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Author: ernestognw

contracts/crosschain/axelar/AxelarGatewayBase.sol

@@ -42,7 +42,7 @@ abstract contract AxelarGatewayBase is Ownable {
         require(bytes(output).length > 0, UnsupportedChain(input));
     }
 
-    /// @dev Returns the CAIP-10 account address of the remote gateway for a given CAIP-2 chain identifier.
+    /// @dev Returns the address string of the remote gateway for a given CAIP-2 chain identifier.
     function getRemoteGateway(string memory caip2) public view virtual returns (string memory remoteGateway) {
         remoteGateway = _remoteGateways[caip2];
         require(bytes(remoteGateway).length > 0, UnsupportedChain(caip2));
@@ -56,7 +56,7 @@ abstract contract AxelarGatewayBase is Ownable {
         emit RegisteredChainEquivalence(caip2, axelarSupported);
     }
 
-    /// @dev Registers the CAIP-10 account address of the remote gateway for a given CAIP-2 chain identifier.
+    /// @dev Registers the address string of the remote gateway for a given CAIP-2 chain identifier.
     function registerRemoteGateway(string calldata caip2, string calldata remoteGateway) public virtual onlyOwner {
         require(bytes(_remoteGateways[caip2]).length == 0, RemoteGatewayAlreadyRegistered(caip2));
         _remoteGateways[caip2] = remoteGateway;

contracts/crosschain/axelar/AxelarGatewayDestination.sol

@@ -21,11 +21,15 @@ abstract contract AxelarGatewayDestination is IERC7786GatewayDestinationPassive,
     error InvalidOriginGateway(string sourceChain, string axelarSourceAddress);
     error ReceiverExecutionFailed();
 
-    /// @dev Sets a message as executed so it can't be executed again. Should be called by the receiver contract.
+    /**
+     * @dev Sets a message as executed so it can't be executed again. Should be called by the receiver contract.
+     * @param sourceChain {CAIP2} chain identifier
+     * @param sender {CAIP10} account address (does not include the chain identifier)
+     */
     function setMessageExecuted(
         bytes calldata messageKey,
-        string calldata sourceChain, // CAIP-2 chain identifier
-        string calldata sender, // CAIP-10 account address (does not include the chain identifier)
+        string calldata sourceChain,
+        string calldata sender,
         bytes calldata payload,
         bytes[] calldata attributes
     ) external {

contracts/crosschain/axelar/AxelarGatewayDuplex.sol

@@ -7,7 +7,12 @@ import {AxelarGatewayBase, IAxelarGateway} from "./AxelarGatewayBase.sol";
 import {AxelarGatewayDestination, AxelarExecutable} from "./AxelarGatewayDestination.sol";
 import {AxelarGatewaySource} from "./AxelarGatewaySource.sol";
 
+/**
+ * @dev A contract that combines the functionality of both the source and destination gateway
+ * adapters for the Axelar Network. Allowing to either send or receive messages across chains.
+ */
 contract AxelarGatewayDuplex is AxelarGatewaySource, AxelarGatewayDestination {
+    /// @dev Initializes the contract with the Axelar gateway and the initial owner.
     constructor(
         IAxelarGateway gateway,
         address initialOwner

contracts/crosschain/axelar/AxelarGatewaySource.sol

@@ -30,7 +30,7 @@ abstract contract AxelarGatewaySource is IERC7786GatewaySource, AxelarGatewayBas
         string calldata receiver, // CAIP-10 account address (does not include the chain identifier)
         bytes calldata payload,
         bytes[] calldata attributes
-    ) external payable returns (bytes32) {
+    ) external payable returns (bytes32 outboxId) {
         require(msg.value == 0, SendingValueNotSupported());
         if (attributes.length > 0)
             revert UnsupportedAttribute(attributes[0].length < 0x04 ? bytes4(0) : bytes4(attributes[0][0:4]));
@@ -40,8 +40,9 @@ abstract contract AxelarGatewaySource is IERC7786GatewaySource, AxelarGatewayBas
         bytes memory adapterPayload = abi.encode(sender, receiver, payload, attributes);
 
         // Emit event
+        outboxId = bytes32(0); // Explicitly set to 0
         emit MessagePosted(
-            0,
+            outboxId,
             CAIP10.format(CAIP2.local(), sender),
             CAIP10.format(destinationChain, receiver),
             payload,
@@ -53,6 +54,6 @@ abstract contract AxelarGatewaySource is IERC7786GatewaySource, AxelarGatewayBas
         string memory remoteGateway = getRemoteGateway(destinationChain);
         localGateway.callContract(axelarDestination, remoteGateway, adapterPayload);
 
-        return 0;
+        return outboxId;
     }
 }

contracts/crosschain/interfaces/draft-IERC7786.sol

@@ -30,15 +30,17 @@ interface IERC7786GatewaySource {
      * @dev Endpoint for creating a new message. If the message requires further (gateway specific) processing before
      * it can be sent to the destination chain, then a non-zero `outboxId` must be returned. Otherwise, the
      * message MUST be sent and this function must return 0.
+     * @param destinationChain {CAIP2} chain identifier
+     * @param receiver {CAIP10} account address (does not include the chain identifier)
      *
-     * * MUST emit a {MessageCreated} event.
+     * * MUST emit a {MessagePosted} event.
      *
      * If any of the `attributes` is not supported, this function SHOULD revert with an {UnsupportedAttribute} error.
      * Other errors SHOULD revert with errors not specified in ERC-7786.
      */
     function sendMessage(
-        string calldata destinationChain, // CAIP-2 chain identifier
-        string calldata receiver, // CAIP-10 account address (does not include the chain identifier)
+        string calldata destinationChain,
+        string calldata receiver,
         bytes calldata payload,
         bytes[] calldata attributes
     ) external payable returns (bytes32 outboxId);
@@ -56,14 +58,16 @@ interface IERC7786GatewayDestinationPassive {
      * @dev Endpoint for checking the validity of a message that is being relayed in passive mode. The message
      * receiver is implicitly the caller of this method, which guarantees that no one but the receiver can
      * "consume" the message. This function MUST implement replay protection, meaning that if called multiple time
-     * for same message, all but the first calls MUST revert.
+     * for same message, all but the first calls MUST revert.'
+     * @param sourceChain {CAIP2} chain identifier
+     * @param sender {CAIP10} account address (does not include the chain identifier)
      *
      * NOTE: implementing this interface is OPTIONAL. Some destination gateway MAY only support active mode.
      */
     function setMessageExecuted(
         bytes calldata messageKey,
-        string calldata sourceChain, // CAIP-2 chain identifier
-        string calldata sender, // CAIP-10 account address (does not include the chain identifier)
+        string calldata sourceChain,
+        string calldata sender,
         bytes calldata payload,
         bytes[] calldata attributes
     ) external;
@@ -77,14 +81,16 @@ interface IERC7786GatewayDestinationPassive {
 interface IERC7786Receiver {
     /**
      * @dev Endpoint for receiving cross-chain message.
+     * @param sourceChain {CAIP2} chain identifier
+     * @param sender {CAIP10} account address (does not include the chain identifier)
      *
      * This function may be called directly by the gateway (active mode) or by a third party (passive mode).
      */
     function executeMessage(
         address gateway,
         bytes calldata gatewayMessageKey,
-        string calldata sourceChain, // CAIP-2 chain identifier
-        string calldata sender, // CAIP-10 account address (does not include the chain identifier)
+        string calldata sourceChain,
+        string calldata sender,
         bytes calldata payload,
         bytes[] calldata attributes
     ) external payable returns (bytes4);

contracts/crosschain/utils/draft-ERC7786Receiver.sol

@@ -24,8 +24,8 @@ abstract contract ERC7786Receiver is IERC7786Receiver {
     function executeMessage(
         address gateway,
         bytes calldata gatewayMessageKey,
-        string calldata source,
-        string calldata sender,
+        string calldata sourceChain, // CAIP-2 chain identifier
+        string calldata sender, // CAIP-10 account address (does not include the chain identifier)
         bytes calldata payload,
         bytes[] calldata attributes
     ) public payable virtual returns (bytes4) {
@@ -37,15 +37,15 @@ abstract contract ERC7786Receiver is IERC7786Receiver {
             require(msg.value == 0, ERC7786ReceivePassiveModeValue());
             IERC7786GatewayDestinationPassive(gateway).setMessageExecuted(
                 gatewayMessageKey,
-                source,
+                sourceChain,
                 sender,
                 payload,
                 attributes
             );
         } else {
             revert ERC7786ReceiverInvalidGateway(gateway);
         }
-        _processMessage(gateway, source, sender, payload, attributes);
+        _processMessage(gateway, sourceChain, sender, payload, attributes);
         return IERC7786Receiver.executeMessage.selector;
     }
 
@@ -55,7 +55,7 @@ abstract contract ERC7786Receiver is IERC7786Receiver {
     /// @dev Virtual function that should contain the logic to execute when a cross-chain message is received.
     function _processMessage(
         address gateway,
-        string calldata source,
+        string calldata sourceChain,
         string calldata sender,
         bytes calldata payload,
         bytes[] calldata attributes