feat: Move DEFAULT_STARTING_ANCHOR_ROOTS to Constants library (ethere…

…um-optimism#12332)

* feat: Move DEFAULT_STARTING_ANCHOR_ROOTS to Constants library

* feat: Move DEFAULT_STARTING_ANCHOR_ROOTS to scripts/libraries/Constants

* fix: import error

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

@@ -12,8 +12,9 @@ import { BaseDeployIO } from "scripts/utils/BaseDeployIO.sol";
 import { IResourceMetering } from "src/L1/interfaces/IResourceMetering.sol";
 import { ISuperchainConfig } from "src/L1/interfaces/ISuperchainConfig.sol";
 import { IBigStepper } from "src/dispute/interfaces/IBigStepper.sol";
-import { Constants } from "src/libraries/Constants.sol";
 import { Predeploys } from "src/libraries/Predeploys.sol";
+import { Constants } from "src/libraries/Constants.sol";
+import { Constants as ScriptConstants } from "scripts/libraries/Constants.sol";
 
 import { IProxyAdmin } from "src/universal/interfaces/IProxyAdmin.sol";
 import { IProxy } from "src/universal/interfaces/IProxy.sol";
@@ -161,15 +162,10 @@ contract DeployOPChainInput is BaseDeployIO {
         // because to to update to the permissionless game, we will need to update its starting
         // anchor root and deploy a new permissioned dispute game contract anyway.
         //
-        // You can `console.logBytes(abi.encode(defaultStartingAnchorRoots))` to get the bytes that
+        // You can `console.logBytes(abi.encode(ScriptConstants.DEFAULT_STARTING_ANCHOR_ROOTS()))` to get the bytes that
         // are hardcoded into `op-chain-ops/deployer/opcm/opchain.go`
-        IAnchorStateRegistry.StartingAnchorRoot[] memory defaultStartingAnchorRoots =
-            new IAnchorStateRegistry.StartingAnchorRoot[](1);
-        defaultStartingAnchorRoots[0] = IAnchorStateRegistry.StartingAnchorRoot({
-            gameType: GameTypes.PERMISSIONED_CANNON,
-            outputRoot: OutputRoot({ root: Hash.wrap(bytes32(hex"dead")), l2BlockNumber: 0 })
-        });
-        return abi.encode(defaultStartingAnchorRoots);
+
+        return abi.encode(ScriptConstants.DEFAULT_STARTING_ANCHOR_ROOTS());
     }
 
     function opcmProxy() public returns (OPContractsManager) {

packages/contracts-bedrock/scripts/libraries/Constants.sol

@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
+
+import { IAnchorStateRegistry } from "src/dispute/interfaces/IAnchorStateRegistry.sol";
+import { GameTypes, OutputRoot, Hash } from "src/dispute/lib/Types.sol";
+
+/// @title Constants
+/// @notice Constants is a library for storing constants. Simple! Don't put everything in here, just
+///         the stuff used in multiple contracts. Constants that only apply to a single contract
+///         should be defined in that contract instead.
+library Constants {
+    /// @notice Returns the default starting anchor roots value to be used in a new dispute game.
+    function DEFAULT_STARTING_ANCHOR_ROOTS() internal pure returns (IAnchorStateRegistry.StartingAnchorRoot[] memory) {
+        IAnchorStateRegistry.StartingAnchorRoot[] memory defaultStartingAnchorRoots =
+            new IAnchorStateRegistry.StartingAnchorRoot[](1);
+        defaultStartingAnchorRoots[0] = IAnchorStateRegistry.StartingAnchorRoot({
+            gameType: GameTypes.PERMISSIONED_CANNON,
+            outputRoot: OutputRoot({ root: Hash.wrap(bytes32(hex"dead")), l2BlockNumber: 0 })
+        });
+        return defaultStartingAnchorRoots;
+    }
+}