Fix short gov fee in HyperdriveUtils to match HyperdriveBase

[dpaiton]

Description

The gov fee for shorts in HyperdriveUtils.sol did not match the behavior in HyperdriveBase.sol:

HyperdriveUtils.sol:

    /// @dev Gets the governance fee paid by the trader when they open a short.
    /// @param _bondAmount The bond amount.
    /// @param _spotPrice The spot price.
    /// @param _curveFee The curve fee parameter.
    /// @param _governanceLPFee The governance fee parameter.
    /// @return The governance fee.
    function calculateShortGovernanceFee(
        uint256 _bondAmount,
        uint256 _spotPrice,
        uint256 _curveFee,
        uint256 _governanceLPFee
    ) internal pure returns (uint256) {
        return
            calculateShortCurveFee(_bondAmount, _spotPrice, _curveFee).mulUp(
                _governanceLPFee
            );
    }

It is mulDown in HyperdriveBase.sol::_calculateFeesGivenBonds:

        // NOTE: Round down to underestimate the governance curve fee.
        //
        // Calculate the curve portion of the governance fee:
        //
        // governanceCurveFee = curve_fee * phi_gov
        //                    = shares * phi_gov
        governanceCurveFee = curveFee.mulDown(_governanceLPFee);

Review Checklists

Please check each item before approving the pull request. While going through the checklist, it is recommended to leave comments on items that are referenced in the checklist to make sure that they are reviewed. If there are multiple reviewers, copy the checklists into sections titled ## [Reviewer Name]. If the PR doesn't touch Solidity and/or Rust, the corresponding checklist can be removed.

[[Reviewer Name]]

• [ ] Tokens
  • [ ] Do all approve calls use forceApprove?
  • [ ] Do all transfer calls use safeTransfer?
  • [ ] Do all transferFrom calls use msg.sender as the from address?
    • [ ] If not, is the function access restricted to prevent unauthorized token spend?
• [ ] Low-level calls (call, delegatecall, staticcall, transfer, send)
  • [ ] Is the returned success boolean checked to handle failed calls?
  • [ ] If using delegatecall, are there strict access controls on the addresses that can be called? It shouldn't be possible to delegatecall arbitrary addresses, so the list of possible targets should either be immutable or tightly controlled by an admin.
• [ ] Reentrancy
  • [ ] Are functions that make external calls or transfer ether marked as nonReentrant?
    • [ ] If not, is there documentation that explains why reentrancy is not a concern or how it's mitigated?
• [ ] Gas Optimizations
  • [ ] Is the logic as simple as possible?
  • [ ] Are the storage values that are used repeatedly cached in stack or memory variables?
  • [ ] If loops are used, are there guards in place to avoid out-of-gas issues?
• [ ] Visibility
  • [ ] Are all payable functions restricted to avoid stuck ether?
• [ ] Math
  • [ ] Is all of the arithmetic checked or guarded by if-statements that will catch underflows?
  • [ ] If Safe functions are altered, are potential underflows and overflows caught so that a failure flag can be thrown?
  • [ ] Are all of the rounding directions clearly documented?
• [ ] Testing
  • [ ] Are there new or updated unit or integration tests?
  • [ ] Do the tests cover the happy paths?
  • [ ] Do the tests cover the unhappy paths?
  • [ ] Are there an adequate number of fuzz tests to ensure that we are covering the full input space?

[coveralls]

Pull Request Test Coverage Report for Build 9103997832

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage decreased (-0.05%) to 93.377%

---

Files with Coverage Reduction	New Missed Lines	%
contracts/src/libraries/LPMath.sol	1	84.29%
<!--	Total:	1		-->

Totals
Change from base Build 9082782840:	-0.05%
Covered Lines:	1833
Relevant Lines:	1963

---

💛 - Coveralls

[github-actions[bot]]

Hyperdrive Gas Benchmark

Benchmark suite	Current: f2754a5810ab3e07ae8fe061c1c544cfa8127680	Previous: a98362d1ead7c068957d1bdcfed9c6d7b0c7e4e8	Deviation	Status
addLiquidity: min	33827 gas	33827 gas	0%	🟰
addLiquidity: avg	155693 gas	156586 gas	-0.5703%	✅
addLiquidity: max	428173 gas	428173 gas	0%	🟰
checkpoint: min	40292 gas	40292 gas	0%	🟰
checkpoint: avg	142347 gas	142307 gas	0.0281%	🚨
checkpoint: max	253424 gas	253424 gas	0%	🟰
closeLong: min	31361 gas	31361 gas	0%	🟰
closeLong: avg	134709 gas	134588 gas	0.0899%	🚨
closeLong: max	2625796 gas	2625796 gas	0%	🟰
closeShort: min	31349 gas	31349 gas	0%	🟰
closeShort: avg	131198 gas	131061 gas	0.1045%	🚨
closeShort: max	401270 gas	262372 gas	52.9393%	🚨
initialize: min	31371 gas	31371 gas	0%	🟰
initialize: avg	330070 gas	330036 gas	0.0103%	🚨
initialize: max	396015 gas	396015 gas	0%	🟰
openLong: min	33370 gas	33370 gas	0%	🟰
openLong: avg	172818 gas	172540 gas	0.1611%	🚨
openLong: max	306039 gas	306039 gas	0%	🟰
openShort: min	33936 gas	33936 gas	0%	🟰
openShort: avg	167627 gas	167571 gas	0.0334%	🚨
openShort: max	412540 gas	414992 gas	-0.5909%	✅
redeemWithdrawalShares: min	31251 gas	31251 gas	0%	🟰
redeemWithdrawalShares: avg	74462 gas	73794 gas	0.9052%	🚨
redeemWithdrawalShares: max	209214 gas	209214 gas	0%	🟰
removeLiquidity: min	31301 gas	31301 gas	0%	🟰
removeLiquidity: avg	208305 gas	209011 gas	-0.3378%	✅
removeLiquidity: max	403026 gas	403038 gas	-0.0030%	✅

This comment was automatically generated by workflow using github-action-benchmark.