test(fc): finalization prunes stale aggregated payloads from store

tests/consensus/devnet/fc/test_store_pruning.py

@@ -0,0 +1,225 @@
+"""Fork Choice: Finalization prunes stale aggregated payloads."""
+
+import pytest
+from consensus_testing import (
+    AggregatedAttestationSpec,
+    AttestationCheck,
+    BlockSpec,
+    BlockStep,
+    ForkChoiceTestFiller,
+    GossipAggregatedAttestationSpec,
+    GossipAggregatedAttestationStep,
+    StoreChecks,
+    TickStep,
+)
+
+from lean_spec.subspecs.containers.slot import Slot
+from lean_spec.subspecs.containers.validator import ValidatorIndex
+
+pytestmark = pytest.mark.valid_until("Devnet")
+
+
+def test_finalization_prunes_stale_aggregated_payloads(
+    fork_choice_test: ForkChoiceTestFiller,
+) -> None:
+    """
+    Aggregated attestation payloads targeting finalized slots are pruned.
+
+    Scenario
+    --------
+    Four validators. Linear chain through slot 6.
+
+    Phase 1 -- Build chain and achieve first finalization (finalized=1)::
+
+        genesis(0) -> block_1(1) -> block_2(2) -> block_3(3) -> block_4(4) -> block_5(5)
+
+    - block_3 carries supermajority (V0,V1,V2) justifying slot 1
+    - block_5 carries supermajority (V0,V1,V2) justifying slot 2
+    - Justifying slot 2 with source=1 finalizes slot 1
+
+    Phase 2 -- Fire the aggregate interval, then submit gossip:
+
+    - TickStep to time=22 advances to slot 5 interval 2 (aggregate interval).
+      The pool is still empty so aggregate does nothing.
+    - Stale: validators {0,1,2}, target=1 (at finalized slot)
+    - Fresh: validators {1,2,3}, target=5 (above finalized slot)
+
+    Both land in latest_new_aggregated_payloads at interval 27.
+
+    Phase 3 -- Advance finalization to trigger pruning:
+
+    - block_6 carries supermajority (V0,V1,V2) justifying slot 3
+    - Justifying slot 3 with source=2 finalizes slot 2
+    - BlockStep auto-ticks from interval 27 to interval 30 (slot 6 start),
+      passing through slot 5 interval 4 which calls accept_new_attestations()
+      -- gossip migrates from "new" to "known"
+    - prune_stale_attestation_data removes entries where target <= finalized=2
+    - Stale (target=1): pruned
+    - Fresh (target=5): kept
+    """
+    fork_choice_test(
+        steps=[
+            # Phase 1: Build chain and achieve finalized=1, justified=2
+            BlockStep(
+                block=BlockSpec(slot=Slot(1), label="block_1"),
+                checks=StoreChecks(head_slot=Slot(1)),
+            ),
+            BlockStep(
+                block=BlockSpec(slot=Slot(2), label="block_2"),
+                checks=StoreChecks(head_slot=Slot(2)),
+            ),
+            # Justify slot 1: supermajority (3/4) with source=genesis/0, target=block_1/1
+            BlockStep(
+                block=BlockSpec(
+                    slot=Slot(3),
+                    label="block_3",
+                    attestations=[
+                        AggregatedAttestationSpec(
+                            validator_ids=[
+                                ValidatorIndex(0),
+                                ValidatorIndex(1),
+                                ValidatorIndex(2),
+                            ],
+                            slot=Slot(3),
+                            target_slot=Slot(1),
+                            target_root_label="block_1",
+                        ),
+                    ],
+                ),
+                checks=StoreChecks(
+                    head_slot=Slot(3),
+                    latest_justified_slot=Slot(1),
+                    latest_finalized_slot=Slot(0),
+                ),
+            ),
+            BlockStep(
+                block=BlockSpec(slot=Slot(4), label="block_4"),
+                checks=StoreChecks(head_slot=Slot(4)),
+            ),
+            # Justify slot 2: supermajority (3/4) with source=block_1/1, target=block_2/2
+            # Finalization: range(1+1, 2) = [] -> finalizes slot 1
+            BlockStep(
+                block=BlockSpec(
+                    slot=Slot(5),
+                    label="block_5",
+                    attestations=[
+                        AggregatedAttestationSpec(
+                            validator_ids=[
+                                ValidatorIndex(0),
+                                ValidatorIndex(1),
+                                ValidatorIndex(2),
+                            ],
+                            slot=Slot(5),
+                            target_slot=Slot(2),
+                            target_root_label="block_2",
+                        ),
+                    ],
+                ),
+                checks=StoreChecks(
+                    head_slot=Slot(5),
+                    latest_justified_slot=Slot(2),
+                    latest_finalized_slot=Slot(1),
+                ),
+            ),
+            # Phase 2: Fire aggregate interval on empty pool, then submit gossip
+            #
+            # aggregate() at interval 2 discards lone child proofs from "new".
+            # Gossip must be submitted AFTER the aggregate interval so that
+            # the subsequent acceptance interval (slot 5, interval 4) can
+            # migrate them from "new" to "known" during the block_6 tick.
+            #
+            # time=22 => floor(22000/800) = interval 27 = slot 5, interval 2.
+            # Pool is empty at this point so aggregate is a no-op.
+            TickStep(time=22),
+            # Store time is now interval 27 (slot 5, interval 2).
+            # Both attestations go into latest_new_aggregated_payloads.
+            #
+            # Stale gossip: target=1 (at finalized slot), should be pruned later
+            GossipAggregatedAttestationStep(
+                attestation=GossipAggregatedAttestationSpec(
+                    validator_ids=[
+                        ValidatorIndex(0),
+                        ValidatorIndex(1),
+                        ValidatorIndex(2),
+                    ],
+                    slot=Slot(5),
+                    target_slot=Slot(1),
+                    target_root_label="block_1",
+                    source_slot=Slot(0),
+                    source_root_label="genesis",
+                ),
+            ),
+            # Fresh gossip: target=5 (above finalized), should survive pruning
+            # V3 is unique to this attestation (not in stale)
+            GossipAggregatedAttestationStep(
+                attestation=GossipAggregatedAttestationSpec(
+                    validator_ids=[
+                        ValidatorIndex(1),
+                        ValidatorIndex(2),
+                        ValidatorIndex(3),
+                    ],
+                    slot=Slot(5),
+                    target_slot=Slot(5),
+                    target_root_label="block_5",
+                    source_slot=Slot(2),
+                    source_root_label="block_2",
+                ),
+                checks=StoreChecks(
+                    attestation_checks=[
+                        AttestationCheck(
+                            validator=ValidatorIndex(0),
+                            location="new",
+                            target_slot=Slot(1),
+                        ),
+                        AttestationCheck(
+                            validator=ValidatorIndex(3),
+                            location="new",
+                            target_slot=Slot(5),
+                        ),
+                    ],
+                ),
+            ),
+            # Phase 3: Advance finalization to trigger pruning
+            #
+            # block_6 carries supermajority (V0,V1,V2) justifying slot 3
+            # Source auto-resolves to parent state's justified = (block_2, slot 2)
+            #
+            # BlockStep auto-ticks from interval 27 to interval 30 (slot 6 start),
+            # passing through interval 29 (slot 5, interval 4) which calls
+            # accept_new_attestations() -- gossip migrates from "new" to "known"
+            #
+            # on_block processes block_6:
+            # - In-block attestation justifies slot 3, source=2 -> finalizes slot 2
+            # - prune_stale_attestation_data is called
+            # - Stale (target=1 <= finalized=2): REMOVED
+            # - Fresh (target=5 > finalized=2): KEPT in "known"
+            BlockStep(
+                block=BlockSpec(
+                    slot=Slot(6),
+                    label="block_6",
+                    attestations=[
+                        AggregatedAttestationSpec(
+                            validator_ids=[
+                                ValidatorIndex(0),
+                                ValidatorIndex(1),
+                                ValidatorIndex(2),
+                            ],
+                            slot=Slot(6),
+                            target_slot=Slot(3),
+                            target_root_label="block_3",
+                        ),
+                    ],
+                ),
+                checks=StoreChecks(
+                    latest_finalized_slot=Slot(2),
+                    attestation_checks=[
+                        AttestationCheck(
+                            validator=ValidatorIndex(3),
+                            location="known",
+                            target_slot=Slot(5),
+                        ),
+                    ],
+                ),
+            ),
+        ],
+    )