Fix: align cancelAllPendingProposals() with specification

contracts/DualGovernance.sol

@@ -42,6 +42,8 @@ contract DualGovernance is IDualGovernance {
     // Events
     // ---
 
+    event CancelAllPendingProposalsSkipped();
+    event CancelAllPendingProposalsExecuted();
     event EscrowMasterCopyDeployed(address escrowMasterCopy);
     event ConfigProviderSet(IDualGovernanceConfigProvider newConfigProvider);
 
@@ -138,11 +140,27 @@ contract DualGovernance is IDualGovernance {
     }
 
     function cancelAllPendingProposals() external {
+        _stateMachine.activateNextState(_configProvider.getDualGovernanceConfig(), ESCROW_MASTER_COPY);
+
         Proposers.Proposer memory proposer = _proposers.getProposer(msg.sender);
         if (proposer.executor != TIMELOCK.getAdminExecutor()) {
             revert NotAdminProposer();
         }
+
+        State currentState = _stateMachine.getCurrentState();
+        if (currentState != State.VetoSignalling && currentState != State.VetoSignallingDeactivation) {
+            /// @dev Some proposer contracts, like Aragon Voting, may not support canceling decisions that have already
+            /// reached consensus. This could lead to a situation where a proposer’s cancelAllPendingProposals() call
+            /// becomes unexecutable if the Dual Governance state changes. However, it might become executable again if
+            /// the system state shifts back to VetoSignalling or VetoSignallingDeactivation.
+            /// To avoid such a scenario, an early return is used instead of a revert when proposals cannot be canceled
+            /// due to an unsuitable Dual Governance state.
+            emit CancelAllPendingProposalsSkipped();
+            return;
+        }
+
         TIMELOCK.cancelAllNonExecutedProposals();
+        emit CancelAllPendingProposalsExecuted();
     }
 
     function canSubmitProposal() public view returns (bool) {

test/mocks/StETHMock.sol

@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.26;
+
+import {ERC20Mock} from "@openzeppelin/contracts/mocks/token/ERC20Mock.sol";
+import {IStETH} from "contracts/interfaces/IStETH.sol";
+
+/* solhint-disable no-unused-vars,custom-errors */
+contract StETHMock is ERC20Mock, IStETH {
+    uint256 public __shareRate = 1 gwei;
+
+    constructor() {
+        /// @dev the total supply of the stETH always > 0
+        _mint(address(this), 100 wei);
+    }
+
+    function __setShareRate(uint256 newShareRate) public {
+        __shareRate = newShareRate;
+    }
+
+    function getSharesByPooledEth(uint256 ethAmount) external view returns (uint256) {
+        return ethAmount / __shareRate;
+    }
+
+    function getPooledEthByShares(uint256 sharesAmount) external view returns (uint256) {
+        return __shareRate * sharesAmount;
+    }
+
+    function transferShares(address to, uint256 sharesAmount) external {
+        transfer(to, sharesAmount * __shareRate);
+    }
+
+    function transferSharesFrom(
+        address _sender,
+        address _recipient,
+        uint256 _sharesAmount
+    ) external returns (uint256 tokensAmount) {
+        tokensAmount = _sharesAmount * __shareRate;
+        transferFrom(_sender, _recipient, tokensAmount);
+    }
+}

test/mocks/TimelockMock.sol

@@ -107,6 +107,10 @@ contract TimelockMock is ITimelock {
         revert("Not Implemented");
     }
 
+    function getProposalsCount() external view returns (uint256 count) {
+        return submittedProposals.length;
+    }
+
     function getAdminExecutor() external view returns (address) {
         return _ADMIN_EXECUTOR;
     }

test/mocks/WithdrawalQueueMock.sol

@@ -0,0 +1,135 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.26;
+
+// import {ERC721} from "@openzeppelin/contracts/token/ERC721/ERC721.sol"; /*, ERC721("test", "test")*/
+import {IWithdrawalQueue, WithdrawalRequestStatus} from "contracts/interfaces/IWithdrawalQueue.sol";
+
+/* solhint-disable no-unused-vars,custom-errors */
+contract WithdrawalQueueMock is IWithdrawalQueue {
+    uint256 private _lastRequestId;
+    uint256 private _lastFinalizedRequestId;
+    uint256 private _minStETHWithdrawalAmount;
+    uint256 private _maxStETHWithdrawalAmount;
+    uint256[] private _requestWithdrawalsResult;
+
+    constructor() {}
+
+    function MIN_STETH_WITHDRAWAL_AMOUNT() external view returns (uint256) {
+        return _minStETHWithdrawalAmount;
+    }
+
+    function MAX_STETH_WITHDRAWAL_AMOUNT() external view returns (uint256) {
+        return _maxStETHWithdrawalAmount;
+    }
+
+    function claimWithdrawals(uint256[] calldata requestIds, uint256[] calldata hints) external {
+        revert("Not Implemented");
+    }
+
+    function getLastRequestId() external view returns (uint256) {
+        return _lastRequestId;
+    }
+
+    function getLastFinalizedRequestId() external view returns (uint256) {
+        return _lastFinalizedRequestId;
+    }
+
+    function getWithdrawalStatus(uint256[] calldata _requestIds)
+        external
+        view
+        returns (WithdrawalRequestStatus[] memory statuses)
+    {
+        revert("Not Implemented");
+    }
+
+    /// @notice Returns amount of ether available for claim for each provided request id
+    /// @param _requestIds array of request ids
+    /// @param _hints checkpoint hints. can be found with `findCheckpointHints(_requestIds, 1, getLastCheckpointIndex())`
+    /// @return claimableEthValues amount of claimable ether for each request, amount is equal to 0 if request
+    ///  is not finalized or already claimed
+    function getClaimableEther(
+        uint256[] calldata _requestIds,
+        uint256[] calldata _hints
+    ) external view returns (uint256[] memory claimableEthValues) {
+        revert("Not Implemented");
+    }
+
+    function findCheckpointHints(
+        uint256[] calldata _requestIds,
+        uint256 _firstIndex,
+        uint256 _lastIndex
+    ) external view returns (uint256[] memory hintIds) {
+        revert("Not Implemented");
+    }
+
+    function getLastCheckpointIndex() external view returns (uint256) {
+        revert("Not Implemented");
+    }
+
+    function requestWithdrawals(
+        uint256[] calldata _amounts,
+        address _owner
+    ) external returns (uint256[] memory requestIds) {
+        return _requestWithdrawalsResult;
+    }
+
+    function balanceOf(address owner) external view returns (uint256 balance) {
+        revert("Not Implemented");
+    }
+
+    function ownerOf(uint256 tokenId) external view returns (address owner) {
+        revert("Not Implemented");
+    }
+
+    function safeTransferFrom(address from, address to, uint256 tokenId, bytes calldata data) external {
+        revert("Not Implemented");
+    }
+
+    function safeTransferFrom(address from, address to, uint256 tokenId) external {
+        revert("Not Implemented");
+    }
+
+    function transferFrom(address from, address to, uint256 tokenId) external {
+        revert("Not Implemented");
+    }
+
+    function approve(address to, uint256 tokenId) external {
+        revert("Not Implemented");
+    }
+
+    function setApprovalForAll(address operator, bool approved) external {
+        revert("Not Implemented");
+    }
+
+    function getApproved(uint256 tokenId) external view returns (address operator) {
+        revert("Not Implemented");
+    }
+
+    function isApprovedForAll(address owner, address operator) external view returns (bool) {
+        revert("Not Implemented");
+    }
+
+    function supportsInterface(bytes4 interfaceId) external view returns (bool) {
+        revert("Not Implemented");
+    }
+
+    function setLastRequestId(uint256 id) public {
+        _lastRequestId = id;
+    }
+
+    function setLastFinalizedRequestId(uint256 id) public {
+        _lastFinalizedRequestId = id;
+    }
+
+    function setMinStETHWithdrawalAmount(uint256 amount) public {
+        _minStETHWithdrawalAmount = amount;
+    }
+
+    function setMaxStETHWithdrawalAmount(uint256 amount) public {
+        _maxStETHWithdrawalAmount = amount;
+    }
+
+    function setRequestWithdrawalsResult(uint256[] memory requestIds) public {
+        _requestWithdrawalsResult = requestIds;
+    }
+}