fix: skip already queued up tx

src/RoboSaverVirtualModule.sol

@@ -537,8 +537,13 @@ contract RoboSaverVirtualModule is
     /// @param _target The address of the target of the transaction
     /// @param _payload The payload of the transaction
     function _queueTx(address _target, bytes memory _payload) internal {
-        /// @dev since all actions go through multicall3, operation is set to 1 (DelegateCall)
-        delayModule.execTransactionFromModule(_target, 0, _payload, 1);
+        /// @dev the newest action is leading; if we already have a transaction queued up we should skip it
+        if (queuedTx.nonce != 0) {
+            delayModule.setTxNonce(queuedTx.nonce);
+            delete queuedTx;
+        }
+
+        delayModule.execTransactionFromModule(_target, 0, _payload, OPERATION_DELEGATECALL);
         uint256 cachedQueueNonce = delayModule.queueNonce();
         queuedTx = VirtualModule.QueuedTx(cachedQueueNonce, _target, _payload);
 

src/abstracts/RoboSaverConstants.sol

@@ -9,8 +9,8 @@ import "@balancer-v2/interfaces/contracts/vault/IVault.sol";
 import "@balancer-v2/interfaces/contracts/solidity-utils/misc/IERC4626.sol";
 
 abstract contract RoboSaverConstants {
+    uint8 constant OPERATION_DELEGATECALL = 1;
     uint16 constant MAX_BPS = 10_000;
-
     uint256 constant EURE_TOKEN_BPT_INDEX = 2;
     uint256 constant EURE_TOKEN_BPT_INDEX_USER = 1;
     uint256 constant MODULE_PAGE_SIZE = 1;

test/regression/CornerCaseV0_1_0Test.t.sol

@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: GPL-3.0-only
+pragma solidity ^0.8.25;
+
+import {BaseFixture} from "../BaseFixture.sol";
+
+import {VirtualModule} from "../../src/types/DataTypes.sol";
+
+/// @notice This file is for testing the corner cases that were faced during v0.1.0 tests-run
+///         and face minor challenges which should be always fixed and gracefully handled on `>v0.1.0`
+contract CornerCaseV0_1_0Test is BaseFixture {
+    function test_DepositAndShutdownBlockage() public {
+        // 1. encounter condition where naturally a deposit is being queued
+        _incomingEure(1_000e18);
+        uint256 surplus = roboModule.surplus();
+        assertGt(surplus, 0);
+
+        _upkeepAndAssertPayload(abi.encode(VirtualModule.PoolAction.DEPOSIT, surplus));
+
+        (uint256 nonceDepositTx,, bytes memory payloadDepositTx) = roboModule.queuedTx();
+        assertEq(nonceDepositTx, 1);
+
+        // 2. admin of the virtual module decides to `shutdown()` while initial queue tx is on cooldown phase still
+        vm.prank(roboModule.CARD());
+        roboModule.shutdown();
+
+        // 3. Internal payload should not have being override, otherwise initial deposit never can be executed
+        (uint256 nonceShutdownTx,, bytes memory payloadShutdownTx) = roboModule.queuedTx();
+
+        // @note if it not identical a blockage will be suffer and force to wait for tx expiration
+        assertEq(nonceDepositTx, nonceShutdownTx);
+        assertEq(payloadDepositTx, payloadShutdownTx);
+    }
+}