feat: add coins burned to slash event

x/distribution/types/expected_keepers.go

@@ -47,7 +47,7 @@ type StakingKeeper interface {
 	ValidatorByConsAddr(sdk.Context, sdk.ConsAddress) stakingtypes.ValidatorI // get a particular validator by consensus address
 
 	// slash the validator and delegators of the validator, specifying offence height, offence power, and slash fraction
-	Slash(sdk.Context, sdk.ConsAddress, int64, int64, sdk.Dec)
+	Slash(sdk.Context, sdk.ConsAddress, int64, int64, sdk.Dec) sdk.Int
 	Jail(sdk.Context, sdk.ConsAddress)   // jail a validator
 	Unjail(sdk.Context, sdk.ConsAddress) // unjail a validator
 

x/slashing/keeper/infractions.go

@@ -84,16 +84,17 @@ func (k Keeper) HandleValidatorSignature(ctx sdk.Context, addr cryptotypes.Addre
 			// That's fine since this is just used to filter unbonding delegations & redelegations.
 			distributionHeight := height - sdk.ValidatorUpdateDelay - 1
 
+			coinsBurned := k.sk.Slash(ctx, consAddr, distributionHeight, power, k.SlashFractionDowntime(ctx))
 			ctx.EventManager().EmitEvent(
 				sdk.NewEvent(
 					types.EventTypeSlash,
 					sdk.NewAttribute(types.AttributeKeyAddress, consAddr.String()),
 					sdk.NewAttribute(types.AttributeKeyPower, fmt.Sprintf("%d", power)),
 					sdk.NewAttribute(types.AttributeKeyReason, types.AttributeValueMissingSignature),
 					sdk.NewAttribute(types.AttributeKeyJailed, consAddr.String()),
+					sdk.NewAttribute(types.AttributeKeyBurnedCoins, coinsBurned.String()),
 				),
 			)
-			k.sk.Slash(ctx, consAddr, distributionHeight, power, k.SlashFractionDowntime(ctx))
 			k.sk.Jail(ctx, consAddr)
 
 			signInfo.JailedUntil = ctx.BlockHeader().Time.Add(k.DowntimeJailDuration(ctx))

x/slashing/keeper/keeper.go

@@ -65,29 +65,28 @@ func (k Keeper) GetPubkey(ctx sdk.Context, a cryptotypes.Address) (cryptotypes.P
 // Slash attempts to slash a validator. The slash is delegated to the staking
 // module to make the necessary validator changes.
 func (k Keeper) Slash(ctx sdk.Context, consAddr sdk.ConsAddress, fraction sdk.Dec, power, distributionHeight int64) {
+	coinsBurned := k.sk.Slash(ctx, consAddr, distributionHeight, power, fraction)
 	ctx.EventManager().EmitEvent(
 		sdk.NewEvent(
 			types.EventTypeSlash,
 			sdk.NewAttribute(types.AttributeKeyAddress, consAddr.String()),
 			sdk.NewAttribute(types.AttributeKeyPower, fmt.Sprintf("%d", power)),
 			sdk.NewAttribute(types.AttributeKeyReason, types.AttributeValueDoubleSign),
+			sdk.NewAttribute(types.AttributeKeyBurnedCoins, coinsBurned.String()),
 		),
 	)
-
-	k.sk.Slash(ctx, consAddr, distributionHeight, power, fraction)
 }
 
 // Jail attempts to jail a validator. The slash is delegated to the staking module
 // to make the necessary validator changes.
 func (k Keeper) Jail(ctx sdk.Context, consAddr sdk.ConsAddress) {
+	k.sk.Jail(ctx, consAddr)
 	ctx.EventManager().EmitEvent(
 		sdk.NewEvent(
 			types.EventTypeSlash,
 			sdk.NewAttribute(types.AttributeKeyJailed, consAddr.String()),
 		),
 	)
-
-	k.sk.Jail(ctx, consAddr)
 }
 
 func (k Keeper) deleteAddrPubkeyRelation(ctx sdk.Context, addr cryptotypes.Address) {

x/slashing/spec/06_events.md

@@ -25,6 +25,7 @@ The slashing module emits the following events/tags:
 | slash | power         | {validatorPower}            |
 | slash | reason        | {slashReason}               |
 | slash | jailed [0]    | {validatorConsensusAddress} |
+| slash | burned coins  | {sdk.Int}                   |
 
 - [0] Only included if the validator is jailed.
 

x/slashing/types/events.go

@@ -11,6 +11,7 @@ const (
 	AttributeKeyReason       = "reason"
 	AttributeKeyJailed       = "jailed"
 	AttributeKeyMissedBlocks = "missed_blocks"
+	AttributeKeyBurnedCoins  = "burned_coins"
 
 	AttributeValueDoubleSign       = "double_sign"
 	AttributeValueMissingSignature = "missing_signature"

x/slashing/types/expected_keepers.go

@@ -42,7 +42,7 @@ type StakingKeeper interface {
 	ValidatorByConsAddr(sdk.Context, sdk.ConsAddress) stakingtypes.ValidatorI // get a particular validator by consensus address
 
 	// slash the validator and delegators of the validator, specifying offence height, offence power, and slash fraction
-	Slash(sdk.Context, sdk.ConsAddress, int64, int64, sdk.Dec)
+	Slash(sdk.Context, sdk.ConsAddress, int64, int64, sdk.Dec) sdk.Int
 	Jail(sdk.Context, sdk.ConsAddress)   // jail a validator
 	Unjail(sdk.Context, sdk.ConsAddress) // unjail a validator
 

x/staking/keeper/slash.go

@@ -21,7 +21,7 @@ import (
 // CONTRACT:
 //    Infraction was committed at the current height or at a past height,
 //    not at a height in the future
-func (k Keeper) Slash(ctx sdk.Context, consAddr sdk.ConsAddress, infractionHeight int64, power int64, slashFactor sdk.Dec) {
+func (k Keeper) Slash(ctx sdk.Context, consAddr sdk.ConsAddress, infractionHeight int64, power int64, slashFactor sdk.Dec) sdk.Int {
 	logger := k.Logger(ctx)
 
 	if slashFactor.IsNegative() {
@@ -45,7 +45,7 @@ func (k Keeper) Slash(ctx sdk.Context, consAddr sdk.ConsAddress, infractionHeigh
 			"WARNING: ignored attempt to slash a nonexistent validator; we recommend you investigate immediately",
 			"validator", consAddr.String(),
 		)
-		return
+		return sdk.NewInt(0)
 	}
 
 	// should not be slashing an unbonded validator
@@ -140,6 +140,7 @@ func (k Keeper) Slash(ctx sdk.Context, consAddr sdk.ConsAddress, infractionHeigh
 		"slash_factor", slashFactor.String(),
 		"burned", tokensToBurn,
 	)
+	return tokensToBurn
 }
 
 // jail a validator

x/staking/keeper/slash_test.go

@@ -604,3 +604,16 @@ func TestSlashBoth(t *testing.T) {
 	// power not decreased, all stake was bonded since
 	require.Equal(t, int64(10), validator.GetConsensusPower(app.StakingKeeper.PowerReduction(ctx)))
 }
+
+func TestSlashAmount(t *testing.T) {
+	app, ctx, _, _ := bootstrapSlashTest(t, 10)
+	consAddr := sdk.ConsAddress(PKs[0].Address())
+	fraction := sdk.NewDecWithPrec(5, 1)
+	burnedCoins := app.StakingKeeper.Slash(ctx, consAddr, ctx.BlockHeight(), 10, fraction)
+	require.True(t, burnedCoins.GT(sdk.ZeroInt()))
+
+	// test the case where the validator was not found, which should return no coins
+	_, addrVals := generateAddresses(app, ctx, 100)
+	noBurned := app.StakingKeeper.Slash(ctx, sdk.ConsAddress(addrVals[0]), ctx.BlockHeight(), 10, fraction)
+	require.True(t, sdk.NewInt(0).Equal(noBurned))
+}

x/staking/types/expected_keepers.go

@@ -59,7 +59,7 @@ type ValidatorSet interface {
 	StakingTokenSupply(sdk.Context) sdk.Int                      // total staking token supply
 
 	// slash the validator and delegators of the validator, specifying offence height, offence power, and slash fraction
-	Slash(sdk.Context, sdk.ConsAddress, int64, int64, sdk.Dec)
+	Slash(sdk.Context, sdk.ConsAddress, int64, int64, sdk.Dec) sdk.Int
 	Jail(sdk.Context, sdk.ConsAddress)   // jail a validator
 	Unjail(sdk.Context, sdk.ConsAddress) // unjail a validator