Problem testing Brownie FundMe Chainlink demo; Script interacting with contract works on Rinkeby but not Ganache

Question

This is driving me NUTS. I am running through this handy dandy Solidity course

https://www.youtube.com/watch?v=M576WGiDBdQ

Where I am at timestamp 5:45:11, where I write a script to interact with the FundMe contract and it works fine on Rinkeby to call the "getEntranceFee()" function or any function I want to call, but it does not work on ganache-local. I get this error:

Running 'scripts/fund_and_withdraw.py::main'...
  File "<console>", line 1, in <module>
  File "brownie/project/scripts.py", line 69, in run
    return func(*args, **kwargs)
  File "./scripts/fund_and_withdraw.py", line 16, in main
    fund()
  File "./scripts/fund_and_withdraw.py", line 9, in fund
    entrance_fee = fund_me.getEntranceFee()
  File "brownie/network/multicall.py", line 115, in _proxy_call
    result = ContractCall.__call__(*args, **kwargs)  # type: ignore
  File "brownie/network/contract.py", line 1729, in __call__
    return self.call(*args, block_identifier=block_identifier)
  File "brownie/network/contract.py", line 1533, in call
    raise VirtualMachineError(e) from None
VirtualMachineError: revert

I've noticed that I have had issues for some time of having scripts that deploy and run contracts just fine on the testnets. But when I run a script that deploys and interacts with contracts on my local ganache chain, it compiles and deploys soundly but any interaction with it doesn't work. How would I debug this issue? I am at a total loss here. Did I do something wrong in setting up the ganache chain? I thought it was plug and play.

Answer 1

I figured out the answer to this error. Turns out I was deploying using a specific MockV3Aggregator Address and then I had another script to interact with the contract, but used a different MockV3Aggregator address, hence giving me that error. Specifically in my deploy.py function,

    account = get_account()
    # pass the price feed address to our fundme contract's constructor
    # if we are on Rinkeby Network, use said address
    if network.show_active() not in LOCAL_BLOCKCHAIN_ENVIRONMENTS:
        price_feed_address = config["networks"][network.show_active()][
            "eth_usd_price_feed"
        ]
    else:
        deploy_mocks()
        price_feed_address = MockV3Aggregator[-1].address  # gets the latest address

    fund_me = FundMe.deploy(
        "0x8A753747A1Fa494EC906cE90E9f37563A8AF630e", # this should be price_feed_address
        {"from": account},
        publish_source=config["networks"][network.show_active()].get("verify"),
    )
    print(f"Contract deployed to {fund_me.address}")

That address should have been the price_feed_address variable that I didn't use. Whoops.

Thank you all for reading through this thread of me bungle through a straightforward issue.