finished Lesson 7

smart-contract-lottery/brownie-config.yaml

@@ -6,6 +6,7 @@ compiler:
     remappings:
       - "@chainlink=smartcontractkit/[email protected]"
       - "@openzeppelin=OpenZeppelin/[email protected]"
+dotenv: .env
 networks:
   default: development
   development:
@@ -17,6 +18,7 @@ networks:
     link_token: "0x01BE23585060835E02B77ef475b0Cc51aA1e0709"
     keyhash: "0x2ed0feb3e7fd2022120aa84fab1945545a9f2ffc9076fd6156fa96eaff4c1311"
     fee: 1_000_000_000_000_000_00
+    verify: true
   mainnet-fork:
     eth_usd_price_feed: "0x5f4eC3Df9cbd43714FE2740f5E3616155c5b8419"
 wallets:

smart-contract-lottery/contracts/Lottery.sol

@@ -24,6 +24,7 @@ contract Lottery is VRFConsumerBase, Ownable {
     LOTTERY_STATE public lottery_state;
     uint256 public fee;
     bytes32 public keyHash;
+    event RequestedRandomness(bytes32 requestId);
 
 
     constructor(
@@ -33,7 +34,7 @@ contract Lottery is VRFConsumerBase, Ownable {
         uint256 _fee,
         bytes32 _keyHash
     ) public VRFConsumerBase(_vrfCoordinator, _link){
-        usdEntryFee = 50 * (10**28);
+        usdEntryFee = 50 * (10**18);
         ethUsdPriceFeed = AggregatorV3Interface(_priceFeedAddress);
         lottery_state = LOTTERY_STATE.CLOSED;
         fee = _fee;
@@ -72,14 +73,15 @@ contract Lottery is VRFConsumerBase, Ownable {
         // Chainlink VRF offers Verifiable Randomness (provable random number)
         lottery_state = LOTTERY_STATE.CALCULATING_WINNER;
         bytes32 requestId = requestRandomness(keyHash, fee);
+        emit RequestedRandomness(requestId);
     }
 
     function fulfillRandomness(bytes32 _requestId, uint256 _randomness) internal override{
         require(lottery_state == LOTTERY_STATE.CALCULATING_WINNER, "You aren't there yet!");
         require(_randomness > 0, "random-not-found");
         uint256 indexOfWinner = _randomness % players.length;
         recentWinner = players[indexOfWinner];
-        recentWinner.transfer(address(this). balance);
+        recentWinner.transfer(address(this).balance);
         // Reset the lottery
         players = new address payable[](0);
         LOTTERY_STATE.CLOSED;

smart-contract-lottery/interfaces/LinkTokenInterface.sol

@@ -0,0 +1,16 @@
+pragma solidity ^0.6.6;
+
+interface LinkTokenInterface {
+  function allowance(address owner, address spender) external view returns (uint256 remaining);
+  function approve(address spender, uint256 value) external returns (bool success);
+  function balanceOf(address owner) external view returns (uint256 balance);
+  function decimals() external view returns (uint8 decimalPlaces);
+  function decreaseApproval(address spender, uint256 addedValue) external returns (bool success);
+  function increaseApproval(address spender, uint256 subtractedValue) external;
+  function name() external view returns (string memory tokenName);
+  function symbol() external view returns (string memory tokenSymbol);
+  function totalSupply() external view returns (uint256 totalTokensIssued);
+  function transfer(address to, uint256 value) external returns (bool success);
+  function transferAndCall(address to, uint256 value, bytes calldata data) external returns (bool success);
+  function transferFrom(address from, address to, uint256 value) external returns (bool success);
+}

smart-contract-lottery/scripts/deploy_lottery.py

@@ -1,5 +1,6 @@
-from scripts.helpers import get_account, get_contract, config
+from scripts.helpers import get_account, get_contract, config, fund_with_link
 from brownie import Lottery, network, config
+import time
 
 def deploy_lottery():
     account = get_account()
@@ -13,6 +14,39 @@ def deploy_lottery():
         publish_source=config['networks'][network.show_active()].get('verify', False)
     )
     print('Deployed Lottery!')
+    return lottery
+
+def start_lottery():
+    account = get_account()
+    lottery = Lottery[-1]
+    starting_tx = lottery.startLottery({'from':account})
+    starting_tx.wait(1)
+    print('The lottery has started!')
+
+def enter_lottery():
+    account = get_account()
+    lottery = Lottery[-1]
+    value = lottery.getEntranceFee()
+    print(f'Entrance fee is: {value}')
+    tx = lottery.enter({'from': account, 'value': value})
+    tx.wait(1)
+    print('You entered the lottery!')
+
+def end_lottery():
+    account = get_account()
+    lottery = Lottery[-1]
+    # 1) Fund the contract
+    # 2) End the lottery
+    tx = fund_with_link(lottery.address)
+    tx.wait(1)
+
+    ending_transaction = lottery.endLottery({'from': account})
+    ending_transaction.wait(1)
+    time.sleep(120)
+    print(f'{lottery.recentWinner()} is the new winner!')
 
 def main():
-    deploy_lottery()
+    deploy_lottery()
+    start_lottery()
+    enter_lottery()
+    end_lottery()

smart-contract-lottery/scripts/helpers.py

@@ -5,7 +5,8 @@
     Contract,
     MockV3Aggregator,
     VRFCoordinatorMock,
-    LinkToken   
+    LinkToken,
+    interface   
     )
 
 FORKED_LOCAL_ENVIRONMENTS = ['mainnet-fork', 'mainnet-fork-dev']
@@ -67,3 +68,11 @@ def deploy_mocks(decimals=DECIMALS, initial_value=INITIAL_VALUE):
     VRFCoordinatorMock.deploy(link_token.address, {'from': account})
     print('deployed')
 
+def fund_with_link(contract_address, account=None, link_token=None, amount=1_000_000_000_000_000_00):
+    account = account if account else get_account()
+    link_token = link_token if link_token else get_contract('link_token')
+    tx = link_token.transfer(contract_address, amount, {'from': account})
+    tx.wait(1)
+    print('Fund contract')
+    return tx
+

smart-contract-lottery/tests/test_lottery_integration.py

@@ -0,0 +1,19 @@
+from brownie import network 
+import pytest
+from scripts.helpers import LOCAL_BLOCKCHAIN_ENVIRONMENTS, get_account, get_contract, fund_with_link
+import time
+from scripts.deploy_lottery import deploy_lottery
+
+def test_can_pick_winner():
+    if network.show_active() in LOCAL_BLOCKCHAIN_ENVIRONMENTS:
+         pytest.skip()
+    lottery = deploy_lottery()
+    account = get_account()
+    lottery.startLottery({'from': account})
+    lottery.enter({'from':account, 'value': lottery.getEntranceFee()})
+    lottery.enter({'from':account, 'value': lottery.getEntranceFee()})
+    fund_with_link(lottery)
+    lottery.endLottery({'from': account})
+    time.sleep(130)
+    assert lottery.recentWinner() == account
+    assert lottery.balance() == 0

smart-contract-lottery/tests/test_lottery_unit.py

@@ -0,0 +1,67 @@
+from brownie import Lottery,accounts, config, network, exceptions
+from scripts.deploy_lottery import deploy_lottery
+from scripts.helpers import LOCAL_BLOCKCHAIN_ENVIRONMENTS, get_account, fund_with_link, get_contract
+from web3 import Web3
+import pytest
+
+def test_get_entrance_fee():
+    if network.show_active() not in LOCAL_BLOCKCHAIN_ENVIRONMENTS:
+        pytest.skip()
+    # Arrange
+    lottery = deploy_lottery()
+    # Act
+    # 50/4460 = 
+    expected_entrance_fee = Web3.toWei(0.025, 'ether')
+    print(f"exp fee: {Web3.fromWei(expected_entrance_fee, 'ether')}")
+    entrance_fee = lottery.getEntranceFee()
+    print(f"ent fee: {Web3.fromWei(entrance_fee, 'ether')}")
+    #Assert
+    assert expected_entrance_fee == entrance_fee
+
+def test_cant_enter_unless_started():
+    if network.show_active() not in LOCAL_BLOCKCHAIN_ENVIRONMENTS:
+        pytest.skip()
+    lottery = deploy_lottery()
+    with pytest.raises(exceptions.VirtualMachineError):
+        lottery.enter({'from':get_account(), 'value': lottery.getEntranceFee()})
+
+def test_can_start_and_enter_lottery():
+    if network.show_active() not in LOCAL_BLOCKCHAIN_ENVIRONMENTS:
+        pytest.skip()
+    lottery = deploy_lottery()
+    account = get_account()
+    lottery.startLottery({'from': account})
+    lottery.enter({'from':account, 'value': lottery.getEntranceFee()})
+    assert lottery.players(0) == account
+
+def test_can_end_lottery():
+    if network.show_active() not in LOCAL_BLOCKCHAIN_ENVIRONMENTS:
+        pytest.skip()
+    lottery = deploy_lottery()
+    account = get_account()
+    lottery.startLottery({'from': account})
+    lottery.enter({'from': account, 'value': lottery.getEntranceFee()})
+    fund_with_link(lottery)
+    lottery.endLottery({'from': account})
+    assert lottery.lottery_state() == 2
+
+def test_can_pick_winner_correctly():
+    if network.show_active() not in LOCAL_BLOCKCHAIN_ENVIRONMENTS:
+        pytest.skip()
+    lottery = deploy_lottery()
+    account = get_account()
+    lottery.startLottery({'from': account})
+    lottery.enter({'from': account, 'value': lottery.getEntranceFee()})
+    lottery.enter({'from': get_account(index=1), 'value': lottery.getEntranceFee()})
+    lottery.enter({'from': get_account(index = 2), 'value': lottery.getEntranceFee()})
+    fund_with_link(lottery)
+    transaction = lottery.endLottery({'from': account})
+    request_id = transaction.events['RequestedRandomness']['requestId']
+    STATIC_RNG = 777
+    get_contract('vrf_coordinator').callBackWithRandomness(request_id, STATIC_RNG, lottery.address, {'from': account})
+    starting_balance_of_account = account.balance()
+    balance_of_lottery = lottery.balance()
+    # 777 % 3 = 0 - account will be the winner
+    assert lottery.recentWinner() == account
+    assert lottery.balance() == 0
+    assert account.balance() == starting_balance_of_account + balance_of_lottery