feat: add support for pendle's getPtToSyRate

contracts/interfaces/IPendlePtOracle.sol

@@ -3,6 +3,9 @@ pragma solidity 0.8.25;
 
 interface IPendlePtOracle {
     function getPtToAssetRate(address market, uint32 duration) external view returns (uint256);
+
+    function getPtToSyRate(address market, uint32 duration) external view returns (uint256);
+
     function getOracleState(
         address market,
         uint32 duration

contracts/oracles/PendleOracle.sol

@@ -11,10 +11,28 @@ import { ensureNonzeroAddress, ensureNonzeroValue } from "@venusprotocol/solidit
  * @notice This oracle fetches the price of a pendle token
  */
 contract PendleOracle is CorrelatedTokenOracle {
+    /// @notice Which asset to use as a base for the returned PT
+    /// price. Can be either a standardized yield token (SY), in
+    /// this case PT/SY price is returned, or the underlying
+    /// asset directly. Note that using PT_TO_ASSET rate assumes
+    /// that the yield token can be seamlessly redeemed for the
+    /// underlying asset. In reality, this might not always be
+    /// the case. For more details, see
+    /// https://docs.pendle.finance/Developers/Contracts/StandardizedYield
+    enum RateKind {
+        PT_TO_ASSET,
+        PT_TO_SY
+    }
+
     /// @notice Address of the PT oracle
     /// @custom:oz-upgrades-unsafe-allow state-variable-immutable
     IPendlePtOracle public immutable PT_ORACLE;
 
+    /// @notice Whether to use PT/SY (standardized yield token) rate
+    /// or PT/underlying asset rate
+    /// @custom:oz-upgrades-unsafe-allow state-variable-immutable
+    RateKind public immutable RATE_KIND;
+
     /// @notice Address of the market
     /// @custom:oz-upgrades-unsafe-allow state-variable-immutable
     address public immutable MARKET;
@@ -31,6 +49,7 @@ contract PendleOracle is CorrelatedTokenOracle {
     constructor(
         address market,
         address ptOracle,
+        RateKind rateKind,
         address ptToken,
         address underlyingToken,
         address resilientOracle,
@@ -42,6 +61,7 @@ contract PendleOracle is CorrelatedTokenOracle {
 
         MARKET = market;
         PT_ORACLE = IPendlePtOracle(ptOracle);
+        RATE_KIND = rateKind;
         TWAP_DURATION = twapDuration;
 
         (bool increaseCardinalityRequired, , bool oldestObservationSatisfied) = PT_ORACLE.getOracleState(
@@ -54,10 +74,13 @@ contract PendleOracle is CorrelatedTokenOracle {
     }
 
     /**
-     * @notice Fetches the amount of underlying token for 1 pendle token
-     * @return amount The amount of underlying token for pendle token
+     * @notice Fetches the amount of underlying or SY token for 1 pendle token
+     * @return amount The amount of underlying or SY token for pendle token
      */
     function _getUnderlyingAmount() internal view override returns (uint256) {
+        if (RATE_KIND == RateKind.PT_TO_SY) {
+            return PT_ORACLE.getPtToSyRate(MARKET, TWAP_DURATION);
+        }
         return PT_ORACLE.getPtToAssetRate(MARKET, TWAP_DURATION);
     }
 }

contracts/oracles/mocks/MockPendlePtOracle.sol

@@ -6,23 +6,32 @@ import "@openzeppelin/contracts/access/Ownable.sol";
 
 contract MockPendlePtOracle is IPendlePtOracle, Ownable {
     mapping(address => mapping(uint32 => uint256)) public ptToAssetRate;
+    mapping(address => mapping(uint32 => uint256)) public ptToSyRate;
 
     constructor() Ownable() {}
 
     function setPtToAssetRate(address market, uint32 duration, uint256 rate) external onlyOwner {
         ptToAssetRate[market][duration] = rate;
     }
 
+    function setPtToSyRate(address market, uint32 duration, uint256 rate) external onlyOwner {
+        ptToSyRate[market][duration] = rate;
+    }
+
     function getPtToAssetRate(address market, uint32 duration) external view returns (uint256) {
         return ptToAssetRate[market][duration];
     }
 
+    function getPtToSyRate(address market, uint32 duration) external view returns (uint256) {
+        return ptToSyRate[market][duration];
+    }
+
     function getOracleState(
-        address market,
-        uint32 duration
+        address /* market */,
+        uint32 /* duration */
     )
         external
-        view
+        pure
         returns (bool increaseCardinalityRequired, uint16 cardinalityRequired, bool oldestObservationSatisfied)
     {
         return (false, 0, true);

deploy/7-deploy-pendle-oracle.ts

@@ -4,6 +4,11 @@ import { HardhatRuntimeEnvironment } from "hardhat/types";
 
 import { ADDRESSES } from "../helpers/deploymentConfig";
 
+enum PendleRateKind {
+  PT_TO_ASSET = 0,
+  PT_TO_SY = 1,
+}
+
 const func: DeployFunction = async ({
   getNamedAccounts,
   deployments,
@@ -32,6 +37,7 @@ const func: DeployFunction = async ({
     args: [
       PTweETH_26DEC2024_Market || "0x0000000000000000000000000000000000000001",
       ptOracleAddress,
+      PendleRateKind.PT_TO_ASSET,
       PTweETH_26DEC2024,
       WETH,
       oracle.address,

test/PendleOracle.ts

@@ -1,27 +1,37 @@
-import { smock } from "@defi-wonderland/smock";
+import { FakeContract, smock } from "@defi-wonderland/smock";
 import chai from "chai";
 import { parseUnits } from "ethers/lib/utils";
 import { ethers } from "hardhat";
 
 import { ADDRESSES } from "../helpers/deploymentConfig";
-import { BEP20Harness, IPendlePtOracle, ResilientOracleInterface } from "../typechain-types";
+import {
+  BEP20Harness,
+  IPendlePtOracle,
+  PendleOracle__factory,
+  ResilientOracleInterface,
+} from "../typechain-types";
 import { addr0000 } from "./utils/data";
 
 const { expect } = chai;
 chai.use(smock.matchers);
 
 const { PTweETH_26DEC2024, PTweETH_26DEC2024_Market, PTOracle, eETH } = ADDRESSES.ethereum;
 const eETH_PRICE = parseUnits("3400", 18);
-const PRICE_DENOMINATOR = parseUnits("1", 18);
-const EETH_AMOUNT_FOR_ONE_WEETH = parseUnits("0.923601422168630818", 18);
+const PT_TO_ASSET_RATE = parseUnits("0.923601422168630818", 18);
+const PT_TO_SY_RATE = parseUnits("0.93", 18);
 const DURATION = 3600; // 1 hour
 
+enum PendleRateKind {
+  PT_TO_ASSET,
+  PT_TO_SY,
+}
+
 describe("PendleOracle unit tests", () => {
-  let ptWeETHMock;
-  let resilientOracleMock;
-  let pendleOracle;
-  let pendleOracleFactory;
-  let ptOracleMock;
+  let ptWeETHMock: FakeContract<BEP20Harness>;
+  let resilientOracleMock: FakeContract<ResilientOracleInterface>;
+  let pendleOracleFactory: PendleOracle__factory;
+  let ptOracleMock: FakeContract<IPendlePtOracle>;
+
   before(async () => {
     //  To initialize the provider we need to hit the node with any request
     await ethers.getSigners();
@@ -32,7 +42,8 @@ describe("PendleOracle unit tests", () => {
     ptWeETHMock.decimals.returns(18);
 
     ptOracleMock = await smock.fake<IPendlePtOracle>("IPendlePtOracle", { address: PTOracle });
-    ptOracleMock.getPtToAssetRate.returns(EETH_AMOUNT_FOR_ONE_WEETH);
+    ptOracleMock.getPtToAssetRate.returns(PT_TO_ASSET_RATE);
+    ptOracleMock.getPtToSyRate.returns(PT_TO_SY_RATE);
     ptOracleMock.getOracleState.returns([false, 0, true]);
 
     pendleOracleFactory = await ethers.getContractFactory("PendleOracle");
@@ -44,6 +55,7 @@ describe("PendleOracle unit tests", () => {
         pendleOracleFactory.deploy(
           addr0000,
           ptOracleMock.address,
+          PendleRateKind.PT_TO_ASSET,
           ptWeETHMock.address,
           eETH,
           resilientOracleMock.address,
@@ -56,6 +68,7 @@ describe("PendleOracle unit tests", () => {
         pendleOracleFactory.deploy(
           PTweETH_26DEC2024_Market,
           addr0000,
+          PendleRateKind.PT_TO_ASSET,
           ptWeETHMock.address,
           eETH,
           resilientOracleMock.address,
@@ -68,6 +81,7 @@ describe("PendleOracle unit tests", () => {
         pendleOracleFactory.deploy(
           PTweETH_26DEC2024_Market,
           ptOracleMock.address,
+          PendleRateKind.PT_TO_ASSET,
           addr0000,
           eETH,
           resilientOracleMock.address,
@@ -80,6 +94,7 @@ describe("PendleOracle unit tests", () => {
         pendleOracleFactory.deploy(
           PTweETH_26DEC2024_Market,
           ptOracleMock.address,
+          PendleRateKind.PT_TO_ASSET,
           ptWeETHMock.address,
           addr0000,
           resilientOracleMock.address,
@@ -92,6 +107,7 @@ describe("PendleOracle unit tests", () => {
         pendleOracleFactory.deploy(
           PTweETH_26DEC2024_Market,
           ptOracleMock.address,
+          PendleRateKind.PT_TO_ASSET,
           ptWeETHMock.address,
           eETH,
           addr0000,
@@ -104,6 +120,7 @@ describe("PendleOracle unit tests", () => {
         pendleOracleFactory.deploy(
           PTweETH_26DEC2024_Market,
           ptOracleMock.address,
+          PendleRateKind.PT_TO_ASSET,
           ptWeETHMock.address,
           eETH,
           resilientOracleMock.address,
@@ -119,6 +136,7 @@ describe("PendleOracle unit tests", () => {
         pendleOracleFactory.deploy(
           PTweETH_26DEC2024_Market,
           ptOracleMock.address,
+          PendleRateKind.PT_TO_ASSET,
           ptWeETHMock.address,
           eETH,
           resilientOracleMock.address,
@@ -128,26 +146,34 @@ describe("PendleOracle unit tests", () => {
 
       ptOracleMock.getOracleState.returns([false, 0, true]);
     });
+  });
 
-    it("should deploy contract", async () => {
-      pendleOracle = await pendleOracleFactory.deploy(
+  describe("getPrice", () => {
+    const deploy = (kind: PendleRateKind) => {
+      return pendleOracleFactory.deploy(
         PTweETH_26DEC2024_Market,
         ptOracleMock.address,
+        kind,
         ptWeETHMock.address,
         eETH,
         resilientOracleMock.address,
         DURATION,
       );
-    });
-  });
+    };
 
-  describe("getPrice", () => {
     it("revert if wstETH address is wrong", async () => {
+      const pendleOracle = await deploy(PendleRateKind.PT_TO_ASSET);
       await expect(pendleOracle.getPrice(addr0000)).to.be.revertedWithCustomError(pendleOracle, "InvalidTokenAddress");
     });
 
-    it("should get correct price", async () => {
+    it("should get correct price for PT_TO_ASSET rate kind", async () => {
+      const pendleOracle = await deploy(PendleRateKind.PT_TO_ASSET);
       expect(await pendleOracle.getPrice(ptWeETHMock.address)).to.equal(parseUnits("3140.2448353733447812", 18));
     });
+
+    it("should get correct price for PT_TO_SY rate kind", async () => {
+      const pendleOracle = await deploy(PendleRateKind.PT_TO_SY);
+      expect(await pendleOracle.getPrice(ptWeETHMock.address)).to.equal(parseUnits("3162.0", 18));
+    });
   });
 });