Merge pull request #17 from morpho-org/review/merlin-optimism

Review/merlin optimism

src/ERC20DelegatesUpgradeable.sol

@@ -12,7 +12,7 @@ import {EIP712Upgradeable} from
 import {Initializable} from "lib/openzeppelin-contracts-upgradeable/contracts/proxy/utils/Initializable.sol";
 
 /// @title ERC20DelegatesUpgradeable
-/// @author Morpho Labs
+/// @author Morpho Association
 /// @custom:contact security@morpho.org
 /// @dev Extension of ERC20 to support token delegation.
 ///

src/MorphoToken.sol

@@ -12,7 +12,7 @@ import {
 import {UUPSUpgradeable} from "lib/openzeppelin-contracts-upgradeable/contracts/proxy/utils/UUPSUpgradeable.sol";
 
 /// @title MorphoToken
-/// @author Morpho Labs
+/// @author Morpho Association
 /// @custom:contact security@morpho.org
 /// @notice The MORPHO Token contract.
 contract MorphoToken is ERC20DelegatesUpgradeable, ERC20PermitUpgradeable, Ownable2StepUpgradeable, UUPSUpgradeable {

src/MorphoTokenOptimism.sol

@@ -10,7 +10,7 @@ import {ERC20PermitUpgradeable} from
 import {UUPSUpgradeable} from "lib/openzeppelin-contracts-upgradeable/contracts/proxy/utils/UUPSUpgradeable.sol";
 
 /// @title MorphoToken
-/// @author Morpho Labs
+/// @author Morpho Association
 /// @custom:contact security@morpho.org
 /// @notice The MORPHO Token contract for Optimism networks.
 contract MorphoTokenOptimism is
@@ -27,11 +27,6 @@ contract MorphoTokenOptimism is
     /// @dev The symbol of the token.
     string internal constant SYMBOL = "MORPHO";
 
-    /* ERRORS */
-
-    /// @notice Reverts if the address is the zero address.
-    error ZeroAddress();
-
     /* PUBLIC */
 
     /// @notice Initializes the contract.

src/OptimismMintableERC20Upgradeable.sol

@@ -1,124 +1,118 @@
 // SPDX-License-Identifier: MIT
 pragma solidity 0.8.27;
 
-import {ERC20Upgradeable} from "lib/openzeppelin-contracts-upgradeable/contracts/token/ERC20/ERC20Upgradeable.sol";
+import {IOptimismMintableERC20} from "./interfaces/IOptimismMintableERC20.sol";
 import {IERC165} from "@openzeppelin/contracts/utils/introspection/IERC165.sol";
-import {ILegacyMintableERC20, IOptimismMintableERC20} from "./interfaces/IOptimismMintableERC20.sol";
 import {Initializable} from "lib/openzeppelin-contracts-upgradeable/contracts/proxy/utils/Initializable.sol";
+import {ERC20Upgradeable} from "lib/openzeppelin-contracts-upgradeable/contracts/token/ERC20/ERC20Upgradeable.sol";
 
 /// @title OptimismMintableERC20
-/// @author Morpho Labs
+/// @author Morpho Association
 /// @custom:contact security@morpho.org
 /// @dev Extension of ERC20 to Optimism network deployment.
 ///
 /// This extension allows the StandardBridge contracts to mint and burn tokens. This makes it possible to use an
 /// OptimismMintablERC20 as the L2 representation of an L1 token, or vice-versa. Designed to be backwards compatible
 /// with the older StandardL2ERC20 token which was only meant for use on L2.
-contract OptimismMintableERC20Upgradeable is
-    Initializable,
-    IOptimismMintableERC20,
-    ILegacyMintableERC20,
-    ERC20Upgradeable
-{
+contract OptimismMintableERC20Upgradeable is Initializable, IOptimismMintableERC20, ERC20Upgradeable {
+    /* CONSTANTS */
+
     // keccak256(abi.encode(uint256(keccak256("morpho.storage.OptimismMintableERC20")) - 1)) & ~bytes32(uint256(0xff))
     bytes32 private constant OptimismMintableERC20StorageLocation =
         0x6fd4c0a11d0843c68c809f0a5f29b102d54bc08a251c384d9ad17600bfa05d00;
 
     /* STRUCTS */
 
-    /// @custom:storage-location erc7201:morpho.storage.ERC20Delegates
+    /// @custom:storage-location erc7201:morpho.storage.OptimismMintableERC20
     struct OptimismMintableERC20Storage {
-        address _REMOTE_TOKEN;
-        address _BRIDGE;
+        address _remoteToken;
+        address _bridge;
     }
 
-    ///@dev Emitted whenever tokens are minted for an account.
+    /* EVENTS */
+
+    /// @dev Emitted whenever tokens are minted for an account.
     event Mint(address indexed account, uint256 amount);
 
-    ///@dev Emitted whenever tokens are burned from an account.
+    /// @dev Emitted whenever tokens are burned from an account.
     event Burn(address indexed account, uint256 amount);
 
-    ///@dev A modifier that only allows the bridge to call
+    /* ERRORS */
+
+    /// @notice Reverts if the address is the zero address.
+    error ZeroAddress();
+
+    /// @notice Reverts if the caller is not the bridge.
+    error NotBridge(address caller);
+
+    /* MODIFIERS */
+
+    /// @dev A modifier that only allows the bridge to call.
     modifier onlyBridge() {
         OptimismMintableERC20Storage storage $ = _getOptimismMintableERC20Storage();
-        require(_msgSender() == $._BRIDGE, "OptimismMintableERC20: only bridge can mint and burn");
+        require(_msgSender() == $._bridge, NotBridge(_msgSender()));
         _;
     }
 
-    ///@dev Sets the values for {remoteToken} and {bridge}.
-    ///@dev All two of these values are immutable: they can only be set once during initialization.
+    /* INITIALIZER */
+
+    /// @dev Sets the values for {remoteToken} and {bridge}.
+    /// @dev All two of these values are immutable: they can only be set once during initialization.
     function __OptimismMintableERC20_init(address remoteToken_, address bridge_) internal onlyInitializing {
         __OptimismMintableERC20_init_unchained(remoteToken_, bridge_);
     }
 
     function __OptimismMintableERC20_init_unchained(address remoteToken_, address bridge_) internal onlyInitializing {
+        require(remoteToken_ != address(0), ZeroAddress());
+        require(bridge_ != address(0), ZeroAddress());
+
         OptimismMintableERC20Storage storage $ = _getOptimismMintableERC20Storage();
-        $._REMOTE_TOKEN = remoteToken_;
-        $._BRIDGE = bridge_;
+        $._remoteToken = remoteToken_;
+        $._bridge = bridge_;
     }
 
-    ///@dev Allows the StandardBridge on this network to mint tokens.
-    function mint(address _to, uint256 _amount)
-        external
-        virtual
-        override(IOptimismMintableERC20, ILegacyMintableERC20)
-        onlyBridge
-    {
-        _mint(_to, _amount);
-        emit Mint(_to, _amount);
+    /* EXTERNAL */
+
+    /// @dev Allows the StandardBridge on this network to mint tokens.
+    function mint(address to, uint256 amount) external virtual override onlyBridge {
+        _mint(to, amount);
+        emit Mint(to, amount);
     }
 
-    ///@dev Allows the StandardBridge on this network to burn tokens.
-    function burn(address _from, uint256 _amount)
-        external
-        virtual
-        override(IOptimismMintableERC20, ILegacyMintableERC20)
-        onlyBridge
-    {
-        _burn(_from, _amount);
-        emit Burn(_from, _amount);
+    /// @dev Allows the StandardBridge on this network to burn tokens.
+    function burn(address from, uint256 amount) external virtual override onlyBridge {
+        _burn(from, amount);
+        emit Burn(from, amount);
     }
 
-    /**
-     * @notice ERC165 interface check function.
-     *
-     * @param _interfaceId Interface ID to check.
-     *
-     * @return Whether or not the interface is supported by this contract.
-     */
+    /// @notice ERC165 interface check function.
+    /// @param _interfaceId Interface ID to check.
+    /// @return Whether or not the interface is supported by this contract.
     function supportsInterface(bytes4 _interfaceId) external pure returns (bool) {
         bytes4 iface1 = type(IERC165).interfaceId;
-        // Interface corresponding to the legacy L2StandardERC20.
-        bytes4 iface2 = type(ILegacyMintableERC20).interfaceId;
         // Interface corresponding to the updated OptimismMintableERC20 (this contract).
         bytes4 iface3 = type(IOptimismMintableERC20).interfaceId;
-        return _interfaceId == iface1 || _interfaceId == iface2 || _interfaceId == iface3;
-    }
-
-    /// @dev Legacy getter for the remote token. Use REMOTE_TOKEN going forward.
-    function l1Token() public view returns (address) {
-        OptimismMintableERC20Storage storage $ = _getOptimismMintableERC20Storage();
-        return $._BRIDGE;
+        return _interfaceId == iface1 || _interfaceId == iface3;
     }
 
-    ///@dev Legacy getter for the bridge. Use BRIDGE going forward.
-    function l2Bridge() public view returns (address) {
-        OptimismMintableERC20Storage storage $ = _getOptimismMintableERC20Storage();
-        return $._BRIDGE;
-    }
+    /* PUBLIC */
 
-    ///@dev Legacy getter for REMOTE_TOKEN.
+    /// @custom:legacy
+    /// @dev Legacy getter for REMOTE_TOKEN.
     function remoteToken() public view returns (address) {
         OptimismMintableERC20Storage storage $ = _getOptimismMintableERC20Storage();
-        return $._REMOTE_TOKEN;
+        return $._remoteToken;
     }
 
-    ///@dev Legacy getter for BRIDGE.
+    /// @custom:legacy
+    /// @dev Legacy getter for BRIDGE.
     function bridge() public view returns (address) {
         OptimismMintableERC20Storage storage $ = _getOptimismMintableERC20Storage();
-        return $._BRIDGE;
+        return $._bridge;
     }
 
+    /* PRIVATE */
+
     /// @dev Returns the OptimismMintableERC20Storage struct.
     function _getOptimismMintableERC20Storage() private pure returns (OptimismMintableERC20Storage storage $) {
         assembly {

src/Wrapper.sol

@@ -4,7 +4,7 @@ pragma solidity 0.8.27;
 import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
 
 /// @title MorphoToken
-/// @author Morpho Labs
+/// @author Morpho Association
 /// @custom:contact security@morpho.org
 /// @notice The MORPHO Token contract.
 contract Wrapper {

src/interfaces/IDelegates.sol

@@ -2,7 +2,7 @@
 pragma solidity ^0.8.20;
 
 /// @title IDelegates
-/// @author Morpho Labs
+/// @author Morpho Association
 /// @custom:contact security@morpho.org
 /// @notice The Delegates interface.
 interface IDelegates {

src/interfaces/IOptimismMintableERC20.sol

@@ -13,20 +13,7 @@ interface IOptimismMintableERC20 is IERC165 {
 
     function bridge() external returns (address);
 
-    function mint(address _to, uint256 _amount) external;
+    function mint(address to, uint256 amount) external;
 
-    function burn(address _from, uint256 _amount) external;
-}
-
-/// @custom:legacy
-/// @title ILegacyMintableERC20
-/// @notice This interface was available on the legacy L2StandardERC20 contract.
-///         It remains available on the OptimismMintableERC20 contract for
-///         backwards compatibility.
-interface ILegacyMintableERC20 is IERC165 {
-    function l1Token() external view returns (address);
-
-    function mint(address _to, uint256 _amount) external;
-
-    function burn(address _from, uint256 _amount) external;
+    function burn(address from, uint256 amount) external;
 }

test/helpers/interfaces/IMulticall.sol

@@ -2,7 +2,7 @@
 pragma solidity >=0.5.0;
 
 /// @title IMulticall
-/// @author Morpho Labs
+/// @author Morpho Association
 /// @custom:contact security@morpho.org
 /// @notice Interface of Multicall.
 interface IMulticall {