Test rollback

contracts/blade/Gateway.sol

@@ -69,7 +69,7 @@ contract Gateway is ValidatorSetStorage, IGateway {
     function receiveBatch(
         BridgeMessage[] calldata batchMessages,
         SignedBridgeMessageBatch calldata signedBridgeBatch
-    ) external {
+    ) external virtual {
         if (signedBridgeBatch.isRollback) {
             _verifyRollbackBatch(batchMessages);
         } else {
@@ -125,6 +125,7 @@ contract Gateway is ValidatorSetStorage, IGateway {
      * @notice Internal function that verifies the batch
      * @param batch batch to verify
      */
+    // slither-disable-start dead-code
     function _verifyBatch(BridgeMessage[] calldata batch) private view {
         require(batch.length > 0, "EMPTY_BATCH");
 
@@ -141,7 +142,9 @@ contract Gateway is ValidatorSetStorage, IGateway {
         }
     }
 
-    function _verifyRollbackBatch(BridgeMessage[] calldata batch) private view {
+    // slither-disable-end dead-code
+
+    function _verifyRollbackBatch(BridgeMessage[] calldata batch) internal view {
         require(batch.length > 0, "EMPTY_BATCH");
 
         uint256 sourceChainId = block.chainid;
@@ -157,6 +160,7 @@ contract Gateway is ValidatorSetStorage, IGateway {
         }
     }
 
+    // slither-disable-start dead-code
     function _executeBridgeMessage(BridgeMessage calldata message) private {
         require(!processedEvents[message.id], "DestinationGateway: BRIDGE_MESSAGE_IS_ALREADY_PROCESSED");
         // revert transaction if client has added flag, or receiver has no code
@@ -181,7 +185,9 @@ contract Gateway is ValidatorSetStorage, IGateway {
         emit BridgeMessageResult(message.id, success, message.sourceChainId, message.destinationChainId, returnData);
     }
 
-    function _executeRollbackBridgeMessage(BridgeMessage calldata message) private {
+    // slither-disable-end dead-code
+
+    function _executeRollbackBridgeMessage(BridgeMessage calldata message) internal {
         require(
             !processedEventsRollback[message.id],
             "DestinationGateway: ROLLBACK_BRIDGE_MESSAGE_IS_ALREADY_PROCESSED"

contracts/blade/TestRollbackGateway.sol

@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.19;
+
+import "./Gateway.sol";
+
+contract TestRollbackGateway is Gateway {
+    /**
+     * @notice Test function to generate error for testing rollback
+     * @param message Error message
+     */
+    error TestRollbackError(string message);
+
+    /**
+     * @notice receives the batch of messages and executes them
+     * @param batchMessages batch of messages
+     */
+    // slither-disable-next-line protected-vars
+    function receiveBatch(
+        BridgeMessage[] calldata batchMessages,
+        SignedBridgeMessageBatch calldata signedBridgeBatch
+    ) external override {
+        if (!signedBridgeBatch.isRollback) {
+            revert TestRollbackError("TESTING BATCH");
+        }
+
+        _verifyRollbackBatch(batchMessages);
+
+        bytes memory hash = abi.encode(
+            keccak256(
+                abi.encode(
+                    calculateMerkleRoot(batchMessages),
+                    signedBridgeBatch.startId,
+                    signedBridgeBatch.endId,
+                    signedBridgeBatch.sourceChainId,
+                    signedBridgeBatch.destinationChainId,
+                    signedBridgeBatch.threshold,
+                    signedBridgeBatch.isRollback
+                )
+            )
+        );
+
+        verifySignature(bls.hashToPoint(DOMAIN_BRIDGE, hash), signedBridgeBatch.signature, signedBridgeBatch.bitmap);
+
+        uint256 length = batchMessages.length;
+
+        for (uint256 i = 0; i < length; ) {
+            _executeRollbackBridgeMessage(batchMessages[i]);
+
+            unchecked {
+                ++i;
+            }
+        }
+
+        // slither-disable-next-line reentrancy-events
+        emit BridgeBatchResult(
+            signedBridgeBatch.startId,
+            signedBridgeBatch.endId,
+            signedBridgeBatch.sourceChainId,
+            signedBridgeBatch.destinationChainId,
+            signedBridgeBatch.isRollback
+        );
+    }
+}