feat: add special case price oracle for weETH

Author: rhlsthrm

contracts/oracles/default/RedstoneAdapterPriceOracleWeETH.sol

@@ -0,0 +1,69 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity >=0.8.0;
+
+import "openzeppelin-contracts-upgradeable/contracts/token/ERC20/ERC20Upgradeable.sol";
+
+import "../../external/redstone/IRedstoneOracle.sol";
+import "../BasePriceOracle.sol";
+
+/**
+ * @title RedstoneAdapterPriceOracle
+ * @notice Returns prices from Redstone.
+ * @dev Implements `BasePriceOracle`.
+ * @author Veliko Minkov <[email protected]> (https://github.com/vminkov)
+ */
+contract RedstoneAdapterPriceOracleWeETH is BasePriceOracle {
+  /**
+   * @notice The Redstone oracle contract
+   */
+  IRedstoneOracle public REDSTONE_ORACLE;
+
+  /**
+   * @dev Constructor to set admin, wtoken address and native token USD price feed address
+   * @param redstoneOracle The Redstone oracle contract address
+   */
+  constructor(address redstoneOracle) {
+    REDSTONE_ORACLE = IRedstoneOracle(redstoneOracle);
+  }
+
+  /**
+   * @notice Internal function returning the price in of `underlying`.
+   * @dev will return a price denominated in the native token
+   */
+  function _price(address underlying) internal view returns (uint256) {
+    // special case for wrsETH
+    // if input is wrsETH, we need to get the price of rsETH
+    if (underlying == 0x04C0599Ae5A44757c0af6F9eC3b93da8976c150A) {
+      underlying = 0x028227c4dd1e5419d11Bb6fa6e661920c519D4F5;
+    }
+    uint256 priceInUsd = REDSTONE_ORACLE.priceOf(underlying);
+    uint256 priceOfNativeInUsd = REDSTONE_ORACLE.priceOfETH();
+    return (priceInUsd * 1e18) / priceOfNativeInUsd;
+  }
+
+  /**
+   * @notice Returns the price in of `underlying` either in the
+   * native token (implements `BasePriceOracle`).
+   */
+  function price(address underlying) external view override returns (uint256) {
+    return _price(underlying);
+  }
+
+  /**
+   * @notice Returns the price in WNATIVE of the token underlying `cToken`.
+   * @dev Implements the `BasePriceOracle` interface for Ionic pools (and Compound v2).
+   * @return Price in WNATIVE of the token underlying `cToken`, scaled by `10 ** (36 - underlyingDecimals)`.
+   */
+  function getUnderlyingPrice(ICErc20 cToken) external view override returns (uint256) {
+    // Get underlying token address
+    address underlying = cToken.underlying();
+
+    uint256 oraclePrice = _price(underlying);
+
+    uint256 underlyingDecimals = uint256(ERC20Upgradeable(underlying).decimals());
+    return
+      underlyingDecimals <= 18
+        ? uint256(oraclePrice) * (10 ** (18 - underlyingDecimals))
+        : uint256(oraclePrice) / (10 ** (underlyingDecimals - 18));
+  }
+}

contracts/test/DevTesting.t.sol

@@ -13,6 +13,7 @@ import { ICErc20 } from "../compound/CTokenInterfaces.sol";
 import { ISwapRouter } from "../external/uniswap/ISwapRouter.sol";
 import { RedstoneAdapterPriceOracle } from "../oracles/default/RedstoneAdapterPriceOracle.sol";
 import { RedstoneAdapterPriceOracleWrsETH } from "../oracles/default/RedstoneAdapterPriceOracleWrsETH.sol";
+import { RedstoneAdapterPriceOracleWeETH } from "../oracles/default/RedstoneAdapterPriceOracleWeETH.sol";
 import { MasterPriceOracle, BasePriceOracle } from "../oracles/MasterPriceOracle.sol";
 import { PoolLens } from "../PoolLens.sol";
 import { PoolLensSecondary } from "../PoolLensSecondary.sol";
@@ -427,6 +428,23 @@ contract DevTesting is BaseTest {
     emit log_named_uint("price of wrsEth", price);
   }
 
+  function testModeWeETH() public debuggingOnly forkAtBlock(MODE_MAINNET, 6861468) {
+    address weEth = 0x04C0599Ae5A44757c0af6F9eC3b93da8976c150A;
+    RedstoneAdapterPriceOracleWeETH oracle = new RedstoneAdapterPriceOracleWeETH(
+      0x7C1DAAE7BB0688C9bfE3A918A4224041c7177256
+    );
+    MasterPriceOracle mpo = MasterPriceOracle(ap.getAddress("MasterPriceOracle"));
+
+    BasePriceOracle[] memory oracles = new BasePriceOracle[](1);
+    oracles[0] = oracle;
+    vm.prank(multisig);
+    mpo.add(asArray(weEth), oracles);
+
+    uint256 price = mpo.price(weEth);
+    emit log_named_uint("price of weEth", price);
+    assertEq(price, 1036212437077011599);
+  }
+
   function _functionCall(
     address target,
     bytes memory data,