chore: merge dev

.forge-snapshots/newBCoWFactory.snap

@@ -1 +1 @@
-4889580
+4899289

.forge-snapshots/newBCoWPool.snap

@@ -1 +1 @@
-4033896
+4042925

.forge-snapshots/newBFactory.snap

@@ -1 +1 @@
-4130621
+4140477

.forge-snapshots/newBPool.snap

@@ -1 +1 @@
-3477592
+3486610

.forge-snapshots/swapExactAmountIn.snap

@@ -1 +1 @@
-104914
+104920

.forge-snapshots/swapExactAmountInInverse.snap

@@ -1 +1 @@
-114583
+114589

package.json

@@ -42,6 +42,7 @@
     "@cowprotocol/contracts": "github:cowprotocol/contracts.git#a10f40788a",
     "@openzeppelin/contracts": "5.0.2",
     "composable-cow": "github:cowprotocol/composable-cow.git#24d556b",
+    "cow-amm": "github:cowprotocol/cow-amm.git#6566128",
     "solmate": "github:transmissions11/solmate#c892309"
   },
   "devDependencies": {

remappings.txt

@@ -5,6 +5,9 @@ solmate/=node_modules/solmate/src
 @cowprotocol/=node_modules/@cowprotocol/contracts/src/contracts
 cowprotocol/=node_modules/@cowprotocol/contracts/src/
 @composable-cow/=node_modules/composable-cow/
+@cow-amm/=node_modules/cow-amm/src
+lib/openzeppelin/=node_modules/@openzeppelin
 
 contracts/=src/contracts
 interfaces/=src/interfaces
+libraries/=src/libraries

src/contracts/BCoWHelper.sol

@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+pragma solidity 0.8.25;
+
+import {IBCoWFactory} from 'interfaces/IBCoWFactory.sol';
+import {IBCoWPool} from 'interfaces/IBCoWPool.sol';
+
+import {ICOWAMMPoolHelper} from '@cow-amm/interfaces/ICOWAMMPoolHelper.sol';
+import {GetTradeableOrder} from '@cow-amm/libraries/GetTradeableOrder.sol';
+
+import {IERC20} from '@cowprotocol/interfaces/IERC20.sol';
+import {GPv2Interaction} from '@cowprotocol/libraries/GPv2Interaction.sol';
+import {GPv2Order} from '@cowprotocol/libraries/GPv2Order.sol';
+
+import {BMath} from 'contracts/BMath.sol';
+
+/**
+ * @title BCoWHelper
+ * @notice Helper contract that allows to trade on CoW Swap Protocol.
+ * @dev This contract supports only 2-token equal-weights pools.
+ */
+contract BCoWHelper is ICOWAMMPoolHelper, BMath {
+  using GPv2Order for GPv2Order.Data;
+
+  /// @notice The app data used by this helper's factory.
+  bytes32 internal immutable _APP_DATA;
+
+  /// @inheritdoc ICOWAMMPoolHelper
+  // solhint-disable-next-line style-guide-casing
+  address public immutable factory;
+
+  constructor(address factory_) {
+    factory = factory_;
+    _APP_DATA = IBCoWFactory(factory_).APP_DATA();
+  }
+
+  /// @inheritdoc ICOWAMMPoolHelper
+  function order(
+    address pool,
+    uint256[] calldata prices
+  )
+    external
+    view
+    returns (
+      GPv2Order.Data memory order_,
+      GPv2Interaction.Data[] memory preInteractions,
+      GPv2Interaction.Data[] memory postInteractions,
+      bytes memory sig
+    )
+  {
+    address[] memory tokens_ = tokens(pool);
+
+    GetTradeableOrder.GetTradeableOrderParams memory params = GetTradeableOrder.GetTradeableOrderParams({
+      pool: pool,
+      token0: IERC20(tokens_[0]),
+      token1: IERC20(tokens_[1]),
+      // The price of this function is expressed as amount of
+      // token1 per amount of token0. The `prices` vector is
+      // expressed the other way around.
+      priceNumerator: prices[1],
+      priceDenominator: prices[0],
+      appData: _APP_DATA
+    });
+
+    order_ = GetTradeableOrder.getTradeableOrder(params);
+
+    {
+      // NOTE: Using calcOutGivenIn for the sell amount in order to avoid possible rounding
+      // issues that may cause invalid orders. This prevents CoW Protocol back-end from generating
+      // orders that may be ignored due to rounding-induced reverts.
+
+      uint256 balanceToken0 = IERC20(tokens_[0]).balanceOf(pool);
+      uint256 balanceToken1 = IERC20(tokens_[1]).balanceOf(pool);
+      (uint256 balanceIn, uint256 balanceOut) =
+        address(order_.buyToken) == tokens_[0] ? (balanceToken0, balanceToken1) : (balanceToken1, balanceToken0);
+
+      order_.sellAmount = calcOutGivenIn({
+        tokenBalanceIn: balanceIn,
+        tokenWeightIn: 1e18,
+        tokenBalanceOut: balanceOut,
+        tokenWeightOut: 1e18,
+        tokenAmountIn: order_.buyAmount,
+        swapFee: 0
+      });
+    }
+
+    // A ERC-1271 signature on CoW Protocol is composed of two parts: the
+    // signer address and the valid ERC-1271 signature data for that signer.
+    bytes memory eip1271sig;
+    eip1271sig = abi.encode(order_);
+    sig = abi.encodePacked(pool, eip1271sig);
+
+    // Generate the order commitment pre-interaction
+    bytes32 domainSeparator = IBCoWPool(pool).SOLUTION_SETTLER_DOMAIN_SEPARATOR();
+    bytes32 orderCommitment = order_.hash(domainSeparator);
+
+    preInteractions = new GPv2Interaction.Data[](1);
+    preInteractions[0] = GPv2Interaction.Data({
+      target: pool,
+      value: 0,
+      callData: abi.encodeWithSelector(IBCoWPool.commit.selector, orderCommitment)
+    });
+
+    return (order_, preInteractions, postInteractions, sig);
+  }
+
+  /// @inheritdoc ICOWAMMPoolHelper
+  function tokens(address pool) public view virtual returns (address[] memory tokens_) {
+    // reverts in case pool is not deployed by the helper's factory
+    if (!IBCoWFactory(factory).isBPool(pool)) {
+      revert PoolDoesNotExist();
+    }
+
+    // call reverts with `BPool_PoolNotFinalized()` in case pool is not finalized
+    tokens_ = IBCoWPool(pool).getFinalTokens();
+
+    // reverts in case pool is not supported (non-2-token pool)
+    if (tokens_.length != 2) {
+      revert PoolDoesNotExist();
+    }
+    // reverts in case pool is not supported (non-equal weights)
+    if (IBCoWPool(pool).getNormalizedWeight(tokens_[0]) != IBCoWPool(pool).getNormalizedWeight(tokens_[1])) {
+      revert PoolDoesNotExist();
+    }
+  }
+}

src/contracts/BConst.sol

@@ -17,7 +17,7 @@ contract BConst {
   /// @notice The minimum swap fee that can be set.
   uint256 public constant MIN_FEE = BONE / 10 ** 6;
   /// @notice The maximum swap fee that can be set.
-  uint256 public constant MAX_FEE = BONE / 10;
+  uint256 public constant MAX_FEE = BONE - MIN_FEE;
   /// @notice The immutable exit fee percentage
   uint256 public constant EXIT_FEE = 0;
 

src/contracts/BPool.sol

@@ -280,8 +280,6 @@ contract BPool is BToken, BMath, IBPool {
 
     _pullUnderlying(tokenIn, msg.sender, tokenAmountIn);
     _pushUnderlying(tokenOut, msg.sender, tokenAmountOut);
-
-    return (tokenAmountOut, spotPriceAfter);
   }
 
   /// @inheritdoc IBPool
@@ -339,8 +337,6 @@ contract BPool is BToken, BMath, IBPool {
 
     _pullUnderlying(tokenIn, msg.sender, tokenAmountIn);
     _pushUnderlying(tokenOut, msg.sender, tokenAmountOut);
-
-    return (tokenAmountIn, spotPriceAfter);
   }
 
   /// @inheritdoc IBPool
@@ -370,8 +366,6 @@ contract BPool is BToken, BMath, IBPool {
     _mintPoolShare(poolAmountOut);
     _pushPoolShare(msg.sender, poolAmountOut);
     _pullUnderlying(tokenIn, msg.sender, tokenAmountIn);
-
-    return poolAmountOut;
   }
 
   /// @inheritdoc IBPool
@@ -405,8 +399,6 @@ contract BPool is BToken, BMath, IBPool {
     _mintPoolShare(poolAmountOut);
     _pushPoolShare(msg.sender, poolAmountOut);
     _pullUnderlying(tokenIn, msg.sender, tokenAmountIn);
-
-    return tokenAmountIn;
   }
 
   /// @inheritdoc IBPool
@@ -440,8 +432,6 @@ contract BPool is BToken, BMath, IBPool {
     _burnPoolShare(bsub(poolAmountIn, exitFee));
     _pushPoolShare(FACTORY, exitFee);
     _pushUnderlying(tokenOut, msg.sender, tokenAmountOut);
-
-    return tokenAmountOut;
   }
 
   /// @inheritdoc IBPool
@@ -477,12 +467,10 @@ contract BPool is BToken, BMath, IBPool {
     _burnPoolShare(bsub(poolAmountIn, exitFee));
     _pushPoolShare(FACTORY, exitFee);
     _pushUnderlying(tokenOut, msg.sender, tokenAmountOut);
-
-    return poolAmountIn;
   }
 
   /// @inheritdoc IBPool
-  function getSpotPrice(address tokenIn, address tokenOut) external view _viewlock_ returns (uint256 spotPrice) {
+  function getSpotPrice(address tokenIn, address tokenOut) external view _viewlock_ returns (uint256) {
     if (!_records[tokenIn].bound) {
       revert BPool_TokenNotBound();
     }
@@ -492,19 +480,17 @@ contract BPool is BToken, BMath, IBPool {
     Record storage inRecord = _records[tokenIn];
     Record storage outRecord = _records[tokenOut];
 
-    spotPrice = calcSpotPrice(
+    return calcSpotPrice(
       IERC20(tokenIn).balanceOf(address(this)),
       inRecord.denorm,
       IERC20(tokenOut).balanceOf(address(this)),
       outRecord.denorm,
       _swapFee
     );
-
-    return spotPrice;
   }
 
   /// @inheritdoc IBPool
-  function getSpotPriceSansFee(address tokenIn, address tokenOut) external view _viewlock_ returns (uint256 spotPrice) {
+  function getSpotPriceSansFee(address tokenIn, address tokenOut) external view _viewlock_ returns (uint256) {
     if (!_records[tokenIn].bound) {
       revert BPool_TokenNotBound();
     }
@@ -514,15 +500,13 @@ contract BPool is BToken, BMath, IBPool {
     Record storage inRecord = _records[tokenIn];
     Record storage outRecord = _records[tokenOut];
 
-    spotPrice = calcSpotPrice(
+    return calcSpotPrice(
       IERC20(tokenIn).balanceOf(address(this)),
       inRecord.denorm,
       IERC20(tokenOut).balanceOf(address(this)),
       outRecord.denorm,
       0
     );
-
-    return spotPrice;
   }
 
   /// @inheritdoc IBPool
@@ -531,8 +515,8 @@ contract BPool is BToken, BMath, IBPool {
   }
 
   /// @inheritdoc IBPool
-  function isBound(address t) external view returns (bool) {
-    return _records[t].bound;
+  function isBound(address token) external view returns (bool) {
+    return _records[token].bound;
   }
 
   /// @inheritdoc IBPool
@@ -541,12 +525,12 @@ contract BPool is BToken, BMath, IBPool {
   }
 
   /// @inheritdoc IBPool
-  function getCurrentTokens() external view _viewlock_ returns (address[] memory tokens) {
+  function getCurrentTokens() external view _viewlock_ returns (address[] memory) {
     return _tokens;
   }
 
   /// @inheritdoc IBPool
-  function getFinalTokens() external view _viewlock_ _finalized_ returns (address[] memory tokens) {
+  function getFinalTokens() external view _viewlock_ _finalized_ returns (address[] memory) {
     return _tokens;
   }
 

src/contracts/BToken.sol

@@ -18,7 +18,7 @@ contract BToken is ERC20 {
    */
   function increaseApproval(address spender, uint256 amount) external returns (bool success) {
     _approve(msg.sender, spender, allowance(msg.sender, spender) + amount);
-    return true;
+    success = true;
   }
 
   /**
@@ -34,7 +34,7 @@ contract BToken is ERC20 {
     } else {
       _approve(msg.sender, spender, oldValue - amount);
     }
-    return true;
+    success = true;
   }
 
   /**