From 0ec5a214b52b055640a76e5206d1ea87ec6520be Mon Sep 17 00:00:00 2001
From: Yun <yun@terra.money>
Date: Wed, 20 Nov 2019 11:06:15 +0900
Subject: [PATCH 1/2] fix to apply reward spread by multiplication

---
 x/oracle/abci_test.go | 44 ++++++++++++++++++++++++++++++++++++++++++-
 x/oracle/tally.go     |  5 ++++-
 2 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/x/oracle/abci_test.go b/x/oracle/abci_test.go
index 1332e0064..deb6db87e 100644
--- a/x/oracle/abci_test.go
+++ b/x/oracle/abci_test.go
@@ -233,7 +233,7 @@ func TestOracleTally(t *testing.T) {
 	rewardees := []sdk.AccAddress{}
 	weightedMedian := ballot.WeightedMedian()
 	standardDeviation := ballot.StandardDeviation()
-	maxSpread := input.OracleKeeper.RewardBand(input.Ctx).QuoInt64(2)
+	maxSpread := weightedMedian.Mul(input.OracleKeeper.RewardBand(input.Ctx).QuoInt64(2))
 
 	if standardDeviation.GT(maxSpread) {
 		maxSpread = standardDeviation
@@ -301,6 +301,48 @@ func TestOracleRewardDistribution(t *testing.T) {
 	require.Equal(t, expectedRewardAmt, rewards.AmountOf(core.MicroLunaDenom).TruncateInt())
 }
 
+func TestOracleRewardBand(t *testing.T) {
+	input, h := setup(t)
+	params := input.OracleKeeper.GetParams(input.Ctx)
+	params.Whitelist = types.DenomList{core.MicroKRWDenom}
+	input.OracleKeeper.SetParams(input.Ctx, params)
+
+	rewardSpread := randomExchangeRate.Mul(input.OracleKeeper.RewardBand(input.Ctx).QuoInt64(2))
+
+	// no one will miss the vote
+	// Account 1, KRW
+	makePrevoteAndVote(t, input, h, 0, core.MicroKRWDenom, randomExchangeRate.Sub(rewardSpread), 0)
+
+	// Account 2, KRW
+	makePrevoteAndVote(t, input, h, 0, core.MicroKRWDenom, randomExchangeRate, 1)
+
+	// Account 3, KRW
+	makePrevoteAndVote(t, input, h, 0, core.MicroKRWDenom, randomExchangeRate.Add(rewardSpread), 2)
+
+	EndBlocker(input.Ctx, input.OracleKeeper)
+
+	require.Equal(t, int64(0), input.OracleKeeper.GetMissCounter(input.Ctx, keeper.ValAddrs[0]))
+	require.Equal(t, int64(0), input.OracleKeeper.GetMissCounter(input.Ctx, keeper.ValAddrs[1]))
+	require.Equal(t, int64(0), input.OracleKeeper.GetMissCounter(input.Ctx, keeper.ValAddrs[2]))
+
+	// Account 1 will miss the vote due to raward band condition
+	// Account 1, KRW
+	makePrevoteAndVote(t, input, h, 0, core.MicroKRWDenom, randomExchangeRate.Sub(rewardSpread.Add(sdk.OneDec())), 0)
+
+	// Account 2, KRW
+	makePrevoteAndVote(t, input, h, 0, core.MicroKRWDenom, randomExchangeRate, 1)
+
+	// Account 3, KRW
+	makePrevoteAndVote(t, input, h, 0, core.MicroKRWDenom, randomExchangeRate.Add(rewardSpread), 2)
+
+	EndBlocker(input.Ctx, input.OracleKeeper)
+
+	require.Equal(t, int64(1), input.OracleKeeper.GetMissCounter(input.Ctx, keeper.ValAddrs[0]))
+	require.Equal(t, int64(0), input.OracleKeeper.GetMissCounter(input.Ctx, keeper.ValAddrs[1]))
+	require.Equal(t, int64(0), input.OracleKeeper.GetMissCounter(input.Ctx, keeper.ValAddrs[2]))
+
+}
+
 func TestOracleMultiRewardDistribution(t *testing.T) {
 	input, h := setup(t)
 
diff --git a/x/oracle/tally.go b/x/oracle/tally.go
index f9b78a42f..8ee0a882b 100644
--- a/x/oracle/tally.go
+++ b/x/oracle/tally.go
@@ -1,6 +1,7 @@
 package oracle
 
 import (
+	"fmt"
 	"sort"
 
 	sdk "github.com/cosmos/cosmos-sdk/types"
@@ -16,12 +17,14 @@ func tally(ctx sdk.Context, pb types.ExchangeRateBallot, rewardBand sdk.Dec) (we
 
 	weightedMedian = pb.WeightedMedian()
 	standardDeviation := pb.StandardDeviation()
-	rewardSpread := rewardBand.QuoInt64(2)
+	rewardSpread := weightedMedian.Mul(rewardBand.QuoInt64(2))
 
 	if standardDeviation.GT(rewardSpread) {
 		rewardSpread = standardDeviation
 	}
 
+	fmt.Println(standardDeviation)
+
 	for _, vote := range pb {
 		// Filter ballot winners & abstain voters
 		if (vote.ExchangeRate.GTE(weightedMedian.Sub(rewardSpread)) &&

From 702fcf9bd73b156d2b80040a5e6dc02413fbfc61 Mon Sep 17 00:00:00 2001
From: Yun <yun@terra.money>
Date: Wed, 20 Nov 2019 14:52:09 +0900
Subject: [PATCH 2/2] remove print

---
 x/oracle/tally.go | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/x/oracle/tally.go b/x/oracle/tally.go
index 8ee0a882b..b65f22393 100644
--- a/x/oracle/tally.go
+++ b/x/oracle/tally.go
@@ -1,7 +1,6 @@
 package oracle
 
 import (
-	"fmt"
 	"sort"
 
 	sdk "github.com/cosmos/cosmos-sdk/types"
@@ -23,8 +22,6 @@ func tally(ctx sdk.Context, pb types.ExchangeRateBallot, rewardBand sdk.Dec) (we
 		rewardSpread = standardDeviation
 	}
 
-	fmt.Println(standardDeviation)
-
 	for _, vote := range pb {
 		// Filter ballot winners & abstain voters
 		if (vote.ExchangeRate.GTE(weightedMedian.Sub(rewardSpread)) &&