Moved error messages to error lib

contracts/lendingpool/LendingPool.sol

@@ -11,6 +11,7 @@ import {
 import {ILendingPoolAddressesProvider} from '../interfaces/ILendingPoolAddressesProvider.sol';
 import {IAToken} from '../tokenization/interfaces/IAToken.sol';
 import {Helpers} from '../libraries/helpers/Helpers.sol';
+import {Errors} from '../libraries/helpers/Errors.sol';
 import {WadRayMath} from '../libraries/math/WadRayMath.sol';
 import {ReserveLogic} from '../libraries/logic/ReserveLogic.sol';
 import {GenericLogic} from '../libraries/logic/GenericLogic.sol';
@@ -44,14 +45,6 @@ contract LendingPool is ReentrancyGuard, VersionedInitializable, ILendingPool {
   uint256 public constant MAX_STABLE_RATE_BORROW_SIZE_PERCENT = 25;
   uint256 public constant FLASHLOAN_FEE_TOTAL = 9;
 
-  //require error messages
-  string private constant NOT_ENOUGH_STABLE_BORROW_BALANCE = '1'; // 'User does not have any stable rate loan for this reserve'
-  string private constant INTERESTRATE_REBALANCE_CONDITIONS_NOT_MET = '2'; // 'Interest rate rebalance conditions were not met'
-  string private constant LIQUIDATION_CALL_FAILED = '3'; // 'Liquidation call failed'
-  string private constant NOT_ENOUGH_LIQUIDITY_TO_BORROW = '4'; // 'There is not enough liquidity available to borrow'
-  string private constant REQUESTED_AMOUNT_TO_SMALL = '5'; // 'The requested amount is too small for a FlashLoan.'
-  string private constant INCONSISTENT_PROTOCOL_ACTUAL_BALANCE = '6'; // 'The actual balance of the protocol is inconsistent'
-
   ILendingPoolAddressesProvider internal _addressesProvider;
 
   mapping(address => ReserveLogic.ReserveData) internal _reserves;

contracts/libraries/helpers/Errors.sol

@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: agpl-3.0
+pragma solidity ^0.6.8;
+
+/**
+ * @title Errors library
+ * @author Aave
+ * @notice Implements error messages.
+ */
+library Errors {
+  // require error messages - ValidationLogic
+  string private constant AMOUNT_NOT_GREATER_THAN_0 = '1'; // 'Amount must be greater than 0'
+  string private constant NO_ACTIVE_RESERVE = '2'; // 'Action requires an active reserve'
+  string private constant NO_UNFREEZED_RESERVE = '3'; // 'Action requires an unfreezed reserve'
+  string private constant CURRENT_AVAILABLE_LIQUIDITY_NOT_ENOUGH = '4'; // 'The current liquidity is not enough'
+  string private constant NOT_ENOUGH_AVAILABLE_USER_BALANCE = '5'; // 'User cannot withdraw more than the available balance'
+  string private constant TRANSFER_NOT_ALLOWED = '6'; // 'Transfer cannot be allowed.'
+  string private constant BORROWING_NOT_ENABLED = '7'; // 'Borrowing is not enabled'
+  string private constant INVALID_INTERESTRATE_MODE_SELECTED = '8'; // 'Invalid interest rate mode selected'
+  string private constant COLLATERAL_BALANCE_IS_0 = '9'; // 'The collateral balance is 0'
+  string private constant HEALTH_FACTOR_LOWER_THAN_LIQUIDATION_THRESHOLD = '10'; // 'Health factor is lesser than the liquidation threshold'
+  string private constant COLLATERAL_CANNOT_COVER_NEW_BORROW = '11'; // 'There is not enough collateral to cover a new borrow'
+  string private constant STABLE_BORROWING_NOT_ENABLED = '12'; // stable borrowing not enabled
+  string private constant CALLATERAL_SAME_AS_BORROWING_CURRENCY = '13'; // collateral is (mostly) the same currency that is being borrowed
+  string private constant AMOUNT_BIGGER_THAN_MAX_LOAN_SIZE_STABLE = '14'; // 'The requested amount is greater than the max loan size in stable rate mode
+  string private constant NO_DEBT_OF_SELECTED_TYPE = '15'; // 'for repayment of stable debt, the user needs to have stable debt, otherwise, he needs to have variable debt'
+  string private constant NO_EPLICIT_AMOUNT_TO_REPAY_ON_BEHALF = '16'; // 'To repay on behalf of an user an explicit amount to repay is needed'
+  string private constant NO_STABLE_RATE_LOAN_IN_RESERVE = '17'; // 'User does not have a stable rate loan in progress on this reserve'
+  string private constant NO_VARIABLE_RATE_LOAN_IN_RESERVE = '18'; // 'User does not have a variable rate loan in progress on this reserve'
+  string private constant UNDERLYING_BALANCE_NOT_GREATER_THAN_0 = '19'; // 'The underlying balance needs to be greater than 0'
+  string private constant DEPOSIT_ALREADY_IN_USE = '20'; // 'User deposit is already being used as collateral'
+
+  // require error messages - LendingPool
+  string private constant NOT_ENOUGH_STABLE_BORROW_BALANCE = '21'; // 'User does not have any stable rate loan for this reserve'
+  string private constant INTERESTRATE_REBALANCE_CONDITIONS_NOT_MET = '22'; // 'Interest rate rebalance conditions were not met'
+  string private constant LIQUIDATION_CALL_FAILED = '23'; // 'Liquidation call failed'
+  string private constant NOT_ENOUGH_LIQUIDITY_TO_BORROW = '24'; // 'There is not enough liquidity available to borrow'
+  string private constant REQUESTED_AMOUNT_TO_SMALL = '25'; // 'The requested amount is too small for a FlashLoan.'
+  string private constant INCONSISTENT_PROTOCOL_ACTUAL_BALANCE = '26'; // 'The actual balance of the protocol is inconsistent'
+
+  // require error messages - aToken
+  string private constant CALLER_MUST_BE_LENDING_POOL = '27'; // 'The caller of this function must be a lending pool'
+  string private constant TRANSFER_CANNOT_BE_ALLOWED = '28'; // 'Transfer cannot be allowed.'
+  string private constant NOT_ALLOWED_TO_REDIRECT_INTEREST = '29'; // 'Caller is not allowed to redirect the interest of the user'
+  string private constant CANNOT_GIVE_ALLOWANCE_TO_HIMSELF = '30'; // 'User cannot give allowance to himself'
+  string private constant TRANSFER_AMOUNT_NOT_GT_0 = '31'; // 'Transferred amount needs to be greater than zero'
+  string private constant INTEREST_ALREADY_REDIRECTED = '32'; // 'Interest is already redirected to the user'
+  string private constant NO_VALID_BALANCE_FOR_REDIRECT_INT_STREAM = '33'; // 'Interest stream can only be redirected if there is a valid balance'
+}

contracts/libraries/logic/ValidationLogic.sol

@@ -12,6 +12,7 @@ import {SafeERC20} from '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
 import {ReserveConfiguration} from '../configuration/ReserveConfiguration.sol';
 import {UserConfiguration} from '../configuration/UserConfiguration.sol';
 import {IPriceOracleGetter} from '../../interfaces/IPriceOracleGetter.sol';
+import {Errors} from '../libraries/helpers/Errors.sol';
 
 /**
  * @title ReserveLogic library
@@ -27,28 +28,6 @@ library ValidationLogic {
   using ReserveConfiguration for ReserveConfiguration.Map;
   using UserConfiguration for UserConfiguration.Map;
 
-  //require error messages
-  string private constant AMOUNT_NOT_GREATER_THAN_0 = '1'; // 'Amount must be greater than 0'
-  string private constant NO_ACTIVE_RESERVE = '2'; // 'Action requires an active reserve'
-  string private constant NO_UNFREEZED_RESERVE = '3'; // 'Action requires an unfreezed reserve'
-  string private constant CURRENT_AVAILABLE_LIQUIDITY_NOT_ENOUGH = '4'; // 'The current liquidity is not enough'
-  string private constant NOT_ENOUGH_AVAILABLE_USER_BALANCE = '5'; // 'User cannot withdraw more than the available balance'
-  string private constant TRANSFER_NOT_ALLOWED = '6'; // 'Transfer cannot be allowed.'
-  string private constant BORROWING_NOT_ENABLED = '7'; // 'Borrowing is not enabled'
-  string private constant INVALID_INTERESTRATE_MODE_SELECTED = '8'; // 'Invalid interest rate mode selected'
-  string private constant COLLATERAL_BALANCE_IS_0 = '9'; // 'The collateral balance is 0'
-  string private constant HEALTH_FACTOR_LOWER_THAN_LIQUIDATION_THRESHOLD = '10'; // 'Health factor is lesser than the liquidation threshold'
-  string private constant COLLATERAL_CANNOT_COVER_NEW_BORROW = '11'; // 'There is not enough collateral to cover a new borrow'
-  string private constant STABLE_BORROWING_NOT_ENABLED = '12'; // stable borrowing not enabled
-  string private constant CALLATERAL_SAME_AS_BORROWING_CURRENCY = '13'; // collateral is (mostly) the same currency that is being borrowed
-  string private constant AMOUNT_BIGGER_THAN_MAX_LOAN_SIZE_STABLE = '14'; // 'The requested amount is greater than the max loan size in stable rate mode
-  string private constant NO_DEBT_OF_SELECTED_TYPE = '15'; // 'for repayment of stable debt, the user needs to have stable debt, otherwise, he needs to have variable debt'
-  string private constant NO_EPLICIT_AMOUNT_TO_REPAY_ON_BEHALF = '16'; // 'To repay on behalf of an user an explicit amount to repay is needed'
-  string private constant NO_STABLE_RATE_LOAN_IN_RESERVE = '17'; // 'User does not have a stable rate loan in progress on this reserve'
-  string private constant NO_VARIABLE_RATE_LOAN_IN_RESERVE = '18'; // 'User does not have a variable rate loan in progress on this reserve'
-  string private constant UNDERLYING_BALANCE_NOT_GREATER_THAN_0 = '19'; // 'The underlying balance needs to be greater than 0'
-  string private constant DEPOSIT_ALREADY_IN_USE = '20'; // 'User deposit is already being used as collateral'
-
   /**
    * @dev validates a deposit.
    * @param reserve the reserve state on which the user is depositing

contracts/tokenization/AToken.sol

@@ -4,6 +4,7 @@ pragma solidity ^0.6.8;
 import {ERC20} from './ERC20.sol';
 import {LendingPool} from '../lendingpool/LendingPool.sol';
 import {WadRayMath} from '../libraries/math/WadRayMath.sol';
+import {Errors} from '../libraries/helpers/Errors';
 import {SafeERC20} from '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
 import {
   VersionedInitializable
@@ -34,12 +35,12 @@ contract AToken is VersionedInitializable, ERC20, IAToken {
   uint256 public constant ATOKEN_REVISION = 0x1;
 
   modifier onlyLendingPool {
-    require(msg.sender == address(_pool), 'The caller of this function must be a lending pool');
+    require(msg.sender == address(_pool), CALLER_MUST_BE_LENDING_POOL);
     _;
   }
 
   modifier whenTransferAllowed(address from, uint256 amount) {
-    require(isTransferAllowed(from, amount), 'Transfer cannot be allowed.');
+    require(isTransferAllowed(from, amount), TRANSFER_CANNOT_BE_ALLOWED);
     _;
   }
 
@@ -100,7 +101,7 @@ contract AToken is VersionedInitializable, ERC20, IAToken {
   function redirectInterestStreamOf(address from, address to) external override {
     require(
       msg.sender == _interestRedirectionAllowances[from],
-      'Caller is not allowed to redirect the interest of the user'
+      CALLER_NOT_ALLOWED_TO_REDIRECT_INTEREST
     );
     _redirectInterestStream(from, to);
   }
@@ -112,7 +113,7 @@ contract AToken is VersionedInitializable, ERC20, IAToken {
    * the allowance.
    **/
   function allowInterestRedirectionTo(address to) external override {
-    require(to != msg.sender, 'User cannot give allowance to himself');
+    require(to != msg.sender, CANNOT_GIVE_ALLOWANCE_TO_HIMSELF);
     _interestRedirectionAllowances[msg.sender] = to;
     emit InterestRedirectionAllowanceChanged(msg.sender, to);
   }
@@ -434,15 +435,12 @@ contract AToken is VersionedInitializable, ERC20, IAToken {
     address to,
     uint256 value
   ) internal {
-    require(value > 0, 'Transferred amount needs to be greater than zero');
+    require(value > 0, TRANSFER_AMOUNT_NOT_GT_0);
 
     //cumulate the balance of the sender
-    (
+    (, uint256 fromBalance, uint256 fromBalanceIncrease, uint256 fromIndex) = _cumulateBalance(
-      ,
+      from
-      uint256 fromBalance,
+    );
-      uint256 fromBalanceIncrease,
-      uint256 fromIndex
-    ) = _cumulateBalance(from);
 
     //cumulate the balance of the receiver
     (, , uint256 toBalanceIncrease, uint256 toIndex) = _cumulateBalance(to);
@@ -486,7 +484,7 @@ contract AToken is VersionedInitializable, ERC20, IAToken {
   function _redirectInterestStream(address from, address to) internal {
     address currentRedirectionAddress = _interestRedirectionAddresses[from];
 
-    require(to != currentRedirectionAddress, 'Interest is already redirected to the user');
+    require(to != currentRedirectionAddress, INTEREST_ALREADY_REDIRECTED);
 
     //accumulates the accrued interest to the principal
     (
@@ -496,7 +494,7 @@ contract AToken is VersionedInitializable, ERC20, IAToken {
       uint256 fromIndex
     ) = _cumulateBalance(from);
 
-    require(fromBalance > 0, 'Interest stream can only be redirected if there is a valid balance');
+    require(fromBalance > 0, NO_VALID_BALANCE_FOR_REDIRECT_INT_STREAM);
 
     //if the user is already redirecting the interest to someone, before changing
     //the redirection address we substract the redirected balance of the previous

helpers/types.ts

@@ -44,9 +44,50 @@ export enum eContractid {
 }
 
 export enum ProtocolErrors {
+  // require error messages - ValidationLogic
+  AMOUNT_NOT_GREATER_THAN_0 = '1', // 'Amount must be greater than 0'
+  NO_ACTIVE_RESERVE = '2', // 'Action requires an active reserve'
+  NO_UNFREEZED_RESERVE = '3', // 'Action requires an unfreezed reserve'
+  CURRENT_AVAILABLE_LIQUIDITY_NOT_ENOUGH = '4', // 'The current liquidity is not enough'
+  NOT_ENOUGH_AVAILABLE_USER_BALANCE = '5', // 'User cannot withdraw more than the available balance'
+  TRANSFER_NOT_ALLOWED = '6', // 'Transfer cannot be allowed.'
+  BORROWING_NOT_ENABLED = '7', // 'Borrowing is not enabled'
+  INVALID_INTERESTRATE_MODE_SELECTED = '8', // 'Invalid interest rate mode selected'
+  COLLATERAL_BALANCE_IS_0 = '9', // 'The collateral balance is 0'
+  HEALTH_FACTOR_LOWER_THAN_LIQUIDATION_THRESHOLD = '10', // 'Health factor is lesser than the liquidation threshold'
+  COLLATERAL_CANNOT_COVER_NEW_BORROW = '11', // 'There is not enough collateral to cover a new borrow'
+  STABLE_BORROWING_NOT_ENABLED = '12', // stable borrowing not enabled
+  CALLATERAL_SAME_AS_BORROWING_CURRENCY = '13', // collateral is (mostly) the same currency that is being borrowed
+  AMOUNT_BIGGER_THAN_MAX_LOAN_SIZE_STABLE = '14', // 'The requested amount is greater than the max loan size in stable rate mode
+  NO_DEBT_OF_SELECTED_TYPE = '15', // 'for repayment of stable debt, the user needs to have stable debt, otherwise, he needs to have variable debt'
+  NO_EPLICIT_AMOUNT_TO_REPAY_ON_BEHALF = '16', // 'To repay on behalf of an user an explicit amount to repay is needed'
+  NO_STABLE_RATE_LOAN_IN_RESERVE = '17', // 'User does not have a stable rate loan in progress on this reserve'
+  NO_VARIABLE_RATE_LOAN_IN_RESERVE = '18', // 'User does not have a variable rate loan in progress on this reserve'
+  UNDERLYING_BALANCE_NOT_GREATER_THAN_0 = '19', // 'The underlying balance needs to be greater than 0'
+  DEPOSIT_ALREADY_IN_USE = '20', // 'User deposit is already being used as collateral'
+
+  // require error messages - LendingPool
+  NOT_ENOUGH_STABLE_BORROW_BALANCE = '21', // 'User does not have any stable rate loan for this reserve'
+  INTERESTRATE_REBALANCE_CONDITIONS_NOT_MET = '22', // 'Interest rate rebalance conditions were not met'
+  LIQUIDATION_CALL_FAILED = '23', // 'Liquidation call failed'
+  NOT_ENOUGH_LIQUIDITY_TO_BORROW = '24', // 'There is not enough liquidity available to borrow'
+  REQUESTED_AMOUNT_TO_SMALL = '25', // 'The requested amount is too small for a FlashLoan.'
+  INCONSISTENT_PROTOCOL_ACTUAL_BALANCE = '26', // 'The actual balance of the protocol is inconsistent'
+
+  // require error messages - aToken
+  CALLER_MUST_BE_LENDING_POOL = '27', // 'The caller of this function must be a lending pool'
+  TRANSFER_CANNOT_BE_ALLOWED = '28', // 'Transfer cannot be allowed.'
+  NOT_ALLOWED_TO_REDIRECT_INTEREST = '29', // 'Caller is not allowed to redirect the interest of the user'
+  CANNOT_GIVE_ALLOWANCE_TO_HIMSELF = '30', // 'User cannot give allowance to himself'
+  TRANSFER_AMOUNT_NOT_GT_0 = '31', // 'Transferred amount needs to be greater than zero'
+  INTEREST_ALREADY_REDIRECTED = '32', // 'Interest is already redirected to the user'
+  NO_VALID_BALANCE_FOR_REDIRECT_INT_STREAM = '33', // 'Interest stream can only be redirected if there is a valid balance'
+}
+
+export enum OLD_ProtocolErrors {
   INVALID_CONFIGURATOR_CALLER_MSG = 'The caller must be a lending pool configurator contract',
   INVALID_POOL_CALLER_MSG = 'The caller must be a lending pool contract',
-  INVALID_POOL_CALLER_MSG_1 = 'The caller of this function must be a lending pool',
+  // INVALID_POOL_CALLER_MSG_1 = 'The caller of this function must be a lending pool', => CALLER_MUST_BE_LENDING_POOL
   INVALID_POOL_MANAGER_CALLER_MSG = 'The caller must be a lending pool manager',
   INVALID_FROM_BALANCE_AFTER_TRANSFER = 'Invalid from balance after transfer',
   INVALID_TO_BALANCE_AFTER_TRANSFER = 'Invalid from balance after transfer',

test/atoken-modifiers.spec.ts

@@ -3,17 +3,17 @@ import {makeSuite, TestEnv} from './helpers/make-suite';
 import {ProtocolErrors} from '../helpers/types';
 
 makeSuite('AToken: Modifiers', (testEnv: TestEnv) => {
-  const {INVALID_POOL_CALLER_MSG_1} = ProtocolErrors;
+  const {CALLER_MUST_BE_LENDING_POOL} = ProtocolErrors;
 
   it('Tries to invoke mint not being the LendingPool', async () => {
     const {deployer, aDai} = testEnv;
-    await expect(aDai.mint(deployer.address, '1')).to.be.revertedWith(INVALID_POOL_CALLER_MSG_1);
+    await expect(aDai.mint(deployer.address, '1')).to.be.revertedWith(CALLER_MUST_BE_LENDING_POOL);
   });
 
   it('Tries to invoke burn not being the LendingPool', async () => {
     const {deployer, aDai} = testEnv;
     await expect(aDai.burn(deployer.address, deployer.address, '1')).to.be.revertedWith(
-      INVALID_POOL_CALLER_MSG_1
+      CALLER_MUST_BE_LENDING_POOL
     );
   });
 
@@ -21,13 +21,13 @@ makeSuite('AToken: Modifiers', (testEnv: TestEnv) => {
     const {deployer, users, aDai} = testEnv;
     await expect(
       aDai.transferOnLiquidation(deployer.address, users[0].address, '1')
-    ).to.be.revertedWith(INVALID_POOL_CALLER_MSG_1);
+    ).to.be.revertedWith(CALLER_MUST_BE_LENDING_POOL);
   });
 
   it('Tries to invoke transferUnderlyingTo not being the LendingPool', async () => {
     const {deployer, users, aDai} = testEnv;
     await expect(aDai.transferUnderlyingTo(deployer.address, '1')).to.be.revertedWith(
-      INVALID_POOL_CALLER_MSG_1
+      CALLER_MUST_BE_LENDING_POOL
     );
   });
 });