feat: add mock oracle (#11)

Signed-off-by: Pablo Maldonado <pablo@umaproject.org>

.gitmodules

@@ -7,3 +7,6 @@
 [submodule "lib/oval-quickstart"]
 	path = lib/oval-quickstart
 	url = https://github.com/UMAprotocol/oval-quickstart
+[submodule "lib/oval-contracts"]
+	path = lib/oval-contracts
+	url = https://github.com/UMAprotocol/oval-contracts

remappings.txt

@@ -1,4 +1,5 @@
 ds-test/=lib/forge-std/lib/ds-test/src/
 forge-std/=lib/forge-std/src/
 oval-quickstart/=lib/oval-quickstart/src/
+oval-contracts/=lib/oval-contracts/src/
 @openzeppelin/contracts/=lib/openzeppelin-contracts/contracts/

script/HoneyPot.s.sol

@@ -8,10 +8,12 @@ import {HoneyPot} from "../src/HoneyPot.sol";
 import {HoneyPotDAO} from "../src/HoneyPotDAO.sol";
 import {ChainlinkOvalImmutable, IAggregatorV3Source} from "oval-quickstart/ChainlinkOvalImmutable.sol";
 
+import {MockV3Aggregator} from "../src/mock/MockV3Aggregator.sol";
+
 contract HoneyPotDeploymentScript is Script {
     function run() external {
         uint256 deployerPrivateKey = vm.envUint("PRIVATE_KEY");
-        address chainlink = vm.envAddress("SOURCE_ADDRESS");
+        address chainlink = vm.envOr("SOURCE_ADDRESS", address(0));
         uint256 lockWindow = vm.envUint("LOCK_WINDOW");
         uint256 maxTraversal = vm.envUint("MAX_TRAVERSAL");
         address unlocker = vm.envAddress("UNLOCKER");
@@ -24,9 +26,18 @@ contract HoneyPotDeploymentScript is Script {
         console.log("  - Max traversal: ", maxTraversal);
         console.log("  - Unlocker: ", unlockers[0]);
 
+        vm.startBroadcast(deployerPrivateKey);
+
+        if(chainlink == address(0)) {
+            console.log("Chainlink source address is not set");
+            console.log("Deploying a mock Chainlink source");
+            MockV3Aggregator mock = new MockV3Aggregator(8, 100000000000);
+            chainlink = address(mock);
+            console.log("Deployed mock Chainlink source at address: ", chainlink);
+        }
+
         IAggregatorV3Source source = IAggregatorV3Source(chainlink);
         uint8 decimals = IAggregatorV3Source(chainlink).decimals();
-        vm.startBroadcast(deployerPrivateKey);
 
         ChainlinkOvalImmutable oracle =
             new ChainlinkOvalImmutable(source, decimals, lockWindow, maxTraversal, unlockers);

src/HoneyPot.sol

@@ -15,9 +15,9 @@ contract HoneyPot is Ownable {
     IAggregatorV3Source public oracle; // Oval serving as a Chainlink oracle
 
     event OracleUpdated(address indexed newOracle);
-    event HoneyPotCreated(address indexed creator, int256 liquidationPrice, uint256 initialBalance);
-    event HoneyPotEmptied(address indexed honeyPotCreator, address indexed trigger, uint256 amount);
-    event PotReset(address indexed owner, uint256 amount);
+    event HoneyPotCreated(address indexed owner, int256 initialPrice, uint256 amount);
+    event HoneyPotEmptied(address indexed owner, address indexed liquidator, uint256 amount);
+    event HoneyPotReset(address indexed owner, uint256 amount);
 
     constructor(IAggregatorV3Source _oracle) {
         oracle = _oracle;
@@ -40,30 +40,30 @@ contract HoneyPot is Ownable {
         emit HoneyPotCreated(msg.sender, currentPrice, msg.value);
     }
 
-    function _emptyPotForUser(address honeyPotCreator, address recipient) internal returns (uint256 amount) {
-        HoneyPotDetails storage userPot = honeyPots[honeyPotCreator];
+    function _emptyPotForUser(address owner, address recipient) internal returns (uint256 amount) {
+        HoneyPotDetails storage userPot = honeyPots[owner];
 
         amount = userPot.balance;
         userPot.balance = 0; // reset the balance
         userPot.liquidationPrice = 0; // reset the liquidation price
         Address.sendValue(payable(recipient), amount);
     }
 
-    function emptyHoneyPot(address honeyPotCreator) external {
+    function emptyHoneyPot(address owner) external {
         (, int256 currentPrice,,,) = oracle.latestRoundData();
         require(currentPrice >= 0, "Invalid price from oracle");
 
-        HoneyPotDetails storage userPot = honeyPots[honeyPotCreator];
+        HoneyPotDetails storage userPot = honeyPots[owner];
 
         require(currentPrice != userPot.liquidationPrice, "Liquidation price reached for this user");
         require(userPot.balance > 0, "No balance to withdraw");
 
-        uint256 withdrawnAmount = _emptyPotForUser(honeyPotCreator, msg.sender);
-        emit HoneyPotEmptied(honeyPotCreator, msg.sender, withdrawnAmount);
+        uint256 withdrawnAmount = _emptyPotForUser(owner, msg.sender);
+        emit HoneyPotEmptied(owner, msg.sender, withdrawnAmount);
     }
 
     function resetPot() external {
         uint256 withdrawnAmount = _emptyPotForUser(msg.sender, msg.sender);
-        emit PotReset(msg.sender, withdrawnAmount);
+        emit HoneyPotReset(msg.sender, withdrawnAmount);
     }
 }

src/mock/MockV3Aggregator.sol

@@ -0,0 +1,83 @@
+pragma solidity ^0.8.0;
+
+import {IAggregatorV3} from "oval-contracts/interfaces/chainlink/IAggregatorV3.sol";
+
+contract MockV3Aggregator is IAggregatorV3 {
+
+  event AnswerUpdated(int256 indexed current, uint256 indexed roundId, uint256 updatedAt);
+
+  address public immutable aggregator;
+  uint256 public constant version = 0;
+
+  uint8 public override decimals;
+  int256 public override latestAnswer;
+  uint256 public override latestTimestamp;
+  uint256 public latestRound;
+
+  mapping(uint256 => int256) public getAnswer;
+  mapping(uint256 => uint256) public getTimestamp;
+  mapping(uint256 => uint256) private getStartedAt;
+
+  constructor(uint8 _decimals, int256 _initialAnswer) {
+    decimals = _decimals;
+    updateAnswer(_initialAnswer);
+    aggregator = address(this); // For simplicity, we set the aggregator address to the contract address
+  }
+
+  function updateAnswer(int256 _answer) internal {
+    latestAnswer = _answer;
+    latestTimestamp = block.timestamp;
+    latestRound++;
+    getAnswer[latestRound] = _answer;
+    getTimestamp[latestRound] = block.timestamp;
+    getStartedAt[latestRound] = block.timestamp;
+
+    emit AnswerUpdated(_answer, latestRound, block.timestamp);
+  }
+
+  // This function is part of the AccessControlledOffchainAggregator interface. It is used to
+  // update the new price and look like a transmit function from a real Chainlink Aggregator
+  function transmit(
+    bytes calldata _report, // _report should be the ABI encoded int256 new answer
+    bytes32[] calldata _rs, bytes32[] calldata _ss, bytes32 _rawVs
+  )
+    external
+  {
+    int256 newAnswer = abi.decode(_report, (int256));
+    updateAnswer(newAnswer);
+  }
+
+  function updateRoundData(uint80 _roundId, int256 _answer, uint256 _timestamp, uint256 _startedAt) public {
+    latestRound = _roundId;
+    latestAnswer = _answer;
+    latestTimestamp = _timestamp;
+    getAnswer[latestRound] = _answer;
+    getTimestamp[latestRound] = _timestamp;
+    getStartedAt[latestRound] = _startedAt;
+  }
+
+  function getRoundData(
+    uint80 _roundId
+  )
+    external
+    view
+    returns (uint80 roundId, int256 answer, uint256 startedAt, uint256 updatedAt, uint80 answeredInRound)
+  {
+    return (_roundId, getAnswer[_roundId], getStartedAt[_roundId], getTimestamp[_roundId], _roundId);
+  }
+
+  function latestRoundData()
+    external
+    view
+    override
+    returns (uint80 roundId, int256 answer, uint256 startedAt, uint256 updatedAt, uint80 answeredInRound)
+  {
+    return (
+      uint80(latestRound),
+      getAnswer[latestRound],
+      getStartedAt[latestRound],
+      getTimestamp[latestRound],
+      uint80(latestRound)
+    );
+  }
+}

test/HoneyPot.sol

@@ -6,13 +6,15 @@ import {HoneyPot} from "../src/HoneyPot.sol";
 import {HoneyPotDAO} from "../src/HoneyPotDAO.sol";
 import {ChainlinkOvalImmutable, IAggregatorV3Source} from "oval-quickstart/ChainlinkOvalImmutable.sol";
 
+import {MockV3Aggregator} from "../src/mock/MockV3Aggregator.sol";
+
 contract HoneyPotTest is CommonTest {
     event ReceivedEther(address sender, uint256 amount);
     event DrainedEther(address to, uint256 amount);
     event OracleUpdated(address indexed newOracle);
-    event HoneyPotCreated(address indexed creator, int256 liquidationPrice, uint256 initialBalance);
-    event HoneyPotEmptied(address indexed honeyPotCreator, address indexed trigger, uint256 amount);
-    event PotReset(address indexed owner, uint256 amount);
+    event HoneyPotCreated(address indexed owner, int256 initialPrice, uint256 initialBalance);
+    event HoneyPotEmptied(address indexed owner, address indexed liquidator, uint256 amount);
+    event HoneyPotReset(address indexed owner, uint256 amount);
 
     IAggregatorV3Source chainlink = IAggregatorV3Source(0x5f4eC3Df9cbd43714FE2740f5E3616155c5b8419);
     ChainlinkOvalImmutable oracle;
@@ -63,7 +65,7 @@ contract HoneyPotTest is CommonTest {
 
         // Reset HoneyPot for the caller
         vm.expectEmit(true, true, true, true);
-        emit PotReset(address(this), honeyPotBalance);
+        emit HoneyPotReset(address(this), honeyPotBalance);
         honeyPot.resetPot();
         (, uint256 testhoneyPotBalanceReset) = honeyPot.honeyPots(address(this));
         assertTrue(testhoneyPotBalanceReset == 0);
@@ -106,6 +108,42 @@ contract HoneyPotTest is CommonTest {
         assertTrue(testhoneyPotBalanceTwo == honeyPotBalance);
     }
 
+    function testCrackHoneyPotWithMockOracle() public {
+        // Setup mock oracle
+        MockV3Aggregator mock = new MockV3Aggregator(8, 100000000000);
+        address[] memory unlockers = new address[](1);
+        unlockers[0] = address(this);
+        oracle = new ChainlinkOvalImmutable(IAggregatorV3Source(address(mock)), 8, 3, 10, unlockers);
+        honeyPot = new HoneyPot(IAggregatorV3Source(address(oracle)));
+
+        // Create HoneyPot for the caller
+        (, int256 currentPrice,,,) = oracle.latestRoundData();
+        vm.expectEmit(true, true, true, true);
+        emit HoneyPotCreated(address(this), currentPrice, honeyPotBalance);
+        honeyPot.createHoneyPot{value: honeyPotBalance}();
+        (, uint256 testhoneyPotBalance) = honeyPot.honeyPots(address(this));
+        assertTrue(testhoneyPotBalance == honeyPotBalance);
+
+        // Simulate price change
+        int256 newAnswer = (currentPrice * 103) / 100;
+        bytes32[] memory empty = new bytes32[](0);
+        mock.transmit(abi.encode(newAnswer), empty, empty, bytes32(0));
+
+        // Unlock the latest value
+        oracle.unlockLatestValue();
+
+        uint256 liquidatorBalanceBefore = liquidator.balance;
+
+        vm.prank(liquidator);
+        vm.expectEmit(true, true, true, true);
+        emit HoneyPotEmptied(address(this), liquidator, honeyPotBalance);
+        honeyPot.emptyHoneyPot(address(this));
+
+        uint256 liquidatorBalanceAfter = liquidator.balance;
+
+        assertTrue(liquidatorBalanceAfter == liquidatorBalanceBefore + honeyPotBalance);
+    }
+
     function testHoneyPotDAO() public {
         vm.expectEmit(true, true, true, true);
         emit ReceivedEther(address(this), 1 ether);