Merge pull request #72 from terra-project/bugfix/ballot-precision

HOTFIX: ballot tally precision issue breaking CI;

x/oracle/ballot_test.go

@@ -31,6 +31,15 @@ func generateRandomTestCase() (prices []float64, weights []float64) {
 	return
 }
 
+func checkFloatEquality(a sdk.Dec, b float64, precision int) bool {
+	base := math.Pow10(precision)
+
+	a2 := a.MulInt64(int64(base)).TruncateInt64()
+	b2 := int64(b * base)
+
+	return a2 == b2
+}
+
 func TestPBStdDev(t *testing.T) {
 	_, addrs, _, _ := mock.CreateGenAccounts(1, sdk.Coins{})
 
@@ -42,15 +51,9 @@ func TestPBStdDev(t *testing.T) {
 			vote := NewPriceVote(sdk.NewDecWithPrec(int64(price*10000), 4), "", weight, addrs[0])
 			pb = append(pb, vote)
 		}
-
-		precBase := math.Pow10(2)
-		statAnswerRaw := stat.StdDev(prices, weights)
-		statAnswerRounded := float64(int64(statAnswerRaw*precBase)) / precBase
-		ballotAnswerRaw := pb.stdDev()
-		ballotAnswerRounded := float64(ballotAnswerRaw.MulInt64(int64(precBase)).TruncateInt64()) / precBase
-
-		require.Equal(t, statAnswerRounded, ballotAnswerRounded)
-	}
+
+	match := checkFloatEquality(pb.stdDev(), stat.StdDev(prices, weights), 2)
+	require.True(t, match)
 }
 
 func TestPBMean(t *testing.T) {
@@ -65,9 +68,8 @@ func TestPBMean(t *testing.T) {
 		pb = append(pb, vote)
 	}
 
-	statAnswerRounded := float64(int64(stat.Mean(prices, weights)*10000)) / 10000
-	ballotAnswerRounded := float64(pb.mean().Mul(sdk.NewDec(10000)).TruncateInt64()) / 10000
-	require.Equal(t, ballotAnswerRounded, statAnswerRounded)
+	match := checkFloatEquality(pb.mean(), stat.Mean(prices, weights), 2)
+	require.True(t, match)
 }
 
 func TestPBWeightedMedian(t *testing.T) {