feat: UniswapV2 SwapExecutor

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foundry/src/executors/Uniswapv2SwapExecutor.sol

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+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.28;
+
+import "@uniswap-v2/contracts/interfaces/IUniswapV2Pair.sol";
+import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
+import {ISwapExecutor} from "../interfaces/ISwapExecutor.sol";
+
+contract UniswapV2SwapExecutor is ISwapExecutor {
+    using SafeERC20 for IERC20;
+
+    function swap(uint256 givenAmount, bytes calldata data)
+        external
+        returns (uint256 calculatedAmount)
+    {
+        address target;
+        address receiver;
+        bool zeroForOne;
+        bool exactOut;
+        IERC20 tokenIn;
+
+        (tokenIn, target, receiver, zeroForOne, exactOut) = _decodeData(data);
+        calculatedAmount = _getAmountOut(target, givenAmount, zeroForOne);
+        tokenIn.safeTransfer(target, givenAmount);
+
+        IUniswapV2Pair pool = IUniswapV2Pair(target);
+        if (zeroForOne) {
+            pool.swap(0, calculatedAmount, receiver, "");
+        } else {
+            pool.swap(calculatedAmount, 0, receiver, "");
+        }
+    }
+
+    function _decodeData(bytes calldata data)
+        internal
+        pure
+        returns (
+            IERC20 inToken,
+            address target,
+            address receiver,
+            bool zeroForOne,
+            bool exactOut
+        )
+    {
+        inToken = IERC20(address(bytes20(data[0:20])));
+        target = address(bytes20(data[20:40]));
+        receiver = address(bytes20(data[40:60]));
+        zeroForOne = uint8(data[60]) > 0;
+        exactOut = uint8(data[61]) > 0;
+    }
+
+    function _getAmountOut(address target, uint256 amountIn, bool zeroForOne)
+        internal
+        view
+        returns (uint256 amount)
+    {
+        IUniswapV2Pair pair = IUniswapV2Pair(target);
+        uint112 reserveIn;
+        uint112 reserveOut;
+        if (zeroForOne) {
+            // slither-disable-next-line unused-return
+            (reserveIn, reserveOut,) = pair.getReserves();
+        } else {
+            // slither-disable-next-line unused-return
+            (reserveOut, reserveIn,) = pair.getReserves();
+        }
+
+        require(reserveIn > 0 && reserveOut > 0, "L");
+        uint256 amountInWithFee = amountIn * 997;
+        uint256 numerator = amountInWithFee * uint256(reserveOut);
+        uint256 denominator = (uint256(reserveIn) * 1000) + amountInWithFee;
+        amount = numerator / denominator;
+    }
+}

foundry/src/interfaces/ISwapExecutor.sol

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+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.28;
+
+import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
+
+pragma abicoder v2;
+
+interface ISwapExecutor {
+    /**
+     * @notice Performs a swap on a liquidity pool.
+     * @dev This method can either take the amount of the input token or the amount
+     * of the output token that we would like to swap. If called with the amount of
+     * the  input token, the amount of the output token will be returned, and vice
+     * versa. Whether it is the input or output that is given, is encoded in the data
+     * parameter.
+     *
+     * Note Part of the informal interface is that the executor supports sending the received
+     *  tokens to a receiver address. If the underlying smart contract does not provide this
+     *  functionality consider adding an additional transfer in the implementation.
+     *
+     *  This function is marked as `payable` to accommodate delegatecalls, which can forward
+     *  a potential `msg.value` to it.
+     *
+     * @param givenAmount The amount of either the input token or output token to swap.
+     * @param data Data that holds information necessary to perform the swap.
+     * @return calculatedAmount The amount of either the input token or output token
+     * swapped, depending on the givenAmount inputted.
+     */
+    function swap(uint256 givenAmount, bytes calldata data)
+        external
+        returns (uint256 calculatedAmount);
+}
+
+interface ISwapExecutorErrors {
+    error InvalidParameterLength(uint256);
+    error UnknownCurveType(uint8);
+}