brownie.reverts() transaction.py AttributeError on reverted transactions

Environment information

• brownie Version: 1.16.4
• ganache-cli Version: 7.0.2 (@ganache/cli: 0.1.3, @ganache/core: 0.1.3)
• solc Version: 0.8.0
• Python Version: 3.10.2
• OS: win
• platform win32 – Python 3.10.2, pytest-6.2.5, py-1.10.0, pluggy-1.0.0
• plugins: eth-brownie-1.16.4, hypothesis-6.21.6, forked-1.3.0, xdist-1.34.0, web3-5.23.1

Virtual environment

Everything is running in a virtual python venv environment, extended with nodeenv to install ganache. The environment works in all other aspects flawlessly. Setup details can be found here: https://github.com/smartcontractkit/full-blockchain-solidity-course-py/discussions/971 A repository with minimal code reproducing the error is provided here: https://github.com/n4n0b1t3/brownie.reverts.example

What was wrong?

• command ran: brownie test
• Solidity contract code: directory /contracts/ExampleContract.sol

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.6 <0.9.0;

contract ExampleContract {
    address public owner;

    constructor() {
        owner = msg.sender;
    }

    modifier onlyOwner() {
        require(msg.sender == owner, "only owner");
        _;
    }

    function withdraw() public payable onlyOwner {
        payable(msg.sender).transfer(address(this).balance);
    }
}

• the code that caused the failure: directory /test/test_reverts.py

import brownie
from brownie import ExampleContract, accounts, exceptions

def test_only_owner_can_withdraw():
    example_contract = ExampleContract.deploy({"from": accounts[0]})
    bad_account = accounts.add()
    with brownie.reverts():
        example_contract.withdraw({"from": bad_account})

• Variation making use of pytest.raises(): directory /test/test_reverts.py

import brownie
import pytest
from brownie import ExampleContract, accounts, exceptions

def test_only_owner_can_withdraw():
    example_contract = ExampleContract.deploy({"from": accounts[0]})
    bad_account = accounts.add()
    with pytest.raises(exceptions.VirtualMachineError):
        example_contract.withdraw({"from": bad_account})

• full output of the error you received

(.venv) testcode>brownie test
INFORMATION: Es konnten keine Dateien mit dem angegebenen
Muster gefunden werden.
Brownie v1.16.4 - Python development framework for Ethereum

======================================================================================================= test session starts =======================================================================================================
platform win32 -- Python 3.10.2, pytest-6.2.5, py-1.10.0, pluggy-1.0.0
rootdir: C:\Users\Zarathustra\blockchainProjects\testing.revert\testcode
plugins: eth-brownie-1.16.4, hypothesis-6.21.6, forked-1.3.0, xdist-1.34.0, web3-5.23.1
collected 1 item

Launching 'ganache-cli.cmd --accounts 10 --hardfork istanbul --gasLimit 12000000 --mnemonic brownie --port 8545'...

tests\test_reverts.py F                                                                                                                                                                                                      [100%]

============================================================================================================ FAILURES =============================================================================================================
__________________________________________________________________________________________________ test_only_owner_can_withdraw ___________________________________________________________________________________________________

    def test_only_owner_can_withdraw():
        fund_me = ExampleContract.deploy({"from": accounts[0]})
        print(f"FundMe deployed to {fund_me.address}")
        good = accounts[0]
        bad = accounts.add()
        # with pytest.raises(exceptions.VirtualMachineError):
>       with brownie.reverts():

tests\test_reverts.py:12:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
tests\test_reverts.py:13: in test_only_owner_can_withdraw
    fund_me.withdraw({"from": bad})
..\.venv\lib\site-packages\brownie\network\contract.py:1693: in __call__
    return self.transact(*args)
..\.venv\lib\site-packages\brownie\network\contract.py:1566: in transact
    return tx["from"].transfer(
..\.venv\lib\site-packages\brownie\network\account.py:680: in transfer
    receipt._raise_if_reverted(exc)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = <Transaction '0x1f310675db8ad41f0eb4cd9338f35f2800174168b18c019645b5b1d82ade2826'>, exc = None

    def _raise_if_reverted(self, exc: Any) -> None:
        if self.status or CONFIG.mode == "console":
            return
        if not web3.supports_traces:
            # if traces are not available, do not attempt to determine the revert reason
            raise exc or ValueError("Execution reverted")

        if self._dev_revert_msg is None:
            # no revert message and unable to check dev string - have to get trace
            self._expand_trace()
        if self.contract_address:
            source = ""
        elif CONFIG.argv["revert"]:
            source = self._traceback_string()
        else:
            source = self._error_string(1)
            contract = state._find_contract(self.receiver)
            if contract:
                marker = "//" if contract._build["language"] == "Solidity" else "#"
                line = self._traceback_string().split("\n")[-1]
                if marker + " dev: " in line:
                    self._dev_revert_msg = line[line.index(marker) + len(marker) : -5].strip()

>       raise exc._with_attr(
            source=source, revert_msg=self._revert_msg, dev_revert_msg=self._dev_revert_msg
        )
E       AttributeError: 'NoneType' object has no attribute '_with_attr'

..\.venv\lib\site-packages\brownie\network\transaction.py:420: AttributeError
------------------------------------------------------------------------------------------------------ Captured stdout call ------------------------------------------------------------------------------------------------------- 
FundMe deployed to 0x3194cBDC3dbcd3E11a07892e7bA5c3394048Cc87
mnemonic: 'abandon wisdom slot exclude buyer raccoon desert grid inmate flag state castle'
===================================================================================================== short test summary info ===================================================================================================== 
FAILED tests/test_reverts.py::test_only_owner_can_withdraw - AttributeError: 'NoneType' object has no attribute '_with_attr'
======================================================================================================== 1 failed in 6.40s ======================================================================================================== 
Terminating local RPC client...
(.venv) testcode>

How can it be fixed?

I believe this is caused by brownie\network\transaction.py exiting with its own raise exc._with_attr instead of “bubbling up” the error to pytest.raise().

[DJercic]

I just updated brownie to the latest version (1.18.1) and it seems the bug is fixed there

[freddie71010]

@n4n0b1t3 do you think you can close the issue now? Great job with the detailed post.