style(ctb): tweaks to L2 contracts (#2886)

Minor style tweaks to a few L2 contracts.

packages/contracts-bedrock/contracts/L2/DeployerWhitelist.sol

@@ -2,47 +2,65 @@
 pragma solidity ^0.8.9;
 
 /**
- * @title OVM_DeployerWhitelist
- * @dev The Deployer Whitelist is a temporary predeploy used to provide additional safety during the
- * initial phases of our mainnet roll out. It is owned by the Optimism team, and defines accounts
- * which are allowed to deploy contracts on Layer2. The Execution Manager will only allow an
- * ovmCREATE or ovmCREATE2 operation to proceed if the deployer's address whitelisted.
+ * @custom:legacy
+ * @custom:proxied
+ * @custom:predeployed 0x4200000000000000000000000000000000000002
+ * @title DeployerWhitelist
+ * @notice DeployerWhitelist is a legacy contract that was originally used to act as a whitelist of
+ *         addresses allowed to the Optimism network. The DeployerWhitelist has since been
+ *         disabled, but the code is kept in state for the sake of full backwards compatibility.
+ *         As of the Bedrock upgrade, the DeployerWhitelist is completely unused by the Optimism
+ *         system and could, in theory, be removed entirely.
  */
 contract DeployerWhitelist {
-    /**********
-     * Events *
-     **********/
-
+    /**
+     * @notice Emitted when the owner of this contract changes.
+     *
+     * @param oldOwner Address of the previous owner.
+     * @param newOwner Address of the new owner.
+     */
     event OwnerChanged(address oldOwner, address newOwner);
+
+    /**
+     * @notice Emitted when the whitelist status of a deployer changes.
+     *
+     * @param deployer    Address of the deployer.
+     * @param whitelisted Boolean indicating whether the deployer is whitelisted.
+     */
     event WhitelistStatusChanged(address deployer, bool whitelisted);
-    event WhitelistDisabled(address oldOwner);
 
-    /**********************
-     * Contract Constants *
-     **********************/
+    /**
+     * @notice Emitted when the whitelist is disabled.
+     *
+     * @param oldOwner Address of the final owner of the whitelist.
+     */
+    event WhitelistDisabled(address oldOwner);
 
-    // WARNING: When owner is set to address(0), the whitelist is disabled.
+    /**
+     * @notice Address of the owner of this contract. Note that when this address is set to
+     *         address(0), the whitelist is disabled.
+     */
     address public owner;
-    mapping(address => bool) public whitelist;
 
-    /**********************
-     * Function Modifiers *
-     **********************/
+    /**
+     * @notice Mapping of deployer addresses to boolean whitelist status.
+     */
+    mapping(address => bool) public whitelist;
 
     /**
-     * Blocks functions to anyone except the contract owner.
+     * @notice Blocks functions to anyone except the contract owner.
      */
     modifier onlyOwner() {
-        require(msg.sender == owner, "Function can only be called by the owner of this contract.");
+        require(
+            msg.sender == owner,
+            "DeployerWhitelist: function can only be called by the owner of this contract"
+        );
         _;
     }
 
-    /********************
-     * Public Functions *
-     ********************/
-
     /**
-     * Adds or removes an address from the deployment whitelist.
+     * @notice Adds or removes an address from the deployment whitelist.
+     *
      * @param _deployer      Address to update permissions for.
      * @param _isWhitelisted Whether or not the address is whitelisted.
      */
@@ -52,17 +70,17 @@ contract DeployerWhitelist {
     }
 
     /**
-     * Updates the owner of this contract.
+     * @notice Updates the owner of this contract.
+     *
      * @param _owner Address of the new owner.
      */
-    // slither-disable-next-line external-function
-    function setOwner(address _owner) public onlyOwner {
+    function setOwner(address _owner) external onlyOwner {
         // Prevent users from setting the whitelist owner to address(0) except via
         // enableArbitraryContractDeployment. If you want to burn the whitelist owner, send it to
         // any other address that doesn't have a corresponding knowable private key.
         require(
             _owner != address(0),
-            "OVM_DeployerWhitelist: can only be disabled via enableArbitraryContractDeployment"
+            "DeployerWhitelist: can only be disabled via enableArbitraryContractDeployment"
         );
 
         emit OwnerChanged(owner, _owner);
@@ -70,7 +88,7 @@ contract DeployerWhitelist {
     }
 
     /**
-     * Permanently enables arbitrary contract deployment and deletes the owner.
+     * @notice Permanently enables arbitrary contract deployment and deletes the owner.
      */
     function enableArbitraryContractDeployment() external onlyOwner {
         emit WhitelistDisabled(owner);
@@ -78,9 +96,11 @@ contract DeployerWhitelist {
     }
 
     /**
-     * Checks whether an address is allowed to deploy contracts.
+     * @notice Checks whether an address is allowed to deploy contracts.
+     *
      * @param _deployer Address to check.
-     * @return _allowed Whether or not the address can deploy contracts.
+     *
+     * @return Whether or not the address can deploy contracts.
      */
     function isDeployerAllowed(address _deployer) external view returns (bool) {
         return (owner == address(0) || whitelist[_deployer]);

packages/contracts-bedrock/contracts/L2/L2ToL1MessagePasser.sol

@@ -39,19 +39,11 @@ contract L2ToL1MessagePasser {
      */
     event WithdrawerBalanceBurnt(uint256 indexed amount);
 
-    /*************
-     * Constants *
-     *************/
-
     /**
      * @notice The L1 gas limit set when eth is withdrawn using the receive() function.
      */
     uint256 internal constant RECEIVE_DEFAULT_GAS_LIMIT = 100_000;
 
-    /*************
-     * Variables *
-     *************/
-
     /**
      * @notice Includes the message hashes for all withdrawals
      */

packages/contracts-bedrock/contracts/L2/OVM_ETH.sol

@@ -8,10 +8,14 @@ import { Lib_PredeployAddresses } from "../libraries/Lib_PredeployAddresses.sol"
 import { OptimismMintableERC20 } from "../universal/OptimismMintableERC20.sol";
 
 /**
+ * @custom:legacy
  * @custom:proxied
  * @custom:predeploy 0xDeadDeAddeAddEAddeadDEaDDEAdDeaDDeAD0000
  * @title OVM_ETH
- * @notice Legacy contract which used to hold ETH balances on L2.
+ * @notice OVM_ETH is a legacy contract that held ETH balances before the Bedrock upgrade. All
+ *         ETH balances held within this contract were migrated to the state trie as part of the
+ *         Bedrock upgrade. Functions within this contract that mutate state were already disabled
+ *         as part of the EVM equivalence upgrade.
  */
 contract OVM_ETH is OptimismMintableERC20 {
     /**