Handling Custom Error

Question

Why it doesn't work when I use...

$ yarn hardhat --verison 2.10.2

await expect(fundMeConnectedContract.withdraw()
            ).to.be.revertedWith(
                "FundMe__NotOwner"
            )

but this worked

await expect(fundMeConnectedContract.withdraw()
            ).to.be.revertedWithCustomError(
                fundMeConnectedContract,
                "FundMe__NotOwner"
            )

Has the hardhat custom error handling changed since May this year..??

Answer 1

the former is matching against the revert message.

e.g.

.to.be.revertedWith("go away")

would work with this code

require(msg.sender == owner,"go away");

the latter is just matching against the custom error

Answer 2

    await expect(fundMeConnectedContract.withdraw()).to.be.revertedWithCustomError(fundMe, "FundMe__NotOwner")

Hey , buddy if you follow exactly the tutorial. try revertedWithCustomError and add fundMe, "FundMe__NotOwner".

Line explanation :

• fundMe will be your deployed contract
• FundMe__NotOwner the custom error from fundMe.sol

Do also check if you using single or double underscore for FundMe__NotOwner in fundMe.sol

I hope this would help if you still not found out the solution

Answer 3

I hope you got an Answer already, if not just try to delete the custom error passed to revertedWithCustomError and write it down yourself. I copie-pasted it and it could not recognise as defined custom-Error in the contract.