feat: add crosschain erc20 interface

packages/contracts-bedrock/semver-lock.json

@@ -116,7 +116,7 @@
     "sourceCodeHash": "0xfea53344596d735eff3be945ed1300dc75a6f8b7b2c02c0043af5b0036f5f239"
   },
   "src/L2/OptimismSuperchainERC20.sol": {
-    "initCodeHash": "0xc6452d9aef6d76bdc789f3cddac6862658a481c619e6a2e7a74f6d61147f927b",
+    "initCodeHash": "0x964c826693c6633dc5eff6d4b059a30043775af46b06e42367aff91b904498da",
     "sourceCodeHash": "0x4463e49c98ceb3327bd768579341d1e0863c8c3925d4b533fbc0f7951306261f"
   },
   "src/L2/OptimismSuperchainERC20Beacon.sol": {
@@ -133,11 +133,11 @@
   },
   "src/L2/SuperchainERC20.sol": {
     "initCodeHash": "0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470",
-    "sourceCodeHash": "0x9bc2e208774eb923894dbe391a5038a6189d7d36c202f4bf3e2c4dd332b0adf0"
+    "sourceCodeHash": "0x770764a897f76912ff5ad315ab7101f7777b8be47f21021d56cb9572b9efa458"
   },
   "src/L2/SuperchainERC20Bridge.sol": {
-    "initCodeHash": "0xea7eb314f96cd2520a58012ff7cc376c82c5a95612187ff6bb96ace4f095ebc4",
-    "sourceCodeHash": "0x83188d878ce0b2890a7f7f41d09a8807f94a126e0ea274f0dac8b93f77217d3b"
+    "initCodeHash": "0xf85225ea25a87ba670b6ce0172a4814fda712d1c8a174fd4e8ce72b1cebcc2a0",
+    "sourceCodeHash": "0x66b56c0ac0d49b6da84da01a318f43418ef486e5fb40ae0af487568fde8566fb"
   },
   "src/L2/SuperchainWETH.sol": {
     "initCodeHash": "0x5db03c5c4cd6ea9e4b3e74e28f50d04fd3e130af5109b34fa208808fa9ba7742",

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

@@ -30,7 +30,7 @@
         "type": "uint256"
       }
     ],
-    "name": "__superchainBurn",
+    "name": "__crosschainBurn",
     "outputs": [],
     "stateMutability": "nonpayable",
     "type": "function"
@@ -48,7 +48,7 @@
         "type": "uint256"
       }
     ],
-    "name": "__superchainMint",
+    "name": "__crosschainMint",
     "outputs": [],
     "stateMutability": "nonpayable",
     "type": "function"
@@ -440,19 +440,6 @@
     "name": "Burn",
     "type": "event"
   },
-  {
-    "anonymous": false,
-    "inputs": [
-      {
-        "indexed": false,
-        "internalType": "uint64",
-        "name": "version",
-        "type": "uint64"
-      }
-    ],
-    "name": "Initialized",
-    "type": "event"
-  },
   {
     "anonymous": false,
     "inputs": [
@@ -469,7 +456,7 @@
         "type": "uint256"
       }
     ],
-    "name": "Mint",
+    "name": "CrosschainBurnt",
     "type": "event"
   },
   {
@@ -488,7 +475,20 @@
         "type": "uint256"
       }
     ],
-    "name": "SuperchainBurnt",
+    "name": "CrosschainMinted",
+    "type": "event"
+  },
+  {
+    "anonymous": false,
+    "inputs": [
+      {
+        "indexed": false,
+        "internalType": "uint64",
+        "name": "version",
+        "type": "uint64"
+      }
+    ],
+    "name": "Initialized",
     "type": "event"
   },
   {
@@ -507,7 +507,7 @@
         "type": "uint256"
       }
     ],
-    "name": "SuperchainMinted",
+    "name": "Mint",
     "type": "event"
   },
   {

packages/contracts-bedrock/src/L2/SuperchainERC20.sol

@@ -1,7 +1,8 @@
 // SPDX-License-Identifier: MIT
 pragma solidity 0.8.25;
 
-import { ISuperchainERC20Extension } from "src/L2/interfaces/ISuperchainERC20.sol";
+import { ICrosschainERC20 } from "src/L2/interfaces/ICrosschainERC20.sol";
+import { ISuperchainERC20Errors } from "src/L2/interfaces/ISuperchainERC20.sol";
 import { ISemver } from "src/universal/interfaces/ISemver.sol";
 import { Predeploys } from "src/libraries/Predeploys.sol";
 import { ERC20 } from "@solady/tokens/ERC20.sol";
@@ -10,7 +11,7 @@ import { ERC20 } from "@solady/tokens/ERC20.sol";
 /// @notice SuperchainERC20 is a standard extension of the base ERC20 token contract that unifies ERC20 token
 ///         bridging to make it fungible across the Superchain. This construction allows the SuperchainERC20Bridge to
 ///         burn and mint tokens.
-abstract contract SuperchainERC20 is ERC20, ISuperchainERC20Extension, ISemver {
+abstract contract SuperchainERC20 is ERC20, ICrosschainERC20, ISuperchainERC20Errors, ISemver {
     /// @notice A modifier that only allows the SuperchainERC20Bridge to call
     modifier onlySuperchainERC20Bridge() {
         if (msg.sender != Predeploys.SUPERCHAIN_ERC20_BRIDGE) revert OnlySuperchainERC20Bridge();
@@ -26,18 +27,18 @@ abstract contract SuperchainERC20 is ERC20, ISuperchainERC20Extension, ISemver {
     /// @notice Allows the SuperchainERC20Bridge to mint tokens.
     /// @param _to     Address to mint tokens to.
     /// @param _amount Amount of tokens to mint.
-    function __superchainMint(address _to, uint256 _amount) external virtual onlySuperchainERC20Bridge {
+    function __crosschainMint(address _to, uint256 _amount) external virtual onlySuperchainERC20Bridge {
         _mint(_to, _amount);
 
-        emit SuperchainMinted(_to, _amount);
+        emit CrosschainMinted(_to, _amount);
     }
 
     /// @notice Allows the SuperchainERC20Bridge to burn tokens.
     /// @param _from   Address to burn tokens from.
     /// @param _amount Amount of tokens to burn.
-    function __superchainBurn(address _from, uint256 _amount) external virtual onlySuperchainERC20Bridge {
+    function __crosschainBurn(address _from, uint256 _amount) external virtual onlySuperchainERC20Bridge {
         _burn(_from, _amount);
 
-        emit SuperchainBurnt(_from, _amount);
+        emit CrosschainBurnt(_from, _amount);
     }
 }

packages/contracts-bedrock/src/L2/SuperchainERC20Bridge.sol

@@ -31,7 +31,7 @@ contract SuperchainERC20Bridge is ISuperchainERC20Bridge {
     function sendERC20(address _token, address _to, uint256 _amount, uint256 _chainId) external {
         if (_to == address(0)) revert ZeroAddress();
 
-        ISuperchainERC20(_token).__superchainBurn(msg.sender, _amount);
+        ISuperchainERC20(_token).__crosschainBurn(msg.sender, _amount);
 
         bytes memory message = abi.encodeCall(this.relayERC20, (_token, msg.sender, _to, _amount));
         IL2ToL2CrossDomainMessenger(MESSENGER).sendMessage(_chainId, address(this), message);
@@ -53,7 +53,7 @@ contract SuperchainERC20Bridge is ISuperchainERC20Bridge {
 
         uint256 source = IL2ToL2CrossDomainMessenger(MESSENGER).crossDomainMessageSource();
 
-        ISuperchainERC20(_token).__superchainMint(_to, _amount);
+        ISuperchainERC20(_token).__crosschainMint(_to, _amount);
 
         emit RelayERC20(_token, _from, _to, _amount, source);
     }

packages/contracts-bedrock/src/L2/interfaces/ICrosschainERC20.sol

@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
+
+/// @title ICrosschainERC20
+/// @notice This interface is a standard for crosschain ERC20 transfers.
+interface ICrosschainERC20 {
+    /// @notice Emitted whenever tokens are minted by a crosschain transfer.
+    /// @param account Address of the account tokens are being minted for.
+    /// @param amount  Amount of tokens minted.
+    event CrosschainMinted(address indexed account, uint256 amount);
+
+    /// @notice Emitted whenever tokens are burned by a crosschain transfer.
+    /// @param account Address of the account tokens are being burned from.
+    /// @param amount  Amount of tokens burned.
+    event CrosschainBurnt(address indexed account, uint256 amount);
+
+    /// @notice Allows to mint tokens through a crosschain transfer.
+    /// @param _to     Address to mint tokens to.
+    /// @param _amount Amount of tokens to mint.
+    function __crosschainMint(address _to, uint256 _amount) external;
+
+    /// @notice Allows to burn tokens through a crosschain transfer.
+    /// @param _from   Address to burn tokens from.
+    /// @param _amount Amount of tokens to burn.
+    function __crosschainBurn(address _from, uint256 _amount) external;
+}

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

@@ -2,7 +2,7 @@
 pragma solidity ^0.8.0;
 
 // Interfaces
-import { ISuperchainERC20, ISuperchainERC20Extension } from "src/L2/interfaces/ISuperchainERC20.sol";
+import { ISuperchainERC20Extension } from "src/L2/interfaces/ISuperchainERC20.sol";
 import { IERC20Solady } from "src/vendor/interfaces/IERC20Solady.sol";
 
 /// @title IOptimismSuperchainERC20Errors

packages/contracts-bedrock/src/L2/interfaces/ISuperchainERC20.sol

@@ -2,6 +2,7 @@
 pragma solidity ^0.8.0;
 
 // Interfaces
+import { ICrosschainERC20 } from "src/L2/interfaces/ICrosschainERC20.sol";
 import { IERC20Solady } from "src/vendor/interfaces/IERC20Solady.sol";
 
 /// @title ISuperchainERC20Errors
@@ -13,27 +14,7 @@ interface ISuperchainERC20Errors {
 
 /// @title ISuperchainERC20Extension
 /// @notice This interface is available on the SuperchainERC20 contract.
-interface ISuperchainERC20Extension is ISuperchainERC20Errors {
-    /// @notice Emitted whenever tokens are minted for by the SuperchainERC20Bridge.
-    /// @param account Address of the account tokens are being minted for.
-    /// @param amount  Amount of tokens minted.
-    event SuperchainMinted(address indexed account, uint256 amount);
-
-    /// @notice Emitted whenever tokens are burned by the SuperchainERC20Bridge.
-    /// @param account Address of the account tokens are being burned from.
-    /// @param amount  Amount of tokens burned.
-    event SuperchainBurnt(address indexed account, uint256 amount);
-
-    /// @notice Allows the SuperchainERC20Bridge to mint tokens.
-    /// @param _to     Address to mint tokens to.
-    /// @param _amount Amount of tokens to mint.
-    function __superchainMint(address _to, uint256 _amount) external;
-
-    /// @notice Allows the SuperchainERC20Bridge to burn tokens.
-    /// @param _from   Address to burn tokens from.
-    /// @param _amount Amount of tokens to burn.
-    function __superchainBurn(address _from, uint256 _amount) external;
-}
+interface ISuperchainERC20Extension is ICrosschainERC20, ISuperchainERC20Errors { }
 
 /// @title ISuperchainERC20
 /// @notice Combines Solady's ERC20 interface with the SuperchainERC20Extension interface.

packages/contracts-bedrock/test/L2/SuperchainERC20.t.sol

@@ -16,7 +16,8 @@ import { IBeacon } from "@openzeppelin/contracts-v5/proxy/beacon/IBeacon.sol";
 import { BeaconProxy } from "@openzeppelin/contracts-v5/proxy/beacon/BeaconProxy.sol";
 
 // Target contract
-import { SuperchainERC20, ISuperchainERC20Extension } from "src/L2/SuperchainERC20.sol";
+import { SuperchainERC20 } from "src/L2/SuperchainERC20.sol";
+import { ICrosschainERC20 } from "src/L2/interfaces/ICrosschainERC20.sol";
 import { ISuperchainERC20Errors } from "src/L2/interfaces/ISuperchainERC20.sol";
 import { SuperchainERC20Implementation_MockContract } from "test/mocks/SuperchainERC20Implementation.sol";
 
@@ -41,7 +42,7 @@ contract SuperchainERC20Test is Test {
     }
 
     /// @notice Tests the `mint` function reverts when the caller is not the bridge.
-    function testFuzz___superchainMint_callerNotBridge_reverts(address _caller, address _to, uint256 _amount) public {
+    function testFuzz___crosschainMint_callerNotBridge_reverts(address _caller, address _to, uint256 _amount) public {
         // Ensure the caller is not the bridge
         vm.assume(_caller != SUPERCHAIN_ERC20_BRIDGE);
 
@@ -50,11 +51,11 @@ contract SuperchainERC20Test is Test {
 
         // Call the `mint` function with the non-bridge caller
         vm.prank(_caller);
-        superchainERC20.__superchainMint(_to, _amount);
+        superchainERC20.__crosschainMint(_to, _amount);
     }
 
     /// @notice Tests the `mint` succeeds and emits the `Mint` event.
-    function testFuzz___superchainMint_succeeds(address _to, uint256 _amount) public {
+    function testFuzz___crosschainMint_succeeds(address _to, uint256 _amount) public {
         // Ensure `_to` is not the zero address
         vm.assume(_to != ZERO_ADDRESS);
 
@@ -66,21 +67,21 @@ contract SuperchainERC20Test is Test {
         vm.expectEmit(address(superchainERC20));
         emit IERC20.Transfer(ZERO_ADDRESS, _to, _amount);
 
-        // Look for the emit of the `SuperchainMinted` event
+        // Look for the emit of the `CrosschainMinted` event
         vm.expectEmit(address(superchainERC20));
-        emit ISuperchainERC20Extension.SuperchainMinted(_to, _amount);
+        emit ICrosschainERC20.CrosschainMinted(_to, _amount);
 
         // Call the `mint` function with the bridge caller
         vm.prank(SUPERCHAIN_ERC20_BRIDGE);
-        superchainERC20.__superchainMint(_to, _amount);
+        superchainERC20.__crosschainMint(_to, _amount);
 
         // Check the total supply and balance of `_to` after the mint were updated correctly
         assertEq(superchainERC20.totalSupply(), _totalSupplyBefore + _amount);
         assertEq(superchainERC20.balanceOf(_to), _toBalanceBefore + _amount);
     }
 
     /// @notice Tests the `burn` function reverts when the caller is not the bridge.
-    function testFuzz___superchainBurn_callerNotBridge_reverts(
+    function testFuzz___crosschainBurn_callerNotBridge_reverts(
         address _caller,
         address _from,
         uint256 _amount
@@ -95,17 +96,17 @@ contract SuperchainERC20Test is Test {
 
         // Call the `burn` function with the non-bridge caller
         vm.prank(_caller);
-        superchainERC20.__superchainBurn(_from, _amount);
+        superchainERC20.__crosschainBurn(_from, _amount);
     }
 
-    /// @notice Tests the `burn` burns the amount and emits the `SuperchainBurnt` event.
-    function testFuzz___superchainBurn_succeeds(address _from, uint256 _amount) public {
+    /// @notice Tests the `burn` burns the amount and emits the `CrosschainBurnt` event.
+    function testFuzz___crosschainBurn_succeeds(address _from, uint256 _amount) public {
         // Ensure `_from` is not the zero address
         vm.assume(_from != ZERO_ADDRESS);
 
         // Mint some tokens to `_from` so then they can be burned
         vm.prank(SUPERCHAIN_ERC20_BRIDGE);
-        superchainERC20.__superchainMint(_from, _amount);
+        superchainERC20.__crosschainMint(_from, _amount);
 
         // Get the total supply and balance of `_from` before the burn to compare later on the assertions
         uint256 _totalSupplyBefore = superchainERC20.totalSupply();
@@ -115,13 +116,13 @@ contract SuperchainERC20Test is Test {
         vm.expectEmit(address(superchainERC20));
         emit IERC20.Transfer(_from, ZERO_ADDRESS, _amount);
 
-        // Look for the emit of the `SuperchainBurnt` event
+        // Look for the emit of the `CrosschainBurnt` event
         vm.expectEmit(address(superchainERC20));
-        emit ISuperchainERC20Extension.SuperchainBurnt(_from, _amount);
+        emit ICrosschainERC20.CrosschainBurnt(_from, _amount);
 
         // Call the `burn` function with the bridge caller
         vm.prank(SUPERCHAIN_ERC20_BRIDGE);
-        superchainERC20.__superchainBurn(_from, _amount);
+        superchainERC20.__crosschainBurn(_from, _amount);
 
         // Check the total supply and balance of `_from` after the burn were updated correctly
         assertEq(superchainERC20.totalSupply(), _totalSupplyBefore - _amount);

packages/contracts-bedrock/test/L2/SuperchainERC20Bridge.t.sol

@@ -67,7 +67,7 @@ contract SuperchainERC20BridgeTest is Bridge_Initializer {
 
         // Mint some tokens to the sender so then they can be sent
         vm.prank(Predeploys.SUPERCHAIN_ERC20_BRIDGE);
-        superchainERC20.__superchainMint(_sender, _amount);
+        superchainERC20.__crosschainMint(_sender, _amount);
 
         // Get the total supply and balance of `_sender` before the send to compare later on the assertions
         uint256 _totalSupplyBefore = superchainERC20.totalSupply();

packages/contracts-bedrock/test/invariants/OptimismSuperchainERC20/fuzz/Protocol.unguided.t.sol

@@ -17,7 +17,7 @@ contract ProtocolUnguided is ProtocolHandler, CompatibleAssert {
         bytes32 salt = MESSENGER.superTokenInitDeploySalts(token);
         amount = bound(amount, 0, type(uint256).max - OptimismSuperchainERC20(token).totalSupply());
         vm.prank(sender);
-        try OptimismSuperchainERC20(token).__superchainMint(to, amount) {
+        try OptimismSuperchainERC20(token).__crosschainMint(to, amount) {
             compatibleAssert(sender == BRIDGE);
             (, uint256 currentValue) = ghost_totalSupplyAcrossChains.tryGet(salt);
             ghost_totalSupplyAcrossChains.set(salt, currentValue + amount);
@@ -33,7 +33,7 @@ contract ProtocolUnguided is ProtocolHandler, CompatibleAssert {
         bytes32 salt = MESSENGER.superTokenInitDeploySalts(token);
         uint256 senderBalance = OptimismSuperchainERC20(token).balanceOf(sender);
         vm.prank(sender);
-        try OptimismSuperchainERC20(token).__superchainBurn(from, amount) {
+        try OptimismSuperchainERC20(token).__crosschainBurn(from, amount) {
             compatibleAssert(sender == BRIDGE);
             (, uint256 currentValue) = ghost_totalSupplyAcrossChains.tryGet(salt);
             ghost_totalSupplyAcrossChains.set(salt, currentValue - amount);

packages/contracts-bedrock/test/invariants/OptimismSuperchainERC20/handlers/Protocol.t.sol

@@ -79,7 +79,7 @@ contract ProtocolHandler is TestBase, StdUtils, Actors {
         index = bound(index, 0, allSuperTokens.length - 1);
         address addr = allSuperTokens[index];
         vm.prank(BRIDGE);
-        OptimismSuperchainERC20(addr).__superchainMint(currentActor(), amount);
+        OptimismSuperchainERC20(addr).__crosschainMint(currentActor(), amount);
         // currentValue will be zero if key is not present
         (, uint256 currentValue) = ghost_totalSupplyAcrossChains.tryGet(MESSENGER.superTokenInitDeploySalts(addr));
         ghost_totalSupplyAcrossChains.set(MESSENGER.superTokenInitDeploySalts(addr), currentValue + amount);