feat: introduce OptimismSuperchainERC20

.gitmodules

@@ -26,3 +26,6 @@
 [submodule "packages/contracts-bedrock/lib/automate"]
 	path = packages/contracts-bedrock/lib/automate
 	url = https://github.com/gelatodigital/automate
+[submodule "packages/contracts-bedrock/lib/openzeppelin-contracts-v5"]
+	path = packages/contracts-bedrock/lib/openzeppelin-contracts-v5
+	url = https://github.com/OpenZeppelin/openzeppelin-contracts

packages/contracts-bedrock/foundry.toml

@@ -13,6 +13,7 @@ optimizer_runs = 999999
 remappings = [
   '@openzeppelin/contracts-upgradeable/=lib/openzeppelin-contracts-upgradeable/contracts',
   '@openzeppelin/contracts/=lib/openzeppelin-contracts/contracts',
+  '@openzeppelin/contracts-v5/=lib/openzeppelin-contracts-v5/contracts',
   '@rari-capital/solmate/=lib/solmate',
   '@lib-keccak/=lib/lib-keccak/contracts/lib',
   '@solady/=lib/solady/src',

packages/contracts-bedrock/invariant-docs/OptimismSuperchainERC20.md

@@ -1,5 +1,5 @@
 # `OptimismSuperchainERC20` Invariants
 
 ## Calls to sendERC20 should always succeed as long as the actor has enough balance. Actor's balance should also not increase out of nowhere.
-**Test:** [`OptimismSuperchainERC20.t.sol#L150`](../test/invariants/OptimismSuperchainERC20.t.sol#L150)
+**Test:** [`OptimismSuperchainERC20.t.sol#L177`](../test/invariants/OptimismSuperchainERC20.t.sol#L177)
 

packages/contracts-bedrock/semver-lock.json

@@ -104,8 +104,8 @@
     "sourceCodeHash": "0x1f14aafab2cb15970cccedb461b72218fca8afa6ffd0ac696a9e28ff1415a068"
   },
   "src/L2/OptimismSuperchainERC20.sol": {
-    "initCodeHash": "0x3ca4452dc167b6705a017016c9f1bf7f765cf871efdac56707735d6b9354d5e8",
-    "sourceCodeHash": "0x99861db89dde9af91df484816d35b4fd29b612d08cb6ef242699f627756602c4"
+    "initCodeHash": "0xbfa1d35644a8b97c657101289e64b92b8faeed0b0090195eb871da2de4583bb3",
+    "sourceCodeHash": "0x56bed1f02792ef9513fe209552e964c983a8f29dbcb2b8a76910fdae929f30ff"
   },
   "src/L2/SequencerFeeVault.sol": {
     "initCodeHash": "0xb94145f571e92ee615c6fe903b6568e8aac5fe760b6b65148ffc45d2fb0f5433",

packages/contracts-bedrock/snapshots/abi/OptimismSuperchainERC20.json

@@ -119,22 +119,22 @@
     "inputs": [
       {
         "internalType": "address",
-        "name": "__remoteToken",
+        "name": "_remoteToken",
         "type": "address"
       },
       {
         "internalType": "string",
-        "name": "__name",
+        "name": "_name",
         "type": "string"
       },
       {
         "internalType": "string",
-        "name": "__symbol",
+        "name": "_symbol",
         "type": "string"
       },
       {
         "internalType": "uint8",
-        "name": "__decimals",
+        "name": "_decimals",
         "type": "uint8"
       }
     ],

packages/contracts-bedrock/snapshots/storageLayout/OptimismSuperchainERC20.json

@@ -1,30 +1 @@
-[
-  {
-    "bytes": "20",
-    "label": "_remoteToken",
-    "offset": 0,
-    "slot": "0",
-    "type": "address"
-  },
-  {
-    "bytes": "32",
-    "label": "_name",
-    "offset": 0,
-    "slot": "1",
-    "type": "string"
-  },
-  {
-    "bytes": "32",
-    "label": "_symbol",
-    "offset": 0,
-    "slot": "2",
-    "type": "string"
-  },
-  {
-    "bytes": "1",
-    "label": "_decimals",
-    "offset": 0,
-    "slot": "3",
-    "type": "uint8"
-  }
-]
+[]

packages/contracts-bedrock/src/L2/IOptimismSuperchainERC20.sol

@@ -52,6 +52,6 @@ interface IOptimismSuperchainERC20 {
     /// @param _amount  Amount of tokens to relay.
     function relayERC20(address _from, address _to, uint256 _amount) external;
 
-    /// @notice Returns the address of the corresponding remote token.
+    /// @notice Returns the address of the corresponding version of this token on the remote chain.
     function remoteToken() external view returns (address);
 }

packages/contracts-bedrock/src/L2/OptimismSuperchainERC20.sol

@@ -6,7 +6,7 @@ import { ERC20 } from "@solady/tokens/ERC20.sol";
 import { IL2ToL2CrossDomainMessenger } from "src/L2/IL2ToL2CrossDomainMessenger.sol";
 import { ISemver } from "src/universal/ISemver.sol";
 import { Predeploys } from "src/libraries/Predeploys.sol";
-import { Initializable } from "@solady/utils/Initializable.sol";
+import { Initializable } from "@openzeppelin/contracts-v5/proxy/utils/Initializable.sol";
 
 /// @notice Thrown when attempting to relay a message and the function caller (msg.sender) is not
 /// L2ToL2CrossDomainMessenger.
@@ -37,17 +37,29 @@ contract OptimismSuperchainERC20 is IOptimismSuperchainERC20, ERC20, ISemver, In
     /// @notice Address of the StandardBridge Predeploy.
     address internal constant BRIDGE = Predeploys.L2_STANDARD_BRIDGE;
 
-    /// @notice Address of the corresponding version of this token on the remote chain.
-    address private _remoteToken;
-
-    /// @notice Name of the token
-    string private _name;
-
-    /// @notice Symbol of the token
-    string private _symbol;
+    /// @notice Storage slot that the OptimismSuperchainERC20Metadata struct is stored at.
+    bytes32 internal constant OPTIMISM_SUPERCHAIN_ERC20_METADATA_SLOT =
+        bytes32(uint256(keccak256("optimismSuperchainERC20Metadata")) - 1);
+
+    /// @notice Storage struct for the OptimismSuperchainERC20 metadata.
+    struct OptimismSuperchainERC20Metadata {
+        /// @notice Address of the corresponding version of this token on the remote chain.
+        address remoteToken;
+        /// @notice Name of the token
+        string name;
+        /// @notice Symbol of the token
+        string symbol;
+        /// @notice Decimals of the token
+        uint8 decimals;
+    }
 
-    /// @notice Decimals of the token
-    uint8 private _decimals;
+    /// @notice Returns the storage for the OptimismSuperchainERC20Metadata.
+    function _getMetadataStorage() private pure returns (OptimismSuperchainERC20Metadata storage _storage) {
+        bytes32 _slot = OPTIMISM_SUPERCHAIN_ERC20_METADATA_SLOT;
+        assembly {
+            _storage.slot := _slot
+        }
+    }
 
     /// @notice A modifier that only allows the bridge to call
     modifier onlyBridge() {
@@ -65,23 +77,24 @@ contract OptimismSuperchainERC20 is IOptimismSuperchainERC20, ERC20, ISemver, In
     }
 
     /// @notice Initializes the contract.
-    /// @param __remoteToken    Address of the corresponding remote token.
-    /// @param __name           ERC20 name.
-    /// @param __symbol         ERC20 symbol.
-    /// @param __decimals       ERC20 decimals.
+    /// @param _remoteToken    Address of the corresponding remote token.
+    /// @param _name           ERC20 name.
+    /// @param _symbol         ERC20 symbol.
+    /// @param _decimals       ERC20 decimals.
     function initialize(
-        address __remoteToken,
-        string memory __name,
-        string memory __symbol,
-        uint8 __decimals
+        address _remoteToken,
+        string memory _name,
+        string memory _symbol,
+        uint8 _decimals
     )
         external
         initializer
     {
-        _remoteToken = __remoteToken;
-        _name = __name;
-        _symbol = __symbol;
-        _decimals = __decimals;
+        OptimismSuperchainERC20Metadata storage _storage = _getMetadataStorage();
+        _storage.remoteToken = _remoteToken;
+        _storage.name = _name;
+        _storage.symbol = _symbol;
+        _storage.decimals = _decimals;
     }
 
     /// @notice Allows the L2StandardBridge to mint tokens.
@@ -140,19 +153,19 @@ contract OptimismSuperchainERC20 is IOptimismSuperchainERC20, ERC20, ISemver, In
         emit RelayedERC20(_from, _to, _amount, _source);
     }
 
-    /// @notice Returns the address of the corresponding remote token.
+    /// @notice Returns the address of the corresponding version of this token on the remote chain.
     function remoteToken() public view override returns (address) {
-        return _remoteToken;
+        return _getMetadataStorage().remoteToken;
     }
 
     /// @notice Returns the name of the token.
     function name() public view virtual override returns (string memory) {
-        return _name;
+        return _getMetadataStorage().name;
     }
 
     /// @notice Returns the symbol of the token.
     function symbol() public view virtual override returns (string memory) {
-        return _symbol;
+        return _getMetadataStorage().symbol;
     }
 
     /// @notice Returns the number of decimals used to get its user representation.
@@ -162,7 +175,7 @@ contract OptimismSuperchainERC20 is IOptimismSuperchainERC20, ERC20, ISemver, In
     /// no way affects any of the arithmetic of the contract, including
     /// {IERC20-balanceOf} and {IERC20-transfer}.
     function decimals() public view override returns (uint8) {
-        return _decimals;
+        return _getMetadataStorage().decimals;
     }
 
     /// @notice ERC165 interface check function.

packages/contracts-bedrock/test/L2/OptimismSuperchainERC20.t.sol

@@ -11,7 +11,7 @@ import { stdStorage, StdStorage } from "forge-std/Test.sol";
 import { ERC20 } from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
 import { IL2ToL2CrossDomainMessenger } from "src/L2/IL2ToL2CrossDomainMessenger.sol";
 import { ERC1967Proxy } from "@openzeppelin/contracts/proxy/ERC1967/ERC1967Proxy.sol";
-import { Initializable } from "@solady/utils/Initializable.sol";
+import { Initializable } from "@openzeppelin/contracts-v5/proxy/utils/Initializable.sol";
 
 // Target contract
 import {

packages/contracts-bedrock/test/vendor/Initializable.t.sol

@@ -352,7 +352,8 @@ contract Initializer_Test is Bridge_Initializer {
         // Ensure that all L1, L2 `Initializable` contracts are accounted for, in addition to
         // OptimismMintableERC20FactoryImpl, OptimismMintableERC20FactoryProxy, OptimismPortal2,
         // DisputeGameFactoryImpl, DisputeGameFactoryProxy, DelayedWETHImpl, DelayedWETHProxy.
-        assertEq(_getNumInitializable() + 1, contracts.length);
+        // Omitting OptimismSuperchainERC20 due to using OZ v5 Initializable.
+        assertEq(_getNumInitializable(), contracts.length);
 
         // Attempt to re-initialize all contracts within the `contracts` array.
         for (uint256 i; i < contracts.length; i++) {