Remove GovernorCountingFractional (Bump OZ to v5.1) (#79)

OpenZeppelin included an implementation of `GovernorCountingFractional` in release [v5.1.0](https://github.com/OpenZeppelin/openzeppelin-contracts/releases/tag/v5.1.0). This PR bumps our OZ dependency to that version and accordingly removes the implementation of `GovernorCountingFractional` which originated in this repo. This PR additionally bumps foundry to v1.9.5.

Author: davidlaprade

.github/workflows/ci.yml

@@ -108,7 +108,7 @@ jobs:
         uses: zgosalvez/github-actions-report-lcov@v2
         with:
           coverage-files: ./lcov.info
-          minimum-coverage: 91 # Set coverage threshold.
+          minimum-coverage: 88 # Set coverage threshold.
 
   slither-analyze:
     runs-on: ubuntu-latest

README.md

@@ -31,7 +31,7 @@ To add Flexible Voting to your own Foundry project, use [forge install](https://
 $ forge install scopelift/flexible-voting
 ```
 
-If you're using a developer framework other than Foundry, we recommend vendoring the code by adding `src/GovernorCountingFractional.sol` and/or `src/FlexVotingClient.sol` to your repo directly. In the future, we may offer an npm package for use with other frameworks.
+If you're using a developer framework other than Foundry, we recommend vendoring the code by adding files like `src/FlexVotingClient.sol` to your repo directly. In the future, we may offer an npm package for use with other frameworks.
 
 ### Constructing a Governor
 
@@ -41,13 +41,11 @@ If you're constructing a new Governor with Flexible Voting—either to upgrade a
 // SPDX-License-Identifier: MIT
 pragma solidity ^0.8.20;
 
+import {Governor} from "@openzeppelin/contracts/governance/Governor.sol";
 import {GovernorVotes} from "@openzeppelin/contracts/governance/extensions/GovernorVotes.sol";
 import {GovernorSettings} from "@openzeppelin/contracts/governance/extensions/GovernorSettings.sol";
-import {GovernorTimelockControl} from
-  "@openzeppelin/contracts/governance/extensions/GovernorTimelockControl.sol";
-import {
-  Governor, GovernorCountingFractional
-} from "flexible-voting/src/GovernorCountingFractional.sol";
+import {GovernorTimelockControl} from "@openzeppelin/contracts/governance/extensions/GovernorTimelockControl.sol";
+import {GovernorCountingFractional} from "@openzeppelin/contracts/governance/extensions/GovernorCountingFractional.sol";
 
 contract FlexibleVotingGovernor is
   GovernorCountingFractional,
@@ -98,11 +96,19 @@ To read more about Flexible Voting adoption, read the documentation pages on [co
 
 ## Repo Contents
 
-* [`src/GovernorCountingFractional.sol`](https://github.com/ScopeLift/flexible-voting/blob/master/src/GovernorCountingFractional.sol) - The Governor extension which enables Flexible Voting. A DAO adopting Flexible Voting would deploy a new Governor which used this extension.
 * [`src/FlexVotingClient.sol`](https://github.com/ScopeLift/flexible-voting/blob/master/src/FlexVotingClient.sol) - An abstract contract designed to make it easy to build clients for Flexible Voting governors. Inherit from this contract if you're building an integration or voting scheme for DAO(s) that use Flexible Voting.
 * [`src/FractionalPool.sol`](https://github.com/ScopeLift/flexible-voting/blob/master/src/FractionalPool.sol) - A proof-of-concept contract demonstrating how Flexible Voting can be used. It implements a simple token pool that allows holders to express their votes on proposals even when their tokens are deposited in the pool.
 * [`test/`](https://github.com/ScopeLift/flexible-voting/tree/master/test) - A full suite of unit and fuzz tests exercising the contracts.
 
+Note that `GovernorCountingFractional` has been removed from this repo.
+[It has since been
+incorporated](https://github.com/OpenZeppelin/openzeppelin-contracts/blob/7b74442c5e87ea51dde41c7f18a209fa5154f1a4/contracts/governance/extensions/GovernorCountingFractional.sol) into [OpenZeppelin's
+contracts library](https://github.com/OpenZeppelin/openzeppelin-contracts)
+as of [v5.1.0](https://github.com/OpenZeppelin/openzeppelin-contracts/releases/tag/v5.1.0).
+If you are unable to use v5.1.0 or later of OpenZeppelin's contracts, you can find the original
+`GovernorCountingFractional` implementation in previous releases of this repo,
+e.g. [`v1.2.0`](https://github.com/ScopeLift/flexible-voting/releases/tag/v1.2.0).
+
 ## Development
 
 This repo is built using [Foundry](https://github.com/foundry-rs/foundry)
@@ -130,4 +136,4 @@ Code contributions to this repo are also welcome! Fork the project, create a new
 
 Fractional Voting is available under the [MIT](LICENSE.txt) license.
 
-Copyright (c) 2023 ScopeLift
+Copyright (c) 2025 ScopeLift

foundry.toml

@@ -21,9 +21,6 @@
 
 [fmt]
   bracket_spacing = false
-  ignore = [
-    'src/GovernorCountingFractional.sol', # Ignored b/c it follows OZ's styleguide.
-  ]
   int_types = "long"
   line_length = 100
   multiline_func_header = "attributes_first"

lib/forge-std

@@ -88,6 +88,9 @@ abstract contract FlexVotingClient {
   /// given time.
   Checkpoints.Trace208 internal totalBalanceCheckpoints;
 
+  // https://github.com/OpenZeppelin/openzeppelin-contracts/blob/7b74442c5e87ea51dde41c7f18a209fa5154f1a4/contracts/governance/extensions/GovernorCountingFractional.sol#L37
+  uint8 internal constant VOTE_TYPE_FRACTIONAL = 255;
+
   error FlexVotingClient__NoVotingWeight();
   error FlexVotingClient__AlreadyVoted();
   error FlexVotingClient__InvalidSupportValue();
@@ -188,17 +191,13 @@ abstract contract FlexVotingClient {
       (_votingWeightAtSnapshot * _proposalVote.abstainVotes) / _totalRawBalanceAtSnapshot
     );
 
-    // This param is ignored by the governor when voting with fractional
-    // weights. It makes no difference what vote type this is.
-    uint8 unusedSupportParam = uint8(VoteType.Abstain);
-
     // Clear the stored votes so that we don't double-cast them.
     delete proposalVotes[proposalId];
 
     bytes memory fractionalizedVotes =
       abi.encodePacked(_againstVotesToCast, _forVotesToCast, _abstainVotesToCast);
     GOVERNOR.castVoteWithReasonAndParams(
-      proposalId, unusedSupportParam, _castVoteReasonString(), fractionalizedVotes
+      proposalId, VOTE_TYPE_FRACTIONAL, _castVoteReasonString(), fractionalizedVotes
     );
   }
 

lib/openzeppelin-contracts

@@ -54,6 +54,9 @@ contract FractionalPool {
   /// @notice Map proposalId to vote totals expressed on this proposal.
   mapping(uint256 => ProposalVote) public proposalVotes;
 
+  // https://github.com/OpenZeppelin/openzeppelin-contracts/blob/7b74442c5e87ea51dde41c7f18a209fa5154f1a4/contracts/governance/extensions/GovernorCountingFractional.sol#L37
+  uint8 internal constant VOTE_TYPE_FRACTIONAL = 255;
+
   /// @param _token The governance token held and lent by this pool.
   /// @param _governor The governor contract associated with this governance token.
   constructor(IVotingToken _token, IFractionalGovernor _governor) {
@@ -122,7 +125,6 @@ contract FractionalPool {
   /// @param proposalId The ID of the proposal which the Pool will now vote on.
   function castVote(uint256 proposalId) external {
     if (internalVotingPeriodEnd(proposalId) > block.number) revert("cannot castVote yet");
-    uint8 unusedSupportParam = uint8(VoteType.Abstain);
     ProposalVote memory _proposalVote = proposalVotes[proposalId];
 
     uint256 _proposalSnapshotBlockNumber = GOVERNOR.proposalSnapshot(proposalId);
@@ -154,7 +156,7 @@ contract FractionalPool {
     bytes memory fractionalizedVotes =
       abi.encodePacked(_againstVotesToCast, _forVotesToCast, _abstainVotesToCast);
     GOVERNOR.castVoteWithReasonAndParams(
-      proposalId, unusedSupportParam, "crowd-sourced vote", fractionalizedVotes
+      proposalId, VOTE_TYPE_FRACTIONAL, "crowd-sourced vote", fractionalizedVotes
     );
   }