diff --git a/specs/phase1/shard-fork-choice.md b/specs/phase1/shard-fork-choice.md index 844dbfb86..b1fc3080e 100644 --- a/specs/phase1/shard-fork-choice.md +++ b/specs/phase1/shard-fork-choice.md @@ -46,7 +46,7 @@ class ShardStore: def get_forkchoice_shard_store(anchor_state: BeaconState, shard: Shard) -> ShardStore: return ShardStore( shard=shard, - blocks={anchor_state.shard_states[shard].latest_block_root: ShardBlock(slot=anchor_state.slot)}, + blocks={anchor_state.shard_states[shard].latest_block_root: ShardBlock(slot=anchor_state.slot, shard=shard)}, block_states={anchor_state.shard_states[shard].latest_block_root: anchor_state.copy().shard_states[shard]}, ) ``` @@ -168,13 +168,15 @@ def on_shard_block(store: Store, shard_store: ShardStore, signed_shard_block: Si get_ancestor(store, shard_block.beacon_parent_root, finalized_slot) == store.finalized_checkpoint.root ) - # Add new block to the store - shard_store.blocks[hash_tree_root(shard_block)] = shard_block - # Check the block is valid and compute the post-state assert verify_shard_block_message(beacon_parent_state, shard_parent_state, shard_block, shard_block.slot, shard) assert verify_shard_block_signature(beacon_parent_state, signed_shard_block) + post_state = get_post_shard_state(beacon_parent_state, shard_parent_state, shard_block) + + # Add new block to the store + shard_store.blocks[hash_tree_root(shard_block)] = shard_block + # Add new state for this block to the store shard_store.block_states[hash_tree_root(shard_block)] = post_state ``` diff --git a/specs/phase1/shard-transition.md b/specs/phase1/shard-transition.md index 191dbd1aa..fe3223933 100644 --- a/specs/phase1/shard-transition.md +++ b/specs/phase1/shard-transition.md @@ -47,20 +47,14 @@ def verify_shard_block_message(beacon_state: BeaconState, shard_parent_state: ShardState, block: ShardBlock, slot: Slot, - shard: Shard, - beacon_parent_slot: Slot=None) -> bool: + shard: Shard) -> bool: # Check `shard_parent_root` field assert block.shard_parent_root == shard_parent_state.latest_block_root # Check `beacon_parent_root` field - if beacon_parent_slot is None: - beacon_parent_slot = beacon_state.slot - if beacon_parent_slot == beacon_state.slot: - beacon_parent_block_header = beacon_state.latest_block_header.copy() - if beacon_parent_block_header.state_root == Root(): - beacon_parent_block_header.state_root = hash_tree_root(beacon_state) - beacon_parent_root = hash_tree_root(beacon_parent_block_header) - else: - beacon_parent_root = get_block_root_at_slot(beacon_state, beacon_parent_slot) + beacon_parent_block_header = beacon_state.latest_block_header.copy() + if beacon_parent_block_header.state_root == Root(): + beacon_parent_block_header.state_root = hash_tree_root(beacon_state) + beacon_parent_root = hash_tree_root(beacon_parent_block_header) assert block.beacon_parent_root == beacon_parent_root # Check `slot` field next_slot = Slot(slot + 1) @@ -191,26 +185,6 @@ def compute_shard_body_roots(proposals: Sequence[SignedShardBlock]) -> Sequence[ return [hash_tree_root(proposal.message.body) for proposal in proposals] ``` -```python -def get_proposal_choices_at_slot(beacon_state: BeaconState, - shard_parent_state: ShardState, - slot: Slot, - shard: Shard, - shard_blocks: Sequence[SignedShardBlock], - validate_signature: bool=True) -> Sequence[SignedShardBlock]: - """ - Return the valid shard blocks at the given ``slot``. - Note that this function doesn't change the state. - """ - choices = [] - shard_blocks_at_slot = [block for block in shard_blocks if block.message.slot == slot] - shard_state = shard_parent_state.copy() - for block in shard_blocks_at_slot: - shard_state = get_post_shard_state(beacon_state, shard_state, block.message) - choices.append(block) - return choices -``` - ```python def get_proposal_at_slot(beacon_state: BeaconState, shard_parent_state: ShardState, @@ -222,21 +196,14 @@ def get_proposal_at_slot(beacon_state: BeaconState, Return ``proposal``, ``shard_state`` of the given ``slot``. Note that this function doesn't change the state. """ - choices = get_proposal_choices_at_slot( - beacon_state=beacon_state, - shard_parent_state=shard_parent_state, - slot=slot, - shard=shard, - shard_blocks=shard_blocks, - validate_signature=validate_signature, - ) - if len(choices) == 0: + shard_blocks = [block for block in shard_blocks if block.message.slot == slot] + if len(shard_blocks) == 0: block = ShardBlock(slot=slot, shard=shard) proposal = SignedShardBlock(message=block) - elif len(choices) == 1: - proposal = choices[0] + elif len(shard_blocks) == 1: + proposal = shard_blocks[0] else: - proposal = get_winning_proposal(beacon_state, choices) + proposal = get_winning_proposal(beacon_state, shard_blocks) # Apply state transition shard_state = get_post_shard_state(beacon_state, shard_parent_state, proposal.message) @@ -249,13 +216,12 @@ def get_shard_state_transition_result( beacon_state: BeaconState, shard: Shard, shard_blocks: Sequence[SignedShardBlock], - on_time_slot: Slot, validate_signature: bool=True, ) -> Tuple[Sequence[SignedShardBlock], Sequence[ShardState], Sequence[Root]]: proposals = [] shard_states = [] shard_state = beacon_state.shard_states[shard] - offset_slots = compute_offset_slots(get_latest_slot_for_shard(beacon_state, shard), on_time_slot) + offset_slots = compute_offset_slots(get_latest_slot_for_shard(beacon_state, shard), Slot(beacon_state.slot + 1)) for slot in offset_slots: proposal, shard_state = get_proposal_at_slot( beacon_state=beacon_state, @@ -281,11 +247,8 @@ Suppose you are a committee member on shard `shard` at slot `current_slot` and y def get_shard_transition(beacon_state: BeaconState, shard: Shard, shard_blocks: Sequence[SignedShardBlock]) -> ShardTransition: - on_time_slot = Slot(beacon_state.slot + 1) - offset_slots = compute_offset_slots(get_latest_slot_for_shard(beacon_state, shard), on_time_slot) - proposals, shard_states, shard_data_roots = get_shard_state_transition_result( - beacon_state, shard, shard_blocks, on_time_slot - ) + offset_slots = compute_offset_slots(get_latest_slot_for_shard(beacon_state, shard), Slot(beacon_state.slot + 1)) + proposals, shard_states, shard_data_roots = get_shard_state_transition_result(beacon_state, shard, shard_blocks) shard_block_lengths = [] proposer_signatures = [] diff --git a/tests/core/pyspec/eth2spec/test/fork_choice/test_on_shard_head.py b/tests/core/pyspec/eth2spec/test/fork_choice/test_on_shard_head.py index ca79cfd23..1a9042960 100644 --- a/tests/core/pyspec/eth2spec/test/fork_choice/test_on_shard_head.py +++ b/tests/core/pyspec/eth2spec/test/fork_choice/test_on_shard_head.py @@ -89,11 +89,11 @@ def apply_shard_and_beacon(spec, state, store, shard_store, shard_blocks_buffer) # Clear buffer shard_blocks_buffer.clear() - signed_beacon_block = state_transition_and_sign_block(spec, state, beacon_block) + signed_beacon_block = state_transition_and_sign_block(spec, state, beacon_block) # transition! add_block_to_store(spec, store, signed_beacon_block) assert spec.get_head(store) == beacon_block.hash_tree_root() - # On shard block at updated `state.slot` + # On shard block at transitioned `state.slot` if is_in_offset_sets(spec, state, shard): # The created shard block would be appended to `shard_blocks_buffer` apply_shard_block(spec, store, shard_store, state, shard_blocks_buffer)