DRAFT: require noun age to fork

packages/nouns-contracts/contracts/governance/NounsDAOInterfaces.sol

@@ -696,6 +696,8 @@ contract NounsDAOStorageV3 {
         INounsDAOForkEscrow forkEscrow;
         /// @notice address of the DAO's fork deployer contract
         IForkDAODeployer forkDAODeployer;
+        /// @notice the age of a noun, in noun ids, for a noun to be allowed to fork
+        uint16 nounAgeRequiredToFork;
         /// @notice ERC20 tokens to include when sending funds to a deployed fork
         address[] erc20TokensToIncludeInFork;
         /// @notice The treasury contract of the last deployed fork

packages/nouns-contracts/contracts/governance/NounsDAOLogicV3.sol

@@ -803,6 +803,10 @@ contract NounsDAOLogicV3 is NounsDAOStorageV3, NounsDAOEventsV3 {
         ds._setForkThresholdBPS(newForkThresholdBPS);
     }
 
+    function _setNounAgeRequiredToFork(uint16 newNounAgeRequiredToFork) external {
+        ds._setNounAgeRequiredToFork(newNounAgeRequiredToFork);
+    }
+
     /**
      * @notice Admin function for setting the proposal id at which vote snapshots start using the voting start block
      * instead of the proposal creation block.

packages/nouns-contracts/contracts/governance/NounsDAOV3Admin.sol

@@ -108,6 +108,8 @@ library NounsDAOV3Admin {
     /// @notice Emitted when the main timelock, timelockV1 and admin are set
     event TimelocksAndAdminSet(address timelock, address timelockV1, address admin);
 
+    event NounAgeRequiredToForkSet(uint16 oldNounAgeRequiredToFork, uint16 newNounAgeRequiredToFork);
+
     /// @notice The minimum setable proposal threshold
     uint256 public constant MIN_PROPOSAL_THRESHOLD_BPS = 1; // 1 basis point or 0.01%
 
@@ -557,6 +559,15 @@ library NounsDAOV3Admin {
         ds.forkThresholdBPS = newForkThresholdBPS;
     }
 
+    function _setNounAgeRequiredToFork(NounsDAOStorageV3.StorageV3 storage ds, uint16 newNounAgeRequiredToFork)
+        external
+        onlyAdmin(ds)
+    {
+        emit NounAgeRequiredToForkSet(ds.nounAgeRequiredToFork, newNounAgeRequiredToFork);
+
+        ds.nounAgeRequiredToFork = newNounAgeRequiredToFork;
+    }
+
     /**
      * @notice Admin function for setting the timelocks and admin
      * @param timelock the new timelock contract

packages/nouns-contracts/contracts/governance/fork/NounsDAOV3Fork.sol

@@ -20,13 +20,15 @@ pragma solidity ^0.8.19;
 import { NounsDAOStorageV3, INounsDAOForkEscrow, INounsDAOExecutorV2 } from '../NounsDAOInterfaces.sol';
 import { IERC20 } from '@openzeppelin/contracts/token/ERC20/IERC20.sol';
 import { NounsTokenFork } from './newdao/token/NounsTokenFork.sol';
+import { INounsAuctionHouseV2 } from '../../interfaces/INounsAuctionHouseV2.sol';
 
 library NounsDAOV3Fork {
     error ForkThresholdNotMet();
     error ForkPeriodNotActive();
     error ForkPeriodActive();
     error AdminOnly();
     error UseAlternativeWithdrawFunction();
+    error NounIdNotOldEnough();
 
     /// @notice Emitted when someones adds nouns to the fork escrow
     event EscrowedToFork(
@@ -81,6 +83,7 @@ library NounsDAOV3Fork {
         INounsDAOForkEscrow forkEscrow = ds.forkEscrow;
 
         for (uint256 i = 0; i < tokenIds.length; i++) {
+            checkNounIdIsAllowedToFork(ds, tokenIds[i]);
             ds.nouns.safeTransferFrom(msg.sender, address(forkEscrow), tokenIds[i]);
         }
 
@@ -151,6 +154,7 @@ library NounsDAOV3Fork {
         sendProRataTreasury(ds, ds.forkDAOTreasury, tokenIds.length, adjustedTotalSupply(ds));
 
         for (uint256 i = 0; i < tokenIds.length; i++) {
+            checkNounIdIsAllowedToFork(ds, tokenIds[i]);
             ds.nouns.transferFrom(msg.sender, timelock, tokenIds[i]);
         }
 
@@ -216,6 +220,11 @@ library NounsDAOV3Fork {
         return ds.forkEscrow.numTokensInEscrow();
     }
 
+    function checkNounIdIsAllowedToFork(NounsDAOStorageV3.StorageV3 storage ds, uint256 tokenId) internal view {
+        uint256 auctionedNounId = INounsAuctionHouseV2(ds.nouns.minter()).auction().nounId;
+        if (tokenId < auctionedNounId - ds.nounAgeRequiredToFork) revert NounIdNotOldEnough();
+    }
+
     /**
      * @notice Returns the number of nouns in supply minus nouns owned by the DAO, i.e. held in the treasury or in an
      * escrow after it has closed.