feat(slashing): add singularity height getter (#20)

Author: 0xHansLee

x/slashing/keeper/infractions.go

@@ -109,13 +109,13 @@ func (k Keeper) HandleValidatorSignature(ctx context.Context, addr cryptotypes.A
 	minHeight := signInfo.StartHeight + signedBlocksWindow
 	maxMissed := signedBlocksWindow - minSignedPerWindow
 
-	params, err := k.GetParams(ctx)
+	singularityHeight, err := k.SingularityHeight(ctx)
 	if err != nil {
 		return errors.Wrap(err, "failed to get params")
 	}
 
 	// if we are past the minimum height and the validator has missed too many blocks, punish them
-	if height > int64(params.SingularityHeight) && height > minHeight && signInfo.MissedBlocksCounter > maxMissed {
+	if height > int64(singularityHeight) && height > minHeight && signInfo.MissedBlocksCounter > maxMissed {
 		validator, err := k.sk.ValidatorByConsAddr(ctx, consAddr)
 		if err != nil {
 			return err
@@ -175,7 +175,7 @@ func (k Keeper) HandleValidatorSignature(ctx context.Context, addr cryptotypes.A
 				"slashed", slashFractionDowntime.String(),
 				"jailed_until", signInfo.JailedUntil,
 			)
-		} else if height == int64(params.SingularityHeight) {
+		} else if height == int64(singularityHeight) {
 			// reset the counter & bitmap so that the validator won't be
 			// immediately slashed after singularity.
 			signInfo.MissedBlocksCounter = 0

x/slashing/keeper/params.go

@@ -48,6 +48,11 @@ func (k Keeper) SlashFractionDowntime(ctx context.Context) (sdkmath.LegacyDec, e
 	return params.SlashFractionDowntime, err
 }
 
+func (k Keeper) SingularityHeight(ctx context.Context) (uint64, error) {
+	params, err := k.GetParams(ctx)
+	return params.SingularityHeight, err
+}
+
 // GetParams returns the current x/slashing module parameters.
 func (k Keeper) GetParams(ctx context.Context) (params types.Params, err error) {
 	store := k.storeService.OpenKVStore(ctx)