add aggregators router

pkg/interfaces/contracts/vault/IAggRouter.sol

@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+pragma solidity ^0.8.24;
+
+import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
+
+import { SwapKind } from "./VaultTypes.sol";
+import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
+
+interface IAggRouter {
+    /***************************************************************************
+                                       Swaps
+    ***************************************************************************/
+
+    /**
+     * @dev Data for the swap hook.
+     * @param sender Account initiating the swap operation
+     * @param kind Type of swap (exact in or exact out)
+     * @param pool Address of the liquidity pool
+     * @param tokenIn Token to be swapped from
+     * @param tokenOut Token to be swapped to
+     * @param amountGiven Amount given based on kind of the swap (e.g., tokenIn for exact in)
+     * @param limit Maximum or minimum amount based on the kind of swap (e.g., maxAmountIn for exact out)
+     * @param deadline Deadline for the swap
+     * @param wethIsEth If true, incoming ETH will be wrapped to WETH and outgoing WETH will be unwrapped to ETH
+     * @param userData Additional (optional) data required for the swap
+     */
+    struct SwapSingleTokenHookParams {
+        address sender;
+        SwapKind kind;
+        address pool;
+        IERC20 tokenIn;
+        IERC20 tokenOut;
+        uint256 amountGiven;
+        uint256 limit;
+        uint256 deadline;
+        bool wethIsEth;
+        bytes userData;
+    }
+
+    /**
+     * @notice Executes a swap operation with the amount of tokens sent directly to the Vault
+     * @param pool Address of the liquidity pool
+     * @param tokenIn Token to be swapped from
+     * @param tokenOut Token to be swapped to
+     * @param minAmountOut Minimum amount of tokens to be received
+     * @param deadline Deadline for the swap
+     * @param userData Additional (optional) data required for the swap
+     * @param wethIsEth If true, incoming ETH will be wrapped to WETH and outgoing WETH will be unwrapped to ETH
+     * @return amountOut Calculated amount of output tokens to be received in exchange for the given input tokens
+     */
+    function swapSingleTokenDonated(
+        address pool,
+        IERC20 tokenIn,
+        IERC20 tokenOut,
+        uint256 exactAmountIn,
+        uint256 minAmountOut,
+        uint256 deadline,
+        bool wethIsEth,
+        bytes calldata userData
+    ) external payable returns (uint256 amountOut);
+}

pkg/pool-stable/test/gas/.hardhat-snapshots/[StablePool - Standard] add liquidity proportional

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-179.1k
+179.3k

pkg/pool-stable/test/gas/.hardhat-snapshots/[StablePool - Standard] add liquidity single token exact out - warm slots

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-171.6k
+171.8k

pkg/pool-stable/test/gas/.hardhat-snapshots/[StablePool - Standard] add liquidity unbalanced - warm slots

@@ -1 +1 @@
-214.4k
+214.5k

pkg/pool-stable/test/gas/.hardhat-snapshots/[StablePool - Standard] remove liquidity proportional

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-167.2k
+167.3k

pkg/pool-stable/test/gas/.hardhat-snapshots/[StablePool - Standard] remove liquidity single token exact in - warm slots

@@ -1 +1 @@
-166.4k
+166.5k

pkg/pool-stable/test/gas/.hardhat-snapshots/[StablePool - Standard] remove liquidity single token exact out - warm slots

@@ -1 +1 @@
-176.7k
+176.8k

pkg/pool-stable/test/gas/.hardhat-snapshots/[StablePool - Standard] swap single token exact in with fees - cold slots

@@ -1 +1 @@
-178.5k
+178.7k

pkg/pool-stable/test/gas/.hardhat-snapshots/[StablePool - Standard] swap single token exact in with fees - warm slots

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-164.7k
+164.8k

pkg/pool-stable/test/gas/.hardhat-snapshots/[StablePool - With rate] add liquidity proportional

@@ -1 +1 @@
-234.2k
+234.4k

pkg/pool-stable/test/gas/.hardhat-snapshots/[StablePool - With rate] add liquidity single token exact out - warm slots

@@ -1 +1 @@
-193.0k
+193.2k

pkg/pool-stable/test/gas/.hardhat-snapshots/[StablePool - With rate] add liquidity unbalanced - warm slots

@@ -1 +1 @@
-230.5k
+230.6k

pkg/pool-stable/test/gas/.hardhat-snapshots/[StablePool - With rate] remove liquidity proportional

@@ -1 +1 @@
-222.1k
+222.3k

pkg/pool-stable/test/gas/.hardhat-snapshots/[StablePool - With rate] remove liquidity single token exact in - warm slots

@@ -1 +1 @@
-187.7k
+187.8k

pkg/pool-stable/test/gas/.hardhat-snapshots/[StablePool - With rate] remove liquidity single token exact out - warm slots

@@ -1 +1 @@
-197.9k
+198.0k

pkg/pool-stable/test/gas/.hardhat-snapshots/[StablePool - With rate] swap single token exact in with fees - cold slots

@@ -1 +1 @@
-211.6k
+211.8k

pkg/pool-stable/test/gas/.hardhat-snapshots/[StablePool - With rate] swap single token exact in with fees - warm slots

@@ -1 +1 @@
-180.6k
+180.8k

pkg/pool-stable/test/gas/.hardhat-snapshots/[StablePool] donation

@@ -1 +1 @@
-177.9k
+178.0k

pkg/vault/contracts/AggRouter.sol

@@ -0,0 +1,133 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+pragma solidity ^0.8.24;
+
+import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
+import { SafeERC20 } from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
+import { Address } from "@openzeppelin/contracts/utils/Address.sol";
+import { IPermit2 } from "permit2/src/interfaces/IPermit2.sol";
+
+import { IVault } from "@balancer-labs/v3-interfaces/contracts/vault/IVault.sol";
+
+import { IAggRouter } from "@balancer-labs/v3-interfaces/contracts/vault/IAggRouter.sol";
+import { IWETH } from "@balancer-labs/v3-interfaces/contracts/solidity-utils/misc/IWETH.sol";
+import "@balancer-labs/v3-interfaces/contracts/vault/VaultTypes.sol";
+
+import {
+    ReentrancyGuardTransient
+} from "@balancer-labs/v3-solidity-utils/contracts/openzeppelin/ReentrancyGuardTransient.sol";
+
+import { RouterCommon } from "./RouterCommon.sol";
+
+contract AggRouter is IAggRouter, RouterCommon, ReentrancyGuardTransient {
+    using SafeERC20 for IERC20;
+    using Address for address payable;
+
+    constructor(IVault vault, IWETH weth, IPermit2 permit2) RouterCommon(vault, weth, permit2) {
+        // solhint-disable-previous-line no-empty-blocks
+    }
+
+    /// @inheritdoc IAggRouter
+    function swapSingleTokenDonated(
+        address pool,
+        IERC20 tokenIn,
+        IERC20 tokenOut,
+        uint256 exactAmountIn,
+        uint256 minAmountOut,
+        uint256 deadline,
+        bool wethIsEth,
+        bytes calldata userData
+    ) external payable saveSender(msg.sender) returns (uint256) {
+        return
+            abi.decode(
+                _vault.unlock(
+                    _swapSingleTokenArgs(
+                        pool,
+                        tokenIn,
+                        tokenOut,
+                        exactAmountIn,
+                        minAmountOut,
+                        deadline,
+                        wethIsEth,
+                        userData
+                    )
+                ),
+                (uint256)
+            );
+    }
+
+    // Addresses stack-too-deep.
+    function _swapSingleTokenArgs(
+        address pool,
+        IERC20 tokenIn,
+        IERC20 tokenOut,
+        uint256 exactAmountIn,
+        uint256 minAmountOut,
+        uint256 deadline,
+        bool wethIsEth,
+        bytes calldata userData
+    ) private view returns (bytes memory) {
+        return
+            abi.encodeWithSelector(
+                AggRouter.swapSingleTokenDonatedHook.selector,
+                SwapSingleTokenHookParams({
+                    sender: msg.sender,
+                    kind: SwapKind.EXACT_IN,
+                    pool: pool,
+                    tokenIn: tokenIn,
+                    tokenOut: tokenOut,
+                    amountGiven: exactAmountIn,
+                    limit: minAmountOut,
+                    deadline: deadline,
+                    wethIsEth: wethIsEth,
+                    userData: userData
+                })
+            );
+    }
+
+    /**
+     * @notice Hook for swaps.
+     * @dev Can only be called by the Vault. Also handles native ETH.
+     * @param params Swap parameters (see IRouter for struct definition)
+     * @return Token amount calculated by the pool math (e.g., amountOut for a exact in swap)
+     */
+    function swapSingleTokenDonatedHook(
+        SwapSingleTokenHookParams calldata params
+    ) external nonReentrant onlyVault returns (uint256) {
+        (uint256 amountCalculated, uint256 amountIn, uint256 amountOut) = _swapHook(params);
+
+        IERC20 tokenIn = params.tokenIn;
+
+        _vault.settle(tokenIn, amountIn);
+        _sendTokenOut(params.sender, params.tokenOut, amountOut, params.wethIsEth);
+
+        if (tokenIn == _weth) {
+            // Return the rest of ETH to sender
+            _returnEth(params.sender);
+        }
+
+        return amountCalculated;
+    }
+
+    function _swapHook(
+        SwapSingleTokenHookParams calldata params
+    ) internal returns (uint256 amountCalculated, uint256 amountIn, uint256 amountOut) {
+        // The deadline is timestamp-based: it should not be relied upon for sub-minute accuracy.
+        // solhint-disable-next-line not-rely-on-time
+        if (block.timestamp > params.deadline) {
+            revert SwapDeadline();
+        }
+
+        (amountCalculated, amountIn, amountOut) = _vault.swap(
+            VaultSwapParams({
+                kind: params.kind,
+                pool: params.pool,
+                tokenIn: params.tokenIn,
+                tokenOut: params.tokenOut,
+                amountGivenRaw: params.amountGiven,
+                limitRaw: params.limit,
+                userData: params.userData
+            })
+        );
+    }
+}

pkg/vault/contracts/test/AggRouterMock.sol

@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+pragma solidity ^0.8.24;
+
+import "../AggRouter.sol";
+
+contract AggRouterMock is AggRouter {
+    constructor(IVault vault, IWETH weth, IPermit2 permit2) AggRouter(vault, weth, permit2) {}
+}

pkg/vault/test/.contract-sizes/AggRouter

@@ -0,0 +1,2 @@
+Bytecode	6.289
+InitCode	6.948

pkg/vault/test/ContractSizes.ts

@@ -11,6 +11,7 @@ describe('ContractSizes', function () {
       'Router',
       'BatchRouter',
       'CompositeLiquidityRouter',
+      'AggRouter',
     ]) {
       const artifact = getArtifact(`v3-vault/${contractName}`);