Orphan non-accepted blocks before force-committing a slot.

pkg/protocol/block_dispatcher.go

@@ -323,6 +323,7 @@ func (b *BlockDispatcher) processWarpSyncResponse(commitmentID iotago.Commitment
 
 	if len(blockIDs) == 0 {
 		forceCommitmentFunc()
+
 		return nil
 	}
 

pkg/protocol/engine/notarization/slotnotarization/manager.go

@@ -15,6 +15,7 @@ import (
 	"github.com/iotaledger/iota-core/pkg/protocol/engine/blocks"
 	"github.com/iotaledger/iota-core/pkg/protocol/engine/ledger"
 	"github.com/iotaledger/iota-core/pkg/protocol/engine/notarization"
+	"github.com/iotaledger/iota-core/pkg/protocol/engine/tipselection"
 	"github.com/iotaledger/iota-core/pkg/protocol/engine/upgrade"
 	"github.com/iotaledger/iota-core/pkg/protocol/sybilprotection"
 	"github.com/iotaledger/iota-core/pkg/storage"
@@ -34,6 +35,7 @@ type Manager struct {
 	ledger              ledger.Ledger
 	sybilProtection     sybilprotection.SybilProtection
 	upgradeOrchestrator upgrade.Orchestrator
+	tipSelection        tipselection.TipSelection
 
 	storage *storage.Storage
 
@@ -57,6 +59,7 @@ func NewProvider() module.Provider[*engine.Engine, notarization.Notarization] {
 
 			m.ledger = e.Ledger
 			m.sybilProtection = e.SybilProtection
+			m.tipSelection = e.TipSelection
 			m.attestation = e.Attestations
 			m.upgradeOrchestrator = e.UpgradeOrchestrator
 
@@ -111,6 +114,15 @@ func (m *Manager) ForceCommit(slot iotago.SlotIndex) (*model.Commitment, error)
 		return nil, ierrors.New("notarization manager was stopped")
 	}
 
+	// When force committing set acceptance time in TipSelection to the end of the epoch
+	// that is LivenessThresholdUpperBound in the future from the committed slot,
+	// so that all the unaccepted blocks in force committed slot are orphaned.
+	// The value must be at least LivenessThresholdUpperBound in the future.
+	// This is to avoid the situation in which future cone of those blocks becomes accepted after force-committing the slot.
+	// This would cause issues with consistency as it's impossible to add blocks to a committed slot.
+	artificialAcceptanceTime := m.apiProvider.APIForSlot(slot).TimeProvider().SlotEndTime(slot).Add(m.apiProvider.APIForSlot(slot).ProtocolParameters().LivenessThresholdUpperBound())
+	m.tipSelection.SetAcceptanceTime(artificialAcceptanceTime)
+
 	commitment, err := m.createCommitment(slot)
 	if err != nil {
 		return nil, ierrors.Wrapf(err, "failed to create commitment for slot %d", slot)