32 * 2) {
        throw Error(
            "Cannot convert number to bytes32 format, value is greater than maximum bytes32 value"
        )
    }
    return addHexPrefix(strippedNum.padStart(32 * 2, "0"))
}

module.exports = {
    autoFundCheck,
    verify,
    numToBytes32,
}