Merge pull request #591 from aave/feat/add-getReserveId

Added getReserveAddressById

Author: The-3D

contracts/interfaces/IPool.sol

@@ -602,12 +602,19 @@ interface IPool {
   ) external;
 
   /**
-   * @notice Returns the list of the initialized reserves
+   * @notice Returns the list of the underlying assets of all the initialized reserves
    * @dev It does not include dropped reserves
-   * @return The addresses of the reserves
+   * @return The addresses of the underlying assets of the initialized reserves
    **/
   function getReservesList() external view returns (address[] memory);
 
+  /**
+   * @notice Returns the address of the underlying asset of a reserve by the reserve id as stored in the DataTypes.ReserveData struct
+   * @param id The id of the reserve as stored in the DataTypes.ReserveData struct
+   * @return The address of the reserve associated with id
+   **/
+  function getReserveAddressById(uint16 id) external view returns (address);
+
   /**
    * @notice Returns the PoolAddressesProvider connected to this contract
    * @return The address of the PoolAddressesProvider

contracts/protocol/pool/Pool.sol

@@ -553,6 +553,11 @@ contract Pool is VersionedInitializable, PoolStorage, IPool {
     return reservesList;
   }
 
+  /// @inheritdoc IPool
+  function getReserveAddressById(uint16 id) external view returns (address) {
+    return _reservesList[id];
+  }
+
   /// @inheritdoc IPool
   function MAX_STABLE_RATE_BORROW_SIZE_PERCENT() public view virtual override returns (uint256) {
     return _maxStableRateBorrowSizePercent;

test-suites/pool-get-reserve-address-by-id.spec.ts

@@ -0,0 +1,35 @@
+import { expect } from 'chai';
+import { makeSuite, TestEnv } from './helpers/make-suite';
+import { evmSnapshot, evmRevert, ZERO_ADDRESS } from '@aave/deploy-v3';
+
+makeSuite('Pool: getReservesList', (testEnv: TestEnv) => {
+  let snap: string;
+
+  beforeEach(async () => {
+    snap = await evmSnapshot();
+  });
+
+  afterEach(async () => {
+    await evmRevert(snap);
+  });
+
+  it('User gets address of reserve by id', async () => {
+    const { pool, usdc } = testEnv;
+
+    const reserveData = await pool.getReserveData(usdc.address);
+
+    const reserveAddress = await pool.getReserveAddressById(reserveData.id);
+
+    await expect(reserveAddress).to.be.eq(usdc.address);
+  });
+
+  it('User calls `getReservesList` with a wrong id (id > reservesCount)', async () => {
+    const { pool } = testEnv;
+
+    // MAX_NUMBER_RESERVES is always greater than reservesCount
+    const maxNumberOfReserves = await pool.MAX_NUMBER_RESERVES();
+    const reserveAddress = await pool.getReserveAddressById(maxNumberOfReserves +1);
+
+    await expect(reserveAddress).to.be.eq(ZERO_ADDRESS);
+  });
+});