remove CGT code (#13686)

* remove CGT code

* fixes

* fixes

* remove CGT code

* fixes

* fixes

* restore L2 tests

* make _balance a spacer, inline unnecessary internal function

* add version tests

* add version tests

* add version tests

* add version tests

* ...

* fixes

* fixes

packages/contracts-bedrock/interfaces/L1/IOptimismPortal2.sol

@@ -9,7 +9,6 @@ import { ISystemConfig } from "interfaces/L1/ISystemConfig.sol";
 import { ISuperchainConfig } from "interfaces/L1/ISuperchainConfig.sol";
 
 interface IOptimismPortal2 {
-    error CustomGasTokenNotSupported();
     error AlreadyFinalized();
     error BadTarget();
     error Blacklisted();
@@ -24,13 +23,10 @@ interface IOptimismPortal2 {
     error InvalidMerkleProof();
     error InvalidProof();
     error LargeCalldata();
-    error NoValue();
     error NonReentrant();
-    error OnlyCustomGasToken();
     error OutOfGas();
     error ProposalNotValidated();
     error SmallGasLimit();
-    error TransferFailed();
     error Unauthorized();
     error UnexpectedList();
     error UnexpectedString();
@@ -46,18 +42,8 @@ interface IOptimismPortal2 {
 
     receive() external payable;
 
-    function balance() external view returns (uint256);
     function blacklistDisputeGame(IDisputeGame _disputeGame) external;
     function checkWithdrawal(bytes32 _withdrawalHash, address _proofSubmitter) external view;
-    function depositERC20Transaction(
-        address _to,
-        uint256 _mint,
-        uint256 _value,
-        uint64 _gasLimit,
-        bool _isCreation,
-        bytes memory _data
-    )
-        external;
     function depositTransaction(
         address _to,
         uint256 _value,
@@ -109,7 +95,6 @@ interface IOptimismPortal2 {
         returns (IDisputeGame disputeGameProxy, uint64 timestamp); // nosemgrep
     function respectedGameType() external view returns (GameType);
     function respectedGameTypeUpdatedAt() external view returns (uint64);
-    function setGasPayingToken(address _token, uint8 _decimals, bytes32 _name, bytes32 _symbol) external;
     function setRespectedGameType(GameType _gameType) external;
     function superchainConfig() external view returns (ISuperchainConfig);
     function systemConfig() external view returns (ISystemConfig);

packages/contracts-bedrock/interfaces/L1/IOptimismPortalInterop.sol

@@ -25,13 +25,10 @@ interface IOptimismPortalInterop {
     error InvalidMerkleProof();
     error InvalidProof();
     error LargeCalldata();
-    error NoValue();
     error NonReentrant();
-    error OnlyCustomGasToken();
     error OutOfGas();
     error ProposalNotValidated();
     error SmallGasLimit();
-    error TransferFailed();
     error Unauthorized();
     error UnexpectedList();
     error UnexpectedString();
@@ -47,18 +44,8 @@ interface IOptimismPortalInterop {
 
     receive() external payable;
 
-    function balance() external view returns (uint256);
     function blacklistDisputeGame(IDisputeGame _disputeGame) external;
     function checkWithdrawal(bytes32 _withdrawalHash, address _proofSubmitter) external view;
-    function depositERC20Transaction(
-        address _to,
-        uint256 _mint,
-        uint256 _value,
-        uint64 _gasLimit,
-        bool _isCreation,
-        bytes memory _data
-    )
-        external;
     function depositTransaction(
         address _to,
         uint256 _value,
@@ -111,7 +98,6 @@ interface IOptimismPortalInterop {
     function respectedGameType() external view returns (GameType);
     function respectedGameTypeUpdatedAt() external view returns (uint64);
     function setConfig(ConfigType _type, bytes memory _value) external;
-    function setGasPayingToken(address _token, uint8 _decimals, bytes32 _name, bytes32 _symbol) external;
     function setRespectedGameType(GameType _gameType) external;
     function superchainConfig() external view returns (ISuperchainConfig);
     function systemConfig() external view returns (ISystemConfig);

packages/contracts-bedrock/interfaces/L1/ISystemConfig.sol

@@ -5,8 +5,6 @@ import { IResourceMetering } from "interfaces/L1/IResourceMetering.sol";
 
 /// @notice This interface corresponds to the Custom Gas Token version of the SystemConfig contract.
 interface ISystemConfig {
-    error CustomGasTokenNotSupported();
-
     enum UpdateType {
         BATCHER,
         FEE_SCALARS,
@@ -22,7 +20,6 @@ interface ISystemConfig {
         address disputeGameFactory;
         address optimismPortal;
         address optimismMintableERC20Factory;
-        address gasPayingToken;
     }
 
     event ConfigUpdate(uint256 indexed version, UpdateType indexed updateType, bytes data);
@@ -47,9 +44,6 @@ interface ISystemConfig {
     function gasLimit() external view returns (uint64);
     function eip1559Denominator() external view returns (uint32);
     function eip1559Elasticity() external view returns (uint32);
-    function gasPayingToken() external view returns (address addr_, uint8 decimals_);
-    function gasPayingTokenName() external view returns (string memory name_);
-    function gasPayingTokenSymbol() external view returns (string memory symbol_);
     function initialize(
         address _owner,
         uint32 _basefeeScalar,
@@ -62,7 +56,6 @@ interface ISystemConfig {
         Addresses memory _addresses
     )
         external;
-    function isCustomGasToken() external view returns (bool);
     function l1CrossDomainMessenger() external view returns (address addr_);
     function l1ERC721Bridge() external view returns (address addr_);
     function l1StandardBridge() external view returns (address addr_);

packages/contracts-bedrock/interfaces/L1/ISystemConfigInterop.sol

@@ -5,8 +5,6 @@ import { ISystemConfig } from "interfaces/L1/ISystemConfig.sol";
 import { IResourceMetering } from "interfaces/L1/IResourceMetering.sol";
 
 interface ISystemConfigInterop {
-    error CustomGasTokenNotSupported();
-
     event ConfigUpdate(uint256 indexed version, ISystemConfig.UpdateType indexed updateType, bytes data);
     event Initialized(uint8 version);
     event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
@@ -29,10 +27,6 @@ interface ISystemConfigInterop {
     function gasLimit() external view returns (uint64);
     function eip1559Denominator() external view returns (uint32);
     function eip1559Elasticity() external view returns (uint32);
-    function gasPayingToken() external view returns (address addr_, uint8 decimals_);
-    function gasPayingTokenName() external view returns (string memory name_);
-    function gasPayingTokenSymbol() external view returns (string memory symbol_);
-    function isCustomGasToken() external view returns (bool);
     function l1CrossDomainMessenger() external view returns (address addr_);
     function l1ERC721Bridge() external view returns (address addr_);
     function l1StandardBridge() external view returns (address addr_);

packages/contracts-bedrock/scripts/deploy/Deploy.s.sol

@@ -530,8 +530,7 @@ contract Deploy is Deployer {
                         l1StandardBridge: artifacts.mustGetAddress("L1StandardBridgeProxy"),
                         disputeGameFactory: artifacts.mustGetAddress("DisputeGameFactoryProxy"),
                         optimismPortal: artifacts.mustGetAddress("OptimismPortalProxy"),
-                        optimismMintableERC20Factory: artifacts.mustGetAddress("OptimismMintableERC20FactoryProxy"),
-                        gasPayingToken: customGasTokenAddress
+                        optimismMintableERC20Factory: artifacts.mustGetAddress("OptimismMintableERC20FactoryProxy")
                     })
                 )
             )

packages/contracts-bedrock/scripts/deploy/DeployOPChain.s.sol

@@ -563,8 +563,6 @@ contract DeployOPChain is Script {
             systemConfig.optimismMintableERC20Factory() == address(_doo.optimismMintableERC20FactoryProxy()),
             "SYSCON-210"
         );
-        (address gasPayingToken,) = systemConfig.gasPayingToken();
-        require(gasPayingToken == Constants.ETHER, "SYSCON-220");
     }
 
     function assertValidL1CrossDomainMessenger(DeployOPChainInput _doi, DeployOPChainOutput _doo) internal {

packages/contracts-bedrock/snapshots/.gas-snapshot

@@ -4,10 +4,10 @@ GasBenchMark_L1BlockInterop_SetValuesInterop:test_setL1BlockValuesInterop_benchm
 GasBenchMark_L1BlockInterop_SetValuesInterop_Warm:test_setL1BlockValuesInterop_benchmark() (gas: 5144)
 GasBenchMark_L1Block_SetValuesEcotone:test_setL1BlockValuesEcotone_benchmark() (gas: 158531)
 GasBenchMark_L1Block_SetValuesEcotone_Warm:test_setL1BlockValuesEcotone_benchmark() (gas: 7597)
-GasBenchMark_L1CrossDomainMessenger:test_sendMessage_benchmark_0() (gas: 369264)
-GasBenchMark_L1CrossDomainMessenger:test_sendMessage_benchmark_1() (gas: 2967493)
-GasBenchMark_L1StandardBridge_Deposit:test_depositERC20_benchmark_0() (gas: 564413)
-GasBenchMark_L1StandardBridge_Deposit:test_depositERC20_benchmark_1() (gas: 4076606)
-GasBenchMark_L1StandardBridge_Deposit:test_depositETH_benchmark_0() (gas: 467092)
-GasBenchMark_L1StandardBridge_Deposit:test_depositETH_benchmark_1() (gas: 3512819)
-GasBenchMark_L1StandardBridge_Finalize:test_finalizeETHWithdrawal_benchmark() (gas: 72667)
+GasBenchMark_L1CrossDomainMessenger:test_sendMessage_benchmark_0() (gas: 356487)
+GasBenchMark_L1CrossDomainMessenger:test_sendMessage_benchmark_1() (gas: 2954716)
+GasBenchMark_L1StandardBridge_Deposit:test_depositERC20_benchmark_0() (gas: 551636)
+GasBenchMark_L1StandardBridge_Deposit:test_depositERC20_benchmark_1() (gas: 4063829)
+GasBenchMark_L1StandardBridge_Deposit:test_depositETH_benchmark_0() (gas: 450322)
+GasBenchMark_L1StandardBridge_Deposit:test_depositETH_benchmark_1() (gas: 3496221)
+GasBenchMark_L1StandardBridge_Finalize:test_finalizeETHWithdrawal_benchmark() (gas: 59849)
\ No newline at end of file

packages/contracts-bedrock/snapshots/abi/OptimismPortal2.json

@@ -19,19 +19,6 @@
     "stateMutability": "payable",
     "type": "receive"
   },
-  {
-    "inputs": [],
-    "name": "balance",
-    "outputs": [
-      {
-        "internalType": "uint256",
-        "name": "",
-        "type": "uint256"
-      }
-    ],
-    "stateMutability": "view",
-    "type": "function"
-  },
   {
     "inputs": [
       {
@@ -63,44 +50,6 @@
     "stateMutability": "view",
     "type": "function"
   },
-  {
-    "inputs": [
-      {
-        "internalType": "address",
-        "name": "_to",
-        "type": "address"
-      },
-      {
-        "internalType": "uint256",
-        "name": "_mint",
-        "type": "uint256"
-      },
-      {
-        "internalType": "uint256",
-        "name": "_value",
-        "type": "uint256"
-      },
-      {
-        "internalType": "uint64",
-        "name": "_gasLimit",
-        "type": "uint64"
-      },
-      {
-        "internalType": "bool",
-        "name": "_isCreation",
-        "type": "bool"
-      },
-      {
-        "internalType": "bytes",
-        "name": "_data",
-        "type": "bytes"
-      }
-    ],
-    "name": "depositERC20Transaction",
-    "outputs": [],
-    "stateMutability": "nonpayable",
-    "type": "function"
-  },
   {
     "inputs": [
       {
@@ -602,34 +551,6 @@
     "stateMutability": "view",
     "type": "function"
   },
-  {
-    "inputs": [
-      {
-        "internalType": "address",
-        "name": "_token",
-        "type": "address"
-      },
-      {
-        "internalType": "uint8",
-        "name": "_decimals",
-        "type": "uint8"
-      },
-      {
-        "internalType": "bytes32",
-        "name": "_name",
-        "type": "bytes32"
-      },
-      {
-        "internalType": "bytes32",
-        "name": "_symbol",
-        "type": "bytes32"
-      }
-    ],
-    "name": "setGasPayingToken",
-    "outputs": [],
-    "stateMutability": "nonpayable",
-    "type": "function"
-  },
   {
     "inputs": [
       {
@@ -846,11 +767,6 @@
     "name": "ContentLengthMismatch",
     "type": "error"
   },
-  {
-    "inputs": [],
-    "name": "CustomGasTokenNotSupported",
-    "type": "error"
-  },
   {
     "inputs": [],
     "name": "EmptyItem",
@@ -896,21 +812,11 @@
     "name": "LargeCalldata",
     "type": "error"
   },
-  {
-    "inputs": [],
-    "name": "NoValue",
-    "type": "error"
-  },
   {
     "inputs": [],
     "name": "NonReentrant",
     "type": "error"
   },
-  {
-    "inputs": [],
-    "name": "OnlyCustomGasToken",
-    "type": "error"
-  },
   {
     "inputs": [],
     "name": "OutOfGas",
@@ -926,11 +832,6 @@
     "name": "SmallGasLimit",
     "type": "error"
   },
-  {
-    "inputs": [],
-    "name": "TransferFailed",
-    "type": "error"
-  },
   {
     "inputs": [],
     "name": "Unauthorized",

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

@@ -19,19 +19,6 @@
     "stateMutability": "payable",
     "type": "receive"
   },
-  {
-    "inputs": [],
-    "name": "balance",
-    "outputs": [
-      {
-        "internalType": "uint256",
-        "name": "",
-        "type": "uint256"
-      }
-    ],
-    "stateMutability": "view",
-    "type": "function"
-  },
   {
     "inputs": [
       {
@@ -63,44 +50,6 @@
     "stateMutability": "view",
     "type": "function"
   },
-  {
-    "inputs": [
-      {
-        "internalType": "address",
-        "name": "_to",
-        "type": "address"
-      },
-      {
-        "internalType": "uint256",
-        "name": "_mint",
-        "type": "uint256"
-      },
-      {
-        "internalType": "uint256",
-        "name": "_value",
-        "type": "uint256"
-      },
-      {
-        "internalType": "uint64",
-        "name": "_gasLimit",
-        "type": "uint64"
-      },
-      {
-        "internalType": "bool",
-        "name": "_isCreation",
-        "type": "bool"
-      },
-      {
-        "internalType": "bytes",
-        "name": "_data",
-        "type": "bytes"
-      }
-    ],
-    "name": "depositERC20Transaction",
-    "outputs": [],
-    "stateMutability": "nonpayable",
-    "type": "function"
-  },
   {
     "inputs": [
       {
@@ -620,34 +569,6 @@
     "stateMutability": "nonpayable",
     "type": "function"
   },
-  {
-    "inputs": [
-      {
-        "internalType": "address",
-        "name": "_token",
-        "type": "address"
-      },
-      {
-        "internalType": "uint8",
-        "name": "_decimals",
-        "type": "uint8"
-      },
-      {
-        "internalType": "bytes32",
-        "name": "_name",
-        "type": "bytes32"
-      },
-      {
-        "internalType": "bytes32",
-        "name": "_symbol",
-        "type": "bytes32"
-      }
-    ],
-    "name": "setGasPayingToken",
-    "outputs": [],
-    "stateMutability": "nonpayable",
-    "type": "function"
-  },
   {
     "inputs": [
       {
@@ -914,21 +835,11 @@
     "name": "LargeCalldata",
     "type": "error"
   },
-  {
-    "inputs": [],
-    "name": "NoValue",
-    "type": "error"
-  },
   {
     "inputs": [],
     "name": "NonReentrant",
     "type": "error"
   },
-  {
-    "inputs": [],
-    "name": "OnlyCustomGasToken",
-    "type": "error"
-  },
   {
     "inputs": [],
     "name": "OutOfGas",
@@ -944,11 +855,6 @@
     "name": "SmallGasLimit",
     "type": "error"
   },
-  {
-    "inputs": [],
-    "name": "TransferFailed",
-    "type": "error"
-  },
   {
     "inputs": [],
     "name": "Unauthorized",

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

@@ -238,50 +238,6 @@
     "stateMutability": "view",
     "type": "function"
   },
-  {
-    "inputs": [],
-    "name": "gasPayingToken",
-    "outputs": [
-      {
-        "internalType": "address",
-        "name": "addr_",
-        "type": "address"
-      },
-      {
-        "internalType": "uint8",
-        "name": "decimals_",
-        "type": "uint8"
-      }
-    ],
-    "stateMutability": "view",
-    "type": "function"
-  },
-  {
-    "inputs": [],
-    "name": "gasPayingTokenName",
-    "outputs": [
-      {
-        "internalType": "string",
-        "name": "name_",
-        "type": "string"
-      }
-    ],
-    "stateMutability": "view",
-    "type": "function"
-  },
-  {
-    "inputs": [],
-    "name": "gasPayingTokenSymbol",
-    "outputs": [
-      {
-        "internalType": "string",
-        "name": "symbol_",
-        "type": "string"
-      }
-    ],
-    "stateMutability": "view",
-    "type": "function"
-  },
   {
     "inputs": [
       {
@@ -387,11 +343,6 @@
             "internalType": "address",
             "name": "optimismMintableERC20Factory",
             "type": "address"
-          },
-          {
-            "internalType": "address",
-            "name": "gasPayingToken",
-            "type": "address"
           }
         ],
         "internalType": "struct SystemConfig.Addresses",
@@ -404,19 +355,6 @@
     "stateMutability": "nonpayable",
     "type": "function"
   },
-  {
-    "inputs": [],
-    "name": "isCustomGasToken",
-    "outputs": [
-      {
-        "internalType": "bool",
-        "name": "",
-        "type": "bool"
-      }
-    ],
-    "stateMutability": "view",
-    "type": "function"
-  },
   {
     "inputs": [],
     "name": "l1CrossDomainMessenger",
@@ -800,10 +738,5 @@
     ],
     "name": "OwnershipTransferred",
     "type": "event"
-  },
-  {
-    "inputs": [],
-    "name": "CustomGasTokenNotSupported",
-    "type": "error"
   }
 ]
\ No newline at end of file

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

@@ -259,50 +259,6 @@
     "stateMutability": "view",
     "type": "function"
   },
-  {
-    "inputs": [],
-    "name": "gasPayingToken",
-    "outputs": [
-      {
-        "internalType": "address",
-        "name": "addr_",
-        "type": "address"
-      },
-      {
-        "internalType": "uint8",
-        "name": "decimals_",
-        "type": "uint8"
-      }
-    ],
-    "stateMutability": "view",
-    "type": "function"
-  },
-  {
-    "inputs": [],
-    "name": "gasPayingTokenName",
-    "outputs": [
-      {
-        "internalType": "string",
-        "name": "name_",
-        "type": "string"
-      }
-    ],
-    "stateMutability": "view",
-    "type": "function"
-  },
-  {
-    "inputs": [],
-    "name": "gasPayingTokenSymbol",
-    "outputs": [
-      {
-        "internalType": "string",
-        "name": "symbol_",
-        "type": "string"
-      }
-    ],
-    "stateMutability": "view",
-    "type": "function"
-  },
   {
     "inputs": [
       {
@@ -408,21 +364,11 @@
             "internalType": "address",
             "name": "optimismMintableERC20Factory",
             "type": "address"
-          },
-          {
-            "internalType": "address",
-            "name": "gasPayingToken",
-            "type": "address"
           }
         ],
         "internalType": "struct SystemConfig.Addresses",
         "name": "_addresses",
         "type": "tuple"
-      },
-      {
-        "internalType": "address",
-        "name": "_dependencyManager",
-        "type": "address"
       }
     ],
     "name": "initialize",
@@ -535,16 +481,16 @@
             "internalType": "address",
             "name": "optimismMintableERC20Factory",
             "type": "address"
-          },
-          {
-            "internalType": "address",
-            "name": "gasPayingToken",
-            "type": "address"
           }
         ],
         "internalType": "struct SystemConfig.Addresses",
         "name": "_addresses",
         "type": "tuple"
+      },
+      {
+        "internalType": "address",
+        "name": "_dependencyManager",
+        "type": "address"
       }
     ],
     "name": "initialize",
@@ -552,19 +498,6 @@
     "stateMutability": "nonpayable",
     "type": "function"
   },
-  {
-    "inputs": [],
-    "name": "isCustomGasToken",
-    "outputs": [
-      {
-        "internalType": "bool",
-        "name": "",
-        "type": "bool"
-      }
-    ],
-    "stateMutability": "view",
-    "type": "function"
-  },
   {
     "inputs": [],
     "name": "l1CrossDomainMessenger",
@@ -961,10 +894,5 @@
     ],
     "name": "OwnershipTransferred",
     "type": "event"
-  },
-  {
-    "inputs": [],
-    "name": "CustomGasTokenNotSupported",
-    "type": "error"
   }
 ]
\ No newline at end of file

packages/contracts-bedrock/snapshots/semver-lock.json

@@ -4,28 +4,28 @@
     "sourceCodeHash": "0xae49c741c8cd546981ab59b85b88e9fc1055c4fae085e7078d601b42464f86e6"
   },
   "src/L1/L1CrossDomainMessenger.sol": {
-    "initCodeHash": "0x192b98a93759f2044ee1ea56270cd203d4f16210c06be388f29b8c1114b9329d",
-    "sourceCodeHash": "0xfa18fb2e6ac73a143303b07735239a383ae84bd0d0042cceb8253f4784e07afb"
+    "initCodeHash": "0x4b045c9e0fcfa37838edf154e6e75be4a60406204eccf0d606dfd55da80d266d",
+    "sourceCodeHash": "0xc92887952f5108a770c3fee8a61c70f740a0a55c2e9ed0aebe266a7c53c71dc3"
   },
   "src/L1/L1ERC721Bridge.sol": {
     "initCodeHash": "0x280488bce8b4fb364740c59de14c423851902088f384e077bccc79b9df48528a",
     "sourceCodeHash": "0xe12b9e6c4e4ac2e2c9a03f07c7689f6bf2231922536072812cf1f37a5a276e73"
   },
   "src/L1/L1StandardBridge.sol": {
-    "initCodeHash": "0x7d7030359826f64714ef0c2a5198901812fb0a99e949f23fe54ccf87a0df2e67",
-    "sourceCodeHash": "0xa91b445bdc666a02ba18e3b91ba94b6d54bbe65da714002fc734814201319d57"
+    "initCodeHash": "0xe5f5ab77cc5586ecd94cc687b98f25d8fd7f9bb146a942653a2ec9be7e68f070",
+    "sourceCodeHash": "0x51f0876ab8410ce32838483f8f59ad6d1c5b4a368e47415b30e44baf291a394b"
   },
   "src/L1/OPContractsManager.sol": {
-    "initCodeHash": "0xe0c14a8fee7ad4c4e28a3ff6ca4e726721a6c3fea0a74ab7eac7ef07fe4da0ae",
-    "sourceCodeHash": "0xe0f5413e0a0a335016d773f02ef6bd25551416635981e83b7a4da601b9b65bc4"
+    "initCodeHash": "0x8bef0b53e7102491957d3ea12ff4857d735dada6af3ef122376bcf3f5489c9b9",
+    "sourceCodeHash": "0x819e5e9867e09d16346daf81cfc9c129bf9026308055d1fbb6623b4f8818e613"
   },
   "src/L1/OptimismPortal2.sol": {
-    "initCodeHash": "0x7e533474310583593c2d57d30fcd1ec11e1568dbaaf37a2dd28c5cc574068bac",
-    "sourceCodeHash": "0xe67f0c01c9c9ba67d279304f9db84eebeb2e93d9f2728fea95c7a194f0ae338a"
+    "initCodeHash": "0x2121a97875875150106a54a71c6c4c03afe90b3364e416be047f55fdeab57204",
+    "sourceCodeHash": "0x96e3de3ef0025a6def702eeb481acd2d2d88971fd418be657472f51a98029773"
   },
   "src/L1/OptimismPortalInterop.sol": {
-    "initCodeHash": "0x917b3b31a149b5aab96539208f4810d207875f6f2563a45c50ed13a7940066c0",
-    "sourceCodeHash": "0xae2fbe02c0f8685692babeed0252ae8a624dc6d3bfb082fc3807d7b84869004b"
+    "initCodeHash": "0x09ffe45f91bf59315b9fd4a2941b819ed8b1bb0d8643a630c6193bd67acea0ed",
+    "sourceCodeHash": "0xbb6acc3e88af9594ffcb8a2f30860511b76e09024330e70052316668fe55fd1f"
   },
   "src/L1/ProtocolVersions.sol": {
     "initCodeHash": "0x0000ec89712d8b4609873f1ba76afffd4205bf9110818995c90134dbec12e91e",
@@ -36,12 +36,12 @@
     "sourceCodeHash": "0xafa784ea78818a382ff3a61e2d84be58c7978110c06b9273db68c0213ead02d3"
   },
   "src/L1/SystemConfig.sol": {
-    "initCodeHash": "0xbb18eef17cdc1d0d307b0241e818820063e3ce3c7021ea3bb3a85ff6e79659e1",
-    "sourceCodeHash": "0x5d6a9ef41fed54479f742345368e693ec1fcabdb60118081c03fe9da3a5d27ed"
+    "initCodeHash": "0xf0bfbb889687af7d4e006f40b269bbd9e4d967cdd9c1f29900017ff11b1f5095",
+    "sourceCodeHash": "0x2dde897735c0cd699f15a1927bf6f75c2da220c1934021ee93315708d5b5f995"
   },
   "src/L1/SystemConfigInterop.sol": {
-    "initCodeHash": "0x0d61e2a95122417e9bf074a8fc0bce6f2b03268985d09580a83099dc9016c72d",
-    "sourceCodeHash": "0x673ec83b89680b44945af89229b286f26df07a5938d497df5def47872d331cf3"
+    "initCodeHash": "0xd89526ba331c24f8ca5ce1eef1554ad573e3aa9e6845a5b0ec23ee8f3497a84a",
+    "sourceCodeHash": "0x10806bbaa0d0e1dca571b720bd9690dd55cbf57038ab5887ecfdce689b0ae94e"
   },
   "src/L2/BaseFeeVault.sol": {
     "initCodeHash": "0xc403d4c555d8e69a2699e01d192ae7327136701fa02da10a6d75a584b3c364c9",

packages/contracts-bedrock/snapshots/storageLayout/OptimismPortal2.json

@@ -120,7 +120,7 @@
   },
   {
     "bytes": "32",
-    "label": "_balance",
+    "label": "spacer_61_0_32",
     "offset": 0,
     "slot": "61",
     "type": "uint256"

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

@@ -120,7 +120,7 @@
   },
   {
     "bytes": "32",
-    "label": "_balance",
+    "label": "spacer_61_0_32",
     "offset": 0,
     "slot": "61",
     "type": "uint256"

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

@@ -6,6 +6,7 @@ import { CrossDomainMessenger } from "src/universal/CrossDomainMessenger.sol";
 
 // Libraries
 import { Predeploys } from "src/libraries/Predeploys.sol";
+import { Constants } from "src/libraries/Constants.sol";
 
 // Interfaces
 import { ISemver } from "interfaces/universal/ISemver.sol";
@@ -30,8 +31,8 @@ contract L1CrossDomainMessenger is CrossDomainMessenger, ISemver {
     ISystemConfig public systemConfig;
 
     /// @notice Semantic version.
-    /// @custom:semver 2.4.1-beta.5
-    string public constant version = "2.4.1-beta.5";
+    /// @custom:semver 2.4.1-beta.6
+    string public constant version = "2.4.1-beta.6";
 
     /// @notice Constructs the L1CrossDomainMessenger contract.
     constructor() {
@@ -57,8 +58,10 @@ contract L1CrossDomainMessenger is CrossDomainMessenger, ISemver {
     }
 
     /// @inheritdoc CrossDomainMessenger
-    function gasPayingToken() internal view override returns (address addr_, uint8 decimals_) {
-        (addr_, decimals_) = systemConfig.gasPayingToken();
+    /// @dev This is added to maintain compatibility with the CrossDomainMessenger abstract contract and should always
+    /// return the ether address and 18 decimals.
+    function gasPayingToken() internal pure override returns (address addr_, uint8 decimals_) {
+        return (Constants.ETHER, 18);
     }
 
     /// @notice Getter function for the OptimismPortal contract on this chain.

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

@@ -6,6 +6,7 @@ import { StandardBridge } from "src/universal/StandardBridge.sol";
 
 // Libraries
 import { Predeploys } from "src/libraries/Predeploys.sol";
+import { Constants } from "src/libraries/Constants.sol";
 
 // Interfaces
 import { ISemver } from "interfaces/universal/ISemver.sol";
@@ -75,8 +76,8 @@ contract L1StandardBridge is StandardBridge, ISemver {
     );
 
     /// @notice Semantic version.
-    /// @custom:semver 2.2.1-beta.5
-    string public constant version = "2.2.1-beta.5";
+    /// @custom:semver 2.2.1-beta.6
+    string public constant version = "2.2.1-beta.6";
 
     /// @notice Address of the SuperchainConfig contract.
     ISuperchainConfig public superchainConfig;
@@ -119,8 +120,10 @@ contract L1StandardBridge is StandardBridge, ISemver {
     }
 
     /// @inheritdoc StandardBridge
-    function gasPayingToken() internal view override returns (address addr_, uint8 decimals_) {
-        (addr_, decimals_) = systemConfig.gasPayingToken();
+    /// @dev This is added to maintain compatibility with the CrossDomainMessenger abstract contract and should always
+    /// return the ether address and 18 decimals.
+    function gasPayingToken() internal pure override returns (address addr_, uint8 decimals_) {
+        return (Constants.ETHER, 18);
     }
 
     /// @custom:legacy

packages/contracts-bedrock/src/L1/OPContractsManager.sol

@@ -138,8 +138,8 @@ contract OPContractsManager is ISemver {
 
     // -------- Constants and Variables --------
 
-    /// @custom:semver 1.0.0-beta.28
-    string public constant version = "1.0.0-beta.28";
+    /// @custom:semver 1.0.0-beta.29
+    string public constant version = "1.0.0-beta.29";
 
     /// @notice Represents the interface version so consumers know how to decode the DeployOutput struct
     /// that's emitted in the `Deployed` event. Whenever that struct changes, a new version should be used.
@@ -750,8 +750,7 @@ contract OPContractsManager is ISemver {
             l1StandardBridge: address(_output.l1StandardBridgeProxy),
             disputeGameFactory: address(_output.disputeGameFactoryProxy),
             optimismPortal: address(_output.optimismPortalProxy),
-            optimismMintableERC20Factory: address(_output.optimismMintableERC20FactoryProxy),
-            gasPayingToken: Constants.ETHER
+            optimismMintableERC20Factory: address(_output.optimismMintableERC20FactoryProxy)
         });
 
         assertValidContractAddress(opChainAddrs_.l1CrossDomainMessenger);

packages/contracts-bedrock/src/L1/OptimismPortal2.sol

@@ -12,15 +12,11 @@ import { Constants } from "src/libraries/Constants.sol";
 import { Types } from "src/libraries/Types.sol";
 import { Hashing } from "src/libraries/Hashing.sol";
 import { SecureMerkleTrie } from "src/libraries/trie/SecureMerkleTrie.sol";
-import { Predeploys } from "src/libraries/Predeploys.sol";
 import { AddressAliasHelper } from "src/vendor/AddressAliasHelper.sol";
 import {
     BadTarget,
     LargeCalldata,
     SmallGasLimit,
-    TransferFailed,
-    OnlyCustomGasToken,
-    NoValue,
     Unauthorized,
     CallPaused,
     GasEstimation,
@@ -44,10 +40,6 @@ import { IResourceMetering } from "interfaces/L1/IResourceMetering.sol";
 import { ISuperchainConfig } from "interfaces/L1/ISuperchainConfig.sol";
 import { IDisputeGameFactory } from "interfaces/dispute/IDisputeGameFactory.sol";
 import { IDisputeGame } from "interfaces/dispute/IDisputeGame.sol";
-import { IL1Block } from "interfaces/L2/IL1Block.sol";
-
-/// @notice This is temporary. Error thrown when a chain uses a custom gas token.
-error CustomGasTokenNotSupported();
 
 /// @custom:proxied true
 /// @title OptimismPortal2
@@ -137,12 +129,10 @@ contract OptimismPortal2 is Initializable, ResourceMetering, ISemver {
     ///         proof submission should be used when finalizing a withdrawal.
     mapping(bytes32 => address[]) public proofSubmitters;
 
-    /// @notice Represents the amount of native asset minted in L2. This may not
-    ///         be 100% accurate due to the ability to send ether to the contract
-    ///         without triggering a deposit transaction. It also is used to prevent
-    ///         overflows for L2 account balances when custom gas tokens are used.
-    ///         It is not safe to trust `ERC20.balanceOf` as it may lie.
-    uint256 internal _balance;
+    /// @custom:legacy
+    /// @custom:spacer _balance
+    /// @notice Spacer taking up the legacy `_balance` slot.
+    uint256 private spacer_61_0_32;
 
     /// @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
@@ -186,9 +176,9 @@ contract OptimismPortal2 is Initializable, ResourceMetering, ISemver {
     }
 
     /// @notice Semantic version.
-    /// @custom:semver 3.11.0-beta.10
+    /// @custom:semver 3.11.0-beta.11
     function version() public pure virtual returns (string memory) {
-        return "3.11.0-beta.10";
+        return "3.11.0-beta.11";
     }
 
     /// @notice Constructs the OptimismPortal contract.
@@ -232,19 +222,6 @@ contract OptimismPortal2 is Initializable, ResourceMetering, ISemver {
         __ResourceMetering_init();
     }
 
-    /// @notice Getter for the balance of the contract.
-    function balance() public view returns (uint256) {
-        (address token,) = gasPayingToken();
-        if (token == Constants.ETHER) {
-            return address(this).balance;
-        } else {
-            // Temporary revert till we support custom gas tokens
-            if (true) revert CustomGasTokenNotSupported();
-
-            return _balance;
-        }
-    }
-
     /// @notice Getter function for the address of the guardian.
     ///         Public getter is legacy and will be removed in the future. Use `SuperchainConfig.guardian()` instead.
     /// @return Address of the guardian.
@@ -294,11 +271,6 @@ contract OptimismPortal2 is Initializable, ResourceMetering, ISemver {
         // Intentionally empty.
     }
 
-    /// @notice Returns the gas paying token and its decimals.
-    function gasPayingToken() internal view returns (address addr_, uint8 decimals_) {
-        (addr_, decimals_) = systemConfig.gasPayingToken();
-    }
-
     /// @notice Getter for the resource config.
     ///         Used internally by the ResourceMetering contract.
     ///         The SystemConfig is the source of truth for the resource config.
@@ -417,9 +389,6 @@ contract OptimismPortal2 is Initializable, ResourceMetering, ISemver {
         // Set the l2Sender so contracts know who triggered this withdrawal on L2.
         l2Sender = _tx.sender;
 
-        bool success;
-        (address token,) = gasPayingToken();
-        if (token == Constants.ETHER) {
         // Trigger the call to the target contract. We use a custom low level method
         // SafeCall.callWithMinGas to ensure two key properties
         //   1. Target contracts cannot force this call to run out of gas by returning a very large
@@ -427,43 +396,7 @@ contract OptimismPortal2 is Initializable, ResourceMetering, ISemver {
         //   2. The amount of gas provided to the execution context of the target is at least the
         //      gas limit specified by the user. If there is not enough gas in the current context
         //      to accomplish this, `callWithMinGas` will revert.
-            success = SafeCall.callWithMinGas(_tx.target, _tx.gasLimit, _tx.value, _tx.data);
-        } else {
-            // Temporary revert till we support custom gas tokens
-            if (true) revert CustomGasTokenNotSupported();
-
-            // Cannot call the token contract directly from the portal. This would allow an attacker
-            // to call approve from a withdrawal and drain the balance of the portal.
-            if (_tx.target == token) revert BadTarget();
-
-            // Only transfer value when a non zero value is specified. This saves gas in the case of
-            // using the standard bridge or arbitrary message passing.
-            if (_tx.value != 0) {
-                // Update the contracts internal accounting of the amount of native asset in L2.
-                _balance -= _tx.value;
-
-                // Read the balance of the target contract before the transfer so the consistency
-                // of the transfer can be checked afterwards.
-                uint256 startBalance = IERC20(token).balanceOf(address(this));
-
-                // Transfer the ERC20 balance to the target, accounting for non standard ERC20
-                // implementations that may not return a boolean. This reverts if the low level
-                // call is not successful.
-                IERC20(token).safeTransfer({ to: _tx.target, value: _tx.value });
-
-                // The balance must be transferred exactly.
-                if (IERC20(token).balanceOf(address(this)) != startBalance - _tx.value) {
-                    revert TransferFailed();
-                }
-            }
-
-            // Make a call to the target contract only if there is calldata.
-            if (_tx.data.length != 0) {
-                success = SafeCall.callWithMinGas(_tx.target, _tx.gasLimit, 0, _tx.data);
-            } else {
-                success = true;
-            }
-        }
+        bool success = SafeCall.callWithMinGas(_tx.target, _tx.gasLimit, _tx.value, _tx.data);
 
         // Reset the l2Sender back to the default value.
         l2Sender = Constants.DEFAULT_L2_SENDER;
@@ -480,58 +413,6 @@ contract OptimismPortal2 is Initializable, ResourceMetering, ISemver {
         }
     }
 
-    /// @notice Entrypoint to depositing an ERC20 token as a custom gas token.
-    ///         This function depends on a well formed ERC20 token. There are only
-    ///         so many checks that can be done on chain for this so it is assumed
-    ///         that chain operators will deploy chains with well formed ERC20 tokens.
-    /// @param _to         Target address on L2.
-    /// @param _mint       Units of ERC20 token to deposit into L2.
-    /// @param _value      Units of ERC20 token to send on L2 to the recipient.
-    /// @param _gasLimit   Amount of L2 gas to purchase by burning gas on L1.
-    /// @param _isCreation Whether or not the transaction is a contract creation.
-    /// @param _data       Data to trigger the recipient with.
-    function depositERC20Transaction(
-        address _to,
-        uint256 _mint,
-        uint256 _value,
-        uint64 _gasLimit,
-        bool _isCreation,
-        bytes memory _data
-    )
-        public
-        metered(_gasLimit)
-    {
-        // Temporary revert till we support custom gas tokens
-        if (true) revert CustomGasTokenNotSupported();
-
-        // Can only be called if an ERC20 token is used for gas paying on L2
-        (address token,) = gasPayingToken();
-        if (token == Constants.ETHER) revert OnlyCustomGasToken();
-
-        // Gives overflow protection for L2 account balances.
-        _balance += _mint;
-
-        // Get the balance of the portal before the transfer.
-        uint256 startBalance = IERC20(token).balanceOf(address(this));
-
-        // Take ownership of the token. It is assumed that the user has given the portal an approval.
-        IERC20(token).safeTransferFrom({ from: msg.sender, to: address(this), value: _mint });
-
-        // Double check that the portal now has the exact amount of token.
-        if (IERC20(token).balanceOf(address(this)) != startBalance + _mint) {
-            revert TransferFailed();
-        }
-
-        _depositTransaction({
-            _to: _to,
-            _mint: _mint,
-            _value: _value,
-            _gasLimit: _gasLimit,
-            _isCreation: _isCreation,
-            _data: _data
-        });
-    }
-
     /// @notice Accepts deposits of ETH and data, and emits a TransactionDeposited event for use in
     ///         deriving deposit transactions. Note that if a deposit is made by a contract, its
     ///         address will be aliased when retrieved using `tx.origin` or `msg.sender`. Consider
@@ -551,40 +432,6 @@ contract OptimismPortal2 is Initializable, ResourceMetering, ISemver {
         public
         payable
         metered(_gasLimit)
-    {
-        (address token,) = gasPayingToken();
-
-        // Temporary revert till we support custom gas tokens
-        if (token != Constants.ETHER) revert CustomGasTokenNotSupported();
-
-        if (token != Constants.ETHER && msg.value != 0) revert NoValue();
-
-        _depositTransaction({
-            _to: _to,
-            _mint: msg.value,
-            _value: _value,
-            _gasLimit: _gasLimit,
-            _isCreation: _isCreation,
-            _data: _data
-        });
-    }
-
-    /// @notice Common logic for creating deposit transactions.
-    /// @param _to         Target address on L2.
-    /// @param _mint       Units of asset to deposit into L2.
-    /// @param _value      Units of asset to send on L2 to the recipient.
-    /// @param _gasLimit   Amount of L2 gas to purchase by burning gas on L1.
-    /// @param _isCreation Whether or not the transaction is a contract creation.
-    /// @param _data       Data to trigger the recipient with.
-    function _depositTransaction(
-        address _to,
-        uint256 _mint,
-        uint256 _value,
-        uint64 _gasLimit,
-        bool _isCreation,
-        bytes memory _data
-    )
-        internal
     {
         // Just to be safe, make sure that people specify address(0) as the target when doing
         // contract creations.
@@ -609,41 +456,13 @@ contract OptimismPortal2 is Initializable, ResourceMetering, ISemver {
         // Compute the opaque data that will be emitted as part of the TransactionDeposited event.
         // We use opaque data so that we can update the TransactionDeposited event in the future
         // without breaking the current interface.
-        bytes memory opaqueData = abi.encodePacked(_mint, _value, _gasLimit, _isCreation, _data);
+        bytes memory opaqueData = abi.encodePacked(msg.value, _value, _gasLimit, _isCreation, _data);
 
         // Emit a TransactionDeposited event so that the rollup node can derive a deposit
         // transaction for this deposit.
         emit TransactionDeposited(from, _to, DEPOSIT_VERSION, opaqueData);
     }
 
-    /// @notice Sets the gas paying token for the L2 system. This token is used as the
-    ///         L2 native asset. Only the SystemConfig contract can call this function.
-    function setGasPayingToken(address _token, uint8 _decimals, bytes32 _name, bytes32 _symbol) external {
-        // Temporary revert till we support custom gas tokens
-        if (true) revert CustomGasTokenNotSupported();
-
-        if (msg.sender != address(systemConfig)) revert Unauthorized();
-
-        // Set L2 deposit gas as used without paying burning gas. Ensures that deposits cannot use too much L2 gas.
-        // This value must be large enough to cover the cost of calling `L1Block.setGasPayingToken`.
-        useGas(SYSTEM_DEPOSIT_GAS_LIMIT);
-
-        // Emit the special deposit transaction directly that sets the gas paying
-        // token in the L1Block predeploy contract.
-        emit TransactionDeposited(
-            Constants.DEPOSITOR_ACCOUNT,
-            Predeploys.L1_BLOCK_ATTRIBUTES,
-            DEPOSIT_VERSION,
-            abi.encodePacked(
-                uint256(0), // mint
-                uint256(0), // value
-                uint64(SYSTEM_DEPOSIT_GAS_LIMIT), // gasLimit
-                false, // isCreation,
-                abi.encodeCall(IL1Block.setGasPayingToken, (_token, _decimals, _name, _symbol))
-            )
-        );
-    }
-
     /// @notice Blacklists a dispute game. Should only be used in the event that a dispute game resolves incorrectly.
     /// @param _disputeGame Dispute game to blacklist.
     function blacklistDisputeGame(IDisputeGame _disputeGame) external {

packages/contracts-bedrock/src/L1/OptimismPortalInterop.sol

@@ -12,6 +12,9 @@ import { Unauthorized } from "src/libraries/PortalErrors.sol";
 // Interfaces
 import { IL1BlockInterop, ConfigType } from "interfaces/L2/IL1BlockInterop.sol";
 
+/// @notice Error thrown when attempting to use custom gas token specific actions.
+error CustomGasTokenNotSupported();
+
 /// @custom:proxied true
 /// @title OptimismPortalInterop
 /// @notice The OptimismPortal is a low-level contract responsible for passing messages between L1
@@ -25,9 +28,9 @@ contract OptimismPortalInterop is OptimismPortal2 {
         OptimismPortal2(_proofMaturityDelaySeconds, _disputeGameFinalityDelaySeconds)
     { }
 
-    /// @custom:semver +interop-beta.7
+    /// @custom:semver +interop-beta.8
     function version() public pure override returns (string memory) {
-        return string.concat(super.version(), "+interop-beta.7");
+        return string.concat(super.version(), "+interop-beta.8");
     }
 
     /// @notice Sets static configuration options for the L2 system.
@@ -35,6 +38,7 @@ contract OptimismPortalInterop is OptimismPortal2 {
     /// @param _value Encoded value of the configuration.
     function setConfig(ConfigType _type, bytes memory _value) external {
         if (msg.sender != address(systemConfig)) revert Unauthorized();
+        if (_type == ConfigType.SET_GAS_PAYING_TOKEN) revert CustomGasTokenNotSupported();
 
         // Set L2 deposit gas as used without paying burning gas. Ensures that deposits cannot use too much L2 gas.
         // This value must be large enough to cover the cost of calling `L1Block.setConfig`.

packages/contracts-bedrock/src/L1/SystemConfig.sol

@@ -3,27 +3,20 @@ pragma solidity 0.8.15;
 
 // Contracts
 import { OwnableUpgradeable } from "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
-import { ERC20 } from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
 
 // Libraries
 import { Storage } from "src/libraries/Storage.sol";
-import { Constants } from "src/libraries/Constants.sol";
-import { GasPayingToken, IGasToken } from "src/libraries/GasPayingToken.sol";
 
 // Interfaces
 import { ISemver } from "interfaces/universal/ISemver.sol";
-import { IOptimismPortal2 } from "interfaces/L1/IOptimismPortal2.sol";
 import { IResourceMetering } from "interfaces/L1/IResourceMetering.sol";
 
-/// @dev This is temporary. Error thrown when a chain uses a custom gas token.
-error CustomGasTokenNotSupported();
-
 /// @custom:proxied true
 /// @title SystemConfig
 /// @notice The SystemConfig contract is used to manage configuration of an Optimism network.
 ///         All configuration is stored on L1 and picked up by L2 as part of the derviation of
 ///         the L2 chain.
-contract SystemConfig is OwnableUpgradeable, ISemver, IGasToken {
+contract SystemConfig is OwnableUpgradeable, ISemver {
     /// @notice Enum representing different types of updates.
     /// @custom:value BATCHER              Represents an update to the batcher hash.
     /// @custom:value FEE_SCALARS          Represents an update to l1 data fee scalars.
@@ -48,7 +41,6 @@ contract SystemConfig is OwnableUpgradeable, ISemver, IGasToken {
         address disputeGameFactory;
         address optimismPortal;
         address optimismMintableERC20Factory;
-        address gasPayingToken;
     }
 
     /// @notice Version identifier, used for upgrades.
@@ -91,9 +83,6 @@ contract SystemConfig is OwnableUpgradeable, ISemver, IGasToken {
     bytes32 public constant DISPUTE_GAME_FACTORY_SLOT =
         bytes32(uint256(keccak256("systemconfig.disputegamefactory")) - 1);
 
-    /// @notice The number of decimals that the gas paying token has.
-    uint8 internal constant GAS_PAYING_TOKEN_DECIMALS = 18;
-
     /// @notice The maximum gas limit that can be set for L2 blocks. This limit is used to enforce that the blocks
     ///         on L2 are not too large to process and prove. Over time, this value can be increased as various
     ///         optimizations and improvements are made to the system at large.
@@ -140,9 +129,9 @@ contract SystemConfig is OwnableUpgradeable, ISemver, IGasToken {
     event ConfigUpdate(uint256 indexed version, UpdateType indexed updateType, bytes data);
 
     /// @notice Semantic version.
-    /// @custom:semver 2.3.0-beta.10
+    /// @custom:semver 2.3.0-beta.11
     function version() public pure virtual returns (string memory) {
-        return "2.3.0-beta.10";
+        return "2.3.0-beta.11";
     }
 
     /// @notice Constructs the SystemConfig contract.
@@ -197,7 +186,6 @@ contract SystemConfig is OwnableUpgradeable, ISemver, IGasToken {
         Storage.setAddress(OPTIMISM_MINTABLE_ERC20_FACTORY_SLOT, _addresses.optimismMintableERC20Factory);
 
         _setStartBlock();
-        _setGasPayingToken(_addresses.gasPayingToken);
 
         _setResourceConfig(_config);
     }
@@ -268,55 +256,6 @@ contract SystemConfig is OwnableUpgradeable, ISemver, IGasToken {
         startBlock_ = Storage.getUint(START_BLOCK_SLOT);
     }
 
-    /// @notice Getter for the gas paying asset address.
-    function gasPayingToken() public view returns (address addr_, uint8 decimals_) {
-        (addr_, decimals_) = GasPayingToken.getToken();
-    }
-
-    /// @notice Getter for custom gas token paying networks. Returns true if the
-    ///         network uses a custom gas token.
-    function isCustomGasToken() public view returns (bool) {
-        (address token,) = gasPayingToken();
-        return token != Constants.ETHER;
-    }
-
-    /// @notice Getter for the gas paying token name.
-    function gasPayingTokenName() external view returns (string memory name_) {
-        name_ = GasPayingToken.getName();
-    }
-
-    /// @notice Getter for the gas paying token symbol.
-    function gasPayingTokenSymbol() external view returns (string memory symbol_) {
-        symbol_ = GasPayingToken.getSymbol();
-    }
-
-    /// @notice Internal setter for the gas paying token address, includes validation.
-    ///         The token must not already be set and must be non zero and not the ether address
-    ///         to set the token address. This prevents the token address from being changed
-    ///         and makes it explicitly opt-in to use custom gas token.
-    /// @param _token Address of the gas paying token.
-    function _setGasPayingToken(address _token) internal virtual {
-        if (_token != address(0) && _token != Constants.ETHER && !isCustomGasToken()) {
-            // Temporary revert till we support custom gas tokens
-            if (true) revert CustomGasTokenNotSupported();
-
-            require(
-                ERC20(_token).decimals() == GAS_PAYING_TOKEN_DECIMALS, "SystemConfig: bad decimals of gas paying token"
-            );
-            bytes32 name = GasPayingToken.sanitize(ERC20(_token).name());
-            bytes32 symbol = GasPayingToken.sanitize(ERC20(_token).symbol());
-
-            // Set the gas paying token in storage and in the OptimismPortal.
-            GasPayingToken.set({ _token: _token, _decimals: GAS_PAYING_TOKEN_DECIMALS, _name: name, _symbol: symbol });
-            IOptimismPortal2(payable(optimismPortal())).setGasPayingToken({
-                _token: _token,
-                _decimals: GAS_PAYING_TOKEN_DECIMALS,
-                _name: name,
-                _symbol: symbol
-            });
-        }
-    }
-
     /// @notice Updates the unsafe block signer address. Can only be called by the owner.
     /// @param _unsafeBlockSigner New unsafe block signer address.
     function setUnsafeBlockSigner(address _unsafeBlockSigner) external onlyOwner {

packages/contracts-bedrock/src/L1/SystemConfigInterop.sol

@@ -2,12 +2,9 @@
 pragma solidity 0.8.15;
 
 // Contracts
-import { ERC20 } from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
 import { SystemConfig } from "src/L1/SystemConfig.sol";
 
 // Libraries
-import { Constants } from "src/libraries/Constants.sol";
-import { GasPayingToken } from "src/libraries/GasPayingToken.sol";
 import { StaticConfig } from "src/libraries/StaticConfig.sol";
 import { Storage } from "src/libraries/Storage.sol";
 
@@ -16,9 +13,6 @@ import { IOptimismPortalInterop as IOptimismPortal } from "interfaces/L1/IOptimi
 import { IResourceMetering } from "interfaces/L1/IResourceMetering.sol";
 import { ConfigType } from "interfaces/L2/IL1BlockInterop.sol";
 
-/// @dev This is temporary. Error thrown when a chain uses a custom gas token.
-error CustomGasTokenNotSupported();
-
 /// @custom:proxied true
 /// @title SystemConfigInterop
 /// @notice The SystemConfig contract is used to manage configuration of an Optimism network.
@@ -71,41 +65,9 @@ contract SystemConfigInterop is SystemConfig {
         Storage.setAddress(DEPENDENCY_MANAGER_SLOT, _dependencyManager);
     }
 
-    /// @custom:semver +interop-beta.9
+    /// @custom:semver +interop-beta.10
     function version() public pure override returns (string memory) {
-        return string.concat(super.version(), "+interop-beta.9");
-    }
-
-    /// @notice Internal setter for the gas paying token address, includes validation.
-    ///         The token must not already be set and must be non zero and not the ether address
-    ///         to set the token address. This prevents the token address from being changed
-    ///         and makes it explicitly opt-in to use custom gas token. Additionally,
-    ///         OptimismPortal's address must be non zero, since otherwise the call to set the
-    ///         config for the gas paying token to OptimismPortal will fail.
-    /// @param _token Address of the gas paying token.
-    function _setGasPayingToken(address _token) internal override {
-        if (_token != address(0) && _token != Constants.ETHER && !isCustomGasToken()) {
-            // Temporary revert till we support custom gas tokens
-            if (true) revert CustomGasTokenNotSupported();
-
-            require(
-                ERC20(_token).decimals() == GAS_PAYING_TOKEN_DECIMALS, "SystemConfig: bad decimals of gas paying token"
-            );
-            bytes32 name = GasPayingToken.sanitize(ERC20(_token).name());
-            bytes32 symbol = GasPayingToken.sanitize(ERC20(_token).symbol());
-
-            // Set the gas paying token in storage and in the OptimismPortal.
-            GasPayingToken.set({ _token: _token, _decimals: GAS_PAYING_TOKEN_DECIMALS, _name: name, _symbol: symbol });
-            IOptimismPortal(payable(optimismPortal())).setConfig(
-                ConfigType.SET_GAS_PAYING_TOKEN,
-                StaticConfig.encodeSetGasPayingToken({
-                    _token: _token,
-                    _decimals: GAS_PAYING_TOKEN_DECIMALS,
-                    _name: name,
-                    _symbol: symbol
-                })
-            );
-        }
+        return string.concat(super.version(), "+interop-beta.10");
     }
 
     /// @notice Adds a chain to the interop dependency set. Can only be called by the dependency manager.

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

@@ -697,147 +697,6 @@ contract L1CrossDomainMessenger_Test is CommonTest {
         assertTrue(l1CrossDomainMessenger.paused());
         assertEq(l1CrossDomainMessenger.paused(), superchainConfig.paused());
     }
-
-    /// @dev Temporary test that checks that correct calls to sendMessage when using a custom gas token revert with the
-    /// expected error.
-    /// @dev Should be removed when/if Custom Gas Token functionality is allowed again.
-    function test_sendMessage_customGasToken_reverts() external {
-        skipIfForkTest("Custom gas token is still supported on forked tests");
-
-        // Mock the gasPayingToken function to return a custom gas token
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(18))
-        );
-
-        vm.prank(alice);
-        vm.expectRevert(IOptimismPortal2.CustomGasTokenNotSupported.selector);
-        l1CrossDomainMessenger.sendMessage(recipient, hex"ff", uint32(100));
-    }
-
-    /// @dev Tests that sendMessage succeeds with a custom gas token when the call value is zero.
-    function test_sendMessage_customGasTokenButNoValue_succeeds() external {
-        vm.skip(true, "Custom gas token not supported");
-
-        // Mock the gasPayingToken function to return a custom gas token
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(18))
-        );
-
-        // deposit transaction on the optimism portal should be called
-        vm.expectCall(
-            address(optimismPortal2),
-            abi.encodeCall(
-                IOptimismPortal2.depositTransaction,
-                (
-                    Predeploys.L2_CROSS_DOMAIN_MESSENGER,
-                    0,
-                    l1CrossDomainMessenger.baseGas(hex"ff", 100),
-                    false,
-                    Encoding.encodeCrossDomainMessage(
-                        l1CrossDomainMessenger.messageNonce(), alice, recipient, 0, 100, hex"ff"
-                    )
-                )
-            )
-        );
-
-        // TransactionDeposited event
-        vm.expectEmit(address(optimismPortal2));
-        emitTransactionDeposited(
-            AddressAliasHelper.applyL1ToL2Alias(address(l1CrossDomainMessenger)),
-            Predeploys.L2_CROSS_DOMAIN_MESSENGER,
-            0,
-            0,
-            l1CrossDomainMessenger.baseGas(hex"ff", 100),
-            false,
-            Encoding.encodeCrossDomainMessage(l1CrossDomainMessenger.messageNonce(), alice, recipient, 0, 100, hex"ff")
-        );
-
-        // SentMessage event
-        vm.expectEmit(address(l1CrossDomainMessenger));
-        emit SentMessage(recipient, alice, hex"ff", l1CrossDomainMessenger.messageNonce(), 100);
-
-        // SentMessageExtension1 event
-        vm.expectEmit(address(l1CrossDomainMessenger));
-        emit SentMessageExtension1(alice, 0);
-
-        vm.prank(alice);
-        l1CrossDomainMessenger.sendMessage(recipient, hex"ff", uint32(100));
-    }
-
-    /// @dev Tests that the sendMessage reverts when call value is non-zero with custom gas token.
-    function test_sendMessage_customGasTokenWithValue_reverts() external {
-        // TODO(opcm upgrades): remove skip once upgrade path is implemented
-        skipIfForkTest("L1CrossDomainMessenger_Test: gas paying token functionality DNE on op mainnet");
-
-        // Mock the gasPayingToken function to return a custom gas token
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(2))
-        );
-
-        vm.expectRevert("CrossDomainMessenger: cannot send value with custom gas token");
-        l1CrossDomainMessenger.sendMessage{ value: 1 }(recipient, hex"aa", uint32(500_000));
-    }
-
-    /// @dev Tests that the relayMessage succeeds with a custom gas token when the call value is zero.
-    function test_relayMessage_customGasTokenAndNoValue_succeeds() external {
-        // TODO(opcm upgrades): remove skip once upgrade path is implemented
-        skipIfForkTest("L1CrossDomainMessenger_Test: gas paying token functionality DNE on op mainnet");
-
-        // Mock the gasPayingToken function to return a custom gas token
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(2))
-        );
-
-        address target = address(0xabcd);
-        address sender = Predeploys.L2_CROSS_DOMAIN_MESSENGER;
-
-        vm.expectCall(target, hex"1111");
-
-        // set the value of op.l2Sender() to be the L2 Cross Domain Messenger.
-        vm.store(address(optimismPortal2), bytes32(senderSlotIndex), bytes32(abi.encode(sender)));
-        vm.prank(address(optimismPortal2));
-
-        vm.expectEmit(address(l1CrossDomainMessenger));
-
-        bytes32 hash = Hashing.hashCrossDomainMessage(
-            Encoding.encodeVersionedNonce({ _nonce: 0, _version: 1 }), sender, target, 0, 0, hex"1111"
-        );
-
-        emit RelayedMessage(hash);
-
-        l1CrossDomainMessenger.relayMessage(
-            Encoding.encodeVersionedNonce({ _nonce: 0, _version: 1 }), // nonce
-            sender,
-            target,
-            0, // value
-            0,
-            hex"1111"
-        );
-
-        // the message hash is in the successfulMessages mapping
-        assertTrue(l1CrossDomainMessenger.successfulMessages(hash));
-        // it is not in the received messages mapping
-        assertEq(l1CrossDomainMessenger.failedMessages(hash), false);
-    }
-
-    /// @dev Tests that the relayMessage reverts when call value is non-zero with custom gas token.
-    ///      The L2CrossDomainMessenger contract cannot `sendMessage` with value when using a custom gas token.
-    function test_relayMessage_customGasTokenWithValue_reverts() external virtual {
-        // Mock the gasPayingToken function to return a custom gas token
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(2))
-        );
-        vm.expectRevert("CrossDomainMessenger: value must be zero unless message is from a system address");
-
-        l1CrossDomainMessenger.relayMessage{ value: 1 }(
-            Encoding.encodeVersionedNonce({ _nonce: 0, _version: 1 }),
-            address(0xabcd),
-            address(0xabcd),
-            1, // value
-            0,
-            hex"1111"
-        );
-    }
 }
 
 /// @dev A regression test against a reentrancy vulnerability in the CrossDomainMessenger contract, which

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

@@ -198,26 +198,6 @@ contract L1StandardBridge_Receive_Test is CommonTest {
     }
 }
 
-contract L1StandardBridge_Receive_TestFail is CommonTest {
-    /// @dev Tests receive function reverts with custom gas token.
-    function testFuzz_receive_customGasToken_reverts(uint256 _value) external {
-        // TODO(opcm upgrades): remove skip once upgrade path is implemented
-        skipIfForkTest("L1StandardBridge_Receive_TestFail: gas paying token functionality DNE on op mainnet");
-
-        vm.prank(alice, alice);
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(18))
-        );
-        vm.deal(alice, _value);
-        (bool success, bytes memory data) = address(l1StandardBridge).call{ value: _value }(hex"");
-        assertFalse(success);
-        assembly {
-            data := add(data, 0x04)
-        }
-        assertEq(abi.decode(data, (string)), "StandardBridge: cannot bridge ETH with custom gas token");
-    }
-}
-
 contract PreBridgeETH is CommonTest {
     /// @dev Asserts the expected calls and events for bridging ETH depending
     ///      on whether the bridge call is legacy or not.
@@ -307,19 +287,6 @@ contract L1StandardBridge_DepositETH_TestFail is CommonTest {
         vm.prank(alice);
         l1StandardBridge.depositETH{ value: 1 }(300, hex"");
     }
-
-    /// @dev Tests that depositing reverts with custom gas token.
-    function test_depositETH_customGasToken_reverts() external {
-        // TODO(opcm upgrades): remove skip once upgrade path is implemented
-        skipIfForkTest("L1StandardBridge_DepositETH_TestFail: gas paying token functionality DNE on op mainnet");
-
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(2))
-        );
-        vm.prank(alice, alice);
-        vm.expectRevert("StandardBridge: cannot bridge ETH with custom gas token");
-        l1StandardBridge.depositETH(50000, hex"dead");
-    }
 }
 
 contract L1StandardBridge_BridgeETH_Test is PreBridgeETH {
@@ -336,22 +303,6 @@ contract L1StandardBridge_BridgeETH_Test is PreBridgeETH {
     }
 }
 
-contract L1StandardBridge_BridgeETH_TestFail is PreBridgeETH {
-    /// @dev Tests that bridging eth reverts with custom gas token.
-    function test_bridgeETH_customGasToken_reverts() external {
-        // TODO(opcm upgrades): remove skip once upgrade path is implemented
-        skipIfForkTest("L1StandardBridge_BridgeETH_TestFail: gas paying token functionality DNE on op mainnet");
-
-        vm.prank(alice, alice);
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(2))
-        );
-        vm.expectRevert("StandardBridge: cannot bridge ETH with custom gas token");
-
-        l1StandardBridge.bridgeETH(50000, hex"dead");
-    }
-}
-
 contract PreBridgeETHTo is CommonTest {
     /// @dev Asserts the expected calls and events for bridging ETH to a different
     ///      address depending on whether the bridge call is legacy or not.
@@ -432,29 +383,6 @@ contract L1StandardBridge_DepositETHTo_Test is PreBridgeETHTo {
     }
 }
 
-contract L1StandardBridge_DepositETHTo_TestFail is CommonTest {
-    /// @dev Tests that depositETHTo reverts with custom gas token.
-    function testFuzz_depositETHTo_customGasToken_reverts(
-        uint256 _value,
-        address _to,
-        uint32 _minGasLimit,
-        bytes calldata _extraData
-    )
-        external
-    {
-        // TODO(opcm upgrades): remove skip once upgrade path is implemented
-        skipIfForkTest("L1StandardBridge_DepositETHTo_TestFail: gas paying token functionality DNE on op mainnet");
-
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(2))
-        );
-        vm.deal(address(this), _value);
-        vm.expectRevert("StandardBridge: cannot bridge ETH with custom gas token");
-
-        l1StandardBridge.depositETHTo{ value: _value }(_to, _minGasLimit, _extraData);
-    }
-}
-
 contract L1StandardBridge_BridgeETHTo_Test is PreBridgeETHTo {
     /// @dev Tests that bridging ETH to a different address succeeds.
     ///      Emits ETHDepositInitiated and ETHBridgeInitiated events.
@@ -469,28 +397,6 @@ contract L1StandardBridge_BridgeETHTo_Test is PreBridgeETHTo {
     }
 }
 
-contract L1StandardBridge_BridgeETHTo_TestFail is PreBridgeETHTo {
-    /// @dev Tests that bridging reverts with custom gas token.
-    function testFuzz_bridgeETHTo_customGasToken_reverts(
-        uint256 _value,
-        uint32 _minGasLimit,
-        bytes calldata _extraData
-    )
-        external
-    {
-        // TODO(opcm upgrades): remove skip once upgrade path is implemented
-        skipIfForkTest("L1StandardBridge_BridgeETHTo_TestFail: gas paying token functionality DNE on op mainnet");
-
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(2))
-        );
-        vm.deal(address(this), _value);
-        vm.expectRevert("StandardBridge: cannot bridge ETH with custom gas token");
-
-        l1StandardBridge.bridgeETHTo{ value: _value }(bob, _minGasLimit, _extraData);
-    }
-}
-
 contract L1StandardBridge_DepositERC20_Test is CommonTest {
     using stdStorage for StdStorage;
 
@@ -682,35 +588,6 @@ contract L1StandardBridge_FinalizeETHWithdrawal_Test is CommonTest {
     }
 }
 
-contract L1StandardBridge_FinalizeETHWithdrawal_TestFail is CommonTest {
-    /// @dev Tests that finalizeETHWithdrawal reverts with custom gas token.
-    function testFuzz_finalizeETHWithdrawal_customGasToken_reverts(
-        uint256 _value,
-        bytes calldata _extraData
-    )
-        external
-    {
-        // TODO(opcm upgrades): remove skip once upgrade path is implemented
-        skipIfForkTest(
-            "L1StandardBridge_FinalizeETHWithdrawal_TestFail: gas paying token functionality DNE on op mainnet"
-        );
-
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(2))
-        );
-        vm.mockCall(
-            address(l1StandardBridge.messenger()),
-            abi.encodeCall(ICrossDomainMessenger.xDomainMessageSender, ()),
-            abi.encode(address(l1StandardBridge.OTHER_BRIDGE()))
-        );
-        vm.deal(address(l1StandardBridge.messenger()), _value);
-        vm.prank(address(l1StandardBridge.messenger()));
-        vm.expectRevert("StandardBridge: cannot bridge ETH with custom gas token");
-
-        l1StandardBridge.finalizeETHWithdrawal{ value: _value }(alice, alice, _value, _extraData);
-    }
-}
-
 contract L1StandardBridge_FinalizeERC20Withdrawal_Test is CommonTest {
     using stdStorage for StdStorage;
 
@@ -796,26 +673,6 @@ contract L1StandardBridge_FinalizeBridgeETH_Test is CommonTest {
 }
 
 contract L1StandardBridge_FinalizeBridgeETH_TestFail is CommonTest {
-    /// @dev Tests that finalizing bridged reverts with custom gas token.
-    function testFuzz_finalizeBridgeETH_customGasToken_reverts(uint256 _value, bytes calldata _extraData) external {
-        // TODO(opcm upgrades): remove skip once upgrade path is implemented
-        skipIfForkTest("L1StandardBridge_FinalizeBridgeETH_TestFail: gas paying token functionality DNE on op mainnet");
-
-        vm.mockCall(
-            address(l1StandardBridge.messenger()),
-            abi.encodeCall(ICrossDomainMessenger.xDomainMessageSender, ()),
-            abi.encode(address(l1StandardBridge.OTHER_BRIDGE()))
-        );
-        vm.deal(address(l1CrossDomainMessenger), _value);
-        vm.prank(address(l1CrossDomainMessenger));
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(2))
-        );
-        vm.expectRevert("StandardBridge: cannot bridge ETH with custom gas token");
-
-        l1StandardBridge.finalizeBridgeETH{ value: _value }(alice, alice, _value, _extraData);
-    }
-
     /// @dev Tests that finalizing bridged ETH reverts if the amount is incorrect.
     function test_finalizeBridgeETH_incorrectValue_reverts() external {
         address messenger = address(l1StandardBridge.messenger());

packages/contracts-bedrock/test/L1/OptimismPortal2.t.sol

@@ -2,9 +2,7 @@
 pragma solidity 0.8.15;
 
 // Testing
-import { stdError } from "forge-std/Test.sol";
 import { VmSafe } from "forge-std/Vm.sol";
-import { MockERC20 } from "solmate/test/utils/mocks/MockERC20.sol";
 import { CommonTest } from "test/setup/CommonTest.sol";
 import { NextImpl } from "test/mocks/NextImpl.sol";
 import { EIP1967Helper } from "test/mocks/EIP1967Helper.sol";
@@ -16,8 +14,6 @@ import { SuperchainConfig } from "src/L1/SuperchainConfig.sol";
 import { Types } from "src/libraries/Types.sol";
 import { Hashing } from "src/libraries/Hashing.sol";
 import { Constants } from "src/libraries/Constants.sol";
-import { Predeploys } from "src/libraries/Predeploys.sol";
-import { GasPayingToken } from "src/libraries/GasPayingToken.sol";
 import { AddressAliasHelper } from "src/vendor/AddressAliasHelper.sol";
 import { EIP1967Helper } from "test/mocks/EIP1967Helper.sol";
 import "src/dispute/lib/Types.sol";
@@ -25,7 +21,6 @@ import "src/libraries/PortalErrors.sol";
 
 // Interfaces
 import { IResourceMetering } from "interfaces/L1/IResourceMetering.sol";
-import { IL1Block } from "interfaces/L2/IL1Block.sol";
 import { IOptimismPortal2 } from "interfaces/L1/IOptimismPortal2.sol";
 import { IDisputeGame } from "interfaces/dispute/IDisputeGame.sol";
 import { IFaultDisputeGame } from "interfaces/dispute/IFaultDisputeGame.sol";
@@ -39,6 +34,12 @@ contract OptimismPortal2_Test is CommonTest {
         depositor = makeAddr("depositor");
     }
 
+    /// @notice Tests that the version function returns a valid string. We avoid testing the
+    ///         specific value of the string as it changes frequently.
+    function test_version_succeeds() external view {
+        assert(bytes(optimismPortal2.version()).length > 0);
+    }
+
     /// @dev Tests that the constructor sets the correct values.
     /// @notice Marked virtual to be overridden in
     ///         test/kontrol/deployment/DeploymentSummary.t.sol
@@ -310,186 +311,6 @@ contract OptimismPortal2_Test is CommonTest {
         assertEq(address(optimismPortal2).balance, balanceBefore + _mint);
     }
 
-    /// @dev Temporary test that checks that correct calls to setGasPayingToken when using a custom gas token revert
-    /// with the expected error.
-    /// @dev Should be removed when/if Custom Gas Token functionality is allowed again.
-    function test_setGasPayingToken_customGasToken_reverts(
-        address _token,
-        uint8 _decimals,
-        bytes32 _name,
-        bytes32 _symbol
-    )
-        external
-    {
-        skipIfForkTest("Custom gas token is still supported on forked tests");
-
-        vm.expectRevert(IOptimismPortal2.CustomGasTokenNotSupported.selector);
-        optimismPortal2.setGasPayingToken({ _token: _token, _decimals: _decimals, _name: _name, _symbol: _symbol });
-    }
-
-    /// @dev Tests that the gas paying token can be set.
-    function testFuzz_setGasPayingToken_succeeds(
-        address _token,
-        uint8 _decimals,
-        bytes32 _name,
-        bytes32 _symbol
-    )
-        external
-    {
-        vm.skip(true, "Custom gas token not supported");
-
-        // TODO(opcm upgrades): remove skip once upgrade path is implemented
-        skipIfForkTest("OptimismPortal2_Test: gas paying token functionality DNE on op mainnet");
-
-        vm.expectEmit(address(optimismPortal2));
-        emit TransactionDeposited(
-            0xDeaDDEaDDeAdDeAdDEAdDEaddeAddEAdDEAd0001,
-            Predeploys.L1_BLOCK_ATTRIBUTES,
-            0,
-            abi.encodePacked(
-                uint256(0), // mint
-                uint256(0), // value
-                uint64(200_000), // gasLimit
-                false, // isCreation,
-                abi.encodeCall(IL1Block.setGasPayingToken, (_token, _decimals, _name, _symbol))
-            )
-        );
-
-        vm.prank(address(systemConfig));
-        optimismPortal2.setGasPayingToken({ _token: _token, _decimals: _decimals, _name: _name, _symbol: _symbol });
-    }
-
-    /// @notice Ensures that the deposit event is correct for the `setGasPayingToken`
-    ///         code path that manually emits a deposit transaction outside of the
-    ///         `depositTransaction` function. This is a simple differential test.
-    function test_setGasPayingToken_correctEvent_succeeds(
-        address _token,
-        string calldata _name,
-        string calldata _symbol
-    )
-        external
-    {
-        vm.skip(true, "Custom gas token not supported");
-
-        // TODO(opcm upgrades): remove skip once upgrade path is implemented
-        skipIfForkTest("OptimismPortal2_Test: gas paying token functionality DNE on op mainnet");
-
-        if (bytes(_name).length > 32) {
-            _name = _name[0:32];
-        }
-        if (bytes(_symbol).length > 32) {
-            _symbol = _symbol[0:32];
-        }
-
-        bytes32 name = GasPayingToken.sanitize(_name);
-        bytes32 symbol = GasPayingToken.sanitize(_symbol);
-
-        vm.recordLogs();
-
-        vm.deal(address(systemConfig), 100 ether);
-        vm.prank(address(systemConfig));
-        optimismPortal2.setGasPayingToken({ _token: _token, _decimals: 18, _name: name, _symbol: symbol });
-
-        vm.prank(Constants.DEPOSITOR_ACCOUNT, Constants.DEPOSITOR_ACCOUNT);
-        optimismPortal2.depositTransaction({
-            _to: Predeploys.L1_BLOCK_ATTRIBUTES,
-            _value: 0,
-            _gasLimit: 200_000,
-            _isCreation: false,
-            _data: abi.encodeCall(IL1Block.setGasPayingToken, (_token, 18, name, symbol))
-        });
-
-        VmSafe.Log[] memory logs = vm.getRecordedLogs();
-        assertEq(logs.length, 2);
-
-        VmSafe.Log memory systemPath = logs[0];
-        VmSafe.Log memory userPath = logs[1];
-
-        assertEq(systemPath.topics.length, 4);
-        assertEq(systemPath.topics.length, userPath.topics.length);
-        assertEq(systemPath.topics[0], userPath.topics[0]);
-        assertEq(systemPath.topics[1], userPath.topics[1]);
-        assertEq(systemPath.topics[2], userPath.topics[2]);
-        assertEq(systemPath.topics[3], userPath.topics[3]);
-        assertEq(systemPath.data, userPath.data);
-    }
-
-    /// @dev Tests that the gas paying token cannot be set by a non-system config.
-    function test_setGasPayingToken_notSystemConfig_fails(address _caller) external {
-        vm.skip(true, "Custom gas token not supported");
-
-        // TODO(opcm upgrades): remove skip once upgrade path is implemented
-        skipIfForkTest("OptimismPortal2_Test: gas paying token functionality DNE on op mainnet");
-
-        vm.assume(_caller != address(systemConfig));
-        vm.prank(_caller);
-        vm.expectRevert(Unauthorized.selector);
-        optimismPortal2.setGasPayingToken({ _token: address(0), _decimals: 0, _name: "", _symbol: "" });
-    }
-
-    /// @dev Temporary test that checks that correct calls to depositERC20Transaction when using a custom gas token
-    /// revert
-    /// with the expected error.
-    /// @dev Should be removed when/if Custom Gas Token functionality is allowed again.
-    function test_depositERC20Transaction_customGasToken_reverts() external {
-        skipIfForkTest("Custom gas token is still supported on forked tests");
-
-        vm.expectRevert(IOptimismPortal2.CustomGasTokenNotSupported.selector);
-        optimismPortal2.depositERC20Transaction(address(0), 0, 0, 0, false, "");
-    }
-
-    /// @dev Tests that `depositERC20Transaction` reverts when the gas paying token is ether.
-    function test_depositERC20Transaction_noCustomGasToken_reverts() external {
-        vm.skip(true, "Custom gas token not supported");
-
-        // TODO(opcm upgrades): remove skip once upgrade path is implemented
-        skipIfForkTest("OptimismPortal2_Test: gas paying token functionality DNE on op mainnet");
-
-        // Check that the gas paying token is set to ether
-        (address token,) = systemConfig.gasPayingToken();
-        assertEq(token, Constants.ETHER);
-
-        vm.expectRevert(OnlyCustomGasToken.selector);
-        optimismPortal2.depositERC20Transaction(address(0), 0, 0, 0, false, "");
-    }
-
-    function test_depositERC20Transaction_balanceOverflow_reverts() external {
-        vm.skip(true, "Custom gas token not supported");
-
-        // TODO(opcm upgrades): remove skip once upgrade path is implemented
-        skipIfForkTest("OptimismPortal2_Test: gas paying token functionality DNE on op mainnet");
-        vm.mockCall(address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(42), 18));
-
-        // The balance slot
-        vm.store(address(optimismPortal2), bytes32(uint256(61)), bytes32(type(uint256).max));
-        assertEq(optimismPortal2.balance(), type(uint256).max);
-
-        vm.expectRevert(stdError.arithmeticError);
-        optimismPortal2.depositERC20Transaction({
-            _to: address(0),
-            _mint: 1,
-            _value: 1,
-            _gasLimit: 10_000,
-            _isCreation: false,
-            _data: ""
-        });
-    }
-
-    /// @dev Tests that `balance()` returns the correct balance when the gas paying token is ether.
-    function testFuzz_balance_ether_succeeds(uint256 _amount) external {
-        // TODO(opcm upgrades): remove skip once upgrade path is implemented
-        skipIfForkTest("OptimismPortal2_Test: gas paying token functionality DNE on op mainnet");
-        // Check that the gas paying token is set to ether
-        (address token,) = systemConfig.gasPayingToken();
-        assertEq(token, Constants.ETHER);
-
-        // Increase the balance of the gas paying token
-        vm.deal(address(optimismPortal2), _amount);
-
-        // Check that the balance has been correctly updated
-        assertEq(optimismPortal2.balance(), address(optimismPortal2).balance);
-    }
-
     /// @dev Tests that the donateETH function donates ETH and does no state read/write
     function test_donateETH_succeeds(uint256 _amount) external {
         vm.startPrank(alice);
@@ -1005,152 +826,6 @@ contract OptimismPortal2_FinalizeWithdrawal_Test is CommonTest {
         assert(bob.balance == bobBalanceBefore + 100);
     }
 
-    /// @dev Tests that `finalizeWithdrawalTransaction` reverts when using a custom gas token.
-    /// @dev Should be removed when/if Custom Gas Token functionality is allowed again.
-    function test_finalizeWithdrawalTransaction_customGasToken_reverts() external {
-        Types.WithdrawalTransaction memory _defaultTx_noData = Types.WithdrawalTransaction({
-            nonce: 0,
-            sender: alice,
-            target: bob,
-            value: 100,
-            gasLimit: 100_000,
-            data: hex""
-        });
-        // Get withdrawal proof data we can use for testing.
-        (
-            bytes32 _stateRoot_noData,
-            bytes32 _storageRoot_noData,
-            bytes32 _outputRoot_noData,
-            bytes32 _withdrawalHash_noData,
-            bytes[] memory _withdrawalProof_noData
-        ) = ffi.getProveWithdrawalTransactionInputs(_defaultTx_noData);
-        // Setup a dummy output root proof for reuse.
-        Types.OutputRootProof memory _outputRootProof_noData = Types.OutputRootProof({
-            version: bytes32(uint256(0)),
-            stateRoot: _stateRoot_noData,
-            messagePasserStorageRoot: _storageRoot_noData,
-            latestBlockhash: bytes32(uint256(0))
-        });
-        uint256 _proposedBlockNumber_noData = 0xFF;
-        IFaultDisputeGame game_noData = IFaultDisputeGame(
-            payable(
-                address(
-                    disputeGameFactory.create(
-                        optimismPortal2.respectedGameType(),
-                        Claim.wrap(_outputRoot_noData),
-                        abi.encode(_proposedBlockNumber_noData)
-                    )
-                )
-            )
-        );
-        uint256 _proposedGameIndex_noData = disputeGameFactory.gameCount() - 1;
-        // Warp beyond the chess clocks and finalize the game.
-        vm.warp(block.timestamp + game_noData.maxClockDuration().raw() + 1 seconds);
-        // Fund the portal so that we can withdraw ETH.
-        vm.store(address(optimismPortal2), bytes32(uint256(61)), bytes32(uint256(0xFFFFFFFF)));
-        deal(address(L1Token), address(optimismPortal2), 0xFFFFFFFF);
-
-        // modify the gas token to be non ether
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(L1Token), 18)
-        );
-
-        vm.expectEmit(address(optimismPortal2));
-        emit WithdrawalProven(_withdrawalHash_noData, alice, bob);
-        vm.expectEmit(address(optimismPortal2));
-        emit WithdrawalProvenExtension1(_withdrawalHash_noData, address(this));
-        optimismPortal2.proveWithdrawalTransaction({
-            _tx: _defaultTx_noData,
-            _disputeGameIndex: _proposedGameIndex_noData,
-            _outputRootProof: _outputRootProof_noData,
-            _withdrawalProof: _withdrawalProof_noData
-        });
-
-        // Warp and resolve the dispute game.
-        game_noData.resolveClaim(0, 0);
-        game_noData.resolve();
-        vm.warp(block.timestamp + optimismPortal2.proofMaturityDelaySeconds() + 1 seconds);
-
-        vm.expectRevert(IOptimismPortal2.CustomGasTokenNotSupported.selector);
-        optimismPortal2.finalizeWithdrawalTransaction(_defaultTx_noData);
-    }
-
-    /// @dev Tests that `finalizeWithdrawalTransaction` succeeds when _tx.data is empty and with a custom gas token.
-    function test_finalizeWithdrawalTransaction_noTxDataNonEtherGasToken_succeeds() external {
-        vm.skip(true, "Custom gas token not supported");
-
-        Types.WithdrawalTransaction memory _defaultTx_noData = Types.WithdrawalTransaction({
-            nonce: 0,
-            sender: alice,
-            target: bob,
-            value: 100,
-            gasLimit: 100_000,
-            data: hex""
-        });
-        // Get withdrawal proof data we can use for testing.
-        (
-            bytes32 _stateRoot_noData,
-            bytes32 _storageRoot_noData,
-            bytes32 _outputRoot_noData,
-            bytes32 _withdrawalHash_noData,
-            bytes[] memory _withdrawalProof_noData
-        ) = ffi.getProveWithdrawalTransactionInputs(_defaultTx_noData);
-        // Setup a dummy output root proof for reuse.
-        Types.OutputRootProof memory _outputRootProof_noData = Types.OutputRootProof({
-            version: bytes32(uint256(0)),
-            stateRoot: _stateRoot_noData,
-            messagePasserStorageRoot: _storageRoot_noData,
-            latestBlockhash: bytes32(uint256(0))
-        });
-        uint256 _proposedBlockNumber_noData = 0xFF;
-        IFaultDisputeGame game_noData = IFaultDisputeGame(
-            payable(
-                address(
-                    disputeGameFactory.create(
-                        optimismPortal2.respectedGameType(),
-                        Claim.wrap(_outputRoot_noData),
-                        abi.encode(_proposedBlockNumber_noData)
-                    )
-                )
-            )
-        );
-        uint256 _proposedGameIndex_noData = disputeGameFactory.gameCount() - 1;
-        // Warp beyond the chess clocks and finalize the game.
-        vm.warp(block.timestamp + game_noData.maxClockDuration().raw() + 1 seconds);
-        // Fund the portal so that we can withdraw ETH.
-        vm.store(address(optimismPortal2), bytes32(uint256(61)), bytes32(uint256(0xFFFFFFFF)));
-        deal(address(L1Token), address(optimismPortal2), 0xFFFFFFFF);
-
-        // modify the gas token to be non ether
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(L1Token), 18)
-        );
-
-        uint256 bobBalanceBefore = L1Token.balanceOf(bob);
-
-        vm.expectEmit(address(optimismPortal2));
-        emit WithdrawalProven(_withdrawalHash_noData, alice, bob);
-        vm.expectEmit(address(optimismPortal2));
-        emit WithdrawalProvenExtension1(_withdrawalHash_noData, address(this));
-        optimismPortal2.proveWithdrawalTransaction({
-            _tx: _defaultTx_noData,
-            _disputeGameIndex: _proposedGameIndex_noData,
-            _outputRootProof: _outputRootProof_noData,
-            _withdrawalProof: _withdrawalProof_noData
-        });
-
-        // Warp and resolve the dispute game.
-        game_noData.resolveClaim(0, 0);
-        game_noData.resolve();
-        vm.warp(block.timestamp + optimismPortal2.proofMaturityDelaySeconds() + 1 seconds);
-
-        vm.expectEmit(true, true, false, true);
-        emit WithdrawalFinalized(_withdrawalHash_noData, true);
-        optimismPortal2.finalizeWithdrawalTransaction(_defaultTx_noData);
-
-        assert(L1Token.balanceOf(bob) == bobBalanceBefore + 100);
-    }
-
     /// @dev Tests that `finalizeWithdrawalTransaction` succeeds.
     function test_finalizeWithdrawalTransaction_provenWithdrawalHashEther_succeeds() external {
         uint256 bobBalanceBefore = address(bob).balance;
@@ -1239,32 +914,6 @@ contract OptimismPortal2_FinalizeWithdrawal_Test is CommonTest {
         assert(address(bob).balance == bobBalanceBefore + 100);
     }
 
-    /// @dev Tests that `finalizeWithdrawalTransaction` succeeds.
-    function test_finalizeWithdrawalTransaction_provenWithdrawalHashNonEtherTargetToken_reverts() external {
-        vm.skip(true, "Custom gas token not supported");
-
-        vm.mockCall(
-            address(systemConfig),
-            abi.encodeCall(systemConfig.gasPayingToken, ()),
-            abi.encode(address(_defaultTx.target), 18)
-        );
-
-        optimismPortal2.proveWithdrawalTransaction({
-            _tx: _defaultTx,
-            _disputeGameIndex: _proposedGameIndex,
-            _outputRootProof: _outputRootProof,
-            _withdrawalProof: _withdrawalProof
-        });
-
-        // Warp to after the finalization period
-        game.resolveClaim(0, 0);
-        game.resolve();
-        vm.warp(block.timestamp + optimismPortal2.proofMaturityDelaySeconds() + 1);
-
-        vm.expectRevert(BadTarget.selector);
-        optimismPortal2.finalizeWithdrawalTransaction(_defaultTx);
-    }
-
     /// @dev Tests that `finalizeWithdrawalTransaction` reverts if the contract is paused.
     function test_finalizeWithdrawalTransaction_paused_reverts() external {
         vm.prank(optimismPortal2.guardian());
@@ -1886,381 +1535,3 @@ contract OptimismPortal2_ResourceFuzz_Test is CommonTest {
         });
     }
 }
-
-contract OptimismPortal2WithMockERC20_Test is OptimismPortal2_FinalizeWithdrawal_Test {
-    MockERC20 token;
-
-    function setUp() public virtual override {
-        super.setUp();
-        token = new MockERC20("Test", "TST", 18);
-
-        // TODO(opcm upgrades): remove skip once upgrade path is implemented
-        skipIfForkTest("OptimismPortal2_Test: gas paying token functionality DNE on op mainnet");
-    }
-
-    function depositERC20Transaction(
-        address _from,
-        address _to,
-        uint256 _mint,
-        uint256 _value,
-        uint64 _gasLimit,
-        bool _isCreation,
-        bytes calldata _data
-    )
-        internal
-    {
-        if (_isCreation) {
-            _to = address(0);
-        }
-        if (_data.length > 120_000) {
-            _data = _data[0:120_000];
-        }
-        IResourceMetering.ResourceConfig memory rcfg = systemConfig.resourceConfig();
-        _gasLimit =
-            uint64(bound(_gasLimit, optimismPortal2.minimumGasLimit(uint64(_data.length)), rcfg.maxResourceLimit));
-
-        // Mint the token to the contract and approve the token for the portal
-        token.mint(address(this), _mint);
-        token.approve(address(optimismPortal2), _mint);
-
-        // Mock the gas paying token to be the ERC20 token
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(token), 18)
-        );
-
-        bytes memory opaqueData = abi.encodePacked(_mint, _value, _gasLimit, _isCreation, _data);
-
-        vm.expectEmit(address(optimismPortal2));
-        emit TransactionDeposited(
-            _from, // from
-            _to,
-            uint256(0), // DEPOSIT_VERSION
-            opaqueData
-        );
-
-        // Deposit the token into the portal
-        optimismPortal2.depositERC20Transaction(_to, _mint, _value, _gasLimit, _isCreation, _data);
-
-        // Assert final balance equals the deposited amount
-        assertEq(token.balanceOf(address(optimismPortal2)), _mint);
-        assertEq(optimismPortal2.balance(), _mint);
-    }
-
-    /// @dev Tests that `depositERC20Transaction` succeeds when msg.sender == tx.origin.
-    function testFuzz_depositERC20Transaction_senderIsOrigin_succeeds(
-        address _to,
-        uint256 _mint,
-        uint256 _value,
-        uint64 _gasLimit,
-        bool _isCreation,
-        bytes calldata _data
-    )
-        external
-    {
-        vm.skip(true, "Custom gas token not supported");
-
-        // Ensure that msg.sender == tx.origin
-        vm.startPrank(address(this), address(this));
-
-        depositERC20Transaction({
-            _from: address(this),
-            _to: _to,
-            _mint: _mint,
-            _value: _value,
-            _gasLimit: _gasLimit,
-            _isCreation: _isCreation,
-            _data: _data
-        });
-    }
-
-    /// @dev Tests that `depositERC20Transaction` succeeds when msg.sender != tx.origin.
-    function testFuzz_depositERC20Transaction_senderNotOrigin_succeeds(
-        address _to,
-        uint256 _mint,
-        uint256 _value,
-        uint64 _gasLimit,
-        bool _isCreation,
-        bytes calldata _data
-    )
-        external
-    {
-        vm.skip(true, "Custom gas token not supported");
-
-        // Ensure that msg.sender != tx.origin
-        vm.startPrank(address(this), address(1));
-
-        depositERC20Transaction({
-            _from: AddressAliasHelper.applyL1ToL2Alias(address(this)),
-            _to: _to,
-            _mint: _mint,
-            _value: _value,
-            _gasLimit: _gasLimit,
-            _isCreation: _isCreation,
-            _data: _data
-        });
-    }
-
-    /// @dev Tests that `depositERC20Transaction` reverts when not enough of the token is approved.
-    function test_depositERC20Transaction_notEnoughAmount_reverts() external {
-        vm.skip(true, "Custom gas token not supported");
-
-        // Mock the gas paying token to be the ERC20 token
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(token), 18)
-        );
-        vm.expectRevert(stdError.arithmeticError);
-        // Deposit the token into the portal
-        optimismPortal2.depositERC20Transaction(address(0), 1, 0, 0, false, "");
-    }
-
-    /// @dev Tests that `depositERC20Transaction` reverts when token balance does not update correctly after transfer.
-    function test_depositERC20Transaction_incorrectTokenBalance_reverts() external {
-        vm.skip(true, "Custom gas token not supported");
-
-        // Mint the token to the contract and approve the token for the portal
-        token.mint(address(this), 100);
-        token.approve(address(optimismPortal2), 100);
-
-        // Mock the gas paying token to be the ERC20 token
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(token), 18)
-        );
-
-        // Mock the token balance
-        vm.mockCall(address(token), abi.encodeCall(token.balanceOf, (address(optimismPortal2))), abi.encode(0));
-
-        // Call minimumGasLimit(0) before vm.expectRevert to ensure vm.expectRevert is for depositERC20Transaction
-        uint64 gasLimit = optimismPortal2.minimumGasLimit(0);
-
-        vm.expectRevert(TransferFailed.selector);
-
-        // Deposit the token into the portal
-        optimismPortal2.depositERC20Transaction(address(1), 100, 0, gasLimit, false, "");
-    }
-
-    /// @dev Tests that `depositERC20Transaction` reverts when creating a contract with a non-zero target.
-    function test_depositERC20Transaction_isCreationNotZeroTarget_reverts() external {
-        vm.skip(true, "Custom gas token not supported");
-
-        // Mock the gas paying token to be the ERC20 token
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(token), 18)
-        );
-
-        // Call minimumGasLimit(0) before vm.expectRevert to ensure vm.expectRevert is for depositERC20Transaction
-        uint64 gasLimit = optimismPortal2.minimumGasLimit(0);
-
-        vm.expectRevert(BadTarget.selector);
-        // Deposit the token into the portal
-        optimismPortal2.depositERC20Transaction(address(1), 0, 0, gasLimit, true, "");
-    }
-
-    /// @dev Tests that `depositERC20Transaction` reverts when the gas limit is too low.
-    function test_depositERC20Transaction_gasLimitTooLow_reverts() external {
-        vm.skip(true, "Custom gas token not supported");
-
-        // Mock the gas paying token to be the ERC20 token
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(token), 18)
-        );
-
-        vm.expectRevert(SmallGasLimit.selector);
-        // Deposit the token into the portal
-        optimismPortal2.depositERC20Transaction(address(0), 0, 0, 0, false, "");
-    }
-
-    /// @dev Tests that `depositERC20Transaction` reverts when the data is too large.
-    function test_depositERC20Transaction_dataTooLarge_reverts() external {
-        vm.skip(true, "Custom gas token not supported");
-
-        bytes memory data = new bytes(120_001);
-        data[120_000] = 0x01;
-
-        // Mock the gas paying token to be the ERC20 token
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(token), 18)
-        );
-
-        uint64 gasLimit = optimismPortal2.minimumGasLimit(120_001);
-        vm.expectRevert(LargeCalldata.selector);
-        // Deposit the token into the portal
-        optimismPortal2.depositERC20Transaction(address(0), 0, 0, gasLimit, false, data);
-    }
-
-    /// @dev Tests that `balance()` returns the correct balance when the gas paying token is not ether.
-    function testFuzz_balance_nonEther_succeeds(uint256 _amount) external {
-        vm.skip(true, "Custom gas token not supported");
-
-        // Mint the token to the contract and approve the token for the portal
-        token.mint(address(this), _amount);
-        token.approve(address(optimismPortal2), _amount);
-
-        // Mock the gas paying token to be the ERC20 token
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(token), 18)
-        );
-
-        // Deposit the token into the portal
-        optimismPortal2.depositERC20Transaction(address(0), _amount, 0, optimismPortal2.minimumGasLimit(0), false, "");
-
-        // Check that the balance has been correctly updated
-        assertEq(optimismPortal2.balance(), _amount);
-    }
-
-    /// @dev Tests that `finalizeWithdrawalTransaction` succeeds.
-    function test_finalizeWithdrawalTransaction_provenWithdrawalHashWithNonEther_succeeds() external {
-        vm.skip(true, "Custom gas token not supported");
-
-        // Mint the token to the contract and approve the token for the portal
-        token.mint(address(this), _defaultTx.value);
-        token.approve(address(optimismPortal2), _defaultTx.value);
-
-        // Mock the gas paying token to be the ERC20 token
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(token), 18)
-        );
-
-        // Deposit the token into the portal
-        optimismPortal2.depositERC20Transaction(
-            address(bob), _defaultTx.value, 0, optimismPortal2.minimumGasLimit(0), false, ""
-        );
-
-        assertEq(optimismPortal2.balance(), _defaultTx.value);
-
-        vm.expectEmit(address(optimismPortal2));
-        emit WithdrawalProven(_withdrawalHash, alice, bob);
-        optimismPortal2.proveWithdrawalTransaction({
-            _tx: _defaultTx,
-            _disputeGameIndex: _proposedGameIndex,
-            _outputRootProof: _outputRootProof,
-            _withdrawalProof: _withdrawalProof
-        });
-
-        // Warp past the finalization period.
-        game.resolveClaim(0, 0);
-        game.resolve();
-        vm.warp(block.timestamp + optimismPortal2.proofMaturityDelaySeconds() + 1);
-
-        vm.expectEmit(address(optimismPortal2));
-        emit WithdrawalFinalized(_withdrawalHash, true);
-
-        vm.expectCall(_defaultTx.target, 0, _defaultTx.data);
-
-        vm.expectCall(address(token), 0, abi.encodeCall(token.transfer, (_defaultTx.target, _defaultTx.value)));
-
-        optimismPortal2.finalizeWithdrawalTransaction(_defaultTx);
-
-        assertEq(optimismPortal2.balance(), 0);
-        assertEq(token.balanceOf(address(bob)), 100);
-    }
-
-    /// @dev Helper for depositing a transaction.
-    function depositTransaction(
-        address _from,
-        address _to,
-        uint256 _value,
-        uint64 _gasLimit,
-        bool _isCreation,
-        bytes calldata _data
-    )
-        internal
-    {
-        if (_isCreation) {
-            _to = address(0);
-        }
-        if (_data.length > 120_000) {
-            _data = _data[0:120_000];
-        }
-
-        IResourceMetering.ResourceConfig memory rcfg = systemConfig.resourceConfig();
-        _gasLimit =
-            uint64(bound(_gasLimit, optimismPortal2.minimumGasLimit(uint64(_data.length)), rcfg.maxResourceLimit));
-
-        // Mock the gas paying token to be the ERC20 token
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(token), 18)
-        );
-
-        bytes memory opaqueData = abi.encodePacked(uint256(0), _value, _gasLimit, _isCreation, _data);
-
-        vm.expectEmit(address(optimismPortal2));
-        emit TransactionDeposited(
-            _from, // from
-            _to,
-            uint256(0), // DEPOSIT_VERSION
-            opaqueData
-        );
-
-        // Deposit the token into the portal
-        optimismPortal2.depositTransaction(_to, _value, _gasLimit, _isCreation, _data);
-
-        // Assert final balance equals the deposited amount
-        assertEq(token.balanceOf(address(optimismPortal2)), 0);
-        assertEq(optimismPortal2.balance(), 0);
-    }
-
-    /// @dev Tests that `depositTransaction` succeeds when a custom gas token is used but the msg.value is zero.
-    function testFuzz_depositTransaction_customGasTokenWithNoValueAndSenderIsOrigin_succeeds(
-        address _to,
-        uint256 _value,
-        uint64 _gasLimit,
-        bool _isCreation,
-        bytes calldata _data
-    )
-        external
-    {
-        vm.skip(true, "Custom gas token not supported");
-
-        // Ensure that msg.sender == tx.origin
-        vm.startPrank(address(this), address(this));
-
-        depositTransaction({
-            _from: address(this),
-            _to: _to,
-            _value: _value,
-            _gasLimit: _gasLimit,
-            _isCreation: _isCreation,
-            _data: _data
-        });
-    }
-
-    /// @dev Tests that `depositTransaction` succeeds when a custom gas token is used but the msg.value is zero.
-    function testFuzz_depositTransaction_customGasTokenWithNoValueAndSenderNotOrigin_succeeds(
-        address _to,
-        uint256 _value,
-        uint64 _gasLimit,
-        bool _isCreation,
-        bytes calldata _data
-    )
-        external
-    {
-        vm.skip(true, "Custom gas token not supported");
-
-        // Ensure that msg.sender != tx.origin
-        vm.startPrank(address(this), address(1));
-
-        depositTransaction({
-            _from: AddressAliasHelper.applyL1ToL2Alias(address(this)),
-            _to: _to,
-            _value: _value,
-            _gasLimit: _gasLimit,
-            _isCreation: _isCreation,
-            _data: _data
-        });
-    }
-
-    /// @dev Tests that `depositTransaction` fails when a custom gas token is used and msg.value is non-zero.
-    function test_depositTransaction_customGasTokenWithValue_reverts() external {
-        vm.skip(true, "Custom gas token not supported");
-
-        // Mock the gas paying token to be the ERC20 token
-        vm.mockCall(
-            address(systemConfig), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(token), 18)
-        );
-
-        vm.expectRevert(NoValue.selector);
-
-        // Deposit the token into the portal
-        optimismPortal2.depositTransaction{ value: 100 }(address(0), 0, 0, false, "");
-    }
-}

packages/contracts-bedrock/test/L1/OptimismPortalInterop.t.sol

@@ -21,20 +21,16 @@ contract OptimismPortalInterop_Test is CommonTest {
         super.setUp();
     }
 
-    /// @dev Tests that the config for the gas paying token can be set.
-    function testFuzz_setConfig_gasPayingToken_succeeds(bytes calldata _value) public {
-        vm.expectEmit(address(optimismPortal2));
-        emitTransactionDeposited({
-            _from: Constants.DEPOSITOR_ACCOUNT,
-            _to: Predeploys.L1_BLOCK_ATTRIBUTES,
-            _value: 0,
-            _mint: 0,
-            _gasLimit: 200_000,
-            _isCreation: false,
-            _data: abi.encodeCall(IL1BlockInterop.setConfig, (ConfigType.SET_GAS_PAYING_TOKEN, _value))
-        });
+    /// @notice Tests that the version function returns a valid string. We avoid testing the
+    ///         specific value of the string as it changes frequently.
+    function test_version_succeeds() external view {
+        assert(bytes(_optimismPortalInterop().version()).length > 0);
+    }
 
+    /// @dev Tests that the config for the gas paying token cannot be set.
+    function testFuzz_setConfig_gasPayingToken_reverts(bytes calldata _value) public {
         vm.prank(address(_optimismPortalInterop().systemConfig()));
+        vm.expectRevert(IOptimismPortalInterop.CustomGasTokenNotSupported.selector);
         _optimismPortalInterop().setConfig(ConfigType.SET_GAS_PAYING_TOKEN, _value);
     }
 

packages/contracts-bedrock/test/L1/SystemConfig.t.sol

@@ -4,19 +4,13 @@ pragma solidity 0.8.15;
 // Testing
 import { CommonTest } from "test/setup/CommonTest.sol";
 
-// Contracts
-import { ERC20 } from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
-
 // Libraries
 import { Constants } from "src/libraries/Constants.sol";
-import { Predeploys } from "src/libraries/Predeploys.sol";
-import { GasPayingToken } from "src/libraries/GasPayingToken.sol";
 import { EIP1967Helper } from "test/mocks/EIP1967Helper.sol";
 
 // Interfaces
 import { IResourceMetering } from "interfaces/L1/IResourceMetering.sol";
 import { ISystemConfig } from "interfaces/L1/ISystemConfig.sol";
-import { IL1Block } from "interfaces/L2/IL1Block.sol";
 
 contract SystemConfig_Init is CommonTest {
     event ConfigUpdate(uint256 indexed version, ISystemConfig.UpdateType indexed updateType, bytes data);
@@ -47,6 +41,12 @@ contract SystemConfig_Initialize_Test is SystemConfig_Init {
         optimismMintableERC20Factory = artifacts.mustGetAddress("OptimismMintableERC20FactoryProxy");
     }
 
+    /// @notice Tests that the version function returns a valid string. We avoid testing the
+    ///         specific value of the string as it changes frequently.
+    function test_version_succeeds() external view {
+        assert(bytes(systemConfig.version()).length > 0);
+    }
+
     /// @dev Tests that constructor sets the correct values.
     function test_constructor_succeeds() external view {
         ISystemConfig impl = ISystemConfig(systemConfigImpl);
@@ -74,10 +74,6 @@ contract SystemConfig_Initialize_Test is SystemConfig_Init {
         assertEq(address(impl.disputeGameFactory()), address(0));
         assertEq(address(impl.optimismPortal()), address(0));
         assertEq(address(impl.optimismMintableERC20Factory()), address(0));
-        // Check gas paying token
-        (address token, uint8 decimals) = impl.gasPayingToken();
-        assertEq(token, Constants.ETHER);
-        assertEq(decimals, 18);
     }
 
     /// @dev Tests that initialization sets the correct values.
@@ -110,10 +106,6 @@ contract SystemConfig_Initialize_Test is SystemConfig_Init {
         assertEq(address(systemConfig.disputeGameFactory()), address(disputeGameFactory));
         assertEq(address(systemConfig.optimismPortal()), address(optimismPortal2));
         assertEq(address(systemConfig.optimismMintableERC20Factory()), address(optimismMintableERC20Factory));
-        // Check gas paying token
-        (address token, uint8 decimals) = systemConfig.gasPayingToken();
-        assertEq(token, Constants.ETHER);
-        assertEq(decimals, 18);
     }
 }
 
@@ -144,8 +136,7 @@ contract SystemConfig_Initialize_TestFail is SystemConfig_Initialize_Test {
                 l1StandardBridge: address(0),
                 disputeGameFactory: address(0),
                 optimismPortal: address(0),
-                optimismMintableERC20Factory: address(0),
-                gasPayingToken: Constants.ETHER
+                optimismMintableERC20Factory: address(0)
             })
         });
     }
@@ -174,8 +165,7 @@ contract SystemConfig_Initialize_TestFail is SystemConfig_Initialize_Test {
                 l1StandardBridge: address(0),
                 disputeGameFactory: address(0),
                 optimismPortal: address(0),
-                optimismMintableERC20Factory: address(0),
-                gasPayingToken: Constants.ETHER
+                optimismMintableERC20Factory: address(0)
             })
         });
         assertEq(systemConfig.startBlock(), block.number);
@@ -205,8 +195,7 @@ contract SystemConfig_Initialize_TestFail is SystemConfig_Initialize_Test {
                 l1StandardBridge: address(0),
                 disputeGameFactory: address(0),
                 optimismPortal: address(0),
-                optimismMintableERC20Factory: address(0),
-                gasPayingToken: Constants.ETHER
+                optimismMintableERC20Factory: address(0)
             })
         });
         assertEq(systemConfig.startBlock(), 1);
@@ -315,191 +304,10 @@ contract SystemConfig_Init_ResourceConfig is SystemConfig_Init {
                 l1StandardBridge: address(0),
                 disputeGameFactory: address(0),
                 optimismPortal: address(0),
-                optimismMintableERC20Factory: address(0),
-                gasPayingToken: address(0)
-            })
-        });
-    }
-}
-
-contract SystemConfig_Init_CustomGasToken is SystemConfig_Init {
-    ERC20 token;
-
-    function setUp() public override {
-        vm.skip(true, "Custom gas token not supported");
-
-        token = new ERC20("Silly", "SIL");
-        super.enableCustomGasToken(address(token));
-
-        super.setUp();
-    }
-
-    /// @dev Helper to clean storage and then initialize the system config with an arbitrary gas token address.
-    function cleanStorageAndInit(address _gasPayingToken) internal {
-        vm.store(address(systemConfig), bytes32(0), bytes32(0)); // initailizer
-        vm.store(address(systemConfig), GasPayingToken.GAS_PAYING_TOKEN_SLOT, bytes32(0));
-        vm.store(address(systemConfig), GasPayingToken.GAS_PAYING_TOKEN_NAME_SLOT, bytes32(0));
-        vm.store(address(systemConfig), GasPayingToken.GAS_PAYING_TOKEN_SYMBOL_SLOT, bytes32(0));
-
-        systemConfig.initialize({
-            _owner: alice,
-            _basefeeScalar: 2100,
-            _blobbasefeeScalar: 1000000,
-            _batcherHash: bytes32(hex"abcd"),
-            _gasLimit: 30_000_000,
-            _unsafeBlockSigner: address(1),
-            _config: Constants.DEFAULT_RESOURCE_CONFIG(),
-            _batchInbox: address(0),
-            _addresses: ISystemConfig.Addresses({
-                l1CrossDomainMessenger: address(0),
-                l1ERC721Bridge: address(0),
-                disputeGameFactory: address(0),
-                l1StandardBridge: address(0),
-                optimismPortal: address(optimismPortal2),
-                optimismMintableERC20Factory: address(0),
-                gasPayingToken: _gasPayingToken
+                optimismMintableERC20Factory: address(0)
             })
         });
     }
-
-    /// @dev Tests that initialization sets the correct values and getters work.
-    function test_initialize_customGasToken_succeeds() external view {
-        (address addr, uint8 decimals) = systemConfig.gasPayingToken();
-        assertEq(addr, address(token));
-        assertEq(decimals, 18);
-
-        assertEq(systemConfig.gasPayingTokenName(), token.name());
-        assertEq(systemConfig.gasPayingTokenSymbol(), token.symbol());
-    }
-
-    /// @dev Tests that initialization sets the correct values and getters work.
-    function testFuzz_initialize_customGasToken_succeeds(
-        address _token,
-        string calldata _name,
-        string calldata _symbol
-    )
-        external
-    {
-        // don't use vm's address
-        vm.assume(_token != address(vm));
-        // don't use console's address
-        vm.assume(_token != CONSOLE);
-        // don't use create2 deployer's address
-        vm.assume(_token != CREATE2_FACTORY);
-        // don't use default test's address
-        vm.assume(_token != DEFAULT_TEST_CONTRACT);
-        // don't use multicall3's address
-        vm.assume(_token != MULTICALL3_ADDRESS);
-
-        // Using vm.assume() would cause too many test rejections.
-        string memory name = _name;
-        if (bytes(_name).length > 32) {
-            name = _name[:32];
-        }
-
-        // Using vm.assume() would cause too many test rejections.
-        string memory symbol = _symbol;
-        if (bytes(_symbol).length > 32) {
-            symbol = _symbol[:32];
-        }
-
-        vm.mockCall(_token, abi.encodeCall(token.decimals, ()), abi.encode(18));
-        vm.mockCall(_token, abi.encodeCall(token.name, ()), abi.encode(name));
-        vm.mockCall(_token, abi.encodeCall(token.symbol, ()), abi.encode(symbol));
-
-        cleanStorageAndInit(_token);
-
-        (address addr, uint8 decimals) = systemConfig.gasPayingToken();
-        assertEq(decimals, 18);
-
-        if (_token == address(0) || _token == Constants.ETHER) {
-            assertEq(addr, Constants.ETHER);
-            assertEq(systemConfig.gasPayingTokenName(), "Ether");
-            assertEq(systemConfig.gasPayingTokenSymbol(), "ETH");
-        } else {
-            assertEq(addr, _token);
-            assertEq(systemConfig.gasPayingTokenName(), name);
-            assertEq(systemConfig.gasPayingTokenSymbol(), symbol);
-        }
-    }
-
-    /// @dev Tests that initialization sets the correct values and getters work when token address passed is 0.
-    function test_initialize_customGasTokenWithZeroTokenAddress_succeeds() external {
-        cleanStorageAndInit(address(0));
-
-        (address addr, uint8 decimals) = systemConfig.gasPayingToken();
-        assertEq(addr, address(Constants.ETHER));
-        assertEq(decimals, 18);
-
-        assertEq(systemConfig.gasPayingTokenName(), "Ether");
-        assertEq(systemConfig.gasPayingTokenSymbol(), "ETH");
-    }
-
-    /// @dev Tests that initialization sets the correct values and getters work when token address is Constants.ETHER
-    function test_initialize_customGasTokenWithEtherTokenAddress_succeeds() external {
-        cleanStorageAndInit(Constants.ETHER);
-
-        (address addr, uint8 decimals) = systemConfig.gasPayingToken();
-        assertEq(addr, address(Constants.ETHER));
-        assertEq(decimals, 18);
-
-        assertEq(systemConfig.gasPayingTokenName(), "Ether");
-        assertEq(systemConfig.gasPayingTokenSymbol(), "ETH");
-    }
-
-    /// @dev Tests that initialization fails if decimals are not 18.
-    function test_initialize_customGasTokenWrongDecimals_fails() external {
-        vm.mockCall(address(token), abi.encodeCall(token.decimals, ()), abi.encode(8));
-        vm.expectRevert("SystemConfig: bad decimals of gas paying token");
-
-        cleanStorageAndInit(address(token));
-    }
-
-    /// @dev Tests that initialization fails if name is too long.
-    function test_initialize_customGasTokenNameTooLong_fails() external {
-        string memory name = new string(32);
-        name = string.concat(name, "a");
-
-        vm.mockCall(address(token), abi.encodeCall(token.name, ()), abi.encode(name));
-        vm.expectRevert("GasPayingToken: string cannot be greater than 32 bytes");
-
-        cleanStorageAndInit(address(token));
-    }
-
-    /// @dev Tests that initialization fails if symbol is too long.
-    function test_initialize_customGasTokenSymbolTooLong_fails() external {
-        string memory symbol = new string(33);
-        symbol = string.concat(symbol, "a");
-
-        vm.mockCall(address(token), abi.encodeCall(token.symbol, ()), abi.encode(symbol));
-        vm.expectRevert("GasPayingToken: string cannot be greater than 32 bytes");
-
-        cleanStorageAndInit(address(token));
-    }
-
-    /// @dev Tests that initialization works with OptimismPortal.
-    function test_initialize_customGasTokenCall_succeeds() external {
-        vm.expectCall(
-            address(optimismPortal2),
-            abi.encodeCall(optimismPortal2.setGasPayingToken, (address(token), 18, bytes32("Silly"), bytes32("SIL")))
-        );
-
-        vm.expectEmit(address(optimismPortal2));
-        emit TransactionDeposited(
-            0xDeaDDEaDDeAdDeAdDEAdDEaddeAddEAdDEAd0001,
-            Predeploys.L1_BLOCK_ATTRIBUTES,
-            0, // deposit version
-            abi.encodePacked(
-                uint256(0), // mint
-                uint256(0), // value
-                uint64(200_000), // gasLimit
-                false, // isCreation,
-                abi.encodeCall(IL1Block.setGasPayingToken, (address(token), 18, bytes32("Silly"), bytes32("SIL")))
-            )
-        );
-
-        cleanStorageAndInit(address(token));
-    }
 }
 
 contract SystemConfig_Setters_TestFail is SystemConfig_Init {

packages/contracts-bedrock/test/L1/SystemConfigInterop.t.sol

@@ -4,16 +4,10 @@ pragma solidity 0.8.15;
 // Testing
 import { CommonTest } from "test/setup/CommonTest.sol";
 
-// Contracts
-import { ERC20 } from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
-
 // Libraries
-import { Constants } from "src/libraries/Constants.sol";
 import { StaticConfig } from "src/libraries/StaticConfig.sol";
-import { GasPayingToken } from "src/libraries/GasPayingToken.sol";
 
 // Interfaces
-import { ISystemConfig } from "interfaces/L1/ISystemConfig.sol";
 import { ISystemConfigInterop } from "interfaces/L1/ISystemConfigInterop.sol";
 import { IOptimismPortalInterop } from "interfaces/L1/IOptimismPortalInterop.sol";
 import { ConfigType } from "interfaces/L2/IL1BlockInterop.sol";
@@ -26,110 +20,10 @@ contract SystemConfigInterop_Test is CommonTest {
         super.setUp();
     }
 
-    /// @dev Temporary test that checks that correct calls to initialize when using a custom gas token revert with the
-    /// expected error.
-    /// @dev Should be removed when/if Custom Gas Token functionality is allowed again.
-    function test_initialize_customGasToken_reverts() external {
-        vm.expectRevert(ISystemConfig.CustomGasTokenNotSupported.selector);
-        _cleanStorageAndInit(address(L1Token));
-    }
-
-    /// @dev Tests that when the decimals is not 18, initialization reverts.
-    function test_initialize_decimalsIsNot18_reverts(uint8 decimals) external {
-        vm.skip(true, "Custom gas token not supported");
-
-        vm.assume(decimals != 18);
-        address _token = address(L1Token);
-
-        vm.mockCall(_token, abi.encodeCall(ERC20.name, ()), abi.encode("Token"));
-        vm.mockCall(_token, abi.encodeCall(ERC20.symbol, ()), abi.encode("TKN"));
-        vm.mockCall(_token, abi.encodeCall(ERC20.decimals, ()), abi.encode(decimals));
-
-        vm.expectRevert("SystemConfig: bad decimals of gas paying token");
-        _cleanStorageAndInit(_token);
-    }
-
-    /// @dev Temporary test that checks that correct calls to setGasPayingToken when using a custom gas token revert
-    /// with the expected error.
-    /// @dev Should be removed when/if Custom Gas Token functionality is allowed again.
-    function test_setGasPayingToken_customGasToken_reverts(
-        address _token,
-        string calldata _name,
-        string calldata _symbol
-    )
-        external
-    {
-        assumeNotForgeAddress(_token);
-        vm.assume(_token != address(0));
-        vm.assume(_token != Constants.ETHER);
-
-        // Using vm.assume() would cause too many test rejections.
-        string memory name = _name;
-        if (bytes(_name).length > 32) {
-            name = _name[:32];
-        }
-
-        // Using vm.assume() would cause too many test rejections.
-        string memory symbol = _symbol;
-        if (bytes(_symbol).length > 32) {
-            symbol = _symbol[:32];
-        }
-
-        vm.mockCall(_token, abi.encodeCall(ERC20.decimals, ()), abi.encode(18));
-        vm.mockCall(_token, abi.encodeCall(ERC20.name, ()), abi.encode(name));
-        vm.mockCall(_token, abi.encodeCall(ERC20.symbol, ()), abi.encode(symbol));
-
-        vm.expectRevert(ISystemConfig.CustomGasTokenNotSupported.selector);
-        _cleanStorageAndInit(_token);
-    }
-
-    /// @dev Tests that the gas paying token can be set.
-    function testFuzz_setGasPayingToken_succeeds(
-        address _token,
-        string calldata _name,
-        string calldata _symbol
-    )
-        public
-    {
-        vm.skip(true, "Custom gas token not supported");
-
-        assumeNotForgeAddress(_token);
-        vm.assume(_token != address(0));
-        vm.assume(_token != Constants.ETHER);
-
-        // Using vm.assume() would cause too many test rejections.
-        string memory name = _name;
-        if (bytes(_name).length > 32) {
-            name = _name[:32];
-        }
-
-        // Using vm.assume() would cause too many test rejections.
-        string memory symbol = _symbol;
-        if (bytes(_symbol).length > 32) {
-            symbol = _symbol[:32];
-        }
-
-        vm.mockCall(_token, abi.encodeCall(ERC20.decimals, ()), abi.encode(18));
-        vm.mockCall(_token, abi.encodeCall(ERC20.name, ()), abi.encode(name));
-        vm.mockCall(_token, abi.encodeCall(ERC20.symbol, ()), abi.encode(symbol));
-
-        vm.expectCall(
-            address(optimismPortal2),
-            abi.encodeCall(
-                IOptimismPortalInterop.setConfig,
-                (
-                    ConfigType.SET_GAS_PAYING_TOKEN,
-                    StaticConfig.encodeSetGasPayingToken({
-                        _token: _token,
-                        _decimals: 18,
-                        _name: GasPayingToken.sanitize(name),
-                        _symbol: GasPayingToken.sanitize(symbol)
-                    })
-                )
-            )
-        );
-
-        _cleanStorageAndInit(_token);
+    /// @notice Tests that the version function returns a valid string. We avoid testing the
+    ///         specific value of the string as it changes frequently.
+    function test_version_succeeds() external view {
+        assert(bytes(_systemConfigInterop().version()).length > 0);
     }
 
     /// @dev Tests that a dependency can be added.
@@ -176,35 +70,6 @@ contract SystemConfigInterop_Test is CommonTest {
         _systemConfigInterop().removeDependency(_chainId);
     }
 
-    /// @dev Helper to clean storage and then initialize the system config with an arbitrary gas token address.
-    function _cleanStorageAndInit(address _token) internal {
-        // Wipe out the initialized slot so the proxy can be initialized again
-        vm.store(address(systemConfig), bytes32(0), bytes32(0));
-        vm.store(address(systemConfig), GasPayingToken.GAS_PAYING_TOKEN_SLOT, bytes32(0));
-        vm.store(address(systemConfig), GasPayingToken.GAS_PAYING_TOKEN_NAME_SLOT, bytes32(0));
-        vm.store(address(systemConfig), GasPayingToken.GAS_PAYING_TOKEN_SYMBOL_SLOT, bytes32(0));
-
-        systemConfig.initialize({
-            _owner: alice,
-            _basefeeScalar: 2100,
-            _blobbasefeeScalar: 1000000,
-            _batcherHash: bytes32(hex"abcd"),
-            _gasLimit: 30_000_000,
-            _unsafeBlockSigner: address(1),
-            _config: Constants.DEFAULT_RESOURCE_CONFIG(),
-            _batchInbox: address(0),
-            _addresses: ISystemConfig.Addresses({
-                l1CrossDomainMessenger: address(0),
-                l1ERC721Bridge: address(0),
-                disputeGameFactory: address(0),
-                l1StandardBridge: address(0),
-                optimismPortal: address(optimismPortal2),
-                optimismMintableERC20Factory: address(0),
-                gasPayingToken: _token
-            })
-        });
-    }
-
     /// @dev Returns the SystemConfigInterop instance.
     function _systemConfigInterop() internal view returns (ISystemConfigInterop) {
         return ISystemConfigInterop(address(systemConfig));

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

@@ -16,6 +16,7 @@ import { AddressAliasHelper } from "src/vendor/AddressAliasHelper.sol";
 // Interfaces
 import { IL2CrossDomainMessenger } from "interfaces/L2/IL2CrossDomainMessenger.sol";
 import { IL2ToL1MessagePasser } from "interfaces/L2/IL2ToL1MessagePasser.sol";
+import { IGasToken } from "src/libraries/GasPayingToken.sol";
 
 contract L2CrossDomainMessenger_Test is CommonTest {
     /// @dev Receiver address for testing
@@ -315,7 +316,7 @@ contract L2CrossDomainMessenger_Test is CommonTest {
     /// @dev Tests that sendMessage succeeds with a custom gas token when the call value is zero.
     function test_sendMessage_customGasTokenButNoValue_succeeds() external {
         // Mock the gasPayingToken function to return a custom gas token
-        vm.mockCall(address(l1Block), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(2)));
+        vm.mockCall(address(l1Block), abi.encodeCall(IGasToken.gasPayingToken, ()), abi.encode(address(1), uint8(2)));
 
         bytes memory xDomainCallData =
             Encoding.encodeCrossDomainMessage(l2CrossDomainMessenger.messageNonce(), alice, recipient, 0, 100, hex"ff");
@@ -355,7 +356,7 @@ contract L2CrossDomainMessenger_Test is CommonTest {
     /// @dev Tests that the sendMessage reverts when call value is non-zero with custom gas token.
     function test_sendMessage_customGasTokenWithValue_reverts() external {
         // Mock the gasPayingToken function to return a custom gas token
-        vm.mockCall(address(l1Block), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(2)));
+        vm.mockCall(address(l1Block), abi.encodeCall(IGasToken.gasPayingToken, ()), abi.encode(address(1), uint8(2)));
 
         vm.expectRevert("CrossDomainMessenger: cannot send value with custom gas token");
         l2CrossDomainMessenger.sendMessage{ value: 1 }(recipient, hex"ff", uint32(100));
@@ -364,7 +365,7 @@ contract L2CrossDomainMessenger_Test is CommonTest {
     /// @dev Tests that the relayMessage succeeds with a custom gas token when the call value is zero.
     function test_relayMessage_customGasTokenAndNoValue_succeeds() external {
         // Mock the gasPayingToken function to return a custom gas token
-        vm.mockCall(address(l1Block), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(2)));
+        vm.mockCall(address(l1Block), abi.encodeCall(IGasToken.gasPayingToken, ()), abi.encode(address(1), uint8(2)));
 
         address target = address(0xabcd);
         address sender = address(l1CrossDomainMessenger);
@@ -400,7 +401,7 @@ contract L2CrossDomainMessenger_Test is CommonTest {
     ///       The L1CrossDomainMessenger `sendMessage` function cannot send value with a custom gas token.
     function test_relayMessage_customGasTokenWithValue_reverts() external virtual {
         // Mock the gasPayingToken function to return a custom gas token
-        vm.mockCall(address(l1Block), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(2)));
+        vm.mockCall(address(l1Block), abi.encodeCall(IGasToken.gasPayingToken, ()), abi.encode(address(1), uint8(2)));
         vm.expectRevert("CrossDomainMessenger: value must be zero unless message is from a system address");
 
         l2CrossDomainMessenger.relayMessage{ value: 1 }(

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

@@ -20,6 +20,7 @@ import { ICrossDomainMessenger } from "interfaces/universal/ICrossDomainMessenge
 import { IStandardBridge } from "interfaces/universal/IStandardBridge.sol";
 import { IL2ToL1MessagePasser } from "interfaces/L2/IL2ToL1MessagePasser.sol";
 import { IL2StandardBridge } from "interfaces/L2/IL2StandardBridge.sol";
+import { IGasToken } from "src/libraries/GasPayingToken.sol";
 
 contract L2StandardBridge_Test is CommonTest {
     using stdStorage for StdStorage;
@@ -130,7 +131,7 @@ contract L2StandardBridge_Test is CommonTest {
     /// @dev Tests that the receive function reverts with custom gas token.
     function testFuzz_receive_customGasToken_reverts(uint256 _value) external {
         vm.prank(alice, alice);
-        vm.mockCall(address(l1Block), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(2)));
+        vm.mockCall(address(l1Block), abi.encodeCall(IGasToken.gasPayingToken, ()), abi.encode(address(1), uint8(2)));
         vm.deal(alice, _value);
         (bool success, bytes memory data) = address(l2StandardBridge).call{ value: _value }(hex"");
         assertFalse(success);
@@ -169,9 +170,7 @@ contract L2StandardBridge_Test is CommonTest {
 
     /// @dev Tests that `withdraw` reverts with custom gas token.
     function test_withdraw_customGasToken_reverts() external {
-        vm.mockCall(
-            address(l1Block), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(18))
-        );
+        vm.mockCall(address(l1Block), abi.encodeCall(IGasToken.gasPayingToken, ()), abi.encode(address(1), uint8(18)));
         vm.expectRevert("L2StandardBridge: not supported with custom gas token");
         vm.prank(alice, alice);
         l2StandardBridge.withdraw(address(Predeploys.LEGACY_ERC20_ETH), 1, 1, hex"");
@@ -179,9 +178,7 @@ contract L2StandardBridge_Test is CommonTest {
 
     /// @dev Tests that `withdraw` reverts with custom gas token.
     function test_withdrawERC20_customGasToken_reverts() external {
-        vm.mockCall(
-            address(l1Block), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(18))
-        );
+        vm.mockCall(address(l1Block), abi.encodeCall(IGasToken.gasPayingToken, ()), abi.encode(address(1), uint8(18)));
         vm.expectRevert("L2StandardBridge: not supported with custom gas token");
         vm.prank(alice, alice);
         l2StandardBridge.withdraw(address(L1Token), 1, 1, hex"");
@@ -190,9 +187,7 @@ contract L2StandardBridge_Test is CommonTest {
     /// @dev Tests that `withdraw` reverts with custom gas token.
     function test_withdrawERC20WithValue_customGasToken_reverts() external {
         vm.deal(alice, 1 ether);
-        vm.mockCall(
-            address(l1Block), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(18))
-        );
+        vm.mockCall(address(l1Block), abi.encodeCall(IGasToken.gasPayingToken, ()), abi.encode(address(1), uint8(18)));
         vm.expectRevert("L2StandardBridge: not supported with custom gas token");
         vm.prank(alice, alice);
         l2StandardBridge.withdraw{ value: 1 ether }(address(L1Token), 1, 1, hex"");
@@ -201,9 +196,7 @@ contract L2StandardBridge_Test is CommonTest {
     /// @dev Tests that `withdraw` with value reverts with custom gas token.
     function test_withdraw_customGasTokenWithValue_reverts() external {
         vm.deal(alice, 1 ether);
-        vm.mockCall(
-            address(l1Block), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(18))
-        );
+        vm.mockCall(address(l1Block), abi.encodeCall(IGasToken.gasPayingToken, ()), abi.encode(address(1), uint8(18)));
         vm.expectRevert("L2StandardBridge: not supported with custom gas token");
         vm.prank(alice, alice);
         l2StandardBridge.withdraw{ value: 1 ether }(address(Predeploys.LEGACY_ERC20_ETH), 1, 1, hex"");
@@ -211,9 +204,7 @@ contract L2StandardBridge_Test is CommonTest {
 
     /// @dev Tests that `withdrawTo` reverts with custom gas token.
     function test_withdrawTo_customGasToken_reverts() external {
-        vm.mockCall(
-            address(l1Block), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(18))
-        );
+        vm.mockCall(address(l1Block), abi.encodeCall(IGasToken.gasPayingToken, ()), abi.encode(address(1), uint8(18)));
         vm.expectRevert("L2StandardBridge: not supported with custom gas token");
         vm.prank(alice, alice);
         l2StandardBridge.withdrawTo(address(Predeploys.LEGACY_ERC20_ETH), bob, 1, 1, hex"");
@@ -221,9 +212,7 @@ contract L2StandardBridge_Test is CommonTest {
 
     /// @dev Tests that `withdrawTo` reverts with custom gas token.
     function test_withdrawToERC20_customGasToken_reverts() external {
-        vm.mockCall(
-            address(l1Block), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(18))
-        );
+        vm.mockCall(address(l1Block), abi.encodeCall(IGasToken.gasPayingToken, ()), abi.encode(address(1), uint8(18)));
         vm.expectRevert("L2StandardBridge: not supported with custom gas token");
         vm.prank(alice, alice);
         l2StandardBridge.withdrawTo(address(L2Token), bob, 1, 1, hex"");
@@ -232,9 +221,7 @@ contract L2StandardBridge_Test is CommonTest {
     /// @dev Tests that `withdrawTo` reverts with custom gas token.
     function test_withdrawToERC20WithValue_customGasToken_reverts() external {
         vm.deal(alice, 1 ether);
-        vm.mockCall(
-            address(l1Block), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(18))
-        );
+        vm.mockCall(address(l1Block), abi.encodeCall(IGasToken.gasPayingToken, ()), abi.encode(address(1), uint8(18)));
         vm.expectRevert("L2StandardBridge: not supported with custom gas token");
         vm.prank(alice, alice);
         l2StandardBridge.withdrawTo{ value: 1 ether }(address(L2Token), bob, 1, 1, hex"");
@@ -243,9 +230,7 @@ contract L2StandardBridge_Test is CommonTest {
     /// @dev Tests that `withdrawTo` with value reverts with custom gas token.
     function test_withdrawTo_customGasTokenWithValue_reverts() external {
         vm.deal(alice, 1 ether);
-        vm.mockCall(
-            address(l1Block), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(18))
-        );
+        vm.mockCall(address(l1Block), abi.encodeCall(IGasToken.gasPayingToken, ()), abi.encode(address(1), uint8(18)));
         vm.expectRevert("L2StandardBridge: not supported with custom gas token");
         vm.prank(alice, alice);
         l2StandardBridge.withdrawTo{ value: 1 ether }(address(Predeploys.LEGACY_ERC20_ETH), bob, 1, 1, hex"");
@@ -577,7 +562,7 @@ contract L2StandardBridge_Bridge_Test is CommonTest {
     /// @dev Tests that bridging reverts with custom gas token.
     function test_bridgeETH_customGasToken_reverts() external {
         vm.prank(alice, alice);
-        vm.mockCall(address(l1Block), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(2)));
+        vm.mockCall(address(l1Block), abi.encodeCall(IGasToken.gasPayingToken, ()), abi.encode(address(1), uint8(2)));
         vm.expectRevert("StandardBridge: cannot bridge ETH with custom gas token");
 
         l2StandardBridge.bridgeETH(50000, hex"dead");
@@ -628,7 +613,7 @@ contract L2StandardBridge_Bridge_Test is CommonTest {
     )
         external
     {
-        vm.mockCall(address(l1Block), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(2)));
+        vm.mockCall(address(l1Block), abi.encodeCall(IGasToken.gasPayingToken, ()), abi.encode(address(1), uint8(2)));
         vm.expectRevert("StandardBridge: cannot bridge ETH with custom gas token");
         vm.deal(address(this), _value);
         l2StandardBridge.bridgeETHTo{ value: _value }(bob, _minGasLimit, _extraData);
@@ -655,22 +640,6 @@ contract L2StandardBridge_FinalizeBridgeETH_Test is CommonTest {
 
         l2StandardBridge.finalizeBridgeETH{ value: 100 }(alice, alice, 100, hex"");
     }
-
-    /// @dev Tests that finalizing bridged reverts with custom gas token.
-    function test_finalizeBridgeETH_customGasToken_reverts() external {
-        address messenger = address(l2StandardBridge.messenger());
-        vm.mockCall(
-            messenger,
-            abi.encodeCall(ICrossDomainMessenger.xDomainMessageSender, ()),
-            abi.encode(address(l2StandardBridge.OTHER_BRIDGE()))
-        );
-        vm.deal(address(l2CrossDomainMessenger), 1);
-        vm.prank(address(l2CrossDomainMessenger));
-        vm.mockCall(address(l1Block), abi.encodeCall(systemConfig.gasPayingToken, ()), abi.encode(address(1), uint8(2)));
-        vm.expectRevert("StandardBridge: cannot bridge ETH with custom gas token");
-
-        l2StandardBridge.finalizeBridgeETH(alice, alice, 1, hex"");
-    }
 }
 
 contract L2StandardBridge_FinalizeBridgeERC20_Test is CommonTest {

packages/contracts-bedrock/test/invariants/SystemConfig.t.sol

@@ -44,8 +44,7 @@ contract SystemConfig_GasLimitBoundaries_Invariant is Test {
                         l1StandardBridge: address(0),
                         disputeGameFactory: address(0),
                         optimismPortal: address(0),
-                        optimismMintableERC20Factory: address(0),
-                        gasPayingToken: Constants.ETHER
+                        optimismMintableERC20Factory: address(0)
                     })
                 )
             )

packages/contracts-bedrock/test/universal/Specs.t.sol

@@ -261,12 +261,6 @@ contract Specification_Test is CommonTest {
         _addSpec({ _name: "OptimismPortalInterop", _sel: _getSel("respectedGameTypeUpdatedAt()") });
         _addSpec({ _name: "OptimismPortalInterop", _sel: _getSel("proofSubmitters(bytes32,uint256)") });
         _addSpec({ _name: "OptimismPortalInterop", _sel: _getSel("numProofSubmitters(bytes32)") });
-        _addSpec({ _name: "OptimismPortalInterop", _sel: _getSel("balance()") });
-        _addSpec({
-            _name: "OptimismPortalInterop",
-            _sel: _getSel("depositERC20Transaction(address,uint256,uint256,uint64,bool,bytes)")
-        });
-        _addSpec({ _name: "OptimismPortalInterop", _sel: _getSel("setGasPayingToken(address,uint8,bytes32,bytes32)") });
         _addSpec({
             _name: "OptimismPortalInterop",
             _sel: IOptimismPortalInterop.setConfig.selector,
@@ -313,12 +307,6 @@ contract Specification_Test is CommonTest {
         _addSpec({ _name: "OptimismPortal2", _sel: _getSel("respectedGameTypeUpdatedAt()") });
         _addSpec({ _name: "OptimismPortal2", _sel: _getSel("proofSubmitters(bytes32,uint256)") });
         _addSpec({ _name: "OptimismPortal2", _sel: _getSel("numProofSubmitters(bytes32)") });
-        _addSpec({ _name: "OptimismPortal2", _sel: _getSel("balance()") });
-        _addSpec({
-            _name: "OptimismPortal2",
-            _sel: _getSel("depositERC20Transaction(address,uint256,uint256,uint64,bool,bytes)")
-        });
-        _addSpec({ _name: "OptimismPortal2", _sel: _getSel("setGasPayingToken(address,uint8,bytes32,bytes32)") });
 
         // ProtocolVersions
         _addSpec({ _name: "ProtocolVersions", _sel: _getSel("RECOMMENDED_SLOT()") });
@@ -395,10 +383,6 @@ contract Specification_Test is CommonTest {
         _addSpec({ _name: "SystemConfig", _sel: _getSel("OPTIMISM_PORTAL_SLOT()") });
         _addSpec({ _name: "SystemConfig", _sel: _getSel("OPTIMISM_MINTABLE_ERC20_FACTORY_SLOT()") });
         _addSpec({ _name: "SystemConfig", _sel: _getSel("BATCH_INBOX_SLOT()") });
-        _addSpec({ _name: "SystemConfig", _sel: _getSel("gasPayingToken()") });
-        _addSpec({ _name: "SystemConfig", _sel: _getSel("gasPayingTokenName()") });
-        _addSpec({ _name: "SystemConfig", _sel: _getSel("gasPayingTokenSymbol()") });
-        _addSpec({ _name: "SystemConfig", _sel: _getSel("isCustomGasToken()") });
         _addSpec({ _name: "SystemConfig", _sel: _getSel("DISPUTE_GAME_FACTORY_SLOT()") });
         _addSpec({ _name: "SystemConfig", _sel: _getSel("disputeGameFactory()") });
         _addSpec({
@@ -471,10 +455,6 @@ contract Specification_Test is CommonTest {
         _addSpec({ _name: "SystemConfigInterop", _sel: _getSel("OPTIMISM_PORTAL_SLOT()") });
         _addSpec({ _name: "SystemConfigInterop", _sel: _getSel("OPTIMISM_MINTABLE_ERC20_FACTORY_SLOT()") });
         _addSpec({ _name: "SystemConfigInterop", _sel: _getSel("BATCH_INBOX_SLOT()") });
-        _addSpec({ _name: "SystemConfigInterop", _sel: _getSel("gasPayingToken()") });
-        _addSpec({ _name: "SystemConfigInterop", _sel: _getSel("gasPayingTokenName()") });
-        _addSpec({ _name: "SystemConfigInterop", _sel: _getSel("gasPayingTokenSymbol()") });
-        _addSpec({ _name: "SystemConfigInterop", _sel: _getSel("isCustomGasToken()") });
         _addSpec({ _name: "SystemConfigInterop", _sel: _getSel("DISPUTE_GAME_FACTORY_SLOT()") });
         _addSpec({ _name: "SystemConfigInterop", _sel: _getSel("disputeGameFactory()") });
         _addSpec({

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

@@ -10,7 +10,6 @@ import { Process } from "scripts/libraries/Process.sol";
 
 // Libraries
 import { LibString } from "@solady/utils/LibString.sol";
-import { Constants } from "src/libraries/Constants.sol";
 import { GameType } from "src/dispute/lib/Types.sol";
 import { EIP1967Helper } from "test/mocks/EIP1967Helper.sol";
 
@@ -183,8 +182,7 @@ contract Initializer_Test is CommonTest {
                             l1StandardBridge: address(0),
                             disputeGameFactory: address(0),
                             optimismPortal: address(0),
-                            optimismMintableERC20Factory: address(0),
-                            gasPayingToken: Constants.ETHER
+                            optimismMintableERC20Factory: address(0)
                         })
                     )
                 )
@@ -219,8 +217,7 @@ contract Initializer_Test is CommonTest {
                             l1StandardBridge: address(0),
                             disputeGameFactory: address(0),
                             optimismPortal: address(0),
-                            optimismMintableERC20Factory: address(0),
-                            gasPayingToken: Constants.ETHER
+                            optimismMintableERC20Factory: address(0)
                         })
                     )
                 )