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);
+    }
+}