feat: add governance pool setter

cspell.json

@@ -140,6 +140,7 @@
     "twap",
     "typechain",
     "TYPEHASH",
+    "Twocrypto",
     "Ubiqui",
     "UbiquiStick",
     "Unassigns",

packages/contracts/src/dollar/facets/UbiquityPoolFacet.sol

@@ -86,6 +86,11 @@ contract UbiquityPoolFacet is IUbiquityPool, Modifiers {
             );
     }
 
+    /// @inheritdoc IUbiquityPool
+    function governanceEthPoolAddress() external view returns (address) {
+        return LibUbiquityPool.governanceEthPoolAddress();
+    }
+
     //====================
     // Public functions
     //====================
@@ -199,6 +204,15 @@ contract UbiquityPoolFacet is IUbiquityPool, Modifiers {
         LibUbiquityPool.setFees(collateralIndex, newMintFee, newRedeemFee);
     }
 
+    /// @inheritdoc IUbiquityPool
+    function setGovernanceEthPoolAddress(
+        address newGovernanceEthPoolAddress
+    ) external onlyAdmin {
+        LibUbiquityPool.setGovernanceEthPoolAddress(
+            newGovernanceEthPoolAddress
+        );
+    }
+
     /// @inheritdoc IUbiquityPool
     function setPoolCeiling(
         uint256 collateralIndex,

packages/contracts/src/dollar/interfaces/ICurveTwocryptoOptimized.sol

@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.19;
+
+import {ICurveStableSwapMetaNG} from "./ICurveStableSwapMetaNG.sol";
+
+/**
+ * @notice Curve's CurveTwocryptoOptimized interface
+ *
+ * @dev Differences between Curve's crypto and stable swap meta pools (and how Ubiquity organization uses them):
+ * 1. They contain different tokens:
+ * a) Curve's stable swap metapool containts Dollar/3CRVLP pair
+ * b) Curve's crypto pool contains Governance/ETH pair
+ * 2. They use different bonding curve shapes:
+ * a) Curve's stable swap metapool is more straight (because underlying tokens are pegged to USD)
+ * b) Curve's crypto pool resembles Uniswap's bonding curve (because underlying tokens are not USD pegged)
+ *
+ * @dev Basically `ICurveTwocryptoOptimized` has the same interface as `ICurveStableSwapMetaNG`
+ * but we distinguish them in the code for clarity.
+ */
+interface ICurveTwocryptoOptimized is ICurveStableSwapMetaNG {}

packages/contracts/src/dollar/interfaces/IUbiquityPool.sol

@@ -84,6 +84,12 @@ interface IUbiquityPool {
         uint256 collateralIndex
     ) external view returns (uint256);
 
+    /**
+     * @notice Returns pool address for Governance/ETH pair
+     * @return Pool address
+     */
+    function governanceEthPoolAddress() external view returns (address);
+
     //====================
     // Public functions
     //====================
@@ -220,6 +226,21 @@ interface IUbiquityPool {
         uint256 newRedeemFee
     ) external;
 
+    /**
+     * @notice Sets a new pool address for Governance/ETH pair
+     *
+     * @dev Based on Curve's CurveTwocryptoOptimized contract. Used for fetching Governance token USD price.
+     * How it works:
+     * 1. Fetch Governance/ETH price from CurveTwocryptoOptimized's built-in oracle
+     * 2. Fetch ETH/USD price from chainlink feed
+     * 3. Calculate Governance token price in USD
+     *
+     * @param newGovernanceEthPoolAddress New pool address for Governance/ETH pair
+     */
+    function setGovernanceEthPoolAddress(
+        address newGovernanceEthPoolAddress
+    ) external;
+
     /**
      * @notice Sets max amount of collateral for a particular collateral token
      * @param collateralIndex Collateral token index

packages/contracts/src/dollar/libraries/LibUbiquityPool.sol

@@ -89,6 +89,11 @@ library LibUbiquityPool {
         bool[] isMintPaused;
         // whether redeeming is paused for a particular collateral index
         bool[] isRedeemPaused;
+        //====================================
+        // Governance token pricing related
+        //====================================
+        // Curve's CurveTwocryptoOptimized contract for Governance/ETH pair
+        address governanceEthPoolAddress;
     }
 
     /// @notice Struct used for detailed collateral information
@@ -150,6 +155,8 @@ library LibUbiquityPool {
         uint256 newMintFee,
         uint256 newRedeemFee
     );
+    /// @notice Emitted on setting a pool for Governance/ETH pair
+    event GovernanceEthPoolSet(address newGovernanceEthPoolAddress);
     /// @notice Emitted on toggling pause for mint/redeem/borrow
     event MintRedeemBorrowToggled(uint256 collateralIndex, uint8 toggleIndex);
     /// @notice Emitted when new pool ceiling (i.e. max amount of collateral) is set
@@ -360,6 +367,15 @@ library LibUbiquityPool {
             poolStorage.redeemCollateralBalances[userAddress][collateralIndex];
     }
 
+    /**
+     * @notice Returns pool address for Governance/ETH pair
+     * @return Pool address
+     */
+    function governanceEthPoolAddress() internal view returns (address) {
+        UbiquityPoolStorage storage poolStorage = ubiquityPoolStorage();
+        return poolStorage.governanceEthPoolAddress;
+    }
+
     //====================
     // Public functions
     //====================
@@ -832,6 +848,27 @@ library LibUbiquityPool {
         emit FeesSet(collateralIndex, newMintFee, newRedeemFee);
     }
 
+    /**
+     * @notice Sets a new pool address for Governance/ETH pair
+     *
+     * @dev Based on Curve's CurveTwocryptoOptimized contract. Used for fetching Governance token USD price.
+     * How it works:
+     * 1. Fetch Governance/ETH price from CurveTwocryptoOptimized's built-in oracle
+     * 2. Fetch ETH/USD price from chainlink feed
+     * 3. Calculate Governance token price in USD
+     *
+     * @param newGovernanceEthPoolAddress New pool address for Governance/ETH pair
+     */
+    function setGovernanceEthPoolAddress(
+        address newGovernanceEthPoolAddress
+    ) internal {
+        UbiquityPoolStorage storage poolStorage = ubiquityPoolStorage();
+
+        poolStorage.governanceEthPoolAddress = newGovernanceEthPoolAddress;
+
+        emit GovernanceEthPoolSet(newGovernanceEthPoolAddress);
+    }
+
     /**
      * @notice Sets max amount of collateral for a particular collateral token
      * @param collateralIndex Collateral token index

packages/contracts/src/dollar/mocks/MockCurveTwocryptoOptimized.sol

@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.19;
+
+import {ICurveTwocryptoOptimized} from "../interfaces/ICurveTwocryptoOptimized.sol";
+import {MockCurveStableSwapMetaNG} from "./MockCurveStableSwapMetaNG.sol";
+
+contract MockCurveTwocryptoOptimized is
+    ICurveTwocryptoOptimized,
+    MockCurveStableSwapMetaNG
+{
+    constructor(
+        address _token0,
+        address _token1
+    ) MockCurveStableSwapMetaNG(_token0, _token1) {}
+}

packages/contracts/test/diamond/facets/UbiquityPoolFacet.t.sol

@@ -8,6 +8,7 @@ import {LibUbiquityPool} from "../../../src/dollar/libraries/LibUbiquityPool.sol
 import {MockChainLinkFeed} from "../../../src/dollar/mocks/MockChainLinkFeed.sol";
 import {MockERC20} from "../../../src/dollar/mocks/MockERC20.sol";
 import {MockCurveStableSwapMetaNG} from "../../../src/dollar/mocks/MockCurveStableSwapMetaNG.sol";
+import {MockCurveTwocryptoOptimized} from "../../../src/dollar/mocks/MockCurveTwocryptoOptimized.sol";
 
 contract MockDollarAmoMinter is IDollarAmoMinter {
     function collateralDollarBalance() external pure returns (uint256) {
@@ -24,7 +25,9 @@ contract UbiquityPoolFacetTest is DiamondTestSetup {
     MockERC20 collateralToken;
     MockChainLinkFeed collateralTokenPriceFeed;
     MockCurveStableSwapMetaNG curveDollarMetaPool;
+    MockCurveTwocryptoOptimized curveGovernanceEthPool;
     MockERC20 curveTriPoolLpToken;
+    MockERC20 wethToken;
 
     address user = address(1);
 
@@ -44,6 +47,7 @@ contract UbiquityPoolFacetTest is DiamondTestSetup {
         uint256 newMintFee,
         uint256 newRedeemFee
     );
+    event GovernanceEthPoolSet(address newGovernanceEthPoolAddress);
     event MintRedeemBorrowToggled(uint256 collateralIndex, uint8 toggleIndex);
     event PoolCeilingSet(uint256 collateralIndex, uint256 newCeiling);
     event PriceThresholdsSet(
@@ -63,6 +67,9 @@ contract UbiquityPoolFacetTest is DiamondTestSetup {
         // init collateral price feed
         collateralTokenPriceFeed = new MockChainLinkFeed();
 
+        // init WETH token
+        wethToken = new MockERC20("WETH", "WETH", 18);
+
         // init Curve 3CRV-LP token
         curveTriPoolLpToken = new MockERC20("3CRV", "3CRV", 18);
 
@@ -72,6 +79,12 @@ contract UbiquityPoolFacetTest is DiamondTestSetup {
             address(curveTriPoolLpToken)
         );
 
+        // init Curve Governance-WETH crypto pool
+        curveGovernanceEthPool = new MockCurveTwocryptoOptimized(
+            address(governanceToken),
+            address(wethToken)
+        );
+
         // add collateral token to the pool
         uint256 poolCeiling = 50_000e18; // max 50_000 of collateral tokens is allowed
         ubiquityPoolFacet.addCollateralToken(
@@ -96,9 +109,6 @@ contract UbiquityPoolFacetTest is DiamondTestSetup {
             1 days // price feed staleness threshold in seconds
         );
 
-        // set collateral ratio to 100%
-        ubiquityPoolFacet.setCollateralRatio(1_000_000);
-
         // enable collateral at index 0
         ubiquityPoolFacet.toggleCollateral(0);
         // set mint and redeem fees
@@ -111,6 +121,12 @@ contract UbiquityPoolFacetTest is DiamondTestSetup {
         ubiquityPoolFacet.setRedemptionDelayBlocks(2);
         // set mint price threshold to $1.01 and redeem price to $0.99
         ubiquityPoolFacet.setPriceThresholds(1010000, 990000);
+        // set collateral ratio to 100%
+        ubiquityPoolFacet.setCollateralRatio(1_000_000);
+        // set Governance-ETH pool
+        ubiquityPoolFacet.setGovernanceEthPoolAddress(
+            address(curveGovernanceEthPool)
+        );
 
         // init AMO minter
         dollarAmoMinter = new MockDollarAmoMinter();
@@ -303,6 +319,14 @@ contract UbiquityPoolFacetTest is DiamondTestSetup {
         assertEq(redeemCollateralBalance, 97.02e18);
     }
 
+    function testGovernanceEthPoolAddress_ShouldReturnGovernanceEthPoolAddress()
+        public
+    {
+        address governanceEthPoolAddress = ubiquityPoolFacet
+            .governanceEthPoolAddress();
+        assertEq(governanceEthPoolAddress, address(curveGovernanceEthPool));
+    }
+
     //====================
     // Public functions
     //====================
@@ -918,6 +942,30 @@ contract UbiquityPoolFacetTest is DiamondTestSetup {
         vm.stopPrank();
     }
 
+    function testSetGovernanceEthPoolAddress_ShouldSetGovernanceEthPoolAddress()
+        public
+    {
+        vm.startPrank(admin);
+
+        address oldGovernanceEthPoolAddress = ubiquityPoolFacet
+            .governanceEthPoolAddress();
+        assertEq(oldGovernanceEthPoolAddress, address(curveGovernanceEthPool));
+
+        address newGovernanceEthPoolAddress = address(1);
+        vm.expectEmit(address(ubiquityPoolFacet));
+        emit GovernanceEthPoolSet(newGovernanceEthPoolAddress);
+        ubiquityPoolFacet.setGovernanceEthPoolAddress(
+            newGovernanceEthPoolAddress
+        );
+
+        assertEq(
+            ubiquityPoolFacet.governanceEthPoolAddress(),
+            newGovernanceEthPoolAddress
+        );
+
+        vm.stopPrank();
+    }
+
     function testSetPoolCeiling_ShouldSetMaxAmountOfTokensAllowedForCollateral()
         public
     {