chore: Add BalancerSwapExecutor

evm/test/BalancerSwapExecutor.t.sol

@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.13;
+
+import "./SwapExecutorTest.sol";
+import "../src/balancer-v2/BalancerSwapExecutor.sol";
+
+contract TestBalancerSwapExecutor is SwapExecutorTest {
+    BalancerSwapExecutor balancer;
+    IERC20 USDC = IERC20(USDC_ADDR);
+    IERC20 USDT = IERC20(USDT_ADDR);
+
+    constructor() {}
+
+    function setUp() public {
+        //Fork
+        uint256 forkBlock = 16000000;
+        vm.createSelectFork(vm.rpcUrl("mainnet"), forkBlock);
+
+        //Setup
+        balancer = new BalancerSwapExecutor();
+    }
+
+    function testBalancerSwap() public {
+        //Set up
+        uint256 sellAmount = 1000_000000;
+        uint256 expectedAmount = 998_919380; //Swap 1k USDT for 998 USDC
+        bool exactOut = false;
+        // This is required because balancer does a transferFrom sender.
+        // That also means we need to do this approval with our swapRouter.
+        bool tokenApprovalNeeded = true;
+        bytes memory protocolData = abi.encodePacked(
+            USDT_ADDR,
+            USDC_ADDR,
+            DAI_USDC_USDT_balancer,
+            bob,
+            exactOut,
+            tokenApprovalNeeded
+        );
+
+        // Logic
+        vm.prank(address(balancer));
+        deal(USDT_ADDR, address(balancer), sellAmount);
+        vm.prank(executor);
+        uint256 responseAmount = balancer.swap(sellAmount, protocolData);
+
+        //Assertions
+        assertEq(responseAmount, expectedAmount);
+        assertEq(USDC.balanceOf(bob), expectedAmount);
+        assertEq(USDT.balanceOf(address(balancer)), 0);
+    }
+
+    function testBalancerExactOutSwap() public {
+        //Set up
+        uint256 buyAmount = 1000_979168;
+        uint256 expectedSellAmount = 1000 * 10 ** 6;
+        bool exactOut = true;
+        bool tokenApprovalNeeded = true;
+        bytes memory protocolData = abi.encodePacked(
+            USDC_ADDR,
+            USDT_ADDR,
+            DAI_USDC_USDT_balancer,
+            bob,
+            exactOut,
+            tokenApprovalNeeded
+        );
+
+        //Logic
+        // This is required because balancer does a transferFrom sender.
+        // That also means we need to do this approval with our swapRouter.
+        vm.prank(address(balancer));
+
+        deal(USDC_ADDR, address(balancer), expectedSellAmount);
+        vm.prank(executor);
+        uint256 responseAmount = balancer.swap(buyAmount, protocolData);
+
+        // //Assertions
+        assertEq(responseAmount, expectedSellAmount);
+        assertEq(USDT.balanceOf(bob), buyAmount);
+        assertEq(USDC.balanceOf(address(balancer)), 0);
+    }
+}

evm/test/Constants.sol

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+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.13;
+
+contract Constants {
+    address executor = address(1239501235123412541234); //executor=us || cowswap
+    address admin = address(12395012351212343412541234); //admin=us
+    address bob = address(123); //bob=someone!=us
+
+    // tokens
+    address WETH_ADDR = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;
+    address USDT_ADDR = 0xdAC17F958D2ee523a2206206994597C13D831ec7;
+    address USDC_ADDR = 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48;
+    address DAI_ADDR = 0x6B175474E89094C44Da98b954EedeAC495271d0F;
+    address WBTC_ADDR = 0x2260FAC5E5542a773Aa44fBCfeDf7C193bc2C599;
+    address LDO_ADDR = 0x5A98FcBEA516Cf06857215779Fd812CA3beF1B32;
+    address CRV_ADDR = 0xD533a949740bb3306d119CC777fa900bA034cd52;
+
+    // balancer
+    address balancerVault = 0xBA12222222228d8Ba445958a75a0704d566BF2C8;
+    bytes32 DAI_USDC_USDT_balancer = bytes32(
+        0x06df3b2bbb68adc8b0e302443692037ed9f91b42000000000000000000000063
+    );
+}

evm/test/SwapExecutorTest.sol

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+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.13;
+
+import "forge-std/Test.sol";
+import "openzeppelin-contracts/contracts/interfaces/IERC20.sol";
+import "./Constants.sol";
+
+contract SwapExecutorTest is Test, Constants {
+    function twoTokens(address token0, address token1)
+        internal
+        pure
+        returns (IERC20[] memory tokens)
+    {
+        tokens = new IERC20[](2);
+        tokens[0] = IERC20(token0);
+        tokens[1] = IERC20(token1);
+    }
+}