maint: add interfaces for governance contracts

Adds interfaces for the two governance contracts.

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

@@ -59,7 +59,7 @@
     "name": "governanceToken",
     "outputs": [
       {
-        "internalType": "contract GovernanceToken",
+        "internalType": "contract IGovernanceToken",
         "name": "",
         "type": "address"
       }

packages/contracts-bedrock/src/governance/MintManager.sol

@@ -1,8 +1,11 @@
 // SPDX-License-Identifier: MIT
 pragma solidity 0.8.15;
 
+// Contracts
 import "@openzeppelin/contracts/access/Ownable.sol";
-import "./GovernanceToken.sol";
+
+// Interfaces
+import { IGovernanceToken } from "src/governance/interfaces/IGovernanceToken.sol";
 
 /// @title MintManager
 /// @notice Set as `owner` of the governance token and responsible for the token inflation
@@ -11,7 +14,7 @@ import "./GovernanceToken.sol";
 ///         token supply. Upgradable to allow changes in the inflation schedule.
 contract MintManager is Ownable {
     /// @notice The GovernanceToken that the MintManager can mint tokens
-    GovernanceToken public immutable governanceToken;
+    IGovernanceToken public immutable governanceToken;
 
     /// @notice The amount of tokens that can be minted per year.
     ///         The value is a fixed point number with 4 decimals.
@@ -32,7 +35,7 @@ contract MintManager is Ownable {
     /// @param _governanceToken The governance token this contract can mint tokens of.
     constructor(address _upgrader, address _governanceToken) {
         transferOwnership(_upgrader);
-        governanceToken = GovernanceToken(_governanceToken);
+        governanceToken = IGovernanceToken(_governanceToken);
     }
 
     /// @notice Only the token owner is allowed to mint a certain amount of the

packages/contracts-bedrock/src/governance/interfaces/IGovernanceToken.sol

@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
+
+import { ERC20Votes } from "@openzeppelin/contracts/token/ERC20/extensions/ERC20Votes.sol";
+
+interface IGovernanceToken {
+    event Approval(address indexed owner, address indexed spender, uint256 value);
+    event DelegateChanged(address indexed delegator, address indexed fromDelegate, address indexed toDelegate);
+    event DelegateVotesChanged(address indexed delegate, uint256 previousBalance, uint256 newBalance);
+    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
+    event Transfer(address indexed from, address indexed to, uint256 value);
+
+    function DOMAIN_SEPARATOR() external view returns (bytes32);
+    function allowance(address owner, address spender) external view returns (uint256);
+    function approve(address spender, uint256 amount) external returns (bool);
+    function balanceOf(address account) external view returns (uint256);
+    function burn(uint256 amount) external;
+    function burnFrom(address account, uint256 amount) external;
+    function checkpoints(address account, uint32 pos) external view returns (ERC20Votes.Checkpoint memory);
+    function decimals() external view returns (uint8);
+    function decreaseAllowance(address spender, uint256 subtractedValue) external returns (bool);
+    function delegate(address delegatee) external;
+    function delegateBySig(address delegatee, uint256 nonce, uint256 expiry, uint8 v, bytes32 r, bytes32 s) external;
+    function delegates(address account) external view returns (address);
+    function getPastTotalSupply(uint256 blockNumber) external view returns (uint256);
+    function getPastVotes(address account, uint256 blockNumber) external view returns (uint256);
+    function getVotes(address account) external view returns (uint256);
+    function increaseAllowance(address spender, uint256 addedValue) external returns (bool);
+    function mint(address _account, uint256 _amount) external;
+    function name() external view returns (string memory);
+    function nonces(address owner) external view returns (uint256);
+    function numCheckpoints(address account) external view returns (uint32);
+    function owner() external view returns (address);
+    function permit(
+        address owner,
+        address spender,
+        uint256 value,
+        uint256 deadline,
+        uint8 v,
+        bytes32 r,
+        bytes32 s
+    )
+        external;
+    function renounceOwnership() external;
+    function symbol() external view returns (string memory);
+    function totalSupply() external view returns (uint256);
+    function transfer(address to, uint256 amount) external returns (bool);
+    function transferFrom(address from, address to, uint256 amount) external returns (bool);
+    function transferOwnership(address newOwner) external;
+}

packages/contracts-bedrock/src/governance/interfaces/IMintManager.sol

@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
+
+import { IGovernanceToken } from "src/governance/interfaces/IGovernanceToken.sol";
+
+interface IMintManager {
+    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
+
+    function DENOMINATOR() external view returns (uint256);
+    function MINT_CAP() external view returns (uint256);
+    function MINT_PERIOD() external view returns (uint256);
+    function governanceToken() external view returns (IGovernanceToken);
+    function mint(address _account, uint256 _amount) external;
+    function mintPermittedAfter() external view returns (uint256);
+    function owner() external view returns (address);
+    function renounceOwnership() external;
+    function transferOwnership(address newOwner) external;
+    function upgrade(address _newMintManager) external;
+}

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

@@ -940,11 +940,12 @@ contract Specification_Test is CommonTest {
 
     /// @notice Ensures that there's an auth spec for every L1 contract function.
     function testContractAuth() public {
-        string[] memory pathExcludes = new string[](4);
+        string[] memory pathExcludes = new string[](5);
         pathExcludes[0] = "src/dispute/interfaces/*";
         pathExcludes[1] = "src/dispute/lib/*";
         pathExcludes[2] = "src/Safe/SafeSigners.sol";
         pathExcludes[3] = "src/L1/interfaces/*";
+        pathExcludes[4] = "src/governance/interfaces/*";
         Abi[] memory abis = ForgeArtifacts.getContractFunctionAbis(
             "src/{L1,dispute,governance,Safe,universal/ProxyAdmin.sol}", pathExcludes
         );

packages/contracts-bedrock/test/governance/MintManager.t.sol

@@ -1,30 +1,32 @@
 // SPDX-License-Identifier: MIT
 pragma solidity 0.8.15;
 
-// Testing utilities
+// Testing
 import { CommonTest } from "test/setup/CommonTest.sol";
 
-// Target contract dependencies
+// Contracts
 import { GovernanceToken } from "src/governance/GovernanceToken.sol";
-
-// Target contract
 import { MintManager } from "src/governance/MintManager.sol";
 
+// Interfaces
+import { IGovernanceToken } from "src/governance/interfaces/IGovernanceToken.sol";
+import { IMintManager } from "src/governance/interfaces/IMintManager.sol";
+
 contract MintManager_Initializer is CommonTest {
     address constant owner = address(0x1234);
     address constant rando = address(0x5678);
-    GovernanceToken internal gov;
-    MintManager internal manager;
+    IGovernanceToken internal gov;
+    IMintManager internal manager;
 
     /// @dev Sets up the test suite.
     function setUp() public virtual override {
         super.setUp();
 
         vm.prank(owner);
-        gov = new GovernanceToken();
+        gov = IGovernanceToken(address(new GovernanceToken()));
 
         vm.prank(owner);
-        manager = new MintManager(owner, address(gov));
+        manager = IMintManager(address(new MintManager(owner, address(gov))));
 
         vm.prank(owner);
         gov.transferOwnership(address(manager));

packages/contracts-bedrock/test/setup/Setup.sol

@@ -24,7 +24,6 @@ import { L1FeeVault } from "src/L2/L1FeeVault.sol";
 import { GasPriceOracle } from "src/L2/GasPriceOracle.sol";
 import { L1Block } from "src/L2/L1Block.sol";
 import { LegacyMessagePasser } from "src/legacy/LegacyMessagePasser.sol";
-import { GovernanceToken } from "src/governance/GovernanceToken.sol";
 import { FeeVault } from "src/universal/FeeVault.sol";
 import { WETH } from "src/L2/WETH.sol";
 import { SuperchainWETH } from "src/L2/SuperchainWETH.sol";
@@ -52,6 +51,7 @@ import { IL1ERC721Bridge } from "src/L1/interfaces/IL1ERC721Bridge.sol";
 import { IOptimismMintableERC20Factory } from "src/universal/interfaces/IOptimismMintableERC20Factory.sol";
 import { IAddressManager } from "src/legacy/interfaces/IAddressManager.sol";
 import { IOptimismERC20Factory } from "src/L2/interfaces/IOptimismERC20Factory.sol";
+import { IGovernanceToken } from "src/governance/interfaces/IGovernanceToken.sol";
 
 /// @title Setup
 /// @dev This contact is responsible for setting up the contracts in state. It currently
@@ -105,7 +105,7 @@ contract Setup {
     GasPriceOracle gasPriceOracle = GasPriceOracle(Predeploys.GAS_PRICE_ORACLE);
     L1Block l1Block = L1Block(Predeploys.L1_BLOCK_ATTRIBUTES);
     LegacyMessagePasser legacyMessagePasser = LegacyMessagePasser(Predeploys.LEGACY_MESSAGE_PASSER);
-    GovernanceToken governanceToken = GovernanceToken(Predeploys.GOVERNANCE_TOKEN);
+    IGovernanceToken governanceToken = IGovernanceToken(Predeploys.GOVERNANCE_TOKEN);
     WETH weth = WETH(payable(Predeploys.WETH));
     SuperchainWETH superchainWeth = SuperchainWETH(payable(Predeploys.SUPERCHAIN_WETH));
     ETHLiquidity ethLiquidity = ETHLiquidity(Predeploys.ETH_LIQUIDITY);