| 153 | |
| 154 | |
| 155 | def build_attestation_data(state, slot, shard): |
| 156 | assert state.slot >= slot |
| 157 | |
| 158 | block_root = construct_empty_block_for_next_slot(state).previous_block_root |
| 159 | |
| 160 | epoch_start_slot = get_epoch_start_slot(get_current_epoch(state)) |
| 161 | if epoch_start_slot == slot: |
| 162 | epoch_boundary_root = block_root |
| 163 | else: |
| 164 | get_block_root(state, epoch_start_slot) |
| 165 | |
| 166 | if slot < epoch_start_slot: |
| 167 | justified_block_root = state.previous_justified_root |
| 168 | else: |
| 169 | justified_block_root = state.current_justified_root |
| 170 | |
| 171 | return AttestationData( |
| 172 | slot=slot, |
| 173 | shard=shard, |
| 174 | beacon_block_root=block_root, |
| 175 | source_epoch=state.current_justified_epoch, |
| 176 | source_root=justified_block_root, |
| 177 | target_root=epoch_boundary_root, |
| 178 | crosslink_data_root=spec.ZERO_HASH, |
| 179 | previous_crosslink=deepcopy(state.latest_crosslinks[shard]), |
| 180 | ) |
| 181 | |
| 182 | |
| 183 | # @timeit |