feat(community): disable x/distribution community tax in disable inflation upgrade (#1752)

* Disable distribution community tax in disable inflation upgrade

* Add changelog entry

CHANGELOG.md

@@ -38,7 +38,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ### Features
 
-- (metrics) [#1668] Adds non-state breaking x/metrics module for custom telemetry.
+- (metrics) [#1668] Adds non-state breaking x/metrics module for custom telemetry
 - (metrics) [#1669] Add performance timing metrics to all Begin/EndBlockers
 - (community) [#1704] Add module params
 - (community) [#1706] Add disable inflation upgrade
@@ -52,8 +52,9 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 - (community) [#1704] Add param to control when inflation will be disabled
 - (community) [#1707] Default staking rewards per second set to `744191`
-- (community) [#1706] Add disable inflation upgrade to begin blocker that updates x/mint and x/kavadist params.
+- (community) [#1706] Add disable inflation upgrade to begin blocker that updates x/mint and x/kavadist params
 - (community) [#1729] Consolidate community funds from `x/distribution` and `x/kavadist` to `x/community`
+- (community) [#1752] Set `x/distribution` CommunityTax to zero on inflation disable upgrade
 
 ## [v0.24.0]
 
@@ -294,10 +295,12 @@ the [changelog](https://github.com/cosmos/cosmos-sdk/blob/v0.38.4/CHANGELOG.md).
 - [#257](https://github.com/Kava-Labs/kava/pulls/257) Include scripts to run
   large-scale simulations remotely using aws-batch
 
+[#1752]: https://github.com/Kava-Labs/kava/pull/1752
 [#1729]: https://github.com/Kava-Labs/kava/pull/1729
 [#1745]: https://github.com/Kava-Labs/kava/pull/1745
 [#1707]: https://github.com/Kava-Labs/kava/pull/1707
 [#1706]: https://github.com/Kava-Labs/kava/pull/1706
+[#1704]: https://github.com/Kava-Labs/kava/pull/1704
 [#1668]: https://github.com/Kava-Labs/kava/pull/1668
 [#1669]: https://github.com/Kava-Labs/kava/pull/1669
 [#1655]: https://github.com/Kava-Labs/kava/pull/1655

x/community/keeper/disable_inflation.go

@@ -19,8 +19,14 @@ func (k Keeper) CheckAndDisableMintAndKavaDistInflation(ctx sdk.Context) {
 		return
 	}
 
+	logger := k.Logger(ctx)
+	logger.Info("disable inflation upgrade started")
+
 	// run disable inflation logic
 	k.disableInflation(ctx)
+	k.disableCommunityTax(ctx)
+
+	logger.Info("disable inflation upgrade finished successfully!")
 
 	ctx.EventManager().EmitEvent(
 		sdk.NewEvent(
@@ -43,7 +49,6 @@ func (k Keeper) CheckAndDisableMintAndKavaDistInflation(ctx sdk.Context) {
 // affecting rewards.  In addition, inflation periods in kavadist should be removed.
 func (k Keeper) disableInflation(ctx sdk.Context) {
 	logger := k.Logger(ctx)
-	logger.Info("disable inflation upgrade started")
 
 	// set x/min inflation to 0
 	mintParams := k.mintKeeper.GetParams(ctx)
@@ -57,6 +62,14 @@ func (k Keeper) disableInflation(ctx sdk.Context) {
 	kavadistParams.Active = false
 	k.kavadistKeeper.SetParams(ctx, kavadistParams)
 	logger.Info("x/kavadist inflation disabled")
-
-	logger.Info("disable inflation upgrade finished successfully!")
+}
+
+// disableCommunityTax sets x/distribution Params.CommunityTax to 0
+func (k Keeper) disableCommunityTax(ctx sdk.Context) {
+	logger := k.Logger(ctx)
+
+	distrParams := k.distrKeeper.GetParams(ctx)
+	distrParams.CommunityTax = sdk.ZeroDec()
+	k.distrKeeper.SetParams(ctx, distrParams)
+	logger.Info("x/distribution community tax set to 0")
 }

x/community/testutil/disable_inflation.go

@@ -4,6 +4,7 @@ import (
 	"time"
 
 	sdk "github.com/cosmos/cosmos-sdk/types"
+	distrtypes "github.com/cosmos/cosmos-sdk/x/distribution/types"
 	minttypes "github.com/cosmos/cosmos-sdk/x/mint/types"
 	"github.com/stretchr/testify/suite"
 	tmproto "github.com/tendermint/tendermint/proto/tendermint/types"
@@ -29,6 +30,7 @@ type disableInflationTestSuite struct {
 
 	genesisMintState     *minttypes.GenesisState
 	genesisKavadistState *kavadisttypes.GenesisState
+	genesisDistrState    *distrtypes.GenesisState
 
 	testFunc testFunc
 }
@@ -57,10 +59,15 @@ func (suite *disableInflationTestSuite) SetupTest() {
 	kavadistGen.Params.Active = true
 	suite.genesisKavadistState = kavadistGen
 
+	distrGen := distrtypes.DefaultGenesisState()
+	distrGen.Params.CommunityTax = sdk.MustNewDecFromStr("0.949500000000000000")
+	suite.genesisDistrState = distrGen
+
 	appCodec := tApp.AppCodec()
 	suite.App.InitializeFromGenesisStates(
 		app.GenesisState{minttypes.ModuleName: appCodec.MustMarshalJSON(mintGen)},
 		app.GenesisState{kavadisttypes.ModuleName: appCodec.MustMarshalJSON(kavadistGen)},
+		app.GenesisState{distrtypes.ModuleName: appCodec.MustMarshalJSON(distrGen)},
 	)
 }
 
@@ -70,10 +77,12 @@ func (suite *disableInflationTestSuite) TestDisableInflation() {
 		suite.Require().True(found)
 		mintParams := suite.App.GetMintKeeper().GetParams(suite.Ctx)
 		kavadistParams := suite.App.GetKavadistKeeper().GetParams(suite.Ctx)
+		distrParams := suite.App.GetDistrKeeper().GetParams(suite.Ctx)
 
 		disableTimeMsg := "expected inflation disable time to match"
 		expectedMintState := suite.genesisMintState
 		expectedKavadistState := suite.genesisKavadistState
+		expectedDistrState := suite.genesisDistrState
 		expectedStakingRewards := originalStakingRewards
 		msgSuffix := "before upgrade"
 
@@ -92,6 +101,9 @@ func (suite *disableInflationTestSuite) TestDisableInflation() {
 			expectedMintState.Params.InflationMax = sdk.ZeroDec()
 
 			expectedKavadistState.Params.Active = false
+
+			expectedDistrState.Params.CommunityTax = sdk.ZeroDec()
+
 			msgSuffix = "after upgrade"
 
 			suite.Require().NoError(app.EventsContains(suite.Ctx.EventManager().Events(), sdk.NewEvent(types.EventTypeInflationStop)))
@@ -100,6 +112,7 @@ func (suite *disableInflationTestSuite) TestDisableInflation() {
 		suite.Require().Equal(expectedMintState.Params.InflationMin, mintParams.InflationMin, msg+": expected mint inflation min to match state "+msgSuffix)
 		suite.Require().Equal(expectedMintState.Params.InflationMax, mintParams.InflationMax, msg+": expected mint inflation max to match state "+msgSuffix)
 		suite.Require().Equal(expectedKavadistState.Params.Active, kavadistParams.Active, msg+":expected kavadist active flag match state "+msgSuffix)
+		suite.Require().Equal(expectedDistrState.Params.CommunityTax, distrParams.CommunityTax, msg+":expected x/distribution community tax to match state "+msgSuffix)
 		suite.Require().Equal(expectedDisableTime, params.UpgradeTimeDisableInflation, msg+": "+disableTimeMsg)
 
 		// we always check staking rewards per second matches the passed in expectation

x/community/types/expected_keepers.go

@@ -43,6 +43,8 @@ type DistributionKeeper interface {
 	GetFeePoolCommunityCoins(ctx sdk.Context) sdk.DecCoins
 	GetFeePool(ctx sdk.Context) distrtypes.FeePool
 	SetFeePool(ctx sdk.Context, feePool distrtypes.FeePool)
+	GetParams(ctx sdk.Context) distrtypes.Params
+	SetParams(ctx sdk.Context, params distrtypes.Params)
 }
 
 type MintKeeper interface {