Brownie test IndexError: list index out of range

Question

Macbook Pro : Monterey

Intel Core i7

Brownie v1.17.2

Ganache CLI v6.12.2 (ganache-core: 2.13.2)

I am learning solidity according to reference(https://www.youtube.com/watch?v=M576WGiDBdQ&t=25510s).

I wrote and deployed a smart contract（scripts/deploy.py） using brownie framework, it worked.

Then tried to write a test script（tests/test_simple_storage.py） that gave me error information in the terminal.

Googled this and tried to delete all the files in brownie projects' build folder and deployed the contract（scripts/deploy.py） again， it's the same error.

And tried to change the private key and index, for accounts[0]to account[-1]and account[1]， the same error result.

FYI:I typed the command "ganache-cli —deterministic " in the terminal. So the account and private key are not random.

Saved the Ganache's account[0]'s private key in .env files,like this

.env

export PRIVATE_KEY=0x91114a07f248a1c50951cb11557af5424cc6a49bf61521874c9ae3f4ae239a6d

Error Info：

(base) liwei@liweideMacBook-Pro Brownie_Simple_Storage % brownie test
Brownie v1.17.2 - Python development framework for Ethereum

========================================================== test session starts ===========================================================
platform darwin -- Python 3.8.5, pytest-6.2.5, py-1.11.0, pluggy-1.0.0
rootdir: /Users/liwei/Desktop/demos/practice/Brownie_Simple_Storage
plugins: eth-brownie-1.17.2, xdist-1.34.0, hypothesis-6.27.3, web3-5.25.0, forked-1.3.0
collected 0 items / 1 error                                                                                                              

================================================================= ERRORS =================================================================
_____________________________________________ ERROR collecting tests/test_simple_storage.py ______________________________________________
tests/test_simple_storage.py:5: in <module>
    account = accounts[0]
E   IndexError: list index out of range
======================================================== short test summary info =========================================================
FAILED tests/test_simple_storage.py - IndexError: list index out of range
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Interrupted: 1 error during collection !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
============================================================ 1 error in 0.25s ============================================================
(base) liwei@liweideMacBook-Pro Brownie_Simple_Storage % 

test script--"tests/test_simple_storage.py“

from brownie import accounts, SimpleStorage


# Arrange
account = accounts[0]
print(account)
# Act
simple_storage = SimpleStorage.deploy({"from": account})
starting_value = simple_storage.retrieve()
expected = 0
# Assert
assert starting_value == expected

smartcontract deployed well,use the same local blockchain,ganache-cli “scripts/deploy.py”

from brownie import accounts, config, SimpleStorage
import os


def deploy_simple_storage():

    # load from you set encrypted , not from ganache-cli which is brownie automated connceted to
    # account = accounts.load("MG515-account")
    # print(account)

    # add private key use enviroment variables
    # account = accounts.add(os.getenv("PRIVATE_KEY"))
    # print(account)

    # .deploy() , always need a "from"key in a dictinary when making a transaction
    account = accounts.add(config["wallets"]["from_key"])
    simple_storage = SimpleStorage.deploy({"from": account})
    stored_value = simple_storage.retrieve()
    print("Current stored value is ：")
    print(stored_value)
    print("Updating Contract...")
    transaction = simple_storage.store(15, {"from": account})
    transaction.wait(1)
    updated_store_value = simple_storage.retrieve()
    print("Current stored value is ：")
    print(updated_store_value)
    print(account)


def main():
    deploy_simple_storage()

updated on 20220111

After read brownie docs find this command "network.connect("development")" ,is this command set the network right , I remembered brownie should default connect to development network.

so updated the code like this

from brownie import accounts, SimpleStorage, network


network.connect("development")

# Arrange
account = accounts[0]

print(accounts)
# Act
simple_storage = SimpleStorage.deploy({"from": account})
starting_value = simple_storage.retrieve()
expected = 0
# Assert

assert starting_value == expected

and the terminal give one warning information

(base) liwei@liweideMacBook-Pro Brownie_Simple_Storage % brownie test
Brownie v1.17.2 - Python development framework for Ethereum

========================================================== test session starts ==========================================================
platform darwin -- Python 3.8.5, pytest-6.2.5, py-1.11.0, pluggy-1.0.0
rootdir: /Users/liwei/Desktop/demos/practice/Brownie_Simple_Storage
plugins: eth-brownie-1.17.2, xdist-1.34.0, hypothesis-6.27.3, web3-5.25.0, forked-1.3.0
collected 0 items                                                                                                                       

=========================================================== warnings summary ============================================================
../../../../.local/pipx/venvs/eth-brownie/lib/python3.8/site-packages/brownie/network/main.py:44
  /Users/liwei/.local/pipx/venvs/eth-brownie/lib/python3.8/site-packages/brownie/network/main.py:44: BrownieEnvironmentWarning: Development network has a block height of 2
    warnings.warn(

-- Docs: https://docs.pytest.org/en/stable/warnings.html
========================================================== 1 warning in 0.49s ===========================================================

Answer 1

When connecting to a remote network via a hosted node such as Infura, the Accounts container will be empty. Before you can perform any transactions you must add a local account to Brownie. Looks like you are not on development environment.

Brownie documentation will guide you how to set up accounts