feat(ctb): clean up initialization logic (#2942)

* feat(ctb): clean up initialization logic

Cleans and standardizes the initialization logic across all contracts.
Importantly, removes reinitialization.

* contracts-bedrock: clean up hh genesis task
Co-authored-by: Mark Tyneway <mark.tyneway@gmail.com>

.changeset/olive-tigers-build.md

+---
+'@eth-optimism/contracts-bedrock': patch
+---
+
+Cleans up initialization logic everywhere

packages/contracts-bedrock/.storage-layout

@@ -38,8 +38,6 @@
 | receivedMessages       | mapping(bytes32 => bool) | 205  | 0      | 32    | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
 |------------------------+--------------------------+------+--------+-------+----------------------------------------------------------------|
 | blockedSystemAddresses | mapping(address => bool) | 206  | 0      | 32    | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
-|------------------------+--------------------------+------+--------+-------+----------------------------------------------------------------|
-| portal                 | contract OptimismPortal  | 207  | 0      | 20    | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
 +------------------------+--------------------------+------+--------+-------+----------------------------------------------------------------+
 
 =======================
@@ -49,15 +47,15 @@
 +---------------+-------------------------------------------------+------+--------+-------+----------------------------------------------------+
 | Name          | Type                                            | Slot | Offset | Bytes | Contract                                           |
 +==============================================================================================================================================+
-| messenger     | contract CrossDomainMessenger                   | 0    | 0      | 20    | contracts/L1/L1StandardBridge.sol:L1StandardBridge |
+| _initialized  | uint8                                           | 0    | 0      | 1     | contracts/L1/L1StandardBridge.sol:L1StandardBridge |
 |---------------+-------------------------------------------------+------+--------+-------+----------------------------------------------------|
-| otherBridge   | contract StandardBridge                         | 1    | 0      | 20    | contracts/L1/L1StandardBridge.sol:L1StandardBridge |
+| _initializing | bool                                            | 0    | 1      | 1     | contracts/L1/L1StandardBridge.sol:L1StandardBridge |
 |---------------+-------------------------------------------------+------+--------+-------+----------------------------------------------------|
-| deposits      | mapping(address => mapping(address => uint256)) | 2    | 0      | 32    | contracts/L1/L1StandardBridge.sol:L1StandardBridge |
+| messenger     | contract CrossDomainMessenger                   | 0    | 2      | 20    | contracts/L1/L1StandardBridge.sol:L1StandardBridge |
 |---------------+-------------------------------------------------+------+--------+-------+----------------------------------------------------|
-| _initialized  | uint8                                           | 3    | 0      | 1     | contracts/L1/L1StandardBridge.sol:L1StandardBridge |
+| otherBridge   | contract StandardBridge                         | 1    | 0      | 20    | contracts/L1/L1StandardBridge.sol:L1StandardBridge |
 |---------------+-------------------------------------------------+------+--------+-------+----------------------------------------------------|
-| _initializing | bool                                            | 3    | 1      | 1     | contracts/L1/L1StandardBridge.sol:L1StandardBridge |
+| deposits      | mapping(address => mapping(address => uint256)) | 2    | 0      | 32    | contracts/L1/L1StandardBridge.sol:L1StandardBridge |
 +---------------+-------------------------------------------------+------+--------+-------+----------------------------------------------------+
 
 =======================
@@ -207,15 +205,19 @@
 ➡ L2StandardBridge
 =======================
 
-+-------------+-------------------------------------------------+------+--------+-------+----------------------------------------------------+
-| Name        | Type                                            | Slot | Offset | Bytes | Contract                                           |
-+============================================================================================================================================+
-| messenger   | contract CrossDomainMessenger                   | 0    | 0      | 20    | contracts/L2/L2StandardBridge.sol:L2StandardBridge |
-|-------------+-------------------------------------------------+------+--------+-------+----------------------------------------------------|
-| otherBridge | contract StandardBridge                         | 1    | 0      | 20    | contracts/L2/L2StandardBridge.sol:L2StandardBridge |
-|-------------+-------------------------------------------------+------+--------+-------+----------------------------------------------------|
-| deposits    | mapping(address => mapping(address => uint256)) | 2    | 0      | 32    | contracts/L2/L2StandardBridge.sol:L2StandardBridge |
-+-------------+-------------------------------------------------+------+--------+-------+----------------------------------------------------+
++---------------+-------------------------------------------------+------+--------+-------+----------------------------------------------------+
+| Name          | Type                                            | Slot | Offset | Bytes | Contract                                           |
++==============================================================================================================================================+
+| _initialized  | uint8                                           | 0    | 0      | 1     | contracts/L2/L2StandardBridge.sol:L2StandardBridge |
+|---------------+-------------------------------------------------+------+--------+-------+----------------------------------------------------|
+| _initializing | bool                                            | 0    | 1      | 1     | contracts/L2/L2StandardBridge.sol:L2StandardBridge |
+|---------------+-------------------------------------------------+------+--------+-------+----------------------------------------------------|
+| messenger     | contract CrossDomainMessenger                   | 0    | 2      | 20    | contracts/L2/L2StandardBridge.sol:L2StandardBridge |
+|---------------+-------------------------------------------------+------+--------+-------+----------------------------------------------------|
+| otherBridge   | contract StandardBridge                         | 1    | 0      | 20    | contracts/L2/L2StandardBridge.sol:L2StandardBridge |
+|---------------+-------------------------------------------------+------+--------+-------+----------------------------------------------------|
+| deposits      | mapping(address => mapping(address => uint256)) | 2    | 0      | 32    | contracts/L2/L2StandardBridge.sol:L2StandardBridge |
++---------------+-------------------------------------------------+------+--------+-------+----------------------------------------------------+
 
 =======================
 ➡ L2ToL1MessagePasser
@@ -341,8 +343,7 @@
 ➡ OptimismMintableERC20Factory
 =======================
 
-+--------+---------+------+--------+-------+-----------------------------------------------------------------------------------+
-| Name   | Type    | Slot | Offset | Bytes | Contract                                                                          |
-+==============================================================================================================================+
-| bridge | address | 0    | 0      | 20    | contracts/universal/OptimismMintableERC20Factory.sol:OptimismMintableERC20Factory |
-+--------+---------+------+--------+-------+-----------------------------------------------------------------------------------+
++------+------+------+--------+-------+----------+
+| Name | Type | Slot | Offset | Bytes | Contract |
++================================================+
++------+------+------+--------+-------+----------+

packages/contracts-bedrock/contracts/L1/L1CrossDomainMessenger.sol

@@ -13,34 +13,29 @@ import { CrossDomainMessenger } from "../universal/CrossDomainMessenger.sol";
  *         interface instead of interacting with lower-level contracts directly.
  */
 contract L1CrossDomainMessenger is CrossDomainMessenger {
-    /**
-     * @notice Contract version number.
-     */
-    uint8 public constant VERSION = 1;
-
     /**
      * @notice Address of the OptimismPortal.
      */
-    OptimismPortal public portal;
+    OptimismPortal public immutable portal;
 
     /**
-     * @param _portal Address of the OptimismPortal to send and receive messages through.
+     * @param _portal Address of the OptimismPortal contract on this network.
      */
     constructor(OptimismPortal _portal) public {
-        // Mutables
-        initialize(_portal);
+        portal = _portal;
+        initialize();
     }
 
     /**
-     * @notice Intializes mutable variables.
-     *
-     * @param _portal Address of the OptimismPortal to send and receive messages through.
+     * @notice Initializer.
      */
-    function initialize(OptimismPortal _portal) public reinitializer(VERSION) {
-        portal = _portal;
+    function initialize() public initializer {
         address[] memory blockedSystemAddresses = new address[](1);
         blockedSystemAddresses[0] = address(this);
-        _initialize(PredeployAddresses.L2_CROSS_DOMAIN_MESSENGER, blockedSystemAddresses);
+        __CrossDomainMessenger_init(
+            PredeployAddresses.L2_CROSS_DOMAIN_MESSENGER,
+            blockedSystemAddresses
+        );
     }
 
     /**

packages/contracts-bedrock/contracts/L1/L1StandardBridge.sol

 // SPDX-License-Identifier: MIT
 pragma solidity ^0.8.9;
 
-import { Initializable } from "@openzeppelin/contracts/proxy/utils/Initializable.sol";
 import { PredeployAddresses } from "../libraries/PredeployAddresses.sol";
 import { StandardBridge } from "../universal/StandardBridge.sol";
 
@@ -12,12 +11,7 @@ import { StandardBridge } from "../universal/StandardBridge.sol";
  *         L2. ERC20 tokens deposited into L2 are escrowed within this contract until withdrawal.
  *         ETH is transferred to and escrowed within the OptimismPortal contract.
  */
-contract L1StandardBridge is StandardBridge, Initializable {
-    /**
-     * @notice Contract version number.
-     */
-    uint8 public constant VERSION = 1;
-
+contract L1StandardBridge is StandardBridge {
     /**
      * @custom:legacy
      * @notice Emitted whenever a deposit of ETH from L1 into L2 is initiated.
@@ -94,17 +88,16 @@ contract L1StandardBridge is StandardBridge, Initializable {
      * @param _messenger Address of the L1CrossDomainMessenger.
      */
     constructor(address payable _messenger) public {
-        // Mutables
         initialize(_messenger);
     }
 
     /**
-     * @notice Intializes mutable variables.
+     * @notice Initializer.
      *
      * @param _messenger Address of the L1CrossDomainMessenger.
      */
-    function initialize(address payable _messenger) public reinitializer(VERSION) {
-        _initialize(_messenger, payable(PredeployAddresses.L2_STANDARD_BRIDGE));
+    function initialize(address payable _messenger) public initializer {
+        __StandardBridge_init(_messenger, payable(PredeployAddresses.L2_STANDARD_BRIDGE));
     }
 
     /**

packages/contracts-bedrock/contracts/L1/L2OutputOracle.sol

@@ -14,11 +14,6 @@ import {
  */
 // slither-disable-next-line locked-ether
 contract L2OutputOracle is OwnableUpgradeable {
-    /**
-     * @notice Contract version number.
-     */
-    uint8 public constant VERSION = 1;
-
     /**
      * @notice OutputProposal represents a commitment to the L2 state.
      *         The timestamp is the L1 timestamp that the output root is posted.
@@ -139,19 +134,17 @@ contract L2OutputOracle is OwnableUpgradeable {
             "Output Oracle: Initial L2 block time must be less than current time"
         );
 
-        // Immutables
         SUBMISSION_INTERVAL = _submissionInterval;
         HISTORICAL_TOTAL_BLOCKS = _historicalTotalBlocks;
         STARTING_BLOCK_NUMBER = _startingBlockNumber;
         STARTING_TIMESTAMP = _startingTimestamp;
         L2_BLOCK_TIME = _l2BlockTime;
 
-        // Mutables
         initialize(_genesisL2Output, _startingBlockNumber, _sequencer, _owner);
     }
 
     /**
-     * @notice Intializes mutable variables.
+     * @notice Initializer.
      *
      * @param _genesisL2Output     The initial L2 output of the L2 chain.
      * @param _startingBlockNumber The timestamp to start L2 block at.
@@ -163,7 +156,7 @@ contract L2OutputOracle is OwnableUpgradeable {
         uint256 _startingBlockNumber,
         address _sequencer,
         address _owner
-    ) public reinitializer(VERSION) {
+    ) public initializer {
         l2Outputs[_startingBlockNumber] = OutputProposal(_genesisL2Output, block.timestamp);
         latestBlockNumber = _startingBlockNumber;
         __Ownable_init();

packages/contracts-bedrock/contracts/L1/OptimismPortal.sol

@@ -16,11 +16,6 @@ import { ResourceMetering } from "./ResourceMetering.sol";
  *         Users are encouraged to use the L1CrossDomainMessenger for a higher-level interface.
  */
 contract OptimismPortal is Initializable, ResourceMetering {
-    /**
-     * @notice Contract version number.
-     */
-    uint8 public constant VERSION = 1;
-
     /**
      * @notice Emitted when a transaction is deposited from L1 to L2. The parameters of this event
      *         are read by the rollup node and used to derive deposit transactions on L2.
@@ -98,18 +93,16 @@ contract OptimismPortal is Initializable, ResourceMetering {
      * @param _finalizationPeriodSeconds Output finalization time in seconds.
      */
     constructor(L2OutputOracle _l2Oracle, uint256 _finalizationPeriodSeconds) {
-        // Immutables
         L2_ORACLE = _l2Oracle;
         FINALIZATION_PERIOD_SECONDS = _finalizationPeriodSeconds;
 
-        // Mutables
         initialize();
     }
 
     /**
      * @notice Intializes mutable variables.
      */
-    function initialize() public reinitializer(VERSION) {
+    function initialize() public initializer {
         l2Sender = DEFAULT_L2_SENDER;
         __ResourceMetering_init();
     }

packages/contracts-bedrock/contracts/L2/L2CrossDomainMessenger.sol

@@ -16,16 +16,22 @@ import { L2ToL1MessagePasser } from "./L2ToL1MessagePasser.sol";
  */
 contract L2CrossDomainMessenger is CrossDomainMessenger {
     /**
-     * @notice Initializes the L2CrossDomainMessenger.
+     * @param _l1CrossDomainMessenger Address of the L1CrossDomainMessenger contract.
+     */
+    constructor(address _l1CrossDomainMessenger) {
+        initialize(_l1CrossDomainMessenger);
+    }
+
+    /**
+     * @notice Initializer.
      *
      * @param _l1CrossDomainMessenger Address of the L1CrossDomainMessenger contract.
      */
-    function initialize(address _l1CrossDomainMessenger) external initializer {
+    function initialize(address _l1CrossDomainMessenger) public initializer {
         address[] memory blockedSystemAddresses = new address[](2);
         blockedSystemAddresses[0] = address(this);
         blockedSystemAddresses[1] = PredeployAddresses.L2_TO_L1_MESSAGE_PASSER;
-
-        _initialize(_l1CrossDomainMessenger, blockedSystemAddresses);
+        __CrossDomainMessenger_init(_l1CrossDomainMessenger, blockedSystemAddresses);
     }
 
     /**

packages/contracts-bedrock/contracts/L2/L2StandardBridge.sol

@@ -79,12 +79,19 @@ contract L2StandardBridge is StandardBridge {
     );
 
     /**
-     * @notice Initializes the L2StandardBridge.
+     * @param _otherBridge Address of the L1StandardBridge.
+     */
+    constructor(address payable _otherBridge) {
+        initialize(_otherBridge);
+    }
+
+    /**
+     * @notice Initializer.
      *
      * @param _otherBridge Address of the L1StandardBridge.
      */
-    function initialize(address payable _otherBridge) public {
-        _initialize(payable(PredeployAddresses.L2_CROSS_DOMAIN_MESSENGER), _otherBridge);
+    function initialize(address payable _otherBridge) public initializer {
+        __StandardBridge_init(payable(PredeployAddresses.L2_CROSS_DOMAIN_MESSENGER), _otherBridge);
     }
 
     /**

packages/contracts-bedrock/contracts/test/CommonTest.t.sol

@@ -190,11 +190,11 @@ contract Messenger_Initializer is L2OutputOracle_Initializer {
             "OVM_L1CrossDomainMessenger"
         );
         L1Messenger = L1CrossDomainMessenger(address(proxy));
-        L1Messenger.initialize(op);
+        L1Messenger.initialize();
 
         vm.etch(
             PredeployAddresses.L2_CROSS_DOMAIN_MESSENGER,
-            address(new L2CrossDomainMessenger()).code
+            address(new L2CrossDomainMessenger(address(L1Messenger))).code
         );
 
         L2Messenger.initialize(address(L1Messenger));
@@ -358,18 +358,19 @@ contract Bridge_Initializer is Messenger_Initializer {
 
         // Deploy the L2StandardBridge, move it to the correct predeploy
         // address and then initialize it
-        L2StandardBridge l2B = new L2StandardBridge();
+        L2StandardBridge l2B = new L2StandardBridge(payable(PredeployAddresses.L2_STANDARD_BRIDGE));
         vm.etch(PredeployAddresses.L2_STANDARD_BRIDGE, address(l2B).code);
         L2Bridge = L2StandardBridge(payable(PredeployAddresses.L2_STANDARD_BRIDGE));
         L2Bridge.initialize(payable(address(L1Bridge)));
 
         // Set up the L2 mintable token factory
-        OptimismMintableERC20Factory factory = new OptimismMintableERC20Factory();
+        OptimismMintableERC20Factory factory = new OptimismMintableERC20Factory(
+            PredeployAddresses.L2_STANDARD_BRIDGE
+        );
         vm.etch(PredeployAddresses.L2_STANDARD_TOKEN_FACTORY, address(factory).code);
         L2TokenFactory = OptimismMintableERC20Factory(
             PredeployAddresses.L2_STANDARD_TOKEN_FACTORY
         );
-        L2TokenFactory.initialize(PredeployAddresses.L2_STANDARD_BRIDGE);
 
         vm.etch(PredeployAddresses.LEGACY_ERC20_ETH, address(new LegacyERC20ETH()).code);
 
@@ -385,8 +386,7 @@ contract Bridge_Initializer is Messenger_Initializer {
         );
 
         NativeL2Token = new ERC20("Native L2 Token", "L2T");
-        L1TokenFactory = new OptimismMintableERC20Factory();
-        L1TokenFactory.initialize(address(L1Bridge));
+        L1TokenFactory = new OptimismMintableERC20Factory(address(L1Bridge));
 
         RemoteL1Token = OptimismMintableERC20(
             L1TokenFactory.createStandardL2Token(

packages/contracts-bedrock/contracts/test/OptimismMintableERC20Factory.t.sol

@@ -16,11 +16,6 @@ contract OptimismMintableTokenFactory_Test is Bridge_Initializer {
         super.setUp();
     }
 
-    function test_initializeShouldRevert() external {
-        vm.expectRevert("OptimismMintableERC20Factory: already initialized");
-        L2TokenFactory.initialize(address(L1Bridge));
-    }
-
     function test_bridge() external {
         assertEq(address(L2TokenFactory.bridge()), address(L2Bridge));
     }

packages/contracts-bedrock/contracts/universal/CrossDomainMessenger.sol

@@ -312,18 +312,16 @@ abstract contract CrossDomainMessenger is
      *                                detailed information about what this block list can and
      *                                cannot be used for.
      */
-    function _initialize(address _otherMessenger, address[] memory _blockedSystemAddresses)
-        internal
-    {
+    function __CrossDomainMessenger_init(
+        address _otherMessenger,
+        address[] memory _blockedSystemAddresses
+    ) internal onlyInitializing {
         xDomainMsgSender = DEFAULT_XDOMAIN_SENDER;
         otherMessenger = _otherMessenger;
-
         for (uint256 i = 0; i < _blockedSystemAddresses.length; i++) {
             blockedSystemAddresses[_blockedSystemAddresses[i]] = true;
         }
 
-        // TODO: ensure we know what these are doing and why they are here
-        // Initialize upgradable OZ contracts
         __Context_init_unchained();
         __Ownable_init_unchained();
         __Pausable_init_unchained();

packages/contracts-bedrock/contracts/universal/OptimismMintableERC20Factory.sol

@@ -41,15 +41,12 @@ contract OptimismMintableERC20Factory {
     /**
      * @notice Address of the StandardBridge on this chain.
      */
-    address public bridge;
+    address public immutable bridge;
 
     /**
-     * @notice Initializer.
-     *
      * @param _bridge Address of the StandardBridge on this chain.
      */
-    function initialize(address _bridge) public {
-        require(bridge == address(0), "OptimismMintableERC20Factory: already initialized");
+    constructor(address _bridge) {
         bridge = _bridge;
     }
 

packages/contracts-bedrock/contracts/universal/StandardBridge.sol

@@ -5,6 +5,7 @@ import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
 import { ERC165Checker } from "@openzeppelin/contracts/utils/introspection/ERC165Checker.sol";
 import { Address } from "@openzeppelin/contracts/utils/Address.sol";
 import { SafeERC20 } from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
+import { Initializable } from "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol";
 import { IRemoteToken, IL1Token } from "./SupportedInterfaces.sol";
 import { CrossDomainMessenger } from "./CrossDomainMessenger.sol";
 import { OptimismMintableERC20 } from "./OptimismMintableERC20.sol";
@@ -13,7 +14,7 @@ import { OptimismMintableERC20 } from "./OptimismMintableERC20.sol";
  * @title StandardBridge
  * @notice StandardBridge is a base contract for the L1 and L2 standard ERC20 bridges.
  */
-abstract contract StandardBridge {
+abstract contract StandardBridge is Initializable {
     using SafeERC20 for IERC20;
 
     /**
@@ -367,9 +368,10 @@ abstract contract StandardBridge {
      * @param _messenger   Address of CrossDomainMessenger on this network.
      * @param _otherBridge Address of the other StandardBridge contract.
      */
-    function _initialize(address payable _messenger, address payable _otherBridge) internal {
-        require(address(messenger) == address(0), "Contract has already been initialized.");
-
+    function __StandardBridge_init(address payable _messenger, address payable _otherBridge)
+        internal
+        onlyInitializing
+    {
         messenger = CrossDomainMessenger(_messenger);
         otherBridge = StandardBridge(_otherBridge);
     }

packages/contracts-bedrock/deploy/002-L1CrossDomainMessenger.ts

@@ -37,9 +37,7 @@ const deployFn: DeployFunction = async (hre) => {
 
   const upgradeTx = await Proxy.upgradeToAndCall(
     messenger.address,
-    L1CrossDomainMessenger.interface.encodeFunctionData('initialize(address)', [
-      portal.address,
-    ])
+    L1CrossDomainMessenger.interface.encodeFunctionData('initialize')
   )
   await upgradeTx.wait()
 

packages/contracts-bedrock/deploy/004-OptimismMintableTokenFactory.ts

@@ -17,15 +17,16 @@ const deployFn: DeployFunction = async (hre) => {
     waitConfirmations: deployConfig.deploymentWaitConfirmations,
   })
 
+  const bridge = await hre.deployments.get('L1StandardBridgeProxy')
+
   await deploy('OptimismMintableERC20Factory', {
     from: deployer,
-    args: [],
+    args: [bridge.address],
     log: true,
     waitConfirmations: deployConfig.deploymentWaitConfirmations,
   })
 
   const factory = await hre.deployments.get('OptimismMintableERC20Factory')
-  const bridge = await hre.deployments.get('L1StandardBridgeProxy')
   const proxy = await hre.deployments.get('OptimismMintableERC20FactoryProxy')
   const Proxy = await hre.ethers.getContractAt('Proxy', proxy.address)
 
@@ -34,13 +35,7 @@ const deployFn: DeployFunction = async (hre) => {
     proxy.address
   )
 
-  const upgradeTx = await Proxy.upgradeToAndCall(
-    factory.address,
-    OptimismMintableERC20Factory.interface.encodeFunctionData(
-      'initialize(address)',
-      [bridge.address]
-    )
-  )
+  const upgradeTx = await Proxy.upgradeTo(factory.address)
   await upgradeTx.wait()
 
   if (bridge.address !== (await OptimismMintableERC20Factory.bridge())) {

packages/contracts-bedrock/tasks/genesis-l2.ts

@@ -3,6 +3,7 @@ import path from 'path'
 import assert from 'assert'
 
 import { OptimismGenesis, State } from '@eth-optimism/core-utils'
+import 'hardhat-deploy'
 import '@eth-optimism/hardhat-deploy-config'
 import { ethers } from 'ethers'
 import { task } from 'hardhat/config'
@@ -38,7 +39,8 @@ const getStorageLayout = async (
   for (const key of keys) {
     if (name === path.basename(key, '.sol')) {
       const contract = buildInfo.output.contracts[key]
-      return (contract[name] as any).storageLayout
+      const storageLayout = (contract[name] as any).storageLayout
+      return storageLayout || { storage: [], types: {} }
     }
   }
   throw new Error(`Cannot locate storageLayout for ${name}`)
@@ -102,9 +104,6 @@ task('genesis-l2', 'create a genesis config')
       SequencerFeeVault: {
         l1FeeWallet: ethers.constants.AddressZero,
       },
-      OptimismMintableERC20Factory: {
-        bridge: ethers.constants.AddressZero,
-      },
       L1Block: {
         number: deployConfig.l1BlockInitialNumber,
         timestamp: deployConfig.l1BlockInitialTimestamp,
@@ -247,6 +246,9 @@ task('genesis-l2', 'create a genesis config')
       }
 
       const storageLayout = await getStorageLayout(hre, name)
+      if (storageLayout === undefined) {
+        throw new Error(`cannot find storage layout for ${name}`)
+      }
       const slots = computeStorageSlots(storageLayout, variables[name])
 
       for (const slot of slots) {