initial changes + test

contracts/interfaces/ILendingPool.sol

@@ -15,7 +15,8 @@ interface ILendingPool {
    **/
   event Deposit(
     address indexed reserve,
-    address indexed user,
+    address user,
+    address indexed onBehalfOf,
     uint256 amount,
     uint16 indexed referral
   );
@@ -139,6 +140,7 @@ interface ILendingPool {
   function deposit(
     address reserve,
     uint256 amount,
+    address onBehalfOf,
     uint16 referralCode
   ) external;
 

contracts/lendingpool/LendingPool.sol

@@ -89,6 +89,7 @@ contract LendingPool is VersionedInitializable, ILendingPool {
   function deposit(
     address asset,
     uint256 amount,
+    address onBehalfOf,
     uint16 referralCode
   ) external override {
     ReserveLogic.ReserveData storage reserve = _reserves[asset];
@@ -100,18 +101,18 @@ contract LendingPool is VersionedInitializable, ILendingPool {
     reserve.updateCumulativeIndexesAndTimestamp();
     reserve.updateInterestRates(asset, aToken, amount, 0);
 
-    bool isFirstDeposit = IAToken(aToken).balanceOf(msg.sender) == 0;
+    bool isFirstDeposit = IAToken(aToken).balanceOf(onBehalfOf) == 0;
     if (isFirstDeposit) {
-      _usersConfig[msg.sender].setUsingAsCollateral(reserve.index, true);
+      _usersConfig[onBehalfOf].setUsingAsCollateral(reserve.index, true);
     }
 
     //minting AToken to user 1:1 with the specific exchange rate
-    IAToken(aToken).mint(msg.sender, amount);
+    IAToken(aToken).mint(onBehalfOf, amount);
 
     //transfer to the aToken contract
     IERC20(asset).safeTransferFrom(msg.sender, aToken, amount);
 
-    emit Deposit(asset, msg.sender, amount, referralCode);
+    emit Deposit(asset, msg.sender, onBehalfOf, amount, referralCode);
   }
 
   /**
@@ -450,15 +451,13 @@ contract LendingPool is VersionedInitializable, ILendingPool {
     vars.amountPlusPremium = amount.add(vars.premium);
 
     if (debtMode == ReserveLogic.InterestRateMode.NONE) {
-      
       IERC20(asset).transferFrom(receiverAddress, vars.aTokenAddress, vars.amountPlusPremium);
-      
+
       reserve.updateCumulativeIndexesAndTimestamp();
       reserve.cumulateToLiquidityIndex(IERC20(vars.aTokenAddress).totalSupply(), vars.premium);
       reserve.updateInterestRates(asset, vars.aTokenAddress, vars.premium, 0);
-      
-      emit FlashLoan(receiverAddress, asset, amount, vars.premium, referralCode);
 
+      emit FlashLoan(receiverAddress, asset, amount, vars.premium, referralCode);
     } else {
       // If the transfer didn't succeed, the receiver either didn't return the funds, or didn't approve the transfer.
       _executeBorrow(
@@ -728,13 +727,11 @@ contract LendingPool is VersionedInitializable, ILendingPool {
       oracle
     );
 
-
     uint256 reserveIndex = reserve.index;
     if (!userConfig.isBorrowing(reserveIndex)) {
       userConfig.setBorrowing(reserveIndex, true);
     }
 
-
     reserve.updateCumulativeIndexesAndTimestamp();
 
     //caching the current stable borrow rate
@@ -754,13 +751,17 @@ contract LendingPool is VersionedInitializable, ILendingPool {
       IVariableDebtToken(reserve.variableDebtTokenAddress).mint(vars.user, vars.amount);
     }
 
-    reserve.updateInterestRates(vars.asset, vars.aTokenAddress, 0, vars.releaseUnderlying ?  vars.amount : 0);
+    reserve.updateInterestRates(
-  
+      vars.asset,
-    if(vars.releaseUnderlying){
+      vars.aTokenAddress,
-        IAToken(vars.aTokenAddress).transferUnderlyingTo(msg.sender, vars.amount);
+      0,
+      vars.releaseUnderlying ? vars.amount : 0
+    );
+
+    if (vars.releaseUnderlying) {
+      IAToken(vars.aTokenAddress).transferUnderlyingTo(msg.sender, vars.amount);
     }
-  
+
-  
     emit Borrow(
       vars.asset,
       msg.sender,

package.json

@@ -13,7 +13,7 @@
     "types-gen": "typechain --target ethers-v5 --outDir ./types './artifacts/*.json'",
     "test": "buidler test",
     "test-scenarios": "buidler test test/__setup.spec.ts test/scenario.spec.ts",
-    "test-flash": "buidler test test/__setup.spec.ts test/flashloan.spec.ts",
+    "test-flash": "buidler test test/__setup.spec.ts test/collateral-swap.spec.ts",
     "dev:coverage": "buidler coverage",
     "dev:deployment": "buidler dev-deployment",
     "dev:deployExample": "buidler deploy-Example",

test/atoken-transfer.spec.ts

@@ -33,7 +33,9 @@ makeSuite('AToken: Transfer', (testEnv: TestEnv) => {
     //user 1 deposits 1000 DAI
     const amountDAItoDeposit = await convertToCurrencyDecimals(dai.address, '1000');
 
-    await pool.connect(users[0].signer).deposit(dai.address, amountDAItoDeposit, '0');
+    await pool
+      .connect(users[0].signer)
+      .deposit(dai.address, amountDAItoDeposit, users[0].address, '0');
 
     await aDai.connect(users[0].signer).transfer(users[1].address, amountDAItoDeposit);
 
@@ -94,12 +96,15 @@ makeSuite('AToken: Transfer', (testEnv: TestEnv) => {
 
   it('User 0 deposits 1 WETH and user 1 tries to borrow, but the aTokens received as a transfer are not available as collateral (revert expected)', async () => {
     const {users, pool, weth} = testEnv;
+    const userAddress = await pool.signer.getAddress();
 
     await weth.connect(users[0].signer).mint(await convertToCurrencyDecimals(weth.address, '1'));
 
     await weth.connect(users[0].signer).approve(pool.address, APPROVAL_AMOUNT_LENDING_POOL);
 
-    await pool.connect(users[0].signer).deposit(weth.address, ethers.utils.parseEther('1.0'), '0');
+    await pool
+      .connect(users[0].signer)
+      .deposit(weth.address, ethers.utils.parseEther('1.0'), userAddress, '0');
     await expect(
       pool
         .connect(users[1].signer)

test/configurator.spec.ts

@@ -234,7 +234,7 @@ makeSuite('LendingPoolConfigurator', (testEnv: TestEnv) => {
 
   it('Reverts when trying to disable the DAI reserve with liquidity on it', async () => {
     const {dai, pool, configurator} = testEnv;
-
+    const userAddress = await pool.signer.getAddress();
     await dai.mint(await convertToCurrencyDecimals(dai.address, '1000'));
 
     //approve protocol to access depositor wallet
@@ -242,7 +242,7 @@ makeSuite('LendingPoolConfigurator', (testEnv: TestEnv) => {
     const amountDAItoDeposit = await convertToCurrencyDecimals(dai.address, '1000');
 
     //user 1 deposits 1000 DAI
-    await pool.deposit(dai.address, amountDAItoDeposit, '0');
+    await pool.deposit(dai.address, amountDAItoDeposit, userAddress, '0');
 
     await expect(
       configurator.deactivateReserve(dai.address),

test/flashloan.spec.ts

@@ -30,13 +30,14 @@ makeSuite('LendingPool FlashLoan function', (testEnv: TestEnv) => {
 
   it('Deposits ETH into the reserve', async () => {
     const {pool, weth} = testEnv;
+    const userAddress = await pool.signer.getAddress();
     const amountToDeposit = ethers.utils.parseEther('1');
 
     await weth.mint(amountToDeposit);
 
     await weth.approve(pool.address, APPROVAL_AMOUNT_LENDING_POOL);
 
-    await pool.deposit(weth.address, amountToDeposit, '0');
+    await pool.deposit(weth.address, amountToDeposit, userAddress, '0');
   });
 
   it('Takes WETH flashloan with mode = 0, returns the funds correctly', async () => {
@@ -143,7 +144,7 @@ makeSuite('LendingPool FlashLoan function', (testEnv: TestEnv) => {
 
     const amountToDeposit = await convertToCurrencyDecimals(dai.address, '1000');
 
-    await pool.connect(caller.signer).deposit(dai.address, amountToDeposit, '0');
+    await pool.connect(caller.signer).deposit(dai.address, amountToDeposit, caller.address, '0');
 
     await _mockFlashLoanReceiver.setFailExecutionTransfer(true);
 
@@ -210,6 +211,7 @@ makeSuite('LendingPool FlashLoan function', (testEnv: TestEnv) => {
 
   it('Deposits USDC into the reserve', async () => {
     const {usdc, pool} = testEnv;
+    const userAddress = await pool.signer.getAddress();
 
     await usdc.mint(await convertToCurrencyDecimals(usdc.address, '1000'));
 
@@ -217,7 +219,7 @@ makeSuite('LendingPool FlashLoan function', (testEnv: TestEnv) => {
 
     const amountToDeposit = await convertToCurrencyDecimals(usdc.address, '1000');
 
-    await pool.deposit(usdc.address, amountToDeposit, '0');
+    await pool.deposit(usdc.address, amountToDeposit, userAddress, '0');
   });
 
   it('Takes out a 500 USDC flashloan, returns the funds correctly', async () => {
@@ -284,7 +286,7 @@ makeSuite('LendingPool FlashLoan function', (testEnv: TestEnv) => {
 
     const amountToDeposit = await convertToCurrencyDecimals(weth.address, '5');
 
-    await pool.connect(caller.signer).deposit(weth.address, amountToDeposit, '0');
+    await pool.connect(caller.signer).deposit(weth.address, amountToDeposit, caller.address, '0');
 
     await _mockFlashLoanReceiver.setFailExecutionTransfer(true);
 
@@ -307,7 +309,6 @@ makeSuite('LendingPool FlashLoan function', (testEnv: TestEnv) => {
 
   it('Caller deposits 1000 DAI as collateral, Takes a WETH flashloan with mode = 0, does not approve the transfer of the funds', async () => {
     const {dai, pool, weth, users} = testEnv;
-
     const caller = users[3];
 
     await dai.connect(caller.signer).mint(await convertToCurrencyDecimals(dai.address, '1000'));
@@ -316,7 +317,7 @@ makeSuite('LendingPool FlashLoan function', (testEnv: TestEnv) => {
 
     const amountToDeposit = await convertToCurrencyDecimals(dai.address, '1000');
 
-    await pool.connect(caller.signer).deposit(dai.address, amountToDeposit, '0');
+    await pool.connect(caller.signer).deposit(dai.address, amountToDeposit, caller.address, '0');
 
     const flashAmount = ethers.utils.parseEther('0.8');
 

test/helpers/actions.ts

@@ -133,7 +133,8 @@ export const approve = async (reserveSymbol: string, user: SignerWithAddress, te
 export const deposit = async (
   reserveSymbol: string,
   amount: string,
-  user: SignerWithAddress,
+  sender: SignerWithAddress,
+  onBehalfOf: tEthereumAddress,
   sendValue: string,
   expectedResult: string,
   testEnv: TestEnv,
@@ -149,8 +150,9 @@ export const deposit = async (
 
   const {reserveData: reserveDataBefore, userData: userDataBefore} = await getContractsData(
     reserve,
-    user.address,
+    onBehalfOf,
-    testEnv
+    testEnv,
+    sender.address
   );
 
   if (sendValue) {
@@ -158,14 +160,16 @@ export const deposit = async (
   }
   if (expectedResult === 'success') {
     const txResult = await waitForTx(
-      await await pool.connect(user.signer).deposit(reserve, amountToDeposit, '0', txOptions)
+      await pool
+        .connect(sender.signer)
+        .deposit(reserve, amountToDeposit, onBehalfOf, '0', txOptions)
     );
 
     const {
       reserveData: reserveDataAfter,
       userData: userDataAfter,
       timestamp,
-    } = await getContractsData(reserve, user.address, testEnv);
+    } = await getContractsData(reserve, onBehalfOf, testEnv, sender.address);
 
     const {txCost, txTimestamp} = await getTxCostAndTimestamp(txResult);
 
@@ -198,7 +202,7 @@ export const deposit = async (
     // });
   } else if (expectedResult === 'revert') {
     await expect(
-      pool.connect(user.signer).deposit(reserve, amountToDeposit, '0', txOptions),
+      pool.connect(sender.signer).deposit(reserve, amountToDeposit, onBehalfOf, '0', txOptions),
       revertMessage
     ).to.be.reverted;
   }
@@ -845,10 +849,15 @@ const getTxCostAndTimestamp = async (tx: ContractReceipt) => {
   return {txCost, txTimestamp};
 };
 
-const getContractsData = async (reserve: string, user: string, testEnv: TestEnv) => {
+const getContractsData = async (
+  reserve: string,
+  user: string,
+  testEnv: TestEnv,
+  sender?: string
+) => {
   const {pool} = testEnv;
   const reserveData = await getReserveData(pool, reserve);
-  const userData = await getUserData(pool, reserve, user);
+  const userData = await getUserData(pool, reserve, user, sender || user);
   const timestamp = await timeLatest();
 
   return {

test/helpers/scenario-engine.ts

@@ -92,13 +92,25 @@ const executeAction = async (action: Action, users: SignerWithAddress[], testEnv
 
     case 'deposit':
       {
-        const {amount, sendValue} = action.args;
+        const {amount, sendValue, onBehalfOf: onBehalfOfIndex} = action.args;
+        const onBehalfOf = onBehalfOfIndex
+          ? users[parseInt(onBehalfOfIndex)].address
+          : user.address;
 
         if (!amount || amount === '') {
           throw `Invalid amount to deposit into the ${reserve} reserve`;
         }
 
-        await deposit(reserve, amount, user, sendValue, expected, testEnv, revertMessage);
+        await deposit(
+          reserve,
+          amount,
+          user,
+          onBehalfOf,
+          sendValue,
+          expected,
+          testEnv,
+          revertMessage
+        );
       }
       break;
 

test/helpers/scenarios/deposit.json

@@ -206,7 +206,6 @@
           "name": "deposit",
           "args": {
             "reserve": "WETH",
-
             "amount": "0",
             "user": "1"
           },
@@ -229,6 +228,40 @@
           "revertMessage": "Amount must be greater than 0"
         }
       ]
+    },
+    {
+      "description": "User 1 deposits 100 DAI on behalf of user 2, user 2 tries to borrow 0.1 WETH",
+      "actions": [
+        {
+          "name": "mint",
+          "args": {
+            "reserve": "DAI",
+            "amount": "100",
+            "user": "1"
+          },
+          "expected": "success"
+        },
+        {
+          "name": "deposit",
+          "args": {
+            "reserve": "DAI",
+            "amount": "100",
+            "user": "1",
+            "onBehalfOf": "2"
+          },
+          "expected": "success"
+        },
+        {
+          "name": "borrow",
+          "args": {
+            "reserve": "WETH",
+            "amount": "0.1",
+            "borrowRateMode": "variable",
+            "user": "2"
+          },
+          "expected": "success"
+        }
+      ]
     }
   ]
 }

test/helpers/utils/helpers.ts

@@ -61,7 +61,8 @@ export const getReserveData = async (
 export const getUserData = async (
   pool: LendingPool,
   reserve: string,
-  user: string
+  user: tEthereumAddress,
+  sender?: tEthereumAddress
 ): Promise<UserReserveData> => {
   const [userData, aTokenData] = await Promise.all([
     pool.getUserReserveData(reserve, user),
@@ -77,7 +78,7 @@ export const getUserData = async (
   ] = aTokenData;
 
   const token = await getMintableErc20(reserve);
-  const walletBalance = new BigNumber((await token.balanceOf(user)).toString());
+  const walletBalance = new BigNumber((await token.balanceOf(sender || user)).toString());
 
   return {
     principalATokenBalance: new BigNumber(principalATokenBalance),

test/liquidation-atoken.spec.ts

@@ -32,7 +32,9 @@ makeSuite('LendingPool liquidation - liquidator receiving aToken', (testEnv) =>
 
     //user 1 deposits 1000 DAI
     const amountDAItoDeposit = await convertToCurrencyDecimals(dai.address, '1000');
-    await pool.connect(depositor.signer).deposit(dai.address, amountDAItoDeposit, '0');
+    await pool
+      .connect(depositor.signer)
+      .deposit(dai.address, amountDAItoDeposit, depositor.address, '0');
 
     const amountETHtoDeposit = await convertToCurrencyDecimals(weth.address, '1');
 
@@ -43,7 +45,9 @@ makeSuite('LendingPool liquidation - liquidator receiving aToken', (testEnv) =>
     await weth.connect(borrower.signer).approve(pool.address, APPROVAL_AMOUNT_LENDING_POOL);
 
     //user 2 deposits 1 WETH
-    await pool.connect(borrower.signer).deposit(weth.address, amountETHtoDeposit, '0');
+    await pool
+      .connect(borrower.signer)
+      .deposit(weth.address, amountETHtoDeposit, borrower.address, '0');
 
     //user 2 borrows
     const userGlobalData = await pool.getUserAccountData(borrower.address);
@@ -224,7 +228,9 @@ makeSuite('LendingPool liquidation - liquidator receiving aToken', (testEnv) =>
     //user 3 deposits 1000 USDC
     const amountUSDCtoDeposit = await convertToCurrencyDecimals(usdc.address, '1000');
 
-    await pool.connect(depositor.signer).deposit(usdc.address, amountUSDCtoDeposit, '0');
+    await pool
+      .connect(depositor.signer)
+      .deposit(usdc.address, amountUSDCtoDeposit, depositor.address, '0');
 
     //user 4 deposits 1 ETH
     const amountETHtoDeposit = await convertToCurrencyDecimals(weth.address, '1');
@@ -235,7 +241,9 @@ makeSuite('LendingPool liquidation - liquidator receiving aToken', (testEnv) =>
     //approve protocol to access borrower wallet
     await weth.connect(borrower.signer).approve(pool.address, APPROVAL_AMOUNT_LENDING_POOL);
 
-    await pool.connect(borrower.signer).deposit(weth.address, amountETHtoDeposit, '0');
+    await pool
+      .connect(borrower.signer)
+      .deposit(weth.address, amountETHtoDeposit, borrower.address, '0');
 
     //user 4 borrows
     const userGlobalData = await pool.getUserAccountData(borrower.address);

test/liquidation-underlying.spec.ts

@@ -29,7 +29,9 @@ makeSuite('LendingPool liquidation - liquidator receiving the underlying asset',
     //user 1 deposits 1000 DAI
     const amountDAItoDeposit = await convertToCurrencyDecimals(dai.address, '1000');
 
-    await pool.connect(depositor.signer).deposit(dai.address, amountDAItoDeposit, '0');
+    await pool
+      .connect(depositor.signer)
+      .deposit(dai.address, amountDAItoDeposit, depositor.address, '0');
     //user 2 deposits 1 ETH
     const amountETHtoDeposit = await convertToCurrencyDecimals(weth.address, '1');
 
@@ -39,7 +41,9 @@ makeSuite('LendingPool liquidation - liquidator receiving the underlying asset',
     //approve protocol to access the borrower wallet
     await weth.connect(borrower.signer).approve(pool.address, APPROVAL_AMOUNT_LENDING_POOL);
 
-    await pool.connect(borrower.signer).deposit(weth.address, amountETHtoDeposit, '0');
+    await pool
+      .connect(borrower.signer)
+      .deposit(weth.address, amountETHtoDeposit, borrower.address, '0');
 
     //user 2 borrows
 
@@ -194,7 +198,9 @@ makeSuite('LendingPool liquidation - liquidator receiving the underlying asset',
     //depositor deposits 1000 USDC
     const amountUSDCtoDeposit = await convertToCurrencyDecimals(usdc.address, '1000');
 
-    await pool.connect(depositor.signer).deposit(usdc.address, amountUSDCtoDeposit, '0');
+    await pool
+      .connect(depositor.signer)
+      .deposit(usdc.address, amountUSDCtoDeposit, depositor.address, '0');
 
     //borrower deposits 1 ETH
     const amountETHtoDeposit = await convertToCurrencyDecimals(weth.address, '1');
@@ -205,7 +211,9 @@ makeSuite('LendingPool liquidation - liquidator receiving the underlying asset',
     //approve protocol to access the borrower wallet
     await weth.connect(borrower.signer).approve(pool.address, APPROVAL_AMOUNT_LENDING_POOL);
 
-    await pool.connect(borrower.signer).deposit(weth.address, amountETHtoDeposit, '0');
+    await pool
+      .connect(borrower.signer)
+      .deposit(weth.address, amountETHtoDeposit, borrower.address, '0');
 
     //borrower borrows
     const userGlobalData = await pool.getUserAccountData(borrower.address);
@@ -334,7 +342,9 @@ makeSuite('LendingPool liquidation - liquidator receiving the underlying asset',
     //borrower deposits 1000 LEND
     const amountLENDtoDeposit = await convertToCurrencyDecimals(lend.address, '1000');
 
-    await pool.connect(borrower.signer).deposit(lend.address, amountLENDtoDeposit, '0');
+    await pool
+      .connect(borrower.signer)
+      .deposit(lend.address, amountLENDtoDeposit, borrower.address, '0');
     const usdcPrice = await oracle.getAssetPrice(usdc.address);
 
     //drops HF below 1