ParserError: Source file requires different compiler version

Question

I tried all that you mentioned in the discussion here (in other questions) and at https://github.com/smartcontractkit/full-blockchain-solidity-course-py/discussions/522 , however it is not solving the issue for me, I also noticed that the current compiler version remains (current compiler is 0.6.12+commit.27d51765.Windows.msvc). But when I right click and select Solidty:Compiler information, it shows 0.8.0.

from output:

Retrieving compiler information:
Compiler using remote version: 'v0.8.0+commit.c7dfd78e', solidity version: 0.8.0+commit.c7dfd78e.Emscripten.clang

Not sure if that is related to the issue I face. Anyways starting with the problem I see when running brownie compile. I get the error below:

error in terminal:

PS D:\Python projects\Solidity dev\demo\smartcontract-lottery> brownie compile
INFO: Could not find files for the given pattern(s).
Brownie v1.17.2 - Python development framework for Ethereum

Compiling contracts...
  Solc version: 0.6.12
  Optimizer: Enabled  Runs: 200
  EVM Version: Istanbul
CompilerError: solc returned the following errors:

C:/Users/rosne/.brownie/packages/OpenZeppelin/openzeppelin-contracts@4.3.0/contracts/access/Ownable.sol:3:1: ParserError: Source file requires different compiler version (current compiler is 0.6.12+commit.27d51765.Windows.msvc) - note that nightly builds are considered to be strictly less than the released version
pragma solidity ^0.8.0;
^---------------------^

C:/Users/rosne/.brownie/packages/smartcontractkit/chainlink-brownie-contracts@0.2.1/contracts/src/v0.8/VRFConsumerBase.sol:2:1: ParserError: Source file requires different compiler version (current compiler is 0.6.12+commit.27d51765.Windows.msvc) - note that nightly builds are considered to be strictly less than the released version
pragma solidity ^0.8.0;
^---------------------^

PS D:\Python projects\Solidity dev\demo\smartcontract-lottery>

My .sol file is Lottery.sol:

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

import "@chainlink/contracts/src/v0.6/interfaces/AggregatorV3Interface.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@chainlink/contracts/src/v0.8/VRFConsumerBase.sol";

contract Lottery is VRFConsumerBase, Ownable {
    uint256 usdEntryFee;
    address payable[] public players;
    address payable public recentWinner;
    uint256 public randomness;
    AggregatorV3Interface internal ethUsdPriceFeed;
    enum LOTTERY_STATE {
        OPEN,
        CLOSED,
        CALCULATING_WINNER
    }

    LOTTERY_STATE public lottery_state;
    uint256 public fee;
    bytes32 public keyhash;

    constructor(
        address _priceFeedAddress,
        address _vrfCoordinator,
        address _link,
        uint256 _fee,
        bytes32 _keyhash
    ) public VRFConsumerBase(_vrfCoordinator, _link) {
        usdEntryFee = 50 * (10**18);
        ethUsdPriceFeed = AggregatorV3Interface(_priceFeedAddress);
        lottery_state = LOTTERY_STATE.CLOSED;
        fee = _fee;
        keyhash = _keyhash;
    }

    function enter() public payable {
        //$50 min
        require(lottery_state == LOTTERY_STATE.OPEN);
        require(msg.value >= getEntranceFee(), "Not enough ETH!");
        players.push(payable(msg.sender));
    }

    function getEntranceFee() public view returns (uint256) {
        (, int256 price, , , ) = ethUsdPriceFeed.latestRoundData();
        uint256 adjustedPrice = uint256(price) * 10**12; //18 decimals
        //$50, 2000 ETH
        //50/2000
        //50*10000/2000
        uint256 costToEnter = (usdEntryFee * 10**18) / adjustedPrice;
        return costToEnter;
    }

    function startLottery() public onlyOwner {
        require(
            lottery_state == LOTTERY_STATE.CLOSED,
            "cant start a new lottery yet"
        );
        lottery_state = LOTTERY_STATE.OPEN;
    }

    function endLottery() public onlyOwner {
        lottery_state = LOTTERY_STATE.CALCULATING_WINNER;
        bytes32 requestId = requestRandomness(keyhash, fee);
    }

    function FulfillRandomness(bytes32 _requestId, uint256 _randomness)
        internal
        override
    {
        require(
            lottery_state == LOTTERY_STATE.CALCULATING_WINNER,
            "you arent there yet!"
        );

        require(_randomness > 0, "random not found");
        uint256 indexOfWinner = _randomness % players.length;
        recentWinner = players[indexOfWinner];
        recentWinner.transfer(address(this).balance);

        //reset

        players = new address payable[](0);
        lottery_state = LOTTERY_STATE.CLOSED;
        randomness = _randomness;
    }
}

I also tried to google some solutions so my settings.json file is a bit different but that didnt help too.

settings.json:

{
    "solidity.compileUsingRemoteVersion": "v0.8.0+commit.c7dfd78e",
    "solidity.defaultCompiler": "remote",
    "solidity.compileUsingLocalVersion": "d:\\Python projects\\Solidity dev\\demo\\smartcontract-lottery\\soljson-v0.8.0+commit.c7dfd78e.js"
    // "solidity.compileUsingRemoteVersion": "v0.7.4+commit.3f05b770",
    // "solidity.enableLocalNodeCompiler": false
}

In the brownie-config.yaml, I tried all the versions of openzepplin contracts too from old to latest (4.4.0, 4.3.0,4.3.2 etc), but same error.

brownie-config.yaml

dependencies:
  - smartcontractkit/chainlink-brownie-contracts@1.1.1
  - OpenZeppelin/openzeppelin-contracts@4.3.0
compiler:
  solc:
    remappings:
      - '@chainlink=smartcontractkit/chainlink-brownie-contracts@0.2.1'
      - '@openzeppelin=OpenZeppelin/openzeppelin-contracts@4.3.0'
networks:
  mainnet-fork:
    eth_usd_price_feed: '0xaEA2808407B7319A31A383B6F8B60f04BCa23cE2'

I also tried to change the compiler in lottery.sol file with

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

Now I get a different error. Completely lost here :(

terminal:

INFO: Could not find files for the given pattern(s).
Brownie v1.17.2 - Python development framework for Ethereum

Compiling contracts...
  Solc version: 0.8.11
  Optimizer: Enabled  Runs: 200
  EVM Version: Istanbul
CompilerError: solc returned the following errors:

ParserError: Source file requires different compiler version (current compiler is 0.8.11+commit.d7f03943.Windows.msvc) - note that nightly builds are considered to be strictly less than the released version
 --> C:/Users/rosne/.brownie/packages/smartcontractkit/chainlink-brownie-contracts@0.2.1/contracts/src/v0.6/interfaces/AggregatorV3Interface.sol:2:1:
  |
2 | pragma solidity ^0.6.0;
  | ^^^^^^^^^^^^^^^^^^^^^^^

PS D:\Python projects\Solidity dev\demo\smartcontract-lottery> 

I am very new to programing in solidity and this is the first course I am following, I don't want to give up so easily, any help is much appreciated.

Answer 1

I had the same issue. For me, it was never resolved by changing the pragma within any .sol file, and it was never solved by changing the global compiler version within "Visual Studio Code". What did solve the issue was manually setting the compiler version within the brownie-config.yaml file. So within the config file there was the below code...

compiler:
 solc:
  version: '0.8.4'

Answer 2

replace with these two statements:

// SPDX-License-Identifier: MIT

pragma solidity >=0.4.22 <0.9.0;

solves the problem

Answer 3

The solution to the error is

// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.9.0;

Use this instead, hope this helps

Answer 4

I managed to find the issue, it was because the function name should be fullfillRandomness instead of FullfillRandomness. So much problem because of a capital F.

function FulfillRandomness(bytes32 _requestId, uint256 _randomness)
        internal
        override

Answer 5

i had the same issue. i had this compiler setting:

pragma solidity >=0.4.22 <0.9.0;

Since we are importing from openzeppelin, I visied github repo and saw that it uses pragma solidity ^0.8.0;

So changed my setting to

 pragma solidity >=0.4.22 <0.8.0;

After compilation I searched for ">=0.6.0 <0.8.0" and got those files. They all from openzeppelin

I did not add solc version to the brownie-yaml file