fix: Support Euler in swapExactInput

Do the token transfers before calling swap on the pool manager

Took 13 minutes


Took 10 seconds

foundry/src/executors/UniswapV4Executor.sol

@@ -332,6 +332,7 @@ contract UniswapV4Executor is
         uint128 amountOut = 0;
         Currency swapCurrencyIn = currencyIn;
         uint256 swapAmountIn = amountIn;
+        _settle(currencyIn, amountIn, transferType);
         unchecked {
             uint256 pathLength = path.length;
             PathKey calldata pathKey;
@@ -353,12 +354,6 @@ contract UniswapV4Executor is
             }
         }
 
-        uint256 amount = _getFullDebt(currencyIn);
-        if (amount > amountIn) {
-            revert UniswapV4Executor__V4TooMuchRequested(amountIn, amount);
-        }
-        _settle(currencyIn, amount, transferType);
-
         _take(
             swapCurrencyIn, // at the end of the loop this is actually currency out
             receiver,
@@ -409,21 +404,6 @@ contract UniswapV4Executor is
         amount = uint256(_amount);
     }
 
-    /// @notice Obtain the full amount owed by this contract (negative delta)
-    /// @param currency Currency to get the delta for
-    /// @return amount The amount owed by this contract as a uint256
-    function _getFullDebt(Currency currency)
-        internal
-        view
-        returns (uint256 amount)
-    {
-        int256 _amount = poolManager.currencyDelta(address(this), currency);
-        // If the amount is positive, it should be taken not settled.
-        if (_amount > 0) revert UniswapV4Executor__DeltaNotNegative(currency);
-        // Casting is safe due to limits on the total supply of a pool
-        amount = uint256(-_amount);
-    }
-
     /**
      * @notice Pays and settles a currency to the pool manager.
      * @dev The implementing contract must ensure that the `payer` is a secure address.

foundry/test/protocols/UniswapV4.t.sol

@@ -282,6 +282,7 @@ contract UniswapV4ExecutorTestForEuler is Constants, TestUtils {
     UniswapV4ExecutorExposed uniswapV4Exposed;
     IERC20 USDT = IERC20(USDT_ADDR);
     IERC20 RLUSD = IERC20(RLUSD_ADDR);
+    IERC20 WBTC = IERC20(WBTC_ADDR);
 
     function setUp() public {
         uint256 forkBlock = 23535338;
@@ -322,6 +323,82 @@ contract UniswapV4ExecutorTestForEuler is Constants, TestUtils {
         );
         assertTrue(USDT.balanceOf(ALICE) == amountOut);
     }
+
+    function testMultipleSwapEulerLowBalance() public {
+        // RLUSD -(euler)-> USDT -> WBTC
+        uint256 amountIn = 134187695711754971245517404;
+        deal(RLUSD_ADDR, address(uniswapV4Exposed), amountIn);
+        address eulerProxy = 0xe1Ce9AF672f8854845E5474400B6ddC7AE458a10;
+        uint256 rlusdEulerBalanceBefore = RLUSD.balanceOf(eulerProxy);
+
+        UniswapV4Executor.UniswapV4Pool[] memory pools =
+            new UniswapV4Executor.UniswapV4Pool[](2);
+        pools[0] = UniswapV4Executor.UniswapV4Pool({
+            intermediaryToken: USDT_ADDR,
+            fee: uint24(50),
+            tickSpacing: int24(1),
+            hook: address(0xF87ACF8428F2f9403AAA0256A7272d6549ECa8A8),
+            hookData: bytes("")
+        });
+        pools[1] = UniswapV4Executor.UniswapV4Pool({
+            intermediaryToken: WBTC_ADDR,
+            fee: uint24(3000),
+            tickSpacing: int24(60),
+            hook: address(0),
+            hookData: bytes("")
+        });
+
+        bytes memory data = UniswapV4Utils.encodeExactInput(
+            RLUSD_ADDR,
+            WBTC_ADDR,
+            true,
+            RestrictTransferFrom.TransferType.Transfer,
+            ALICE,
+            pools
+        );
+
+        uint256 amountOut = uniswapV4Exposed.swap(amountIn, data);
+        assertEq(
+            RLUSD.balanceOf(eulerProxy), rlusdEulerBalanceBefore + amountIn
+        );
+        assertTrue(WBTC.balanceOf(ALICE) == amountOut);
+    }
+
+    function testMultipleSwapLastSwapEuler() public {
+        // USDC -> RLUSD -(euler)- > USDT
+        // Sanity check to see if a grouped swap with Euler in the last hop works
+        uint256 amountIn = 134187695711754971245517404;
+        deal(USDC_ADDR, address(uniswapV4Exposed), amountIn);
+
+        UniswapV4Executor.UniswapV4Pool[] memory pools =
+            new UniswapV4Executor.UniswapV4Pool[](2);
+        pools[0] = UniswapV4Executor.UniswapV4Pool({
+            intermediaryToken: RLUSD_ADDR,
+            fee: uint24(500),
+            tickSpacing: int24(10),
+            hook: address(0),
+            hookData: bytes("")
+        });
+        pools[1] = UniswapV4Executor.UniswapV4Pool({
+            intermediaryToken: USDT_ADDR,
+            fee: uint24(50),
+            tickSpacing: int24(1),
+            hook: address(0xF87ACF8428F2f9403AAA0256A7272d6549ECa8A8),
+            hookData: bytes("")
+        });
+
+        bytes memory data = UniswapV4Utils.encodeExactInput(
+            USDC_ADDR,
+            USDT_ADDR,
+            false,
+            RestrictTransferFrom.TransferType.Transfer,
+            ALICE,
+            pools
+        );
+
+        uint256 amountOut = uniswapV4Exposed.swap(amountIn, data);
+        assertTrue(USDT.balanceOf(ALICE) == amountOut);
+    }
 }
 
 contract TychoRouterForBalancerV3Test is TychoRouterTestSetup {