Most initial interop tests will not have an associated eth1 chain to come to consensus upon via the Eth1Data vote mechanism. This is a quick standard on how clients should stub this vote. The goal here is to check that eth1data updates but to not update it in such a way that new deposits must be processed.
We may come up with a more clever mechanism that can actually handles deposits in the future, but for now we just operate in such a way that disables deposits.
The following stub standard allows the eth1data mechanism to update. This should be used by validators whenever they are supposed to retrieve data from the eth1 chain.
This has validators agreeing upon a stubbed deposit_root and block_hash but always keeps deposit_count at state.eth1_deposit_index so that the consensus does not force deposits even as eth1data is updated.
def get_eth1data_stub(state: BeaconState, current_epoch: Epoch) -> Eth1Data:
epochs_per_period = SLOTS_PER_ETH1_VOTING_PERIOD // SLOTS_PER_EPOCH
voting_period = current_epoch // epochs_per_period
deposit_root = hash(int_to_bytes(voting_period, length=32))
return Eth1Data(
deposit_root=deposit_root,
deposit_count=state.eth1_deposit_index,
block_hash=hash(deposit_root),
)