Implement ValidatorSet.Slash

x/slashing/keeper.go

@@ -72,7 +72,6 @@ func (k Keeper) handleDoubleSign(ctx sdk.Context, height int64, timestamp int64,
 	}
 	logger.Info(fmt.Sprintf("Confirmed double sign from %v at height %d, age of %d less than max age of %d", pubkey.Address(), height, age, MaxEvidenceAge))
 	k.stakeKeeper.Slash(ctx, pubkey, height, SlashFractionDoubleSign)
-	logger.Info(fmt.Sprintf("Slashed validator %s by fraction %v for double-sign at height %d", pubkey.Address(), SlashFractionDoubleSign, height))
 }
 
 // handle a validator signature, must be called once per validator per block
@@ -99,8 +98,6 @@ func (k Keeper) handleValidatorSignature(ctx sdk.Context, pubkey crypto.PubKey,
 	if height > minHeight && signInfo.SignedBlocksCounter < MinSignedPerWindow {
 		k.stakeKeeper.Slash(ctx, pubkey, height, SlashFractionDowntime)
 		k.stakeKeeper.ForceUnbond(ctx, pubkey, DowntimeUnbondDuration)
-		logger.Info(fmt.Sprintf("Slashed validator %s by fraction %v and unbonded for downtime at height %d, cannot rebond for %ds",
-			address, SlashFractionDowntime, height, DowntimeUnbondDuration))
 	}
 }
 

x/slashing/keeper_test.go

@@ -2,6 +2,7 @@ package slashing
 
 import (
 	"encoding/hex"
+	"os"
 	"testing"
 
 	"github.com/stretchr/testify/require"
@@ -52,7 +53,7 @@ func createTestInput(t *testing.T) (sdk.Context, bank.Keeper, stake.Keeper, Keep
 	ms.MountStoreWithDB(keySlashing, sdk.StoreTypeIAVL, db)
 	err := ms.LoadLatestVersion()
 	require.Nil(t, err)
-	ctx := sdk.NewContext(ms, abci.Header{}, false, nil, log.NewNopLogger(), nil)
+	ctx := sdk.NewContext(ms, abci.Header{}, false, nil, log.NewTMLogger(os.Stdout), nil)
 	cdc := createTestCodec()
 	accountMapper := auth.NewAccountMapper(cdc, keyAcc, &auth.BaseAccount{})
 	ck := bank.NewKeeper(accountMapper)
@@ -74,8 +75,9 @@ func TestHandleDoubleSign(t *testing.T) {
 	require.True(t, got.IsOK())
 	_ = sk.Tick(ctx)
 	require.Equal(t, ck.GetCoins(ctx, addr), sdk.Coins{{sk.GetParams(ctx).BondDenom, initCoins - amt}})
+	require.Equal(t, sdk.NewRat(amt), sk.Validator(ctx, addr).GetPower())
 	keeper.handleDoubleSign(ctx, 0, 0, val)
-	// TODO
+	require.Equal(t, sdk.NewRat(amt).Mul(sdk.NewRat(19).Quo(sdk.NewRat(20))), sk.Validator(ctx, addr).GetPower())
 }
 
 func TestHandleAbsentValidator(t *testing.T) {

x/stake/keeper.go

@@ -779,8 +779,28 @@ func (k Keeper) IterateDelegators(ctx sdk.Context, delAddr sdk.Address, fn func(
 
 // slash a validator
 func (k Keeper) Slash(ctx sdk.Context, pubkey crypto.PubKey, height int64, fraction sdk.Rat) {
+	// TODO height ignored for now, see https://github.com/cosmos/cosmos-sdk/pull/1011#issuecomment-390253957
+	val, found := k.GetValidatorByPubKey(ctx, pubkey)
+	if !found {
+		panic(fmt.Errorf("Attempted to slash a nonexistent validator with pubkey %s", pubkey))
+	}
+	sharesToRemove := val.PoolShares.Amount.Mul(fraction)
+	pool := k.GetPool(ctx)
+	val, pool, burned := val.removePoolShares(pool, sharesToRemove)
+	k.setPool(ctx, pool)        // update the pool
+	k.updateValidator(ctx, val) // update the validator, possibly kicking it out
+	ctx.Logger().With("module", "x/stake").Info(fmt.Sprintf("Validator %v slashed by fraction %v, removed %v shares and burned %d tokens", pubkey, fraction, sharesToRemove, burned))
+	return
 }
 
 // force unbond a validator
 func (k Keeper) ForceUnbond(ctx sdk.Context, pubkey crypto.PubKey, jailDuration int64) {
+	// TODO Implement
+	/*
+		val, found := k.GetValidatorByPubKey(ctx, pubkey)
+		if !found {
+			ctx.Logger().Info("Validator with pubkey %s not found, cannot force unbond", pubkey)
+			return
+		}
+	*/
 }

x/stake/validator.go

@@ -153,6 +153,21 @@ func (v Validator) UpdateStatus(pool Pool, NewStatus sdk.BondStatus) (Validator,
 	return v, pool
 }
 
+// Remove & burn pool shares, e.g. when slashing a validator
+func (v Validator) removePoolShares(pool Pool, amt sdk.Rat) (Validator, Pool, int64) {
+	var tokens int64
+	switch v.Status() {
+	case sdk.Unbonded:
+		pool, tokens = pool.removeSharesUnbonded(amt)
+	case sdk.Unbonding:
+		pool, tokens = pool.removeSharesUnbonding(amt)
+	case sdk.Bonded:
+		pool, tokens = pool.removeSharesBonded(amt)
+	}
+	v.PoolShares.Amount = v.PoolShares.Amount.Sub(amt)
+	return v, pool, tokens
+}
+
 // XXX TEST
 // get the power or potential power for a validator
 // if bonded, the power is the BondedShares