Merge pull request #168 from credbull/dev/audit-yield

LiquidStone to accrue yield until the requestRedeem period
credbull · Oct 30, 2024 · 968c1f3 · 968c1f3
2 parents d860230 + 0662e9b
commit 968c1f3
Show file tree

Hide file tree

Showing 4 changed files with 86 additions and 12 deletions.
diff --git a/packages/contracts/src/yield/LiquidContinuousMultiTokenVault.sol b/packages/contracts/src/yield/LiquidContinuousMultiTokenVault.sol
@@ -374,15 +374,17 @@ contract LiquidContinuousMultiTokenVault is
         _yieldStrategy = yieldStrategy;
     }
 
-    /// @dev yield based on the associated yieldStrategy
-    function calcYield(uint256 principal, uint256 fromPeriod, uint256 toPeriod) public view returns (uint256 yield) {
-        // no yield earned when depositing and requesting redeem within the notice period.
-        // e.g. deposit day 1, immediately request redeem on day 1.  should give 0 returns.
-        if (toPeriod <= fromPeriod + noticePeriod()) {
-            return 0;
-        }
+    /// @dev yield accrues up to the `requestRedeemPeriod` (as opposed to the `redeemPeriod`)
+    function calcYield(uint256 principal, uint256 depositPeriod, uint256 redeemPeriod)
+        public
+        view
+        returns (uint256 yield)
+    {
+        uint256 requestRedeemPeriod = redeemPeriod > noticePeriod() ? redeemPeriod - noticePeriod() : 0;
+
+        if (requestRedeemPeriod <= depositPeriod) return 0; // no yield when deposit and requestRedeems are the same period
 
-        return _yieldStrategy.calcYield(address(this), principal, fromPeriod, toPeriod);
+        return _yieldStrategy.calcYield(address(this), principal, depositPeriod, requestRedeemPeriod);
     }
 
     /// @dev price is not used in Vault calculations.  however, 1 asset = 1 share, implying a price of 1

diff --git a/packages/contracts/test/src/timelock/TimelockAsyncUnlockTest.t.sol b/packages/contracts/test/src/timelock/TimelockAsyncUnlockTest.t.sol
@@ -508,6 +508,20 @@ contract TimelockAsyncUnlockTest is Test {
         );
     }
 
+    function test__TimelockAsyncUnlock__RequestUnlockInvalidArrayLengthReverts() public {
+        uint256[] memory depositPeriods_ = new uint256[](2);
+        uint256[] memory amounts_ = new uint256[](1);
+
+        vm.expectRevert(
+            abi.encodeWithSelector(
+                TimelockAsyncUnlock.TimelockAsyncUnlock__InvalidArrayLength.selector,
+                depositPeriods_.length,
+                amounts_.length
+            )
+        );
+        asyncUnlock.requestUnlock(alice, depositPeriods_, amounts_);
+    }
+
     function _asSingletonArray(uint256 element) internal pure returns (uint256[] memory array) {
         array = new uint256[](1);
         array[0] = element;

diff --git a/packages/contracts/test/src/yield/LiquidContinuousMultiTokenVaultTest.t.sol b/packages/contracts/test/src/yield/LiquidContinuousMultiTokenVaultTest.t.sol
@@ -63,7 +63,7 @@ contract LiquidContinuousMultiTokenVaultTest is LiquidContinuousMultiTokenVaultT
         LiquidContinuousMultiTokenVault liquidVault = _liquidVault; // _createLiquidContinueMultiTokenVault(_vaultParams);
 
         TestParamSet.TestParam memory testParams =
-            TestParamSet.TestParam({ principal: 2_000 * _scale, depositPeriod: 10, redeemPeriod: 70 });
+            TestParamSet.TestParam({ principal: 2_000 * _scale, depositPeriod: 10, redeemPeriod: 71 });
 
         uint256 assetStartBalance = _asset.balanceOf(alice);
 
@@ -283,13 +283,15 @@ contract LiquidContinuousMultiTokenVaultTest is LiquidContinuousMultiTokenVaultT
     function test__LiquidContinuousMultiTokenVault__50k_Returns() public view {
         uint256 deposit = 50_000 * _scale;
 
+        uint256 tenorPlusNoticePeriod = _liquidVault.TENOR() + _liquidVault.noticePeriod();
+
         // verify returns
-        uint256 actualYield = _liquidVault.calcYield(deposit, 0, _liquidVault.TENOR());
+        uint256 actualYield = _liquidVault.calcYield(deposit, 0, tenorPlusNoticePeriod);
         assertEq(416_666666, actualYield, "interest not correct for $50k deposit after 30 days");
 
         // verify principal + returns
         uint256 actualShares = _liquidVault.convertToShares(deposit);
-        uint256 actualReturns = _liquidVault.convertToAssetsForDepositPeriod(actualShares, 0, _liquidVault.TENOR());
+        uint256 actualReturns = _liquidVault.convertToAssetsForDepositPeriod(actualShares, 0, tenorPlusNoticePeriod);
         assertEq(50_416_666666, actualReturns, "principal + interest not correct for $50k deposit after 30 days");
     }
 
@@ -843,4 +845,57 @@ contract LiquidContinuousMultiTokenVaultTest is LiquidContinuousMultiTokenVaultT
         uint256 assets = _liquidVault.redeem(shares, alice, alice);
         assertEq(principal, assets, "assets should be the same as principal");
     }
+
+    function test__LiquidContinuousMultiTokenVault__CalcYieldEdgeCases() public view {
+        uint256 principal = 1_000_000_000 * _scale;
+        uint256 zeroPeriod = 0;
+        uint256 hundredPeriod = 100;
+        uint256 noticePeriod = _liquidVault.noticePeriod();
+
+        // check scenarios with zero returns
+        assertEq(
+            0,
+            _liquidVault.calcYield(principal, zeroPeriod, zeroPeriod),
+            "no returns when redeeming at deposit period - deposit at 0"
+        );
+        assertEq(
+            0,
+            _liquidVault.calcYield(principal, hundredPeriod, hundredPeriod),
+            "no returns when redeeming at deposit period - deposit at 100"
+        );
+
+        assertEq(
+            0,
+            _liquidVault.calcYield(principal, zeroPeriod, zeroPeriod + noticePeriod),
+            "no returns when redeeming at notice period - deposit at 0"
+        );
+        assertEq(
+            0,
+            _liquidVault.calcYield(principal, hundredPeriod, hundredPeriod + noticePeriod),
+            "no returns when redeeming at notice period - deposit at 100"
+        );
+
+        assertEq(
+            0,
+            _liquidVault.calcYield(principal, 1, zeroPeriod),
+            "zero yield redeem less than deposit period - redeem at 0"
+        );
+        assertEq(
+            0,
+            _liquidVault.calcYield(principal, hundredPeriod, hundredPeriod - 1),
+            "zero yield redeem less than deposit period - redeem at 99"
+        );
+
+        // check scenarios with returns
+        assertLt(
+            0,
+            _liquidVault.calcYield(principal, zeroPeriod, zeroPeriod + noticePeriod + 1),
+            "redeem > notice period should have yield"
+        );
+        assertLt(
+            0,
+            _liquidVault.calcYield(principal, hundredPeriod, hundredPeriod + noticePeriod + 1),
+            "redeem > notice period should have yield"
+        );
+    }
 }
diff --git a/packages/contracts/test/test/yield/LiquidContinuousMultiTokenVaultTestBase.t.sol b/packages/contracts/test/test/yield/LiquidContinuousMultiTokenVaultTestBase.t.sol
@@ -261,8 +261,11 @@ abstract contract LiquidContinuousMultiTokenVaultTestBase is IMultiTokenVaultTes
     {
         LiquidContinuousMultiTokenVault liquidVault = LiquidContinuousMultiTokenVault(address(vault));
 
+        // LiquidStone stops accruing yield at the requestRedeem period
+        uint256 requestRedeemPeriod = testParam.redeemPeriod - _liquidVault.noticePeriod();
+
         return liquidVault._yieldStrategy().calcYield(
-            address(vault), testParam.principal, testParam.depositPeriod, testParam.redeemPeriod
+            address(vault), testParam.principal, testParam.depositPeriod, requestRedeemPeriod
         );
     }