chore: add virtual flag to overridable functions

.changeset/chatty-sloths-fetch.md

@@ -0,0 +1,5 @@
+---
+"@layerzerolabs/oft-evm-upgradeable": patch
+---
+
+Add virtual keyword to overridable functions

packages/oft-evm-upgradeable/contracts/oft/FeeUpgradeable.sol

@@ -39,7 +39,7 @@ abstract contract FeeUpgradeable is IFee, Initializable, OwnableUpgradeable {
     /**
      * @dev Sets the default fee basis points (BPS) for all destinations.
      */
-    function setDefaultFeeBps(uint16 _feeBps) external onlyOwner {
+    function setDefaultFeeBps(uint16 _feeBps) external virtual onlyOwner {
         if (_feeBps > BPS_DENOMINATOR) revert IFee.InvalidBps();
         FeeStorage storage $ = _getFeeStorage();
         $.defaultFeeBps = _feeBps;
@@ -49,7 +49,7 @@ abstract contract FeeUpgradeable is IFee, Initializable, OwnableUpgradeable {
     /**
      * @dev Sets the fee basis points (BPS) for a specific destination LayerZero EndpointV2 ID.
      */
-    function setFeeBps(uint32 _dstEid, uint16 _feeBps, bool _enabled) external onlyOwner {
+    function setFeeBps(uint32 _dstEid, uint16 _feeBps, bool _enabled) external virtual onlyOwner {
         if (_feeBps > BPS_DENOMINATOR) revert IFee.InvalidBps();
         FeeStorage storage $ = _getFeeStorage();
         $.feeBps[_dstEid] = FeeConfig(_feeBps, _enabled);
@@ -65,7 +65,7 @@ abstract contract FeeUpgradeable is IFee, Initializable, OwnableUpgradeable {
         return bps == 0 ? 0 : (_amount * bps) / BPS_DENOMINATOR;
     }
 
-    function _getFeeBps(uint32 _dstEid) internal view returns (uint16) {
+    function _getFeeBps(uint32 _dstEid) internal view virtual returns (uint16) {
         FeeStorage storage $ = _getFeeStorage();
         FeeConfig memory config = $.feeBps[_dstEid];
         return config.enabled ? config.feeBps : $.defaultFeeBps;

packages/oft-evm-upgradeable/contracts/oft/NativeOFTAdapterUpgradeable.sol

@@ -45,7 +45,7 @@ abstract contract NativeOFTAdapterUpgradeable is OFTCoreUpgradeable {
      * @dev Returns the address of the native token
      * @return The address of the native token.
      */
-    function token() public pure returns (address) {
+    function token() public pure virtual returns (address) {
         return address(0);
     }
 
@@ -135,7 +135,7 @@ abstract contract NativeOFTAdapterUpgradeable is OFTCoreUpgradeable {
      * @param _nativeFee The native fee to be paid.
      * @return nativeFee The amount of native currency paid.
      */
-    function _payNative(uint256 _nativeFee) internal pure override returns (uint256 nativeFee) {
+    function _payNative(uint256 _nativeFee) internal pure virtual override returns (uint256 nativeFee) {
         return _nativeFee;
     }
 }

packages/oft-evm-upgradeable/contracts/oft/OFTAdapterFeeUpgradeable.sol

@@ -36,7 +36,7 @@ abstract contract OFTAdapterFeeUpgradeable is OFTAdapterUpgradeable, FeeUpgradea
         }
     }
 
-    function feeBalance() public view returns (uint256) {
+    function feeBalance() public view virtual returns (uint256) {
         OFTAdapterFeeStorage storage $ = _getOFTAdapterFeeStorage();
         return $.feeBalance;
     }
@@ -72,7 +72,7 @@ abstract contract OFTAdapterFeeUpgradeable is OFTAdapterUpgradeable, FeeUpgradea
      * @notice Withdraws accumulated fees to a specified address.
      * @param _to The address to which the fees will be withdrawn.
      */
-    function withdrawFees(address _to) external onlyOwner {
+    function withdrawFees(address _to) external virtual onlyOwner {
         // @dev doesn't allow owner to pull from the locked assets of the contract,
         // only from accumulated fees
         OFTAdapterFeeStorage storage $ = _getOFTAdapterFeeStorage();

packages/oft-evm-upgradeable/contracts/oft/OFTAdapterUpgradeable.sol

@@ -55,7 +55,7 @@ abstract contract OFTAdapterUpgradeable is OFTCoreUpgradeable {
      *
      * @dev In the case of OFTAdapter, address(this) and erc20 are NOT the same contract.
      */
-    function token() public view returns (address) {
+    function token() public view virtual returns (address) {
         return address(innerToken);
     }
 

packages/oft-evm-upgradeable/contracts/oft/OFTCoreUpgradeable.sol

@@ -103,7 +103,7 @@ abstract contract OFTCoreUpgradeable is
 
     function __OFTCore_init_unchained() internal onlyInitializing {}
 
-    function msgInspector() public view returns (address) {
+    function msgInspector() public view virtual returns (address) {
         OFTCoreStorage storage $ = _getOFTCoreStorage();
         return $.msgInspector;
     }

packages/oft-evm-upgradeable/contracts/oft/OFTFeeUpgradeable.sol

@@ -24,7 +24,7 @@ abstract contract OFTFeeUpgradeable is OFTUpgradeable, FeeUpgradeable {
         }
     }
 
-    function feeBalance() public view returns (uint256) {
+    function feeBalance() public view virtual returns (uint256) {
         OFTFeeStorage storage $ = _getOFTFeeStorage();
         return $.feeBalance;
     }
@@ -121,7 +121,7 @@ abstract contract OFTFeeUpgradeable is OFTUpgradeable, FeeUpgradeable {
      * @notice Withdraws accumulated fees to a specified address.
      * @param _to The address to which the fees will be withdrawn.
      */
-    function withdrawFees(address _to) external onlyOwner {
+    function withdrawFees(address _to) external virtual onlyOwner {
         OFTFeeStorage storage $ = _getOFTFeeStorage();
         uint256 balance = $.feeBalance;
         if (balance == 0) revert NoFeesToWithdraw();

packages/oft-evm-upgradeable/contracts/oft/OFTUpgradeable.sol

@@ -39,7 +39,7 @@ abstract contract OFTUpgradeable is OFTCoreUpgradeable, ERC20Upgradeable {
      *
      * @dev In the case of OFT, address(this) and erc20 are the same contract.
      */
-    function token() public view returns (address) {
+    function token() public view virtual returns (address) {
         return address(this);
     }