From 04200ffbb38ced04269c21cdaa3e1a8f68aed9a1 Mon Sep 17 00:00:00 2001
From: Etan Kissling <etan@status.im>
Date: Mon, 28 Feb 2022 13:20:42 +0100
Subject: [PATCH] use next slot when signing for light client tests

In practice, the sync committee signs `LightClientUpdate` instances at
the next slot following the block. This is not correctly reflected in
the tests, where it is signed one slot early. This patch updates the
tests to use the correct slot for the computation.
---
 .../altair/test_fixture_sync_protocol.nim      | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/tests/consensus_spec/altair/test_fixture_sync_protocol.nim b/tests/consensus_spec/altair/test_fixture_sync_protocol.nim
index 50d22e2e09..05d30c7629 100644
--- a/tests/consensus_spec/altair/test_fixture_sync_protocol.nim
+++ b/tests/consensus_spec/altair/test_fixture_sync_protocol.nim
@@ -25,6 +25,7 @@ import
 # https://github.com/ethereum/consensus-specs/blob/v1.1.9/tests/core/pyspec/eth2spec/test/helpers/sync_committee.py#L27-L44
 proc compute_aggregate_sync_committee_signature(
     forked: ForkedHashedBeaconState,
+    signature_slot: Slot,
     participants: openArray[ValidatorIndex],
     block_root: Eth2Digest): ValidatorSig =
   template state: untyped {.inject.} = forked.altairData.data
@@ -41,7 +42,7 @@ proc compute_aggregate_sync_committee_signature(
       signature = get_sync_committee_message_signature(
         state.fork,
         state.genesis_validators_root,
-        state.slot,
+        signature_slot,
         block_root,
         privkey)
     if not initialized:
@@ -107,12 +108,13 @@ suite "EF - Altair - Unittests - Sync protocol" & preset():
       block_header = signed_block.toBeaconBlockHeader
 
     # Sync committee signing the block_header
+      signature_slot = block_header.slot + 1
       all_pubkeys = state.validators.mapIt(it.pubkey)
       committee = state.current_sync_committee.pubkeys
         .mapIt(all_pubkeys.find(it).ValidatorIndex)
       sync_committee_bits = full_sync_committee_bits
       sync_committee_signature = compute_aggregate_sync_committee_signature(
-        forked[], committee, block_header.hash_tree_root())
+        forked[], signature_slot, committee, block_header.hash_tree_root())
       sync_aggregate = SyncAggregate(
         sync_committee_bits: sync_committee_bits,
         sync_committee_signature: sync_committee_signature)
@@ -140,7 +142,7 @@ suite "EF - Altair - Unittests - Sync protocol" & preset():
         sync_aggregate: sync_aggregate,
         fork_version: state.fork.current_version)
       res = process_light_client_update(
-        store, update, state.slot, state.genesis_validators_root)
+        store, update, signature_slot, state.genesis_validators_root)
 
     check:
       res
@@ -171,12 +173,13 @@ suite "EF - Altair - Unittests - Sync protocol" & preset():
       block_header = signed_block.toBeaconBlockHeader
 
     # Sync committee signing the block_header
+      signature_slot = block_header.slot + 1
       all_pubkeys = state.validators.mapIt(it.pubkey)
       committee = state.current_sync_committee.pubkeys
         .mapIt(all_pubkeys.find(it).ValidatorIndex)
       sync_committee_bits = full_sync_committee_bits
       sync_committee_signature = compute_aggregate_sync_committee_signature(
-        forked[], committee, block_header.hash_tree_root())
+        forked[], signature_slot, committee, block_header.hash_tree_root())
       sync_aggregate = SyncAggregate(
         sync_committee_bits: sync_committee_bits,
         sync_committee_signature: sync_committee_signature)
@@ -203,7 +206,7 @@ suite "EF - Altair - Unittests - Sync protocol" & preset():
         sync_aggregate: sync_aggregate,
         fork_version: state.fork.current_version)
       res = process_light_client_update(
-        store, update, state.slot, state.genesis_validators_root)
+        store, update, signature_slot, state.genesis_validators_root)
 
     check:
       res
@@ -274,12 +277,13 @@ suite "EF - Altair - Unittests - Sync protocol" & preset():
         body_root: blck.body.hash_tree_root())
 
     # Sync committee signing the finalized_block_header
+      signature_slot = block_header.slot + 1
       all_pubkeys = state.validators.mapIt(it.pubkey)
       committee = state.current_sync_committee.pubkeys
         .mapIt(all_pubkeys.find(it).ValidatorIndex)
       sync_committee_bits = full_sync_committee_bits
       sync_committee_signature = compute_aggregate_sync_committee_signature(
-        forked[], committee, block_header.hash_tree_root())
+        forked[], signature_slot, committee, block_header.hash_tree_root())
       sync_aggregate = SyncAggregate(
         sync_committee_bits: sync_committee_bits,
         sync_committee_signature: sync_committee_signature)
@@ -293,7 +297,7 @@ suite "EF - Altair - Unittests - Sync protocol" & preset():
         sync_aggregate: sync_aggregate,
         fork_version: state.fork.current_version)
       res = process_light_client_update(
-        store, update, state.slot, state.genesis_validators_root)
+        store, update, signature_slot, state.genesis_validators_root)
 
     check:
       res