def METHOD_NAME(spec, state):
    genesis_block, store = setup_test(spec, state)
    # Forward to next sync committee period
    next_slots(spec, state, spec.UPDATE_TIMEOUT)
    store_period = spec.compute_sync_committee_period_at_slot(store.optimistic_header.beacon.slot)
    update_period = spec.compute_sync_committee_period_at_slot(state.slot)
    assert store_period + 1 == update_period
    attested_block = state_transition_with_full_block(spec, state, False, False)
    signature_slot = state.slot + 1
    update = create_update(
        spec,
        attested_state=state,
        attested_block=attested_block,
        finalized_block=genesis_block,
        with_next=True,
        with_finality=False,
        participation_rate=1.0,
    )
    pre_store = deepcopy(store)
    spec.process_light_client_update(store, update, signature_slot, state.genesis_validators_root)
    assert store.finalized_header == pre_store.finalized_header
    assert store.best_valid_update == update
    assert store.optimistic_header == update.attested_header
    assert store.current_max_active_participants > 0