Refactor TrailsRouter to accept Multicall3 address as a constructor argument (#83)

* Refactor TrailsRouter to accept Multicall3 address as a constructor argument

- Updated TrailsRouter contract to initialize MULTICALL3 address via constructor instead of as an immutable variable.
- Modified deployRouter function to pass Multicall3 address during TrailsRouter deployment.
- Added a mock AlwaysFailingMulticall3 for testing purposes to simulate failure scenarios in tests.
- Updated relevant test cases to reflect changes in constructor and deployment logic.

* Update gas snapshots and modify expectedRouterAddress to include Multicall3 address

- Adjusted gas usage for various test cases in TrailsRouter and TrailsRouterTest to reflect recent performance changes.
- Updated expectedRouterAddress function in TrailsRouterDeploymentTest and TrailsRouterShimDeploymentTest to incorporate the Multicall3 address in the CREATE2 address calculation.

* Change MULTICALL3 to immutable in TrailsRouter contract

- Updated the MULTICALL3 state variable in the TrailsRouter contract to be immutable, ensuring it can only be set once during contract deployment. This change enhances gas efficiency and contract integrity.

* Update gas snapshots for TrailsRouter and TrailsRouterTest

- Adjusted gas usage metrics for various test cases in TrailsRouter and TrailsRouterTest to reflect recent performance optimizations.
- Minor updates made to individual test cases for consistency and accuracy in gas calculations.

* Update TrailsRouter contract to rename state variables to immutable variables

- Changed the comment for the MULTICALL3 variable to clarify its immutable status, enhancing code readability and consistency with naming conventions.

Author: shunkakinoki

.gas-snapshot

@@ -52,20 +52,20 @@ TrailsIntentEntrypointTest:testNonceIncrementsOnDeposit() (gas: 91830)
 TrailsIntentEntrypointTest:testPermitAmountExcessiveWithFee() (gas: 61879)
 TrailsIntentEntrypointTest:testPermitAmountInsufficientWithFee() (gas: 60889)
 TrailsIntentEntrypointTest:testVersionConstant() (gas: 10506)
-TrailsRouterDeploymentTest:test_DeployTrailsRouter_SameAddress() (gas: 1856117)
-TrailsRouterDeploymentTest:test_DeployTrailsRouter_Success() (gas: 1846511)
-TrailsRouterDeploymentTest:test_DeployedRouter_HasCorrectConfiguration() (gas: 1846307)
-TrailsRouterShimDeploymentTest:test_DeployRouterShim_SameAddress() (gas: 7530847)
-TrailsRouterShimDeploymentTest:test_DeployRouterShim_Success() (gas: 4873481)
-TrailsRouterShimDeploymentTest:test_DeployedContract_HasCorrectConfiguration() (gas: 4873526)
+TrailsRouterDeploymentTest:test_DeployTrailsRouter_SameAddress() (gas: 1864438)
+TrailsRouterDeploymentTest:test_DeployTrailsRouter_Success() (gas: 1852254)
+TrailsRouterDeploymentTest:test_DeployedRouter_HasCorrectConfiguration() (gas: 1852050)
+TrailsRouterShimDeploymentTest:test_DeployRouterShim_SameAddress() (gas: 7613006)
+TrailsRouterShimDeploymentTest:test_DeployRouterShim_Success() (gas: 4916218)
+TrailsRouterShimDeploymentTest:test_DeployedContract_HasCorrectConfiguration() (gas: 4916264)
 TrailsRouterShimTest:testConstructorValidation() (gas: 69336)
 TrailsRouterShimTest:testForwardToRouterReturnValue() (gas: 713355)
 TrailsRouterShimTest:testRouterAddressImmutable() (gas: 1391679)
 TrailsRouterShimTest:test_constructor_revert_zeroRouter() (gas: 68984)
-TrailsRouterShimTest:test_delegatecall_forwards_and_sets_sentinel_sstore_inactive() (gas: 1848663)
+TrailsRouterShimTest:test_delegatecall_forwards_and_sets_sentinel_sstore_inactive() (gas: 1848930)
 TrailsRouterShimTest:test_delegatecall_forwards_and_sets_sentinel_tstore_active() (gas: 38392)
 TrailsRouterShimTest:test_delegatecall_router_revert_bubbles_as_RouterCallFailed() (gas: 82109)
-TrailsRouterShimTest:test_delegatecall_sets_sentinel_with_sstore_when_no_tstore() (gas: 1830888)
+TrailsRouterShimTest:test_delegatecall_sets_sentinel_with_sstore_when_no_tstore() (gas: 1831155)
 TrailsRouterShimTest:test_delegatecall_sets_sentinel_with_tstore_when_supported() (gas: 20706)
 TrailsRouterShimTest:test_direct_handleSequenceDelegateCall_reverts_not_delegatecall() (gas: 9840)
 TrailsRouterShimTest:test_forwardToRouter_return_data_handling() (gas: 729052)
@@ -78,7 +78,7 @@ TrailsRouterShimTest:test_handleSequenceDelegateCall_with_eth_value() (gas: 3210
 TrailsRouterShimTest:test_handleSequenceDelegateCall_zero_call_value() (gas: 26873)
 TrailsRouterShimTest:test_sentinel_setting_with_different_op_hashes() (gas: 36405)
 TrailsRouterTest:testDelegateCallWithETH() (gas: 326226)
-TrailsRouterTest:testExecute_WithFailingMulticall() (gas: 450176)
+TrailsRouterTest:testExecute_WithFailingMulticall() (gas: 156745)
 TrailsRouterTest:testHandleSequenceDelegateCall_InjectAndCall() (gas: 72655)
 TrailsRouterTest:testHandleSequenceDelegateCall_RefundAndSweep() (gas: 85388)
 TrailsRouterTest:testHandleSequenceDelegateCall_Sweep() (gas: 48693)
@@ -133,7 +133,7 @@ TrailsRouterTest:test_pullAmountAndExecute_WithToken_ShouldTransferAndExecute()
 TrailsRouterTest:test_pullAmountAndExecute_WithValidToken_ShouldTransferAndExecute() (gas: 75490)
 TrailsRouterTest:test_pullAndExecute_WithETH_NoEthSent() (gas: 18454)
 TrailsRouterTest:test_pullAndExecute_WithETH_ShouldTransferAndExecute() (gas: 72439)
-TrailsRouterTest:test_pullAndExecute_WithFailingMulticall() (gas: 494404)
+TrailsRouterTest:test_pullAndExecute_WithFailingMulticall() (gas: 202286)
 TrailsRouterTest:test_pullAndExecute_WithToken_IncorrectValue() (gas: 60552)
 TrailsRouterTest:test_pullAndExecute_WithValidToken_ShouldTransferFullBalanceAndExecute() (gas: 77324)
 TrailsRouterTest:test_refundAndSweep_erc20_partialRefund() (gas: 110365)

script/TrailsRouter.s.sol

@@ -24,9 +24,10 @@ contract Deploy is SingletonDeployer {
 
     function deployRouter(uint256 pk) public returns (address) {
         bytes32 salt = bytes32(0);
+        address multicall3 = 0xcA11bde05977b3631167028862bE2a173976CA11;
 
-        // Deploy TrailsRouter
-        bytes memory initCode = type(TrailsRouter).creationCode;
+        // Deploy TrailsRouter with constructor arguments
+        bytes memory initCode = abi.encodePacked(type(TrailsRouter).creationCode, abi.encode(multicall3));
         address router = _deployIfNotAlready("TrailsRouter", initCode, salt, pk);
 
         return router;

src/TrailsRouter.sol

@@ -24,7 +24,15 @@ contract TrailsRouter is IDelegatedExtension, ITrailsRouter, DelegatecallGuard,
     // Immutable Variables
     // -------------------------------------------------------------------------
 
-    address public immutable MULTICALL3 = 0xcA11bde05977b3631167028862bE2a173976CA11;
+    address public immutable MULTICALL3;
+
+    // -------------------------------------------------------------------------
+    // Constructor
+    // -------------------------------------------------------------------------
+
+    constructor(address _multicall3) {
+        MULTICALL3 = _multicall3;
+    }
 
     // -------------------------------------------------------------------------
     // Errors

test/TrailsRouter.t.sol

@@ -49,6 +49,17 @@ contract RevertingReceiver {
     }
 }
 
+// Mock multicall that always fails (for testing storage conflicts)
+contract AlwaysFailingMulticall3 {
+    function aggregate3(IMulticall3.Call3[] calldata) external payable {
+        revert("MockMulticall3: forced failure");
+    }
+
+    function aggregate3Value(IMulticall3.Call3Value[] calldata) external payable {
+        revert("MockMulticall3: forced failure");
+    }
+}
+
 contract MockTarget {
     uint256 public lastAmount;
     bool public shouldRevert;
@@ -199,7 +210,7 @@ contract TrailsRouterTest is Test {
         MockMulticall3 mockMulticall3 = new MockMulticall3();
         vm.etch(0xcA11bde05977b3631167028862bE2a173976CA11, address(mockMulticall3).code);
 
-        router = new TrailsRouter();
+        router = new TrailsRouter(0xcA11bde05977b3631167028862bE2a173976CA11);
         getter = new MockSenderGetter();
         mockToken = new MockERC20("MockToken", "MTK", 18);
         failingToken = new FailingToken();
@@ -865,17 +876,13 @@ contract TrailsRouterTest is Test {
         // Save original multicall code
         bytes memory originalCode = 0xcA11bde05977b3631167028862bE2a173976CA11.code;
 
-        // Deploy and etch failing multicall
-        MockMulticall3 failingMulticall = new MockMulticall3();
+        // Deploy and etch always-failing multicall (doesn't use storage, always reverts)
+        AlwaysFailingMulticall3 failingMulticall = new AlwaysFailingMulticall3();
         vm.etch(0xcA11bde05977b3631167028862bE2a173976CA11, address(failingMulticall).code);
 
         // Verify the etch worked
         assertEq(keccak256(0xcA11bde05977b3631167028862bE2a173976CA11.code), keccak256(address(failingMulticall).code));
 
-        // Set the failure flag directly in storage since delegatecall uses caller's storage
-        // The shouldFail variable is at slot 0 in MockMulticall3
-        vm.store(address(router), bytes32(0), bytes32(uint256(1))); // Set shouldFail = true in router's storage
-
         IMulticall3.Call3[] memory calls = new IMulticall3.Call3[](1);
         calls[0] = IMulticall3.Call3({
             target: address(getter), allowFailure: false, callData: abi.encodeWithSignature("getSender()")
@@ -901,13 +908,10 @@ contract TrailsRouterTest is Test {
         // Save original multicall code
         bytes memory originalCode = 0xcA11bde05977b3631167028862bE2a173976CA11.code;
 
-        // Mock multicall3 to return failure
-        MockMulticall3 failingMulticall = new MockMulticall3();
+        // Deploy and etch always-failing multicall (doesn't use storage, always reverts)
+        AlwaysFailingMulticall3 failingMulticall = new AlwaysFailingMulticall3();
         vm.etch(0xcA11bde05977b3631167028862bE2a173976CA11, address(failingMulticall).code);
 
-        // Set the failure flag directly in storage since delegatecall uses caller's storage
-        vm.store(address(router), bytes32(0), bytes32(uint256(1))); // Set shouldFail = true in router's storage
-
         IMulticall3.Call3[] memory calls = new IMulticall3.Call3[](1);
         calls[0] = IMulticall3.Call3({
             target: address(getter), allowFailure: false, callData: abi.encodeWithSignature("getSender()")

test/TrailsRouterShim.t.sol

@@ -253,7 +253,7 @@ contract TrailsRouterShimTest is Test {
 
         // Verify sentinel by re-etching TrailsRouter and validating via delegated entrypoint
         bytes memory original = address(shimImpl).code;
-        vm.etch(holder, address(new TrailsRouter()).code);
+        vm.etch(holder, address(new TrailsRouter(0xcA11bde05977b3631167028862bE2a173976CA11)).code);
 
         address payable recipient = payable(address(0x111));
         vm.deal(holder, callValue);
@@ -309,7 +309,7 @@ contract TrailsRouterShimTest is Test {
 
         // Verify via TrailsRouter delegated validation
         bytes memory original = address(shimImpl).code;
-        vm.etch(holder, address(new TrailsRouter()).code);
+        vm.etch(holder, address(new TrailsRouter(0xcA11bde05977b3631167028862bE2a173976CA11)).code);
         address payable recipient = payable(address(0x112));
         vm.deal(holder, 1 ether);
         bytes memory data =

test/script/TrailsRouter.s.t.sol

@@ -26,7 +26,9 @@ contract TrailsRouterDeploymentTest is Test {
 
     // Expected predetermined address (calculated using CREATE2)
     function expectedRouterAddress() internal pure returns (address payable) {
-        return Create2Utils.calculateCreate2Address(type(TrailsRouter).creationCode, Create2Utils.standardSalt());
+        address multicall3 = 0xcA11bde05977b3631167028862bE2a173976CA11;
+        bytes memory initCode = abi.encodePacked(type(TrailsRouter).creationCode, abi.encode(multicall3));
+        return Create2Utils.calculateCreate2Address(initCode, Create2Utils.standardSalt());
     }
 
     // -------------------------------------------------------------------------

test/script/TrailsRouterShim.s.t.sol

@@ -27,7 +27,9 @@ contract TrailsRouterShimDeploymentTest is Test {
 
     // Expected predetermined addresses (calculated using CREATE2)
     function expectedRouterAddress() internal pure returns (address payable) {
-        return Create2Utils.calculateCreate2Address(type(TrailsRouter).creationCode, Create2Utils.standardSalt());
+        address multicall3 = 0xcA11bde05977b3631167028862bE2a173976CA11;
+        bytes memory initCode = abi.encodePacked(type(TrailsRouter).creationCode, abi.encode(multicall3));
+        return Create2Utils.calculateCreate2Address(initCode, Create2Utils.standardSalt());
     }
 
     function expectedShimAddress() internal pure returns (address payable) {