Ran new build and squashed commits

contracts/base/GeneralMiddleware.sol

@@ -98,7 +98,7 @@ contract GeneralMiddleware is IbcMwUser, IbcMiddleware, IbcMwEventsEmitter, IbcM
         uint256 mwIndex,
         // bytes calldata appData,
         address[] calldata mwAddrs
-    ) external onlyIbcMw returns (AckPacket memory ackPacket) {
+    ) external onlyIbcMw returns (AckPacket memory ackPacket, bool skipAck) {
         // extra MW custom logic here to process packet, eg. emit MW events, mutate state, etc.
         // implementer can emit custom data fields suitable for their use cases.
         // Here we use MW_ID as the custom MW data field.
@@ -180,7 +180,7 @@ contract GeneralMiddleware is IbcMwUser, IbcMiddleware, IbcMwEventsEmitter, IbcM
         external
         override
         onlyIbcMw
-        returns (AckPacket memory ackPacket)
+        returns (AckPacket memory ackPacket, bool skipAck)
     {}
 
     function onUniversalAcknowledgement(bytes32 channelId, UniversalPacket memory packet, AckPacket calldata ack)

contracts/core/Dispatcher.sol

@@ -612,11 +612,15 @@ contract Dispatcher is Ownable2StepUpgradeable, UUPSUpgradeable, ReentrancyGuard
         }
 
         AckPacket memory ack;
+        bool skipAck;
         // Not timeout yet, then do normal handling
         (bool success, bytes memory data) =
             _callIfContract(receiver, abi.encodeWithSelector(IbcPacketReceiver.onRecvPacket.selector, packet));
         if (success) {
-            (ack) = abi.decode(data, (AckPacket));
+            (ack, skipAck) = abi.decode(data, (AckPacket, bool));
+            if (skipAck) {
+                return;
+            }
         } else {
             ack = AckPacket(false, data);
         }

contracts/core/UniversalChannelHandler.sol

@@ -136,7 +136,7 @@ contract UniversalChannelHandler is IbcReceiverBaseUpgradeable, FeeSender, UUPSU
         external
         override
         onlyIbcDispatcher
-        returns (AckPacket memory ackPacket)
+        returns (AckPacket memory ackPacket, bool skipAck)
     {
         UniversalPacket memory ucPacket = IbcUtils.fromUniversalPacketBytes(packet.data);
         // no other middleware stack registered for this packet. Deliver packet to dApp directly.

contracts/examples/Earth.sol

@@ -101,17 +101,18 @@ contract Earth is IbcUniversalPacketReceiverBase {
      * @param channelId The channel ID.
      * @param packet The universal packet.
      * @return ackPacket The acknowledgement packet.
+     * @return skipAck Whether to skip the writeAck event.
      * @dev It's recommended to always validate the authorized channel of any packet or channel using the
      * onlyAuthorizedChannel modifier.
      */
     function onRecvUniversalPacket(bytes32 channelId, UniversalPacket calldata packet)
         external
         onlyUCH
         onlyAuthorizedChannel(channelId)
-        returns (AckPacket memory ackPacket)
+        returns (AckPacket memory ackPacket, bool skipAck)
     {
         recvedPackets.push(UcPacketWithChannel(channelId, packet));
-        return this.generateAckPacket(channelId, IbcUtils.toAddress(packet.srcPortAddr), packet.appData);
+        return (this.generateAckPacket(channelId, IbcUtils.toAddress(packet.srcPortAddr), packet.appData), false);
     }
 
     /**

contracts/examples/Mars.sol

@@ -76,18 +76,19 @@ contract Mars is IbcReceiverBase, IbcReceiver, FeeSender {
      * @notice Callback for receiving a packet; triggered when a counterparty sends an an IBC packet
      * @param packet The IBC packet received
      * @return ackPacket The acknowledgement packet generated in response
+     * @return skipAck Whether to skip the writeAck event.
      * @dev Make sure to validate packet's source and destiation channels and ports.
      */
     function onRecvPacket(IbcPacket memory packet)
         external
         virtual
         onlyIbcDispatcher
-        returns (AckPacket memory ackPacket)
+        returns (AckPacket memory ackPacket, bool skipAck)
     {
         recvedPackets.push(packet);
 
         // solhint-disable-next-line quotes
-        return AckPacket(true, abi.encodePacked('{ "account": "account", "reply": "got the message" }'));
+        return (AckPacket(true, abi.encodePacked('{ "account": "account", "reply": "got the message" }')), false);
     }
 
     /**
@@ -243,10 +244,17 @@ contract RevertingStringMars is Mars {
     constructor(IbcDispatcher _dispatcher) Mars(_dispatcher) {}
 
     // solhint-disable-next-line
-    function onRecvPacket(IbcPacket memory) external view override onlyIbcDispatcher returns (AckPacket memory ack) {
+    function onRecvPacket(IbcPacket memory)
+        external
+        view
+        override
+        onlyIbcDispatcher
+        returns (AckPacket memory ack, bool skipAck)
+    {
         // solhint-disable-next-line
         require(false, "on recv packet is reverting");
         ack = AckPacket(false, "");
+        skipAck = false;
     }
 
     // solhint-disable-next-line
@@ -280,8 +288,15 @@ contract RevertingBytesMars is Mars {
 
     constructor(IbcDispatcher _dispatcher) Mars(_dispatcher) {}
 
-    function onRecvPacket(IbcPacket memory) external view override onlyIbcDispatcher returns (AckPacket memory ack) {
+    function onRecvPacket(IbcPacket memory)
+        external
+        view
+        override
+        onlyIbcDispatcher
+        returns (AckPacket memory ack, bool skipAck)
+    {
         ack = AckPacket(false, "");
+        skipAck = false;
         revert OnRecvPacketRevert();
     }
 
@@ -294,18 +309,33 @@ contract RevertingBytesMars is Mars {
 contract RevertingEmptyMars is Mars {
     constructor(IbcDispatcher _dispatcher) Mars(_dispatcher) {}
 
-    function onRecvPacket(IbcPacket memory) external view override onlyIbcDispatcher returns (AckPacket memory ack) {
+    function onRecvPacket(IbcPacket memory)
+        external
+        view
+        override
+        onlyIbcDispatcher
+        returns (AckPacket memory ack, bool skipAck)
+    {
         // solhint-disable-next-line
         require(false);
+        // Set values to avoid compiler warning
         ack = AckPacket(false, "");
+        skipAck = false;
     }
 }
 
 contract PanickingMars is Mars {
     constructor(IbcDispatcher _dispatcher) Mars(_dispatcher) {}
 
-    function onRecvPacket(IbcPacket memory) external view override onlyIbcDispatcher returns (AckPacket memory ack) {
+    function onRecvPacket(IbcPacket memory)
+        external
+        view
+        override
+        onlyIbcDispatcher
+        returns (AckPacket memory ack, bool skipAck)
+    {
         assert(false);
         ack = AckPacket(false, "");
+        skipAck = false;
     }
 }

contracts/examples/Pluto.sol

@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: Apache-2.0
+/*
+ * Copyright 2024, Polymer Labs
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+pragma solidity ^0.8.9;
+
+import {AckPacket} from "../libs/Ibc.sol";
+import {Mars} from "./Mars.sol";
+import {IbcPacket} from "../interfaces/IbcReceiver.sol";
+import {IbcDispatcher} from "../interfaces/IbcDispatcher.sol";
+
+/**
+ * @title Pluto
+ * @notice Pluto is a simple IBC receiver contract that receives packets without sending acks.
+ * @dev This contract is used for only testing IBC functionality and as an example for dapp developers
+ *  on how to integrate with the vibc protocol.
+ */
+contract Pluto is Mars {
+    constructor(IbcDispatcher _dispatcher) Mars(_dispatcher) {}
+
+    /**
+     * @notice Callback for receiving a packet; triggered when a counterparty sends an an IBC packet
+     * @param packet The IBC packet received
+     * @return ackPacket The acknowledgement packet generated in response
+     * @dev Make sure to validate packet's source and destiation channels and ports.
+     */
+    function onRecvPacket(IbcPacket memory packet)
+        external
+        override
+        onlyIbcDispatcher
+        returns (AckPacket memory ackPacket, bool skipAck)
+    {
+        recvedPackets.push(packet);
+
+        // solhint-disable-next-line quotes
+        return (AckPacket(true, abi.encodePacked('{ "account": "account", "reply": "got the message" }')), true);
+    }
+}

contracts/interfaces/IbcMiddleware.sol

@@ -73,7 +73,7 @@ interface IbcMwPacketReceiver {
         // Each mw in the stack must increment mwIndex by 1 before calling the next MW.
         uint256 mwIndex,
         address[] calldata mwAddrs
-    ) external returns (AckPacket memory ackPacket);
+    ) external returns (AckPacket memory ackPacket, bool skipAck);
 
     function onRecvMWAck(
         bytes32 channelId,
@@ -103,7 +103,7 @@ interface IbcUniversalPacketReceiver {
 
     function onRecvUniversalPacket(bytes32 channelId, UniversalPacket calldata ucPacket)
         external
-        returns (AckPacket memory ackPacket);
+        returns (AckPacket memory ackPacket, bool skipAck);
 
     function onUniversalAcknowledgement(bytes32 channelId, UniversalPacket memory packet, AckPacket calldata ack)
         external;

contracts/interfaces/IbcReceiver.sol

@@ -81,9 +81,10 @@ interface IbcPacketReceiver {
      * @notice Callback for receiving a packet; triggered when a counterparty sends an an IBC packet
      * @param packet The IBC packet received
      * @return ackPacket The acknowledgement packet generated in response
+     * @return skipAck Whether to skip sending an acknowledgement packet
      * @dev Make sure to validate packet's source and destiation channels and ports.
      */
-    function onRecvPacket(IbcPacket calldata packet) external returns (AckPacket memory ackPacket);
+    function onRecvPacket(IbcPacket calldata packet) external returns (AckPacket memory ackPacket, bool skipAck);
 
     /**
      * @notice Callback for acknowledging a packet; triggered on reciept of an IBC packet by the counterparty

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@open-ibc/vibc-core-smart-contracts",
-  "version": "3.1.0",
+  "version": "4.0.0",
   "main": "dist/index.js",
   "bin": {
     "verify-vibc-core-smart-contracts": "./dist/scripts/verify-contract-script.js",

src/evm/contracts/Earth.ts

@@ -301,7 +301,12 @@ export interface Earth extends BaseContract {
 
   onRecvUniversalPacket: TypedContractMethod<
     [channelId: BytesLike, packet: UniversalPacketStruct],
-    [AckPacketStructOutput],
+    [
+      [AckPacketStructOutput, boolean] & {
+        ackPacket: AckPacketStructOutput;
+        skipAck: boolean;
+      }
+    ],
     "nonpayable"
   >;
 
@@ -413,7 +418,12 @@ export interface Earth extends BaseContract {
     nameOrSignature: "onRecvUniversalPacket"
   ): TypedContractMethod<
     [channelId: BytesLike, packet: UniversalPacketStruct],
-    [AckPacketStructOutput],
+    [
+      [AckPacketStructOutput, boolean] & {
+        ackPacket: AckPacketStructOutput;
+        skipAck: boolean;
+      }
+    ],
     "nonpayable"
   >;
   getFunction(

src/evm/contracts/IUniversalChannelHandler.ts

@@ -326,7 +326,12 @@ export interface IUniversalChannelHandler extends BaseContract {
 
   onRecvPacket: TypedContractMethod<
     [packet: IbcPacketStruct],
-    [AckPacketStructOutput],
+    [
+      [AckPacketStructOutput, boolean] & {
+        ackPacket: AckPacketStructOutput;
+        skipAck: boolean;
+      }
+    ],
     "nonpayable"
   >;
 
@@ -450,7 +455,12 @@ export interface IUniversalChannelHandler extends BaseContract {
     nameOrSignature: "onRecvPacket"
   ): TypedContractMethod<
     [packet: IbcPacketStruct],
-    [AckPacketStructOutput],
+    [
+      [AckPacketStructOutput, boolean] & {
+        ackPacket: AckPacketStructOutput;
+        skipAck: boolean;
+      }
+    ],
     "nonpayable"
   >;
   getFunction(

src/evm/contracts/Mars.sol/Mars.ts

@@ -404,7 +404,12 @@ export interface Mars extends BaseContract {
 
   onRecvPacket: TypedContractMethod<
     [packet: IbcPacketStruct],
-    [AckPacketStructOutput],
+    [
+      [AckPacketStructOutput, boolean] & {
+        ackPacket: AckPacketStructOutput;
+        skipAck: boolean;
+      }
+    ],
     "nonpayable"
   >;
 
@@ -590,7 +595,12 @@ export interface Mars extends BaseContract {
     nameOrSignature: "onRecvPacket"
   ): TypedContractMethod<
     [packet: IbcPacketStruct],
-    [AckPacketStructOutput],
+    [
+      [AckPacketStructOutput, boolean] & {
+        ackPacket: AckPacketStructOutput;
+        skipAck: boolean;
+      }
+    ],
     "nonpayable"
   >;
   getFunction(

src/evm/contracts/Mars.sol/PanickingMars.ts

@@ -404,7 +404,12 @@ export interface PanickingMars extends BaseContract {
 
   onRecvPacket: TypedContractMethod<
     [arg0: IbcPacketStruct],
-    [AckPacketStructOutput],
+    [
+      [AckPacketStructOutput, boolean] & {
+        ack: AckPacketStructOutput;
+        skipAck: boolean;
+      }
+    ],
     "view"
   >;
 
@@ -590,7 +595,12 @@ export interface PanickingMars extends BaseContract {
     nameOrSignature: "onRecvPacket"
   ): TypedContractMethod<
     [arg0: IbcPacketStruct],
-    [AckPacketStructOutput],
+    [
+      [AckPacketStructOutput, boolean] & {
+        ack: AckPacketStructOutput;
+        skipAck: boolean;
+      }
+    ],
     "view"
   >;
   getFunction(

src/evm/contracts/Mars.sol/RevertingBytesMars.ts

@@ -404,7 +404,12 @@ export interface RevertingBytesMars extends BaseContract {
 
   onRecvPacket: TypedContractMethod<
     [arg0: IbcPacketStruct],
-    [AckPacketStructOutput],
+    [
+      [AckPacketStructOutput, boolean] & {
+        ack: AckPacketStructOutput;
+        skipAck: boolean;
+      }
+    ],
     "view"
   >;
 
@@ -586,7 +591,12 @@ export interface RevertingBytesMars extends BaseContract {
     nameOrSignature: "onRecvPacket"
   ): TypedContractMethod<
     [arg0: IbcPacketStruct],
-    [AckPacketStructOutput],
+    [
+      [AckPacketStructOutput, boolean] & {
+        ack: AckPacketStructOutput;
+        skipAck: boolean;
+      }
+    ],
     "view"
   >;
   getFunction(