Slashing period unit tests; bugfix

x/slashing/slashing_period.go

@@ -13,11 +13,14 @@ func (k Keeper) capBySlashingPeriod(ctx sdk.Context, address sdk.ValAddress, fra
 	// Calculate total amount to be slashed
 	slashingPeriod := k.getValidatorSlashingPeriodForHeight(ctx, address, infractionHeight)
 	totalToSlash := sdk.MaxDec(slashingPeriod.SlashedSoFar, fraction)
+
+	// Calculate remainder
+	revisedFraction = totalToSlash.Sub(slashingPeriod.SlashedSoFar)
+
+	// Update slashing period
 	slashingPeriod.SlashedSoFar = totalToSlash
 	k.setValidatorSlashingPeriod(ctx, slashingPeriod)
 
-	// Calculate remainder
-	revisedFraction = slashingPeriod.SlashedSoFar.Sub(totalToSlash)
 	return
 
 }

x/slashing/slashing_period_test.go

@@ -0,0 +1,55 @@
+package slashing
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+)
+
+func TestGetSetValidatorSlashingPeriod(t *testing.T) {
+	ctx, _, _, _, keeper := createTestInput(t)
+	addr := sdk.ValAddress(addrs[0])
+	height := int64(5)
+	require.Panics(t, func() { keeper.getValidatorSlashingPeriodForHeight(ctx, addr, height) })
+	newPeriod := ValidatorSlashingPeriod{
+		ValidatorAddr: addr,
+		StartHeight:   height,
+		EndHeight:     height + 10,
+		SlashedSoFar:  sdk.ZeroDec(),
+	}
+	keeper.setValidatorSlashingPeriod(ctx, newPeriod)
+	// Get at start height
+	retrieved := keeper.getValidatorSlashingPeriodForHeight(ctx, addr, height)
+	require.Equal(t, addr, retrieved.ValidatorAddr)
+	// Get before start height
+	retrieved = keeper.getValidatorSlashingPeriodForHeight(ctx, addr, int64(0))
+	require.Equal(t, addr, retrieved.ValidatorAddr)
+	// Get after start height (panic)
+	require.Panics(t, func() { keeper.getValidatorSlashingPeriodForHeight(ctx, addr, int64(6)) })
+	// Get after end height (panic)
+	newPeriod.EndHeight = int64(4)
+	keeper.setValidatorSlashingPeriod(ctx, newPeriod)
+	require.Panics(t, func() { keeper.getValidatorSlashingPeriodForHeight(ctx, addr, height) })
+}
+
+func TestValidatorSlashingPeriodCap(t *testing.T) {
+	ctx, _, _, _, keeper := createTestInput(t)
+	addr := sdk.ValAddress(addrs[0])
+	height := int64(5)
+	newPeriod := ValidatorSlashingPeriod{
+		ValidatorAddr: addr,
+		StartHeight:   height,
+		EndHeight:     height + 10,
+		SlashedSoFar:  sdk.ZeroDec(),
+	}
+	keeper.setValidatorSlashingPeriod(ctx, newPeriod)
+	half := sdk.NewDec(1).Quo(sdk.NewDec(2))
+	// First slash should be full
+	fractionA := keeper.capBySlashingPeriod(ctx, addr, half, height)
+	require.True(t, fractionA.Equal(half))
+	// Second slash should be capped
+	fractionB := keeper.capBySlashingPeriod(ctx, addr, half, height)
+	require.True(t, fractionB.Equal(sdk.ZeroDec()))
+}