Lesson 6: error when compiling MockV3Aggregator

[vjumminz]

Hi guys,

I'm getting an error when trying to compile the MockV3Aggregator.sol contract. The error looks like this:

The only thing I did was copy the code from https://github.com/smartcontractkit/chainlink-mix/blob/master/contracts/test/MockV3Aggregator.sol as instructed. Any reason why this might be occurring?

Appreciate the help and really enjoying the course so far :)

[PatrickAlphaC]

Good question!

It looks like you’re trying to have an interface inherit an interface. What if you make this a contract instead of an interface?

[vjumminz]

Appreciate the response -- all it needed was to change solidity versions!

Thank you Patrick for all your effort :)

[romanwiseman]

Hey @vincecummins , could I ask what did you change your solidity version to? And did you have to change on all contracts I presume?

[romanwiseman]

Hey,

I'm having the exact same issue on lesson 6 after copy/pasting the MockV3Aggregator.sol code from the chainlink-mix github.

This contract inherits from AggregatorV2V3Interface.sol which in turn is trying to inherit from AggregatorInterface and AggregatorV3Interace.

// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;

import "./AggregatorInterface.sol";
import "./AggregatorV3Interface.sol";

interface AggregatorV2V3Interface is AggregatorInterface, AggregatorV3Interface
{
}

I tried changing this file to a contract rather than an interface as suggested but it then threw an error saying it needed to be marked as abstract - tried adding a few keyword combinations including abstract and public but to no avail!

I've just checked and all my code is using solidity ^0.6.0 so there doesn't seem to be any conflict there.

Any help would be much appreciated!

(fyi not sure how to comment in here but didn't want to create a duplicate thread... this is obviously not an answer!)

[msperry2014]

Could you make this in a new question with as much information as possible? (what command you ran, what the scripts look like, any contracts)

I found the problem, I copied FundMe.sol from the wrong repository:
Incorrect: https://github.com/PatrickAlphaC/brownie_fund_me/blob/main/contracts/FundMe.sol
Correct: https://github.com/PatrickAlphaC/fund_me/blob/main/FundMe.sol

The difference is in the constructor, the pricefeed parameter must be supplied (I'm assuming later in the lesson).

Thanks for your help Patrick, these lessons are awesome!

[andremiracle]

hey guys i was having same issue and i did clone the repository compiled the smart contracts and all that still nothing happened

[cromewar]

Hello @andremiracle did you change the solidity info? if nothing works please create a new question with more detailed info.

[andremiracle]

The whole issue was from my yaml file which I've fixed. thanks for reaching out

[gigu007]

great it worked for me

[0xZuk0]

I was having the same issue i fixed it by changing solidity version from ^0.6.0 to ^0.7.0. I also tried with ^0.8.0 but it started to give me another error
"TypeError: "send" and "transfer" are only available for objects of type "address payable", not "address""

So i guess just change it to ^0.7.0 and it should work

[PatrickAlphaC]

Version 0.8 of solidity has a few breaking changes. Interesting that moving to 0.7 worked... at first glance... I don't think that should... but if it works that's great!

[engfuentes]

thanks, this solution worked for me.

I changed it to >=0.7.0. and then it downloaded solc 0.8.9 and compiled

solc 0.8.9 successfully installed at: C:\Users\rodri.solcx\solc-v0.8.9\solc.exe
Compiling contracts...
Solc version: 0.8.9
Optimizer: Enabled Runs: 200
EVM Version: Istanbul
Generating build data...

• smartcontractkit/chainlink-brownie-contracts@1.1.1/AggregatorInterface
• smartcontractkit/chainlink-brownie-contracts@1.1.1/AggregatorV2V3Interface
• smartcontractkit/chainlink-brownie-contracts@1.1.1/AggregatorV3Interface
• MockV3Aggregator

[techwithnaga]

Excellent! this solution works for me. When you change solidity version from 0.6.0 to 0.7.0 and compile it, It downloads a new solc version. 0.7.6. For whatever reason, solc 0.7.6 compiles MockV3Aggregator.

[shlok-codes]

Worked for me too.

I changed to ^0.7.0. And it downloaded Solc version: 0.7.6 and compiled.