Refactored reservesList to a mapping

contracts/interfaces/ILendingPool.sol

@@ -428,7 +428,7 @@ interface ILendingPool {
     uint256 amount
   ) external view returns (bool);
 
-  function getReserves() external view returns (address[] memory);
+  function getReservesList() external view returns (address[] memory);
 
   /**
    * @dev Set the _pause state

contracts/lendingpool/LendingPool.sol

@@ -144,6 +144,7 @@ contract LendingPool is VersionedInitializable, ILendingPool, LendingPoolStorage
       _reserves,
       _usersConfig[msg.sender],
       _reservesList,
+      _reservesCount,
       _addressesProvider.getPriceOracle()
     );
 
@@ -424,6 +425,7 @@ contract LendingPool is VersionedInitializable, ILendingPool, LendingPoolStorage
       _reserves,
       _usersConfig[msg.sender],
       _reservesList,
+      _reservesCount,
       _addressesProvider.getPriceOracle()
     );
 
@@ -753,6 +755,7 @@ contract LendingPool is VersionedInitializable, ILendingPool, LendingPoolStorage
       _reserves,
       _usersConfig[user],
       _reservesList,
+      _reservesCount,
       _addressesProvider.getPriceOracle()
     );
     
@@ -793,10 +796,6 @@ contract LendingPool is VersionedInitializable, ILendingPool, LendingPoolStorage
     usageAsCollateralEnabled = _usersConfig[user].isUsingAsCollateral(reserve.id);
   }
 
-  function getReserves() external override view returns (address[] memory) {
-    return _reservesList;
-  }
-
   receive() external payable {
     revert();
   }
@@ -889,6 +888,7 @@ contract LendingPool is VersionedInitializable, ILendingPool, LendingPoolStorage
       _reserves,
       userConfig,
       _reservesList,
+      _reservesCount,
       oracle
     );
 
@@ -948,16 +948,13 @@ contract LendingPool is VersionedInitializable, ILendingPool, LendingPoolStorage
    * @dev adds a reserve to the array of the _reserves address
    **/
   function _addReserveToList(address asset) internal {
-    bool reserveAlreadyAdded = false;
-    require(_reservesList.length < MAX_NUMBER_RESERVES, Errors.NO_MORE_RESERVES_ALLOWED);
-    for (uint256 i = 0; i < _reservesList.length; i++)
-      if (_reservesList[i] == asset) {
-        reserveAlreadyAdded = true;
-      }
-    if (!reserveAlreadyAdded) {
-      _reserves[asset].id = uint8(_reservesList.length);
-      _reservesList.push(asset);
-    }
+    
+    require(_reservesCount < MAX_NUMBER_RESERVES, Errors.NO_MORE_RESERVES_ALLOWED);
+  
+      _reserves[asset].id = uint8(_reservesCount);
+      _reservesList[_reservesCount] = asset;
+
+      _reservesCount++;
   }
 
   /**
@@ -1004,6 +1001,7 @@ contract LendingPool is VersionedInitializable, ILendingPool, LendingPoolStorage
         _reserves,
         _usersConfig[user],
         _reservesList,
+        _reservesCount,
         _addressesProvider.getPriceOracle()
       );
   }
@@ -1029,4 +1027,23 @@ contract LendingPool is VersionedInitializable, ILendingPool, LendingPoolStorage
   function paused() external override view returns (bool) {
     return _paused;
   }
+
+  /**
+   * @dev returns the list of the initialized reserves
+   **/
+  function getReservesList() external override view returns (address[] memory) {
+    address[] memory _activeReserves = new address[](_reservesCount);
+
+    for(uint256 i = 0; i < _reservesCount; i++){
+      _activeReserves[i] = _reservesList[i];
+    }
+    return _activeReserves;
+  }
+
+  /**
+   * @dev returns the addresses provider
+   **/
+  function getAddressesProvider() external view returns (ILendingPoolAddressesProvider) {
+    return _addressesProvider;
+  }
 }

contracts/lendingpool/LendingPoolCollateralManager.sol

@@ -154,6 +154,7 @@ contract LendingPoolCollateralManager is VersionedInitializable, LendingPoolStor
       _reserves,
       _usersConfig[user],
       _reservesList,
+      _reservesCount,
       _addressesProvider.getPriceOracle()
     );
 
@@ -325,6 +326,7 @@ contract LendingPoolCollateralManager is VersionedInitializable, LendingPoolStor
       _reserves,
       _usersConfig[user],
       _reservesList,
+      _reservesCount,
       _addressesProvider.getPriceOracle()
     );
 
@@ -412,7 +414,11 @@ contract LendingPoolCollateralManager is VersionedInitializable, LendingPoolStor
       vars.actualAmountToLiquidate,
       0
     );
-    IERC20(principal).safeTransferFrom(receiver, vars.principalAToken, vars.actualAmountToLiquidate);
+    IERC20(principal).safeTransferFrom(
+      receiver,
+      vars.principalAToken,
+      vars.actualAmountToLiquidate
+    );
 
     if (vars.userVariableDebt >= vars.actualAmountToLiquidate) {
       IVariableDebtToken(debtReserve.variableDebtTokenAddress).burn(
@@ -528,6 +534,7 @@ contract LendingPoolCollateralManager is VersionedInitializable, LendingPoolStor
       _reserves,
       _usersConfig[msg.sender],
       _reservesList,
+      _reservesCount,
       _addressesProvider.getPriceOracle()
     );
 

contracts/lendingpool/LendingPoolStorage.sol

@@ -18,22 +18,12 @@ contract LendingPoolStorage {
   // debt token address => user who gives allowance => user who receives allowance => amount
   mapping(address => mapping(address => mapping(address => uint256))) internal _borrowAllowance;
 
-  address[] internal _reservesList;
+  // the list of the available reserves, structured as a mapping for gas savings reasons
+  mapping(uint256 => address) internal _reservesList;
+
+  uint256 internal _reservesCount;
 
   bool internal _flashLiquidationLocked;
   bool internal _paused;
 
-  /**
-   * @dev returns the list of the initialized reserves
-   **/
-  function getReservesList() external view returns (address[] memory) {
-    return _reservesList;
-  }
-
-  /**
-   * @dev returns the addresses provider
-   **/
-  function getAddressesProvider() external view returns (ILendingPoolAddressesProvider) {
-    return _addressesProvider;
-  }
 }

contracts/libraries/logic/GenericLogic.sol

@@ -58,7 +58,8 @@ library GenericLogic {
     uint256 amount,
     mapping(address => ReserveLogic.ReserveData) storage reservesData,
     UserConfiguration.Map calldata userConfig,
-    address[] calldata reserves,
+    mapping(uint256 => address) storage reserves,
+    uint256 reservesCount,
     address oracle
   ) external view returns (bool) {
     if (!userConfig.isBorrowingAny() || !userConfig.isUsingAsCollateral(reservesData[asset].id)) {
@@ -79,7 +80,7 @@ library GenericLogic {
       ,
       vars.avgLiquidationThreshold,
 
-    ) = calculateUserAccountData(user, reservesData, userConfig, reserves, oracle);
+    ) = calculateUserAccountData(user, reservesData, userConfig, reserves, reservesCount, oracle);
 
     if (vars.borrowBalanceETH == 0) {
       return true; //no borrows - no reasons to block the transfer
@@ -149,7 +150,8 @@ library GenericLogic {
     address user,
     mapping(address => ReserveLogic.ReserveData) storage reservesData,
     UserConfiguration.Map memory userConfig,
-    address[] memory reserves,
+    mapping(uint256 => address) storage reserves,
+    uint256 reservesCount,
     address oracle
   )
     internal
@@ -167,7 +169,7 @@ library GenericLogic {
     if (userConfig.isEmpty()) {
       return (0, 0, 0, 0, uint256(-1));
     }
-    for (vars.i = 0; vars.i < reserves.length; vars.i++) {
+    for (vars.i = 0; vars.i < reservesCount; vars.i++) {
       if (!userConfig.isUsingAsCollateralOrBorrowing(vars.i)) {
         continue;
       }

contracts/libraries/logic/ValidationLogic.sol

@@ -54,7 +54,8 @@ library ValidationLogic {
     uint256 userBalance,
     mapping(address => ReserveLogic.ReserveData) storage reservesData,
     UserConfiguration.Map storage userConfig,
-    address[] calldata reserves,
+    mapping(uint256 => address) storage reserves,
+    uint256 reservesCount,
     address oracle
   ) external view {
     require(amount > 0, Errors.AMOUNT_NOT_GREATER_THAN_0);
@@ -69,6 +70,7 @@ library ValidationLogic {
         reservesData,
         userConfig,
         reserves,
+        reservesCount,
         oracle
       ),
       Errors.TRANSFER_NOT_ALLOWED
@@ -119,7 +121,8 @@ library ValidationLogic {
     uint256 maxStableLoanPercent,
     mapping(address => ReserveLogic.ReserveData) storage reservesData,
     UserConfiguration.Map storage userConfig,
-    address[] calldata reserves,
+    mapping(uint256 => address) storage reserves,
+    uint256 reservesCount,
     address oracle
   ) external view {
     ValidateBorrowLocalVars memory vars;
@@ -154,6 +157,7 @@ library ValidationLogic {
       reservesData,
       userConfig,
       reserves,
+      reservesCount,
       oracle
     );
 
@@ -298,7 +302,8 @@ library ValidationLogic {
     address reserveAddress,
     mapping(address => ReserveLogic.ReserveData) storage reservesData,
     UserConfiguration.Map storage userConfig,
-    address[] calldata reserves,
+    mapping(uint256 => address) storage reserves,
+    uint256 reservesCount,
     address oracle
   ) external view {
     uint256 underlyingBalance = IERC20(reserve.aTokenAddress).balanceOf(msg.sender);
@@ -313,6 +318,7 @@ library ValidationLogic {
         reservesData,
         userConfig,
         reserves,
+        reservesCount,
         oracle
       ),
       Errors.DEPOSIT_ALREADY_IN_USE

contracts/misc/AaveProtocolTestHelpers.sol

@@ -20,7 +20,7 @@ contract AaveProtocolTestHelpers {
 
   function getAllReservesTokens() external view returns (TokenData[] memory) {
     ILendingPool pool = ILendingPool(ADDRESSES_PROVIDER.getLendingPool());
-    address[] memory reserves = pool.getReserves();
+    address[] memory reserves = pool.getReservesList();
     TokenData[] memory reservesTokens = new TokenData[](reserves.length);
     for (uint256 i = 0; i < reserves.length; i++) {
       reservesTokens[i] = TokenData({
@@ -35,7 +35,7 @@ contract AaveProtocolTestHelpers {
 
   function getAllATokens() external view returns (TokenData[] memory) {
     ILendingPool pool = ILendingPool(ADDRESSES_PROVIDER.getLendingPool());
-    address[] memory reserves = pool.getReserves();
+    address[] memory reserves = pool.getReservesList();
     TokenData[] memory aTokens = new TokenData[](reserves.length);
     for (uint256 i = 0; i < reserves.length; i++) {
       (address aTokenAddress, , ) = pool.getReserveTokensAddresses(reserves[i]);

contracts/misc/WalletBalanceProvider.sol

@@ -86,7 +86,7 @@ contract WalletBalanceProvider {
   {
     ILendingPool pool = ILendingPool(_provider.getLendingPool());
 
-    address[] memory reserves = pool.getReserves();
+    address[] memory reserves = pool.getReservesList();
 
     uint256[] memory balances = new uint256[](reserves.length);
 

deployed-contracts.json

@@ -608,7 +608,7 @@
       "deployer": "0xc783df8a850f42e7F7e57013759C285caa701eB6"
     },
     "localhost": {
-      "address": "0xEcb928A3c079a1696Aa5244779eEc3dE1717fACd",
+      "address": "0xa89E20284Bd638F31b0011D0fC754Fc9d2fa73e3",
       "deployer": "0xc783df8a850f42e7F7e57013759C285caa701eB6"
     },
     "coverage": {
@@ -636,7 +636,7 @@
       "deployer": "0xc783df8a850f42e7F7e57013759C285caa701eB6"
     },
     "localhost": {
-      "address": "0xDFbeeed692AA81E7f86E72F7ACbEA2A1C4d63544",
+      "address": "0xaA935993065F2dDB1d13623B1941C7AEE3A60F23",
       "deployer": "0xc783df8a850f42e7F7e57013759C285caa701eB6"
     },
     "coverage": {
@@ -650,7 +650,7 @@
       "deployer": "0xc783df8a850f42e7F7e57013759C285caa701eB6"
     },
     "localhost": {
-      "address": "0x5191aA68c7dB195181Dd2441dBE23A48EA24b040",
+      "address": "0x35A2624888e207e4B3434E9a9E250bF6Ee68FeA3",
       "deployer": "0xc783df8a850f42e7F7e57013759C285caa701eB6"
     },
     "coverage": {