Added flashloans to e2e tests (#386)

* Added flashloans to e2e tests

* Removed error from mock contract

* fix: patch collector

* Removed duplicated deployments of the MockFlashLoanReceiver contract

* Fixed tests CapsPlusRiskSteward (updated fork block)

* Patched deal2 function for the sUSD token in the OPTIMISM network

---------

Co-authored-by: Lukas <lukasstrassel@googlemail.com>

scripts/FreezingStewards.s.sol

@@ -6,7 +6,6 @@ import {FreezingSteward} from '../src/riskstewards/FreezingSteward.sol';
 import {AaveV3BNB} from 'aave-address-book/AaveV3BNB.sol';
 import {AaveV3Gnosis} from 'aave-address-book/AaveV3Gnosis.sol';
 import {AaveV3Scroll} from 'aave-address-book/AaveV3Scroll.sol';
-import {AaveV3PolygonZkEvm} from 'aave-address-book/AaveV3PolygonZkEvm.sol';
 
 contract DeployGno is GnosisScript {
   function run() external broadcast {
@@ -25,9 +24,3 @@ contract DeployScroll is ScrollScript {
     new FreezingSteward(AaveV3Scroll.ACL_MANAGER, AaveV3Scroll.POOL_CONFIGURATOR);
   }
 }
-
-contract DeployZkEvm is PolygonZkEvmScript {
-  function run() external broadcast {
-    new FreezingSteward(AaveV3PolygonZkEvm.ACL_MANAGER, AaveV3PolygonZkEvm.POOL_CONFIGURATOR);
-  }
-}

scripts/RiskStewards.s.sol

@@ -15,7 +15,6 @@ import {AaveV3Gnosis} from 'aave-address-book/AaveV3Gnosis.sol';
 import {IPoolAddressesProvider, IPool, IPoolConfigurator, IAaveOracle, IPoolDataProvider, IACLManager} from 'aave-address-book//AaveV3.sol';
 import {AaveV3BNB} from 'aave-address-book/AaveV3BNB.sol';
 import {AaveV3Scroll} from 'aave-address-book/AaveV3Scroll.sol';
-import {AaveV3PolygonZkEvm} from 'aave-address-book/AaveV3PolygonZkEvm.sol';
 import {AaveV3EthereumLido} from 'aave-address-book/AaveV3EthereumLido.sol';
 import {AaveV3EthereumEtherFi} from 'aave-address-book/AaveV3EthereumEtherFi.sol';
 
@@ -129,17 +128,6 @@ contract DeployScroll is ScrollScript {
   }
 }
 
-contract DeployZkEvm is PolygonZkEvmScript {
-  function run() external broadcast {
-    new CapsPlusRiskSteward(
-      AaveV3PolygonZkEvm.AAVE_PROTOCOL_DATA_PROVIDER,
-      IAaveV3ConfigEngine(AaveV3PolygonZkEvm.CONFIG_ENGINE),
-      0xC165b4ae0dfB650E0123d4A70D260029Cb6e2C0f,
-      5 days
-    );
-  }
-}
-
 contract DeployLidoEthereum is EthereumScript {
   function run() external broadcast {
     new CapsPlusRiskSteward(

src/CollectorUtils.sol

@@ -1,8 +1,7 @@
 // SPDX-License-Identifier: MIT
 pragma solidity ^0.8.0;
 
-import {IPool, DataTypes} from 'aave-address-book/AaveV3.sol';
-import {ICollector} from 'aave-address-book/common/ICollector.sol';
+import {IPool, DataTypes, ICollector} from 'aave-address-book/AaveV3.sol';
 import {ILendingPool, DataTypes as V2DataTypes} from 'aave-address-book/AaveV2.sol';
 import {IERC20} from 'openzeppelin-contracts/contracts/token/ERC20/IERC20.sol';
 import {SafeERC20} from 'openzeppelin-contracts/contracts/token/ERC20/utils/SafeERC20.sol';
@@ -80,7 +79,7 @@ library CollectorUtils {
     if (input.amount == type(uint256).max) {
       input.amount = IERC20(input.underlying).balanceOf(address(collector));
     }
-    collector.transfer(input.underlying, address(this), input.amount);
+    collector.transfer(IERC20(input.underlying), address(this), input.amount);
     IERC20(input.underlying).forceApprove(input.pool, input.amount);
     IPool(input.pool).supply(input.underlying, input.amount, address(collector), 0);
   }
@@ -163,7 +162,7 @@ library CollectorUtils {
       input.amount = IERC20(input.fromUnderlying).balanceOf(address(collector));
     }
 
-    collector.transfer(input.fromUnderlying, swapper, input.amount);
+    collector.transfer(IERC20(input.fromUnderlying), swapper, input.amount);
     uint256 swapperBalance = IERC20(input.fromUnderlying).balanceOf(swapper);
 
     // some tokens, like stETH, can loose 1-2wei on transfer
@@ -204,7 +203,7 @@ library CollectorUtils {
       revert InvalidZeroAmount();
     }
 
-    collector.transfer(aTokenAddress, address(this), input.amount);
+    collector.transfer(IERC20(aTokenAddress), address(this), input.amount);
 
     // in case of imprecision during the aTokenTransfer withdraw a bit less
     uint256 balanceAfterTransfer = IERC20(aTokenAddress).balanceOf(address(this));

src/CommonTestBase.sol

@@ -90,7 +90,13 @@ contract CommonTestBase is Test {
     if (block.chainid == ChainIds.OPTIMISM) {
       // sUSD
       if (asset == AaveV3OptimismAssets.sUSD_UNDERLYING) {
-        vm.prank(AaveV3OptimismAssets.sUSD_A_TOKEN);
+        deal(
+          0x92bAc115d89cA17fd02Ed9357CEcA32842ACB4c2,
+          0xf2107A85d8b79CBd2c5b2Bb63CA73Fd068040b67,
+          amount
+        );
+
+        vm.prank(0xf2107A85d8b79CBd2c5b2Bb63CA73Fd068040b67);
         IERC20(asset).transfer(user, amount);
         return true;
       }

src/ProtocolV3TestBase.sol

@@ -7,6 +7,7 @@ import {IERC20} from 'openzeppelin-contracts/contracts/token/ERC20/IERC20.sol';
 import {IERC20Metadata} from 'openzeppelin-contracts/contracts/token/ERC20/extensions/IERC20Metadata.sol';
 import {SafeERC20} from 'openzeppelin-contracts/contracts/token/ERC20/utils/SafeERC20.sol';
 import {ReserveConfiguration} from 'aave-v3-origin/contracts/protocol/libraries/configuration/ReserveConfiguration.sol';
+import {PercentageMath} from 'aave-v3-origin/contracts/protocol/libraries/math/PercentageMath.sol';
 import {IDefaultInterestRateStrategyV2} from 'aave-v3-origin/contracts/interfaces/IDefaultInterestRateStrategyV2.sol';
 import {AaveV3EthereumAssets} from 'aave-address-book/AaveV3Ethereum.sol';
 import {DiffUtils} from 'aave-v3-origin-tests/utils/DiffUtils.sol';
@@ -16,6 +17,7 @@ import {IInitializableAdminUpgradeabilityProxy} from './interfaces/IInitializabl
 import {ExtendedAggregatorV2V3Interface} from './interfaces/ExtendedAggregatorV2V3Interface.sol';
 import {CommonTestBase, ReserveTokens} from './CommonTestBase.sol';
 import {ILegacyDefaultInterestRateStrategy} from './dependencies/ILegacyDefaultInterestRateStrategy.sol';
+import {MockFlashLoanReceiver} from './mocks/MockFlashLoanReceiver.sol';
 
 struct LocalVars {
   IPoolDataProvider.TokenData[] reserves;
@@ -39,8 +41,11 @@ struct InterestStrategyValues {
  */
 contract ProtocolV3TestBase is RawProtocolV3TestBase, CommonTestBase {
   using ReserveConfiguration for DataTypes.ReserveConfigurationMap;
+  using PercentageMath for uint256;
   using SafeERC20 for IERC20;
 
+  MockFlashLoanReceiver internal flashLoanReceiver;
+
   /**
    * @dev runs the default test suite that should run on any proposal touching the aave protocol which includes:
    * - diffing the config
@@ -127,6 +132,10 @@ contract ProtocolV3TestBase is RawProtocolV3TestBase, CommonTestBase {
    * @param pool the pool that should be tested
    */
   function e2eTest(IPool pool) public {
+    if (address(flashLoanReceiver) == address(0)) {
+      flashLoanReceiver = new MockFlashLoanReceiver();
+    }
+
     ReserveConfig[] memory configs = _getReservesConfigs(pool);
     ReserveConfig memory collateralConfig = _getGoodCollateral(configs);
     uint256 snapshot = vm.snapshotState();
@@ -304,6 +313,33 @@ contract ProtocolV3TestBase is RawProtocolV3TestBase, CommonTestBase {
 
       vm.revertToState(snapshotAfterDeposits);
     }
+
+    // test flashloans
+    if (testAssetConfig.isFlashloanable) {
+      if (address(flashLoanReceiver) == address(0)) {
+        flashLoanReceiver = new MockFlashLoanReceiver();
+      }
+
+      _flashLoan({
+        config: testAssetConfig,
+        pool: pool,
+        user: collateralSupplier,
+        receiverAddress: address(flashLoanReceiver),
+        amount: testAssetAmount,
+        interestRateMode: 0
+      });
+
+      if (testAssetConfig.borrowingEnabled) {
+        _flashLoan({
+          config: testAssetConfig,
+          pool: pool,
+          user: collateralSupplier,
+          receiverAddress: address(flashLoanReceiver),
+          amount: testAssetAmount,
+          interestRateMode: 2
+        });
+      }
+    }
   }
 
   /**
@@ -518,6 +554,76 @@ contract ProtocolV3TestBase is RawProtocolV3TestBase, CommonTestBase {
     vm.stopPrank();
   }
 
+  function _flashLoan(
+    ReserveConfig memory config,
+    IPool pool,
+    address user,
+    address receiverAddress,
+    uint256 amount,
+    uint256 interestRateMode
+  ) internal {
+    vm.startPrank(user);
+
+    uint256 underlyingTokenBalanceOfATokenBefore = IERC20(config.underlying).balanceOf(
+      config.aToken
+    );
+    uint256 debtTokenBalanceOfUserBefore = IERC20(config.variableDebtToken).balanceOf(user);
+
+    uint256 totalPremium;
+    if (interestRateMode == 0) {
+      uint256 flashLoanPremiumTotal = pool.FLASHLOAN_PREMIUM_TOTAL();
+
+      totalPremium = amount.percentMul(flashLoanPremiumTotal);
+
+      deal2(config.underlying, receiverAddress, totalPremium);
+    }
+
+    console.log('FLASH LOAN: %s, Amount: %s', config.symbol, amount);
+
+    {
+      address[] memory assets = new address[](1);
+      assets[0] = config.underlying;
+
+      uint256[] memory amounts = new uint256[](1);
+      amounts[0] = amount;
+
+      uint256[] memory interestRateModes = new uint256[](1);
+      interestRateModes[0] = interestRateMode;
+
+      pool.flashLoan({
+        receiverAddress: receiverAddress,
+        assets: assets,
+        amounts: amounts,
+        interestRateModes: interestRateModes,
+        onBehalfOf: user,
+        params: '0x',
+        referralCode: 0
+      });
+    }
+
+    uint256 underlyingTokenBalanceOfATokenAfter = IERC20(config.underlying).balanceOf(
+      config.aToken
+    );
+    uint256 debtTokenBalanceOfUserAfter = IERC20(config.variableDebtToken).balanceOf(user);
+
+    if (interestRateMode == 0) {
+      assertEq(
+        underlyingTokenBalanceOfATokenBefore + totalPremium,
+        underlyingTokenBalanceOfATokenAfter
+      );
+
+      assertEq(debtTokenBalanceOfUserAfter, debtTokenBalanceOfUserBefore);
+    } else {
+      assertGt(underlyingTokenBalanceOfATokenBefore, underlyingTokenBalanceOfATokenAfter);
+      assertEq(underlyingTokenBalanceOfATokenBefore - amount, underlyingTokenBalanceOfATokenAfter);
+
+      assertGt(debtTokenBalanceOfUserAfter, debtTokenBalanceOfUserBefore);
+      assertApproxEqAbs(debtTokenBalanceOfUserAfter, debtTokenBalanceOfUserBefore + amount, 1);
+    }
+
+    vm.stopPrank();
+  }
+
   function getIsVirtualAccActive(
     DataTypes.ReserveConfigurationMap memory configuration
   ) external pure returns (bool) {

src/mocks/MockFlashLoanReceiver.sol

@@ -0,0 +1,23 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.10;
+
+import {IERC20} from 'openzeppelin-contracts/contracts/token/ERC20/IERC20.sol';
+import {SafeERC20} from 'openzeppelin-contracts/contracts/token/ERC20/utils/SafeERC20.sol';
+
+contract MockFlashLoanReceiver {
+  using SafeERC20 for IERC20;
+
+  function executeOperation(
+    address[] calldata assets,
+    uint256[] calldata amounts,
+    uint256[] calldata premiums,
+    address /* initiator */,
+    bytes calldata /* params */
+  ) external returns (bool) {
+    for (uint256 i = 0; i < assets.length; i++) {
+      IERC20(assets[i]).forceApprove(msg.sender, amounts[i] + premiums[i]);
+    }
+
+    return true;
+  }
+}

tests/CollectorUtils.t.sol

@@ -3,6 +3,7 @@ pragma solidity ^0.8.0;
 
 import 'forge-std/Test.sol';
 
+import {IAccessControl} from 'openzeppelin-contracts/contracts/access/IAccessControl.sol';
 import {AaveV3Ethereum, AaveV3EthereumAssets, ICollector, IPool} from 'aave-address-book/AaveV3Ethereum.sol';
 import {AaveV2Ethereum, AaveV2EthereumAssets, ILendingPool} from 'aave-address-book/AaveV2Ethereum.sol';
 import {MiscEthereum} from 'aave-address-book/MiscEthereum.sol';
@@ -24,10 +25,10 @@ contract CollectorUtilsTest is Test {
   address testReceiver = address(0xB0B);
 
   function setUp() public {
-    vm.createSelectFork(vm.rpcUrl('mainnet'), 20420006);
+    vm.createSelectFork(vm.rpcUrl('mainnet'), 21922962);
 
-    vm.prank(COLLECTOR.getFundsAdmin());
-    COLLECTOR.setFundsAdmin(address(this));
+    vm.prank(AaveV3Ethereum.ACL_ADMIN);
+    IAccessControl(address(COLLECTOR)).grantRole('FUNDS_ADMIN', address(this));
   }
 
   function testDepositCollectorFundsToV3(uint128 amount) public {

tests/riskstewards/CapsPlusRiskSteward.t.sol

@@ -14,7 +14,7 @@ contract CapsPlusRiskSteward_Test is Test {
   CapsPlusRiskSteward public steward;
 
   function setUp() public {
-    vm.createSelectFork(vm.rpcUrl('mainnet'), 20933854);
+    vm.createSelectFork(vm.rpcUrl('mainnet'), 21923995);
     steward = new CapsPlusRiskSteward(
       AaveV3Ethereum.AAVE_PROTOCOL_DATA_PROVIDER,
       IAaveV3ConfigEngine(AaveV3Ethereum.CONFIG_ENGINE),