feat: adjusted aggregator contract for price adjustments based on signed percentage

Author: dmytro-horbatenko

…AggregatorV3CompatibleFeedDiscounted.sol …omAggregatorV3CompatibleFeedAdjusted.solcontracts/feeds/CustomAggregatorV3CompatibleFeedDiscounted.sol renamed to contracts/feeds/CustomAggregatorV3CompatibleFeedAdjusted.sol contracts/feeds/CustomAggregatorV3CompatibleFeedDiscounted.sol renamed to contracts/feeds/CustomAggregatorV3CompatibleFeedAdjusted.sol

@@ -4,38 +4,44 @@ pragma solidity 0.8.9;
 import "@chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol";
 
 /**
- * @title CustomAggregatorV3CompatibleFeedDiscounted
- * @notice AggregatorV3 compatible proxy-feed that discounts the price
- * of an underlying chainlink compatible feed by a given percentage
+ * @title CustomAggregatorV3CompatibleFeedAdjusted
+ * @notice AggregatorV3 compatible proxy-feed that adjusts the price
+ * of an underlying chainlink compatible feed by a given signed percentage.
+ * Positive adjustmentPercentage lowers the reported price.
+ * Negative adjustmentPercentage raises the reported price.
  * @author RedDuck Software
  */
-contract CustomAggregatorV3CompatibleFeedDiscounted is AggregatorV3Interface {
+contract CustomAggregatorV3CompatibleFeedAdjusted is AggregatorV3Interface {
     /**
      * @notice the underlying chainlink compatible feed
      */
     AggregatorV3Interface public immutable underlyingFeed;
 
     /**
-     * @notice the discount percentage. Expressed in 10 ** decimals() precision
-     * Example: 10 ** decimals() = 1%
+     * @notice the adjustment percentage (signed).
+     * Expressed in 10 ** decimals() precision.
+     * Example: 10 ** decimals() = 1%, -(10 ** decimals()) = -1%
+     * Positive values lower the reported price.
+     * Negative values raise the reported price.
      */
-    uint256 public immutable discountPercentage;
+    int256 public immutable adjustmentPercentage;
 
     /**
      * @notice constructor
      * @param _underlyingFeed the underlying chainlink compatible feed
-     * @param _discountPercentage the discount percentage. Expressed in 10 ** decimals() precision
+     * @param _adjustmentPercentage signed adjustment percentage in 10 ** decimals() precision
      */
-    constructor(address _underlyingFeed, uint256 _discountPercentage) {
-        require(_underlyingFeed != address(0), "CAD: !underlying feed");
+    constructor(address _underlyingFeed, int256 _adjustmentPercentage) {
+        require(_underlyingFeed != address(0), "CAA: !underlying feed");
         underlyingFeed = AggregatorV3Interface(_underlyingFeed);
 
+        int256 maxPct = int256(100 * (10**decimals()));
         require(
-            _discountPercentage <= 100 * (10**decimals()),
-            "CAD: !discount percentage"
+            _adjustmentPercentage >= -maxPct && _adjustmentPercentage <= maxPct,
+            "CAA: invalid adjustment"
         );
 
-        discountPercentage = _discountPercentage;
+        adjustmentPercentage = _adjustmentPercentage;
     }
 
     /**
@@ -60,7 +66,7 @@ contract CustomAggregatorV3CompatibleFeedDiscounted is AggregatorV3Interface {
             answeredInRound
         ) = underlyingFeed.latestRoundData();
 
-        answer = _calculateDiscountedAnswer(answer);
+        answer = _calculateAdjustedAnswer(answer);
     }
 
     /**
@@ -91,7 +97,7 @@ contract CustomAggregatorV3CompatibleFeedDiscounted is AggregatorV3Interface {
             updatedAt,
             answeredInRound
         ) = underlyingFeed.getRoundData(_roundId);
-        answer = _calculateDiscountedAnswer(answer);
+        answer = _calculateAdjustedAnswer(answer);
     }
 
     /**
@@ -105,27 +111,28 @@ contract CustomAggregatorV3CompatibleFeedDiscounted is AggregatorV3Interface {
      * @inheritdoc AggregatorV3Interface
      */
     function description() public view returns (string memory) {
-        return
-            string(
-                abi.encodePacked(underlyingFeed.description(), " Discounted")
-            );
+        if (adjustmentPercentage == 0) return underlyingFeed.description();
+        string memory suffix = adjustmentPercentage > 0
+            ? " PriceLowered"
+            : " PriceRaised";
+        return string(abi.encodePacked(underlyingFeed.description(), suffix));
     }
 
     /**
-     * @dev calculates the discounted answer
-     * @param _answer the answer to discount
-     * @return the discounted answer
+     * @dev calculates the adjusted answer
+     * @param _answer the answer to adjust
+     * @return the adjusted answer
      */
-    function _calculateDiscountedAnswer(int256 _answer)
+    function _calculateAdjustedAnswer(int256 _answer)
         internal
         view
         returns (int256)
     {
-        require(_answer >= 0, "CAD: !_answer");
+        require(_answer >= 0, "CAA: !_answer");
 
-        int256 discount = (_answer * int256(discountPercentage)) /
+        int256 adjustment = (_answer * adjustmentPercentage) /
             int256(100 * 10**decimals());
 
-        return _answer - discount;
+        return _answer - adjustment;
     }
 }

contracts/testers/CustomAggregatorV3CompatibleFeedAdjustedTester.sol

@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.9;
+
+import "../feeds/CustomAggregatorV3CompatibleFeedAdjusted.sol";
+
+contract CustomAggregatorV3CompatibleFeedAdjustedTester is
+    CustomAggregatorV3CompatibleFeedAdjusted
+{
+    constructor(address _underlyingFeed, int256 _adjustmentPercentage)
+        CustomAggregatorV3CompatibleFeedAdjusted(
+            _underlyingFeed,
+            _adjustmentPercentage
+        )
+    {}
+
+    function getAdjustedAnswer(int256 _answer) public view returns (int256) {
+        return _calculateAdjustedAnswer(_answer);
+    }
+}

contracts/testers/CustomAggregatorV3CompatibleFeedDiscountedTester.sol

@@ -26,7 +26,7 @@ export type TokenContractNames = {
 type CommonContractNames = Omit<TokenContractNames, 'token'> & {
   ac: string;
   customAggregator: string;
-  customAggregatorDiscounted: string;
+  customAggregatorAdjusted: string;
   layerZero: {
     oftAdapter: string;
     vaultComposer: string;
@@ -149,7 +149,7 @@ export const getCommonContractNames = (): CommonContractNames => {
     dataFeed: 'DataFeed',
     customAggregator: 'CustomAggregatorV3CompatibleFeed',
     customAggregatorGrowth: 'CustomAggregatorV3CompatibleFeedGrowth',
-    customAggregatorDiscounted: 'CustomAggregatorV3CompatibleFeedDiscounted',
+    customAggregatorAdjusted: 'CustomAggregatorV3CompatibleFeedAdjusted',
     roles: 'MidasAccessControlRoles',
     dataFeedComposite: 'CompositeDataFeed',
     dataFeedMultiply: 'CompositeDataFeedMultiply',

helpers/contracts.ts

@@ -72,8 +72,8 @@ export type DeployCustomAggregatorRegularConfig =
     type?: 'REGULAR';
   };
 
-export type DeployCustomAggregatorDiscountedConfig = {
-  discountPercentage: BigNumberish;
+export type DeployCustomAggregatorAdjustedConfig = {
+  adjustmentPercentage: BigNumberish;
   underlyingFeed: `0x${string}` | 'customFeed';
 };
 
@@ -410,14 +410,14 @@ export const deployMTokenDataFeed = async (
   );
 };
 
-export const deployMTokenCustomAggregatorDiscounted = async (
+export const deployMTokenCustomAggregatorAdjusted = async (
   hre: HardhatRuntimeEnvironment,
   token: MTokenName,
 ) => {
-  await deployCustomAggregatorDiscounted(
+  await deployCustomAggregatorAdjusted(
     hre,
     token,
-    getDeploymentGenericConfig(hre, token, 'customAggregatorDiscounted'),
+    getDeploymentGenericConfig(hre, token, 'customAggregatorAdjusted'),
   );
 };
 
@@ -536,10 +536,10 @@ const deployCustomAggregator = async (
   );
 };
 
-const deployCustomAggregatorDiscounted = async (
+const deployCustomAggregatorAdjusted = async (
   hre: HardhatRuntimeEnvironment,
   token: MTokenName,
-  networkConfig?: DeployCustomAggregatorDiscountedConfig,
+  networkConfig?: DeployCustomAggregatorAdjustedConfig,
 ) => {
   const addresses = getCurrentAddresses(hre);
 
@@ -558,7 +558,7 @@ const deployCustomAggregatorDiscounted = async (
 
   await deployAndVerify(
     hre,
-    getCommonContractNames().customAggregatorDiscounted,
-    [underlyingFeed, networkConfig.discountPercentage],
+    getCommonContractNames().customAggregatorAdjusted,
+    [underlyingFeed, networkConfig.adjustmentPercentage],
   );
 };

scripts/deploy/common/data-feed.ts

@@ -3,8 +3,8 @@ import { HardhatRuntimeEnvironment } from 'hardhat/types';
 
 import { AddFeeWaivedConfig, AddPaymentTokensConfig } from './common-vault';
 import {
+  DeployCustomAggregatorAdjustedConfig,
   DeployCustomAggregatorConfig,
-  DeployCustomAggregatorDiscountedConfig,
   DeployDataFeedConfig,
   SetRoundDataConfig,
 } from './data-feed';
@@ -94,7 +94,7 @@ export type PostDeployConfig = {
 export type DeploymentConfig = {
   genericConfigs: {
     customAggregator?: DeployCustomAggregatorConfig;
-    customAggregatorDiscounted?: DeployCustomAggregatorDiscountedConfig;
+    customAggregatorAdjusted?: DeployCustomAggregatorAdjustedConfig;
     dataFeed?: DeployDataFeedConfig;
   };
   networkConfigs: Record<

scripts/deploy/common/types.ts

@@ -1,12 +1,12 @@
 import { HardhatRuntimeEnvironment } from 'hardhat/types';
 
 import { getMTokenOrThrow } from '../../../helpers/utils';
-import { deployMTokenCustomAggregatorDiscounted } from '../common/data-feed';
+import { deployMTokenCustomAggregatorAdjusted } from '../common/data-feed';
 import { DeployFunction } from '../common/types';
 
 const func: DeployFunction = async (hre: HardhatRuntimeEnvironment) => {
   const mToken = getMTokenOrThrow(hre);
-  await deployMTokenCustomAggregatorDiscounted(hre, mToken);
+  await deployMTokenCustomAggregatorAdjusted(hre, mToken);
 };
 
 export default func;

…isc/deploy_CustomAggregatorDiscounted.ts …/misc/deploy_CustomAggregatorAdjusted.tsscripts/deploy/misc/deploy_CustomAggregatorDiscounted.ts renamed to scripts/deploy/misc/deploy_CustomAggregatorAdjusted.ts scripts/deploy/misc/deploy_CustomAggregatorDiscounted.ts renamed to scripts/deploy/misc/deploy_CustomAggregatorAdjusted.ts

@@ -43,7 +43,7 @@ import {
   RedemptionVaultWithMTokenTest__factory,
   AaveV3PoolMock__factory,
   MorphoVaultMock__factory,
-  CustomAggregatorV3CompatibleFeedDiscountedTester__factory,
+  CustomAggregatorV3CompatibleFeedAdjustedTester__factory,
   DepositVaultWithAaveTest__factory,
   DepositVaultWithMorphoTest__factory,
   DepositVaultWithMTokenTest__factory,
@@ -714,8 +714,8 @@ export const defaultDeploy = async () => {
     parseUnits('10000', mockedAggregatorDecimals),
   );
 
-  const customFeedDiscounted =
-    await new CustomAggregatorV3CompatibleFeedDiscountedTester__factory(
+  const customFeedAdjusted =
+    await new CustomAggregatorV3CompatibleFeedAdjustedTester__factory(
       owner,
     ).deploy(customFeed.address, parseUnits('10', 8));
 
@@ -820,7 +820,7 @@ export const defaultDeploy = async () => {
 
   return {
     customFeed,
-    customFeedDiscounted,
+    customFeedAdjusted,
     customFeedGrowth,
     mTBILL,
     mBASIS,