ParseError: Source file requires different compiler , when using chainlink-brownie-contracts

Question

I'm trying to implement PatrickAlpha NFT implementation Github. When I followed readme instructions, collectibles are minted correctly. But If I tried to change anything in the code , it gives me error like this.

Compiling contracts...
Solc version: 0.6.6
Optimizer: Enabled Runs: 200
EVM Version: Istanbul
CompilerError: solc returned the following errors:
/Users/batuhansesli/.brownie/packages/smartcontractkit/chainlink-brownie-contracts@1.0.2/contracts/src/v0.6/VRFConsumerBase.sol:2:1: ParserError: Source file requires different compiler version (current compiler is 0.6.6+commit.6c089d02.Darwin.appleclang - note that nightly builds are considered to be strictly less than the released version
pragma solidity 0.6.0;
^--------------------^

For debug, I tried to change only ERC721 constructor parameters, but error occured again.

Original Code:

pragma solidity 0.6.6;

import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "@chainlink/contracts/src/v0.6/VRFConsumerBase.sol";

contract AdvancedCollectible is ERC721, VRFConsumerBase {
    uint256 public tokenCounter;
    enum Breed{PUG, SHIBA_INU, ST_BERNARD}
    // add other things
    mapping(bytes32 => address) public requestIdToSender;
    mapping(bytes32 => string) public requestIdToTokenURI;
    mapping(uint256 => Breed) public tokenIdToBreed;
    mapping(bytes32 => uint256) public requestIdToTokenId;
    event requestedCollectible(bytes32 indexed requestId); 


    bytes32 internal keyHash;
    uint256 internal fee;
    
    constructor(address _VRFCoordinator, address _LinkToken, bytes32 _keyhash)
    public 
    VRFConsumerBase(_VRFCoordinator, _LinkToken)
    ERC721("Dogie", "DOG")
    {
        tokenCounter = 0;
        keyHash = _keyhash;
        fee = 0.1 * 10 ** 18;
    }

    function createCollectible(string memory tokenURI, uint256 userProvidedSeed) 
        public returns (bytes32){
            bytes32 requestId = requestRandomness(keyHash, fee, userProvidedSeed);
            requestIdToSender[requestId] = msg.sender;
            requestIdToTokenURI[requestId] = tokenURI;
            emit requestedCollectible(requestId);
    }

    function fulfillRandomness(bytes32 requestId, uint256 randomNumber) internal override {
        address dogOwner = requestIdToSender[requestId];
        string memory tokenURI = requestIdToTokenURI[requestId];
        uint256 newItemId = tokenCounter;
        _safeMint(dogOwner, newItemId);
        _setTokenURI(newItemId, tokenURI);
        Breed breed = Breed(randomNumber % 3); 
        tokenIdToBreed[newItemId] = breed;
        requestIdToTokenId[requestId] = newItemId;
        tokenCounter = tokenCounter + 1;
    }

    function setTokenURI(uint256 tokenId, string memory _tokenURI) public {
        require(
            _isApprovedOrOwner(_msgSender(), tokenId),
            "ERC721: transfer caller is not owner nor approved"
        );
        _setTokenURI(tokenId, _tokenURI);
    }
}

My Code :

pragma solidity 0.6.6;

import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "@chainlink/contracts/src/v0.6/VRFConsumerBase.sol";

contract FootballerCollectible is ERC721, VRFConsumerBase {

    bytes32 internal keyHash;
    uint256 public fee;
    uint256 public tokenCounter;

    enum Player{MBAPPE, NEYMAR, MESSI, RONALDO}

    mapping (bytes32 => address) public requestIdToSender;
    mapping (bytes32 => string) public requestIdToTokenURI;
    mapping (uint256 => Player) public tokenIdToPlayer;
    event requestedCollectible(bytes32 indexed requestId); 


    constructor(address _VRFCoordinator, address _LinkToken, bytes32 _keyhash) public
    VRFConsumer(_VRFCoordinator, _LinkToken)
    ERC721("Footballer", "FTC") 
    {
        keyHash = _keyhash;
        fee = 0.1 * 10 ** 18;
        tokenCounter = 0; 
    }

    function createCollectible(uint256 userProvidedSeed, string memory tokenURI)
    public returns (bytes32) {
        bytes32 requestId = requestRandomness(keyHash, fee, userProvidedSeed);
        requestIdToSender[requestId] = msg.sender;
        requestIdToTokenURI[requestId] = tokenURI;
        emit requestedCollectible(requestId);
    }

    function fulfillRandomness(bytes32 requestId, uint256 randomNumber) internal override{
        address cardOwner = requestIdToSender[requestId];
        string memory tokenURI = requestIdToTokenURI[requestId];
        uint256 newItemId = tokenCounter;
        _safeMint(cardOwner, newItemId);
        _setTokenURI(newItemId, tokenURI);
        Player player = Player(randomNumber % 4);
        tokenIdToPlayer[newItemId] = player;
        requestIdToTokenId[requestId] = newItemId;
        tokenCounter = tokenCounter + 1;


    }
        function setTokenURI(uint256 tokenId, string memory _tokenURI) public {
        require(
            _isApprovedOrOwner(_msgSender(), tokenId),
            "ERC721: transfer caller is not owner nor approved"
        );
        _setTokenURI(tokenId, _tokenURI);
    }
} 

Answer 1

Hi :) In the Error message that you received

Blockquote ParserError: Source file requires different compiler version (current compiler is 0.6.6+commit.6c089d02.Darwin.appleclang - note that nightly builds are considered to be strictly less than the released version pragma solidity 0.6.0;

it says that you are trying to compile your contract with a different version of pragma solidity. The smart contract in question is:

[https://github.com/smartcontractkit/chainlink-brownie-contracts/blob/main/contracts/src/v0.6/VRFConsumerBase.sol]

which is using

pragma solidity ^0.6.0;

You are specifying to use version 0.6.6 in your contract which is later than the selected compiler. To get around this, you can either drop down to ^0.6.0 or you can change your pragma to

    pragma solidity ^0.6.0;

For more information, you can read this ticket