[R4R] fix: match reward payouts to current harvest v1 payouts (#786)

* fix: payout rewards on 1st or 15th of month

* backport payout test

* fix: add default case

x/incentive/keeper/payout.go

@@ -1,6 +1,8 @@
 package keeper
 
 import (
+	"time"
+
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
 	"github.com/cosmos/cosmos-sdk/x/auth"
@@ -12,6 +14,15 @@ import (
 	validatorvesting "github.com/kava-labs/kava/x/validator-vesting"
 )
 
+const (
+	// BeginningOfMonth harvest rewards that are claimed after the 15th at 14:00UTC of the month always vest on the first of the month
+	BeginningOfMonth = 1
+	// MidMonth harvest rewards that are claimed before the 15th at 14:00UTC of the month always vest on the 15 of the month
+	MidMonth = 15
+	// PaymentHour harvest rewards always vest at 14:00UTC
+	PaymentHour = 14
+)
+
 // ClaimUSDXMintingReward sends the reward amount to the input address and zero's out the claim in the store
 func (k Keeper) ClaimUSDXMintingReward(ctx sdk.Context, addr sdk.AccAddress, multiplierName types.MultiplierName) error {
 	claim, found := k.GetUSDXMintingClaim(ctx, addr)
@@ -40,7 +51,10 @@ func (k Keeper) ClaimUSDXMintingReward(ctx sdk.Context, addr sdk.AccAddress, mul
 		return types.ErrZeroClaim
 	}
 	rewardCoin := sdk.NewCoin(claim.Reward.Denom, rewardAmount)
-	length := ctx.BlockTime().AddDate(0, int(multiplier.MonthsLockup), 0).Unix() - ctx.BlockTime().Unix()
+	length, err := k.GetPeriodLength(ctx, multiplier)
+	if err != nil {
+		return err
+	}
 
 	err = k.SendTimeLockedCoinsToAccount(ctx, types.IncentiveMacc, addr, sdk.NewCoins(rewardCoin), length)
 	if err != nil {
@@ -93,9 +107,12 @@ func (k Keeper) ClaimHardReward(ctx sdk.Context, addr sdk.AccAddress, multiplier
 		}
 		rewardCoins = append(rewardCoins, sdk.NewCoin(coin.Denom, rewardAmount))
 	}
-	length := ctx.BlockTime().AddDate(0, int(multiplier.MonthsLockup), 0).Unix() - ctx.BlockTime().Unix()
+	length, err := k.GetPeriodLength(ctx, multiplier)
+	if err != nil {
+		return err
+	}
 
-	err := k.SendTimeLockedCoinsToAccount(ctx, types.IncentiveMacc, addr, rewardCoins, length)
+	err = k.SendTimeLockedCoinsToAccount(ctx, types.IncentiveMacc, addr, rewardCoins, length)
 	if err != nil {
 		return err
 	}
@@ -170,6 +187,29 @@ func (k Keeper) SendTimeLockedCoinsToBaseAccount(ctx sdk.Context, senderModule s
 	return nil
 }
 
+// GetPeriodLength returns the length of the period based on the input blocktime and multiplier
+// note that pay dates are always the 1st or 15th of the month at 14:00UTC.
+func (k Keeper) GetPeriodLength(ctx sdk.Context, multiplier types.Multiplier) (int64, error) {
+
+	if multiplier.MonthsLockup == 0 {
+		return 0, nil
+	}
+	switch multiplier.Name {
+	case types.Small, types.Medium, types.Large:
+		currentDay := ctx.BlockTime().Day()
+		payDay := BeginningOfMonth
+		monthOffset := int64(1)
+		if currentDay < MidMonth || (currentDay == MidMonth && ctx.BlockTime().Hour() < PaymentHour) {
+			payDay = MidMonth
+			monthOffset = int64(0)
+		}
+		periodEndDate := time.Date(ctx.BlockTime().Year(), ctx.BlockTime().Month(), payDay, PaymentHour, 0, 0, 0, time.UTC).AddDate(0, int(multiplier.MonthsLockup+monthOffset), 0)
+		return periodEndDate.Unix() - ctx.BlockTime().Unix(), nil
+	default:
+		return 0, types.ErrInvalidMultiplier
+	}
+}
+
 // addCoinsToVestingSchedule adds coins to the input account's vesting schedule where length is the amount of time (from the current block time), in seconds, that the coins will be vesting for
 // the input address must be a periodic vesting account
 func (k Keeper) addCoinsToVestingSchedule(ctx sdk.Context, addr sdk.AccAddress, amt sdk.Coins, length int64) {

x/incentive/keeper/payout_test.go

@@ -2,7 +2,6 @@ package keeper_test
 
 import (
 	"errors"
-	"fmt"
 	"strings"
 	"time"
 
@@ -55,7 +54,7 @@ func (suite *KeeperTestSuite) TestPayoutUSDXMintingClaim() {
 				multiplier:               types.MultiplierName("large"),
 				timeElapsed:              86400,
 				expectedBalance:          cs(c("usdx", 10000000000), c("ukava", 10576385600)),
-				expectedPeriods:          vesting.Periods{vesting.Period{Length: 31536000, Amount: cs(c("ukava", 10571385600))}},
+				expectedPeriods:          vesting.Periods{vesting.Period{Length: 32918400, Amount: cs(c("ukava", 10571385600))}},
 				isPeriodicVestingAccount: true,
 			},
 			errArgs{
@@ -144,7 +143,6 @@ func (suite *KeeperTestSuite) TestPayoutUSDXMintingClaim() {
 				}
 
 				claim, found := suite.keeper.GetUSDXMintingClaim(suite.ctx, suite.addrs[0])
-				fmt.Println(claim)
 				suite.Require().True(found)
 				suite.Require().Equal(c("ukava", 0), claim.Reward)
 			} else {
@@ -678,3 +676,142 @@ func (suite *KeeperTestSuite) SetupWithAccountState() {
 	suite.ctx = ctx
 	suite.addrs = addrs
 }
+
+func (suite *KeeperTestSuite) TestGetPeriodLength() {
+	type args struct {
+		blockTime      time.Time
+		multiplier     types.Multiplier
+		expectedLength int64
+	}
+	type errArgs struct {
+		expectPass bool
+		contains   string
+	}
+	type periodTest struct {
+		name    string
+		args    args
+		errArgs errArgs
+	}
+	testCases := []periodTest{
+		{
+			name: "first half of month",
+			args: args{
+				blockTime:      time.Date(2020, 11, 2, 15, 0, 0, 0, time.UTC),
+				multiplier:     types.NewMultiplier(types.Medium, 6, sdk.MustNewDecFromStr("0.333333")),
+				expectedLength: time.Date(2021, 5, 15, 14, 0, 0, 0, time.UTC).Unix() - time.Date(2020, 11, 2, 15, 0, 0, 0, time.UTC).Unix(),
+			},
+			errArgs: errArgs{
+				expectPass: true,
+				contains:   "",
+			},
+		},
+		{
+			name: "first half of month long lockup",
+			args: args{
+				blockTime:      time.Date(2020, 11, 2, 15, 0, 0, 0, time.UTC),
+				multiplier:     types.NewMultiplier(types.Medium, 24, sdk.MustNewDecFromStr("0.333333")),
+				expectedLength: time.Date(2022, 11, 15, 14, 0, 0, 0, time.UTC).Unix() - time.Date(2020, 11, 2, 15, 0, 0, 0, time.UTC).Unix(),
+			},
+			errArgs: errArgs{
+				expectPass: true,
+				contains:   "",
+			},
+		},
+		{
+			name: "second half of month",
+			args: args{
+				blockTime:      time.Date(2020, 12, 31, 15, 0, 0, 0, time.UTC),
+				multiplier:     types.NewMultiplier(types.Medium, 6, sdk.MustNewDecFromStr("0.333333")),
+				expectedLength: time.Date(2021, 7, 1, 14, 0, 0, 0, time.UTC).Unix() - time.Date(2020, 12, 31, 15, 0, 0, 0, time.UTC).Unix(),
+			},
+			errArgs: errArgs{
+				expectPass: true,
+				contains:   "",
+			},
+		},
+		{
+			name: "second half of month long lockup",
+			args: args{
+				blockTime:      time.Date(2020, 12, 31, 15, 0, 0, 0, time.UTC),
+				multiplier:     types.NewMultiplier(types.Large, 24, sdk.MustNewDecFromStr("0.333333")),
+				expectedLength: time.Date(2023, 1, 1, 14, 0, 0, 0, time.UTC).Unix() - time.Date(2020, 12, 31, 15, 0, 0, 0, time.UTC).Unix(),
+			},
+			errArgs: errArgs{
+				expectPass: true,
+				contains:   "",
+			},
+		},
+		{
+			name: "end of feb",
+			args: args{
+				blockTime:      time.Date(2021, 2, 28, 15, 0, 0, 0, time.UTC),
+				multiplier:     types.NewMultiplier(types.Medium, 6, sdk.MustNewDecFromStr("0.333333")),
+				expectedLength: time.Date(2021, 9, 1, 14, 0, 0, 0, time.UTC).Unix() - time.Date(2021, 2, 28, 15, 0, 0, 0, time.UTC).Unix(),
+			},
+			errArgs: errArgs{
+				expectPass: true,
+				contains:   "",
+			},
+		},
+		{
+			name: "leap year",
+			args: args{
+				blockTime:      time.Date(2020, 2, 29, 15, 0, 0, 0, time.UTC),
+				multiplier:     types.NewMultiplier(types.Medium, 6, sdk.MustNewDecFromStr("0.333333")),
+				expectedLength: time.Date(2020, 9, 1, 14, 0, 0, 0, time.UTC).Unix() - time.Date(2020, 2, 29, 15, 0, 0, 0, time.UTC).Unix(),
+			},
+			errArgs: errArgs{
+				expectPass: true,
+				contains:   "",
+			},
+		},
+		{
+			name: "leap year long lockup",
+			args: args{
+				blockTime:      time.Date(2020, 2, 29, 15, 0, 0, 0, time.UTC),
+				multiplier:     types.NewMultiplier(types.Large, 24, sdk.MustNewDecFromStr("1")),
+				expectedLength: time.Date(2022, 3, 1, 14, 0, 0, 0, time.UTC).Unix() - time.Date(2020, 2, 29, 15, 0, 0, 0, time.UTC).Unix(),
+			},
+			errArgs: errArgs{
+				expectPass: true,
+				contains:   "",
+			},
+		},
+		{
+			name: "exactly half of month",
+			args: args{
+				blockTime:      time.Date(2020, 12, 15, 14, 0, 0, 0, time.UTC),
+				multiplier:     types.NewMultiplier(types.Medium, 6, sdk.MustNewDecFromStr("0.333333")),
+				expectedLength: time.Date(2021, 7, 1, 14, 0, 0, 0, time.UTC).Unix() - time.Date(2020, 12, 15, 14, 0, 0, 0, time.UTC).Unix(),
+			},
+			errArgs: errArgs{
+				expectPass: true,
+				contains:   "",
+			},
+		},
+		{
+			name: "just before half of month",
+			args: args{
+				blockTime:      time.Date(2020, 12, 15, 13, 59, 59, 0, time.UTC),
+				multiplier:     types.NewMultiplier(types.Medium, 6, sdk.MustNewDecFromStr("0.333333")),
+				expectedLength: time.Date(2021, 6, 15, 14, 0, 0, 0, time.UTC).Unix() - time.Date(2020, 12, 15, 13, 59, 59, 0, time.UTC).Unix(),
+			},
+			errArgs: errArgs{
+				expectPass: true,
+				contains:   "",
+			},
+		},
+	}
+	for _, tc := range testCases {
+		suite.Run(tc.name, func() {
+			ctx := suite.ctx.WithBlockTime(tc.args.blockTime)
+			length, err := suite.keeper.GetPeriodLength(ctx, tc.args.multiplier)
+			if tc.errArgs.expectPass {
+				suite.Require().NoError(err)
+				suite.Require().Equal(tc.args.expectedLength, length)
+			} else {
+				suite.Require().Error(err)
+			}
+		})
+	}
+}