Merge branch 'dev' into JustinDrake-patch-11

.gitignore

@@ -4,3 +4,4 @@
 /.pytest_cache
 
 build/
+output/

specs/core/0_beacon-chain.md

@@ -29,7 +29,6 @@
             - [`AttestationData`](#attestationdata)
             - [`AttestationDataAndCustodyBit`](#attestationdataandcustodybit)
             - [`SlashableAttestation`](#slashableattestation)
-            - [`DepositInput`](#depositinput)
             - [`DepositData`](#depositdata)
             - [`BeaconBlockHeader`](#beaconblockheader)
             - [`Validator`](#validator)
@@ -69,9 +68,7 @@
         - [`get_split_offset`](#get_split_offset)
         - [`get_epoch_committee_count`](#get_epoch_committee_count)
         - [`compute_committee`](#compute_committee)
-        - [`get_previous_epoch_committee_count`](#get_previous_epoch_committee_count)
         - [`get_current_epoch_committee_count`](#get_current_epoch_committee_count)
-        - [`get_next_epoch_committee_count`](#get_next_epoch_committee_count)
         - [`get_crosslink_committees_at_slot`](#get_crosslink_committees_at_slot)
         - [`get_block_root`](#get_block_root)
         - [`get_state_root`](#get_state_root)
@@ -81,7 +78,6 @@
         - [`get_beacon_proposer_index`](#get_beacon_proposer_index)
         - [`verify_merkle_branch`](#verify_merkle_branch)
         - [`get_attestation_participants`](#get_attestation_participants)
-        - [`is_power_of_two`](#is_power_of_two)
         - [`int_to_bytes1`, `int_to_bytes2`, ...](#int_to_bytes1-int_to_bytes2-)
         - [`bytes_to_int`](#bytes_to_int)
         - [`get_effective_balance`](#get_effective_balance)
@@ -237,6 +233,10 @@ Code snippets appearing in `this style` are to be interpreted as Python code.
 | `SLOTS_PER_HISTORICAL_ROOT` | `2**13` (= 8,192) | slots | ~13 hours |
 | `MIN_VALIDATOR_WITHDRAWABILITY_DELAY` | `2**8` (= 256) | epochs | ~27 hours |
 | `PERSISTENT_COMMITTEE_PERIOD` | `2**11` (= 2,048)  | epochs | 9 days  |
+| `MAX_CROSSLINK_EPOCHS` | `2**6` (= 64) |
+
+* `MAX_CROSSLINK_EPOCHS` should be a small constant times `SHARD_COUNT // SLOTS_PER_EPOCH`
+
 
 ### State list lengths
 
@@ -384,7 +384,7 @@ The types are defined topologically to aid in facilitating an executable version
 }
 ```
 
-#### `DepositInput`
+#### `DepositData`
 
 ```python
 {
@@ -392,21 +392,10 @@ The types are defined topologically to aid in facilitating an executable version
     'pubkey': 'bytes48',
     # Withdrawal credentials
     'withdrawal_credentials': 'bytes32',
-    # A BLS signature of this `DepositInput`
-    'proof_of_possession': 'bytes96',
-}
-```
-
-#### `DepositData`
-
-```python
-{
     # Amount in Gwei
     'amount': 'uint64',
-    # Timestamp from deposit contract
+    # Container self-signature
-    'timestamp': 'uint64',
+    'proof_of_possession': 'bytes96',
-    # Deposit input
-    'deposit_input': DepositInput,
 }
 ```
 
@@ -520,7 +509,7 @@ The types are defined topologically to aid in facilitating an executable version
     # Index in the deposit tree
     'index': 'uint64',
     # Data
-    'deposit_data': DepositData,
+    'data': DepositData,
 }
 ```
 
@@ -606,12 +595,7 @@ The types are defined topologically to aid in facilitating an executable version
 
     # Randomness and committees
     'latest_randao_mixes': ['bytes32', LATEST_RANDAO_MIXES_LENGTH],
-    'previous_shuffling_start_shard': 'uint64',
+    'latest_start_shard': 'uint64',
-    'current_shuffling_start_shard': 'uint64',
-    'previous_shuffling_epoch': 'uint64',
-    'current_shuffling_epoch': 'uint64',
-    'previous_shuffling_seed': 'bytes32',
-    'current_shuffling_seed': 'bytes32',
 
     # Finality
     'previous_epoch_attestations': [PendingAttestation],
@@ -668,7 +652,7 @@ def xor(bytes1: Bytes32, bytes2: Bytes32) -> Bytes32:
 
 ### `hash`
 
-The hash function is denoted by `hash`. In Phase 0 the beacon chain is deployed with the same hash function as Ethereum 1.0, i.e. Keccak-256 (also incorrectly known as SHA3).
+The `hash` function is SHA256.
 
 Note: We aim to migrate to a S[T/N]ARK-friendly hash function in a future Ethereum 2.0 deployment phase.
 
@@ -692,7 +676,8 @@ def get_temporary_block_header(block: BeaconBlock) -> BeaconBlockHeader:
         previous_block_root=block.previous_block_root,
         state_root=ZERO_HASH,
         block_body_root=hash_tree_root(block.body),
-        signature=block.signature,
+        # signed_root(block) is used for block id purposes so signature is a stub
+        signature=EMPTY_SIGNATURE,
     )
 ```
 
@@ -888,20 +873,6 @@ def compute_committee(validator_indices: List[ValidatorIndex],
 
 **Note**: this definition and the next few definitions are highly inefficient as algorithms as they re-calculate many sub-expressions. Production implementations are expected to appropriately use caching/memoization to avoid redoing work.
 
-### `get_previous_epoch_committee_count`
-
-```python
-def get_previous_epoch_committee_count(state: BeaconState) -> int:
-    """
-    Return the number of committees in the previous epoch of the given ``state``.
-    """
-    previous_active_validators = get_active_validator_indices(
-        state.validator_registry,
-        state.previous_shuffling_epoch,
-    )
-    return get_epoch_committee_count(len(previous_active_validators))
-```
-
 ### `get_current_epoch_committee_count`
 
 ```python
@@ -911,36 +882,18 @@ def get_current_epoch_committee_count(state: BeaconState) -> int:
     """
     current_active_validators = get_active_validator_indices(
         state.validator_registry,
-        state.current_shuffling_epoch,
+        get_current_epoch(state),
     )
     return get_epoch_committee_count(len(current_active_validators))
 ```
 
-### `get_next_epoch_committee_count`
-
-```python
-def get_next_epoch_committee_count(state: BeaconState) -> int:
-    """
-    Return the number of committees in the next epoch of the given ``state``.
-    """
-    next_active_validators = get_active_validator_indices(
-        state.validator_registry,
-        get_current_epoch(state) + 1,
-    )
-    return get_epoch_committee_count(len(next_active_validators))
-```
-
 ### `get_crosslink_committees_at_slot`
 
 ```python
 def get_crosslink_committees_at_slot(state: BeaconState,
-                                     slot: Slot,
+                                     slot: Slot) -> List[Tuple[List[ValidatorIndex], Shard]]:
-                                     registry_change: bool=False) -> List[Tuple[List[ValidatorIndex], Shard]]:
     """
     Return the list of ``(committee, shard)`` tuples for the ``slot``.
-
-    Note: There are two possible shufflings for crosslink committees for a
-    ``slot`` in the next epoch -- with and without a `registry_change`
     """
     epoch = slot_to_epoch(slot)
     current_epoch = get_current_epoch(state)
@@ -948,40 +901,24 @@ def get_crosslink_committees_at_slot(state: BeaconState,
     next_epoch = current_epoch + 1
 
     assert previous_epoch <= epoch <= next_epoch
+    indices = get_active_validator_indices(
+        state.validator_registry,
+        epoch,
+    )
+    committees_per_epoch = get_epoch_committee_count(len(indices))
 
     if epoch == current_epoch:
-        committees_per_epoch = get_current_epoch_committee_count(state)
+        start_shard = state.latest_start_shard
-        seed = state.current_shuffling_seed
-        shuffling_epoch = state.current_shuffling_epoch
-        shuffling_start_shard = state.current_shuffling_start_shard
     elif epoch == previous_epoch:
-        committees_per_epoch = get_previous_epoch_committee_count(state)
+        start_shard = (state.latest_start_shard - committees_per_epoch) % SHARD_COUNT
-        seed = state.previous_shuffling_seed
-        shuffling_epoch = state.previous_shuffling_epoch
-        shuffling_start_shard = state.previous_shuffling_start_shard
     elif epoch == next_epoch:
-        epochs_since_last_registry_update = current_epoch - state.validator_registry_update_epoch
+        current_epoch_committees = get_current_epoch_committee_count(state)
-        if registry_change:
+        start_shard = (state.latest_start_shard + current_epoch_committees) % SHARD_COUNT
-            committees_per_epoch = get_next_epoch_committee_count(state)
-            seed = generate_seed(state, next_epoch)
-            shuffling_epoch = next_epoch
-            current_committees_per_epoch = get_current_epoch_committee_count(state)
-            shuffling_start_shard = (state.current_shuffling_start_shard + current_committees_per_epoch) % SHARD_COUNT
-        elif epochs_since_last_registry_update > 1 and is_power_of_two(epochs_since_last_registry_update):
-            committees_per_epoch = get_next_epoch_committee_count(state)
-            seed = generate_seed(state, next_epoch)
-            shuffling_epoch = next_epoch
-            shuffling_start_shard = state.current_shuffling_start_shard
-        else:
-            committees_per_epoch = get_current_epoch_committee_count(state)
-            seed = state.current_shuffling_seed
-            shuffling_epoch = state.current_shuffling_epoch
-            shuffling_start_shard = state.current_shuffling_start_shard
 
-    indices = get_active_validator_indices(state.validator_registry, shuffling_epoch)
     committees_per_slot = committees_per_epoch // SLOTS_PER_EPOCH
     offset = slot % SLOTS_PER_EPOCH
-    slot_start_shard = (shuffling_start_shard + committees_per_slot * offset) % SHARD_COUNT
+    slot_start_shard = (start_shard + committees_per_slot * offset) % SHARD_COUNT
+    seed = generate_seed(state, epoch)
 
     return [
         (
@@ -1060,20 +997,26 @@ def generate_seed(state: BeaconState,
 
 ```python
 def get_beacon_proposer_index(state: BeaconState,
-                              slot: Slot,
+                              slot: Slot) -> ValidatorIndex:
-                              registry_change: bool=False) -> ValidatorIndex:
     """
     Return the beacon proposer index for the ``slot``.
+    Due to proposer selection being based upon the validator balances during
+    the epoch in question, this can only be run for the current epoch.
     """
-    epoch = slot_to_epoch(slot)
     current_epoch = get_current_epoch(state)
-    previous_epoch = get_previous_epoch(state)
+    assert slot_to_epoch(slot) == current_epoch
-    next_epoch = current_epoch + 1
 
-    assert previous_epoch <= epoch <= next_epoch
+    first_committee, _ = get_crosslink_committees_at_slot(state, slot)[0]
-
+    i = 0
-    first_committee, _ = get_crosslink_committees_at_slot(state, slot, registry_change)[0]
+    while True:
-    return first_committee[epoch % len(first_committee)]
+        rand_byte = hash(
+            generate_seed(state, current_epoch) +
+            int_to_bytes8(i // 32)
+        )[i % 32]
+        candidate = first_committee[(current_epoch + i) % len(first_committee)]
+        if get_effective_balance(state, candidate) * 256 > MAX_DEPOSIT_AMOUNT * rand_byte:
+            return candidate
+        i += 1
 ```
 
 ### `verify_merkle_branch`
@@ -1119,16 +1062,6 @@ def get_attestation_participants(state: BeaconState,
     return participants
 ```
 
-### `is_power_of_two`
-
-```python
-def is_power_of_two(value: int) -> bool:
-    """
-    Check if ``value`` is a power of two integer.
-    """
-    return (value > 0) and (value & (value - 1) == 0)
-```
-
 ### `int_to_bytes1`, `int_to_bytes2`, ...
 
 `int_to_bytes1(x): return x.to_bytes(1, 'little')`, `int_to_bytes2(x): return x.to_bytes(2, 'little')`, and so on for all integers, particularly 1, 2, 3, 4, 8, 32, 48, 96.
@@ -1333,19 +1266,12 @@ def process_deposit(state: BeaconState, deposit: Deposit) -> None:
     Process a deposit from Ethereum 1.0.
     Note that this function mutates ``state``.
     """
-    deposit_input = deposit.deposit_data.deposit_input
-
-    # Should equal 8 bytes for deposit_data.amount +
-    #              8 bytes for deposit_data.timestamp +
-    #              176 bytes for deposit_data.deposit_input
-    # It should match the deposit_data in the eth1.0 deposit contract
-    serialized_deposit_data = serialize(deposit.deposit_data)
     # Deposits must be processed in order
     assert deposit.index == state.deposit_index
 
     # Verify the Merkle branch
     merkle_branch_is_valid = verify_merkle_branch(
-        leaf=hash(serialized_deposit_data),
+        leaf=hash(serialize(deposit.data)),  # 48 + 32 + 8 + 96 = 184 bytes serialization
         proof=deposit.proof,
         depth=DEPOSIT_CONTRACT_TREE_DEPTH,
         index=deposit.index,
@@ -1360,16 +1286,15 @@ def process_deposit(state: BeaconState, deposit: Deposit) -> None:
     state.deposit_index += 1
 
     validator_pubkeys = [v.pubkey for v in state.validator_registry]
-    pubkey = deposit_input.pubkey
+    pubkey = deposit.data.pubkey
-    amount = deposit.deposit_data.amount
+    amount = deposit.data.amount
-    withdrawal_credentials = deposit_input.withdrawal_credentials
 
     if pubkey not in validator_pubkeys:
         # Verify the proof of possession
         proof_is_valid = bls_verify(
-            pubkey=deposit_input.pubkey,
+            pubkey=pubkey,
-            message_hash=signed_root(deposit_input),
+            message_hash=signed_root(deposit.data),
-            signature=deposit_input.proof_of_possession,
+            signature=deposit.data.proof_of_possession,
             domain=get_domain(
                 state.fork,
                 get_current_epoch(state),
@@ -1382,7 +1307,7 @@ def process_deposit(state: BeaconState, deposit: Deposit) -> None:
         # Add new validator
         validator = Validator(
             pubkey=pubkey,
-            withdrawal_credentials=withdrawal_credentials,
+            withdrawal_credentials=deposit.data.withdrawal_credentials,
             activation_epoch=FAR_FUTURE_EPOCH,
             exit_epoch=FAR_FUTURE_EPOCH,
             withdrawable_epoch=FAR_FUTURE_EPOCH,
@@ -1488,11 +1413,11 @@ The initial deployment phases of Ethereum 2.0 are implemented without consensus
 
 ### Deposit arguments
 
-The deposit contract has a single `deposit` function which takes as argument a SimpleSerialize'd `DepositInput`.
+The deposit contract has a single `deposit` function which takes as argument a SimpleSerialize'd `DepositData`.
 
 ### Withdrawal credentials
 
-One of the `DepositInput` fields is `withdrawal_credentials`. It is a commitment to credentials for withdrawals to shards. The first byte of `withdrawal_credentials` is a version number. As of now the only expected format is as follows:
+One of the `DepositData` fields is `withdrawal_credentials`. It is a commitment to credentials for withdrawals to shards. The first byte of `withdrawal_credentials` is a version number. As of now the only expected format is as follows:
 
 * `withdrawal_credentials[:1] == BLS_WITHDRAWAL_PREFIX_BYTE`
 * `withdrawal_credentials[1:] == hash(withdrawal_pubkey)[1:]` where `withdrawal_pubkey` is a BLS pubkey
@@ -1590,12 +1515,7 @@ def get_genesis_beacon_state(genesis_validator_deposits: List[Deposit],
 
         # Randomness and committees
         latest_randao_mixes=Vector([ZERO_HASH for _ in range(LATEST_RANDAO_MIXES_LENGTH)]),
-        previous_shuffling_start_shard=GENESIS_START_SHARD,
+        latest_start_shard=GENESIS_START_SHARD,
-        current_shuffling_start_shard=GENESIS_START_SHARD,
-        previous_shuffling_epoch=GENESIS_EPOCH - 1,
-        current_shuffling_epoch=GENESIS_EPOCH,
-        previous_shuffling_seed=ZERO_HASH,
-        current_shuffling_seed=ZERO_HASH,
 
         # Finality
         previous_epoch_attestations=[],
@@ -1635,7 +1555,6 @@ def get_genesis_beacon_state(genesis_validator_deposits: List[Deposit],
     genesis_active_index_root = hash_tree_root(get_active_validator_indices(state.validator_registry, GENESIS_EPOCH))
     for index in range(LATEST_ACTIVE_INDEX_ROOTS_LENGTH):
         state.latest_active_index_roots[index] = genesis_active_index_root
-    state.current_shuffling_seed = generate_seed(state, GENESIS_EPOCH)
 
     return state
 ```
@@ -1753,7 +1672,7 @@ def cache_state(state: BeaconState) -> None:
         state.latest_block_header.state_root = previous_slot_state_root
 
     # store latest known block for previous slot
-    state.latest_block_roots[state.slot % SLOTS_PER_HISTORICAL_ROOT] = hash_tree_root(state.latest_block_header)
+    state.latest_block_roots[state.slot % SLOTS_PER_HISTORICAL_ROOT] = signed_root(state.latest_block_header)
 ```
 
 ### Per-epoch processing
@@ -1910,7 +1829,7 @@ Run the following function:
 ```python
 def process_crosslinks(state: BeaconState) -> None:
     current_epoch = get_current_epoch(state)
-    previous_epoch = current_epoch - 1
+    previous_epoch = max(current_epoch - 1, GENESIS_EPOCH)
     next_epoch = current_epoch + 1
     for slot in range(get_epoch_start_slot(previous_epoch), get_epoch_start_slot(next_epoch)):
         for crosslink_committee, shard in get_crosslink_committees_at_slot(state, slot):
@@ -1919,7 +1838,7 @@ def process_crosslinks(state: BeaconState) -> None:
             total_balance = get_total_balance(state, crosslink_committee)
             if 3 * participating_balance >= 2 * total_balance:
                 state.latest_crosslinks[shard] = Crosslink(
-                    epoch=slot_to_epoch(slot),
+                    epoch=min(slot_to_epoch(slot), state.latest_crosslinks[shard].epoch + MAX_CROSSLINK_EPOCHS),
                     crosslink_data_root=winning_root
                 )
 ```
@@ -1954,10 +1873,11 @@ def get_base_reward(state: BeaconState, index: ValidatorIndex) -> Gwei:
 
 ```python
 def get_inactivity_penalty(state: BeaconState, index: ValidatorIndex, epochs_since_finality: int) -> Gwei:
-    return (
+    if epochs_since_finality <= 4:
-        get_base_reward(state, index) +
+        extra_penalty = 0
-        get_effective_balance(state, index) * epochs_since_finality // INACTIVITY_PENALTY_QUOTIENT // 2
+    else:
-    )
+        extra_penalty = get_effective_balance(state, index) * epochs_since_finality // INACTIVITY_PENALTY_QUOTIENT // 2
+    return get_base_reward(state, index) + extra_penalty
 ```
 
 Note: When applying penalties in the following balance recalculations implementers should make sure the `uint64` does not underflow.
@@ -1966,23 +1886,10 @@ Note: When applying penalties in the following balance recalculations implemente
 
 ```python
 def get_justification_and_finalization_deltas(state: BeaconState) -> Tuple[List[Gwei], List[Gwei]]:
-    epochs_since_finality = get_current_epoch(state) + 1 - state.finalized_epoch
+    current_epoch = get_current_epoch(state)
-    if epochs_since_finality <= 4:
+    epochs_since_finality = current_epoch + 1 - state.finalized_epoch
-        return compute_normal_justification_and_finalization_deltas(state)
+    rewards = [0 for index in range(len(state.validator_registry))]
-    else:
+    penalties = [0 for index in range(len(state.validator_registry))]
-        return compute_inactivity_leak_deltas(state)
-```
-
-When blocks are finalizing normally...
-
-```python
-def compute_normal_justification_and_finalization_deltas(state: BeaconState) -> Tuple[List[Gwei], List[Gwei]]:
-    # deltas[0] for rewards
-    # deltas[1] for penalties
-    deltas = [
-        [0 for index in range(len(state.validator_registry))],
-        [0 for index in range(len(state.validator_registry))]
-    ]
     # Some helper variables
     boundary_attestations = get_previous_epoch_boundary_attestations(state)
     boundary_attesting_balance = get_attesting_balance(state, boundary_attestations)
@@ -1990,76 +1897,44 @@ def compute_normal_justification_and_finalization_deltas(state: BeaconState) ->
     total_attesting_balance = get_attesting_balance(state, state.previous_epoch_attestations)
     matching_head_attestations = get_previous_epoch_matching_head_attestations(state)
     matching_head_balance = get_attesting_balance(state, matching_head_attestations)
+    eligible_validators = [
+        index for index, validator in enumerate(state.validator_registry)
+        if (
+            is_active_validator(validator, current_epoch) or
+            (validator.slashed and current_epoch < validator.withdrawable_epoch)
+        )
+    ]
     # Process rewards or penalties for all validators
-    for index in get_active_validator_indices(state.validator_registry, get_previous_epoch(state)):
+    for index in eligible_validators:
+        base_reward = get_base_reward(state, index)
         # Expected FFG source
         if index in get_attesting_indices(state, state.previous_epoch_attestations):
-            deltas[0][index] += get_base_reward(state, index) * total_attesting_balance // total_balance
+            rewards[index] += base_reward * total_attesting_balance // total_balance
             # Inclusion speed bonus
-            deltas[0][index] += (
+            rewards[index] += (
-                get_base_reward(state, index) * MIN_ATTESTATION_INCLUSION_DELAY //
+                base_reward * MIN_ATTESTATION_INCLUSION_DELAY //
                 inclusion_distance(state, index)
             )
         else:
-            deltas[1][index] += get_base_reward(state, index)
+            penalties[index] += base_reward
         # Expected FFG target
         if index in get_attesting_indices(state, boundary_attestations):
-            deltas[0][index] += get_base_reward(state, index) * boundary_attesting_balance // total_balance
+            rewards[index] += base_reward * boundary_attesting_balance // total_balance
         else:
-            deltas[1][index] += get_base_reward(state, index)
+            penalties[index] += get_inactivity_penalty(state, index, epochs_since_finality)
         # Expected head
         if index in get_attesting_indices(state, matching_head_attestations):
-            deltas[0][index] += get_base_reward(state, index) * matching_head_balance // total_balance
+            rewards[index] += base_reward * matching_head_balance // total_balance
         else:
-            deltas[1][index] += get_base_reward(state, index)
+            penalties[index] += base_reward
         # Proposer bonus
         if index in get_attesting_indices(state, state.previous_epoch_attestations):
             proposer_index = get_beacon_proposer_index(state, inclusion_slot(state, index))
-            deltas[0][proposer_index] += get_base_reward(state, index) // PROPOSER_REWARD_QUOTIENT
+            rewards[proposer_index] += base_reward // PROPOSER_REWARD_QUOTIENT
-    return deltas
+        # Take away max rewards if we're not finalizing
-```
+        if epochs_since_finality > 4:
-
+            penalties[index] += base_reward * 4
-When blocks are not finalizing normally...
+    return [rewards, penalties]
-
-```python
-def compute_inactivity_leak_deltas(state: BeaconState) -> Tuple[List[Gwei], List[Gwei]]:
-    # deltas[0] for rewards
-    # deltas[1] for penalties
-    deltas = [
-        [0 for index in range(len(state.validator_registry))],
-        [0 for index in range(len(state.validator_registry))]
-    ]
-    boundary_attestations = get_previous_epoch_boundary_attestations(state)
-    matching_head_attestations = get_previous_epoch_matching_head_attestations(state)
-    active_validator_indices = get_active_validator_indices(state.validator_registry, get_previous_epoch(state))
-    epochs_since_finality = get_current_epoch(state) + 1 - state.finalized_epoch
-    for index in active_validator_indices:
-        if index not in get_attesting_indices(state, state.previous_epoch_attestations):
-            deltas[1][index] += get_inactivity_penalty(state, index, epochs_since_finality)
-        else:
-            # If a validator did attest, apply a small penalty for getting attestations included late
-            deltas[0][index] += (
-                get_base_reward(state, index) * MIN_ATTESTATION_INCLUSION_DELAY //
-                inclusion_distance(state, index)
-            )
-            deltas[1][index] += get_base_reward(state, index)
-        if index not in get_attesting_indices(state, boundary_attestations):
-            deltas[1][index] += get_inactivity_penalty(state, index, epochs_since_finality)
-        if index not in get_attesting_indices(state, matching_head_attestations):
-            deltas[1][index] += get_base_reward(state, index)
-    # Penalize slashed-but-inactive validators as though they were active but offline
-    for index in range(len(state.validator_registry)):
-        eligible = (
-            index not in active_validator_indices and
-            state.validator_registry[index].slashed and
-            get_current_epoch(state) < state.validator_registry[index].withdrawable_epoch
-        )
-        if eligible:
-            deltas[1][index] += (
-                2 * get_inactivity_penalty(state, index, epochs_since_finality) +
-                get_base_reward(state, index)
-            )
-    return deltas
 ```
 
 ##### Crosslinks
@@ -2119,22 +1994,6 @@ def process_ejections(state: BeaconState) -> None:
 
 #### Validator registry and shuffling seed data
 
-```python
-def should_update_validator_registry(state: BeaconState) -> bool:
-    # Must have finalized a new block
-    if state.finalized_epoch <= state.validator_registry_update_epoch:
-        return False
-    # Must have processed new crosslinks on all shards of the current epoch
-    shards_to_check = [
-        (state.current_shuffling_start_shard + i) % SHARD_COUNT
-        for i in range(get_current_epoch_committee_count(state))
-    ]
-    for shard in shards_to_check:
-        if state.latest_crosslinks[shard].epoch <= state.validator_registry_update_epoch:
-            return False
-    return True
-```
-
 ```python
 def update_validator_registry(state: BeaconState) -> None:
     """
@@ -2188,30 +2047,14 @@ def update_validator_registry(state: BeaconState) -> None:
 Run the following function:
 
 ```python
-def update_registry_and_shuffling_data(state: BeaconState) -> None:
+def update_registry(state: BeaconState) -> None:
-    # First set previous shuffling data to current shuffling data
-    state.previous_shuffling_epoch = state.current_shuffling_epoch
-    state.previous_shuffling_start_shard = state.current_shuffling_start_shard
-    state.previous_shuffling_seed = state.current_shuffling_seed
-    current_epoch = get_current_epoch(state)
-    next_epoch = current_epoch + 1
     # Check if we should update, and if so, update
-    if should_update_validator_registry(state):
+    if state.finalized_epoch > state.validator_registry_update_epoch:
         update_validator_registry(state)
-        # If we update the registry, update the shuffling data and shards as well
+    state.latest_start_shard = (
-        state.current_shuffling_epoch = next_epoch
+        state.latest_start_shard +
-        state.current_shuffling_start_shard = (
+        get_current_epoch_committee_count(state)
-            state.current_shuffling_start_shard +
+    ) % SHARD_COUNT
-            get_current_epoch_committee_count(state) % SHARD_COUNT
-        )
-        state.current_shuffling_seed = generate_seed(state, state.current_shuffling_epoch)
-    else:
-        # If processing at least one crosslink keeps failing, then reshuffle every power of two,
-        # but don't update the current_shuffling_start_shard
-        epochs_since_last_registry_update = current_epoch - state.validator_registry_update_epoch
-        if epochs_since_last_registry_update > 1 and is_power_of_two(epochs_since_last_registry_update):
-            state.current_shuffling_epoch = next_epoch
-            state.current_shuffling_seed = generate_seed(state, state.current_shuffling_epoch)
 ```
 
 **Invariant**: the active index root that is hashed into the shuffling seed actually is the `hash_tree_root` of the validator set that is used for that epoch.
@@ -2319,7 +2162,7 @@ def process_block_header(state: BeaconState, block: BeaconBlock) -> None:
     # Verify that the slots match
     assert block.slot == state.slot
     # Verify that the parent matches
-    assert block.previous_block_root == hash_tree_root(state.latest_block_header)
+    assert block.previous_block_root == signed_root(state.latest_block_header)
     # Save current block as the new latest block
     state.latest_block_header = get_temporary_block_header(block)
     # Verify proposer is not slashed
@@ -2462,7 +2305,8 @@ def process_attestation(state: BeaconState, attestation: Attestation) -> None:
         attestation.data.previous_crosslink,  # Case 1: latest crosslink matches previous crosslink
         Crosslink(                            # Case 2: latest crosslink matches current crosslink
             crosslink_data_root=attestation.data.crosslink_data_root,
-            epoch=target_epoch,
+            epoch=min(slot_to_epoch(attestation.data.slot),
+                      attestation.data.previous_crosslink.epoch + MAX_CROSSLINK_EPOCHS)
         ),
     }
 

specs/validator/0_beacon-chain-validator.md

@@ -331,22 +331,19 @@ signed_attestation_data = bls_sign(
 
 ## Validator assignments
 
-A validator can get the current and previous epoch committee assignments using the following helper via `get_committee_assignment(state, epoch, validator_index)` where `previous_epoch <= epoch <= current_epoch`.
+A validator can get the current, previous, and next epoch committee assignments using the following helper via `get_committee_assignment(state, epoch, validator_index)` where `previous_epoch <= epoch <= next_epoch`.
 
 ```python
 def get_committee_assignment(
         state: BeaconState,
         epoch: Epoch,
-        validator_index: ValidatorIndex,
+        validator_index: ValidatorIndex) -> Tuple[List[ValidatorIndex], Shard, Slot]:
-        registry_change: bool=False) -> Tuple[List[ValidatorIndex], Shard, Slot, bool]:
     """
-    Return the committee assignment in the ``epoch`` for ``validator_index`` and ``registry_change``.
+    Return the committee assignment in the ``epoch`` for ``validator_index``.
     ``assignment`` returned is a tuple of the following form:
         * ``assignment[0]`` is the list of validators in the committee
         * ``assignment[1]`` is the shard to which the committee is assigned
         * ``assignment[2]`` is the slot at which the committee is assigned
-        * ``assignment[3]`` is a bool signalling if the validator is expected to propose
-            a beacon block at the assigned slot.
     """
     previous_epoch = get_previous_epoch(state)
     next_epoch = get_current_epoch(state) + 1
@@ -357,7 +354,6 @@ def get_committee_assignment(
         crosslink_committees = get_crosslink_committees_at_slot(
             state,
             slot,
-            registry_change=registry_change,
         )
         selected_committees = [
             committee  # Tuple[List[ValidatorIndex], Shard]
@@ -367,28 +363,33 @@ def get_committee_assignment(
         if len(selected_committees) > 0:
             validators = selected_committees[0][0]
             shard = selected_committees[0][1]
-            is_proposer = validator_index == get_beacon_proposer_index(state, slot, registry_change=registry_change)
 
-            assignment = (validators, shard, slot, is_proposer)
+            assignment = (validators, shard, slot)
             return assignment
 ```
 
+A validator can use the following function to see if they are supposed to propose during their assigned committee slot. This function can only be run during the epoch of the slot in question and can not reliably be used to predict an epoch in advance.
+
+```python
+def is_proposer_at_slot(state: BeaconState,
+                        slot: Slot,
+                        validator_index: ValidatorIndex) -> bool:
+    current_epoch = get_current_epoch(state)
+    assert slot_to_epoch(slot) == current_epoch
+
+    return get_beacon_proposer_index(state, slot) == validator_index
+```
+
+_Note_: If a validator is assigned to the 0th slot of an epoch, the validator must run an empty slot transition from the previous epoch into the 0th slot of the epoch to be able to check if they are a proposer at that slot.
+
+
 ### Lookahead
 
-The beacon chain shufflings are designed to provide a minimum of 1 epoch lookahead on the validator's upcoming assignments of proposing and attesting dictated by the shuffling and slot.
+The beacon chain shufflings are designed to provide a minimum of 1 epoch lookahead on the validator's upcoming committee assignments for attesting dictated by the shuffling and slot. Note that this lookahead does not apply to proposing which must checked during the epoch in question.
 
-There are three possibilities for the shuffling at the next epoch:
+`get_committee_assignment` should be called at the start of each epoch to get the assignment for the next epoch (`current_epoch + 1`). A validator should plan for future assignments which involves noting at which future slot one will have to attest and also which shard one should begin syncing (in phase 1+).
-1. The shuffling changes due to a "validator registry change".
-2. The shuffling changes due to `epochs_since_last_registry_update` being an exact power of 2 greater than 1.
-3. The shuffling remains the same (i.e. the validator is in the same shard committee).
 
-Either (2) or (3) occurs if (1) fails. The choice between (2) and (3) is deterministic based upon `epochs_since_last_registry_update`.
+Specifically, a validator should call `get_committee_assignment(state, next_epoch, validator_index)` when checking for next epoch assignments.
-
-When querying for assignments in the next epoch there are two options -- with and without a `registry_change` -- which is the optional fourth parameter of the `get_committee_assignment`.
-
-`get_committee_assignment` should be called at the start of each epoch to get the assignment for the next epoch (`current_epoch + 1`). A validator should always plan for assignments from both values of `registry_change` unless the validator can concretely eliminate one of the options. Planning for future assignments involves noting at which future slot one might have to attest and propose and also which shard one should begin syncing (in phase 1+).
-
-Specifically, a validator should call both `get_committee_assignment(state, next_epoch, validator_index, registry_change=True)` and `get_committee_assignment(state, next_epoch, validator_index, registry_change=False)` when checking for next epoch assignments.
 
 ## How to avoid slashing
 

tests/phase0/block_processing/test_process_attestation.py

@@ -0,0 +1,153 @@
+from copy import deepcopy
+import pytest
+
+import build.phase0.spec as spec
+
+from build.phase0.state_transition import (
+    state_transition,
+)
+from build.phase0.spec import (
+    ZERO_HASH,
+    get_current_epoch,
+    process_attestation,
+    slot_to_epoch,
+)
+from tests.phase0.helpers import (
+    build_empty_block_for_next_slot,
+    get_valid_attestation,
+)
+
+
+# mark entire file as 'attestations'
+pytestmark = pytest.mark.attestations
+
+
+def run_attestation_processing(state, attestation, valid=True):
+    """
+    Run ``process_attestation`` returning the pre and post state.
+    If ``valid == False``, run expecting ``AssertionError``
+    """
+    post_state = deepcopy(state)
+
+    if not valid:
+        with pytest.raises(AssertionError):
+            process_attestation(post_state, attestation)
+        return state, None
+
+    process_attestation(post_state, attestation)
+
+    current_epoch = get_current_epoch(state)
+    target_epoch = slot_to_epoch(attestation.data.slot)
+    if target_epoch == current_epoch:
+        assert len(post_state.current_epoch_attestations) == len(state.current_epoch_attestations) + 1
+    else:
+        assert len(post_state.previous_epoch_attestations) == len(state.previous_epoch_attestations) + 1
+
+    return state, post_state
+
+
+def test_success(state):
+    attestation = get_valid_attestation(state)
+    state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
+
+    pre_state, post_state = run_attestation_processing(state, attestation)
+
+    return pre_state, attestation, post_state
+
+
+def test_success_prevous_epoch(state):
+    attestation = get_valid_attestation(state)
+    block = build_empty_block_for_next_slot(state)
+    block.slot = state.slot + spec.SLOTS_PER_EPOCH
+    state_transition(state, block)
+
+    pre_state, post_state = run_attestation_processing(state, attestation)
+
+    return pre_state, attestation, post_state
+
+
+def test_before_inclusion_delay(state):
+    attestation = get_valid_attestation(state)
+    # do not increment slot to allow for inclusion delay
+
+    pre_state, post_state = run_attestation_processing(state, attestation, False)
+
+    return pre_state, attestation, post_state
+
+
+def test_after_epoch_slots(state):
+    attestation = get_valid_attestation(state)
+    block = build_empty_block_for_next_slot(state)
+    # increment past latest inclusion slot
+    block.slot = state.slot + spec.SLOTS_PER_EPOCH + 1
+    state_transition(state, block)
+
+    pre_state, post_state = run_attestation_processing(state, attestation, False)
+
+    return pre_state, attestation, post_state
+
+
+def test_bad_source_epoch(state):
+    attestation = get_valid_attestation(state)
+    state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
+
+    attestation.data.source_epoch += 10
+
+    pre_state, post_state = run_attestation_processing(state, attestation, False)
+
+    return pre_state, attestation, post_state
+
+
+def test_bad_source_root(state):
+    attestation = get_valid_attestation(state)
+    state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
+
+    attestation.data.source_root = b'\x42'*32
+
+    pre_state, post_state = run_attestation_processing(state, attestation, False)
+
+    return pre_state, attestation, post_state
+
+
+def test_non_zero_crosslink_data_root(state):
+    attestation = get_valid_attestation(state)
+    state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
+
+    attestation.data.crosslink_data_root = b'\x42'*32
+
+    pre_state, post_state = run_attestation_processing(state, attestation, False)
+
+    return pre_state, attestation, post_state
+
+
+def test_bad_previous_crosslink(state):
+    attestation = get_valid_attestation(state)
+    state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
+
+    state.latest_crosslinks[attestation.data.shard].epoch += 10
+
+    pre_state, post_state = run_attestation_processing(state, attestation, False)
+
+    return pre_state, attestation, post_state
+
+
+def test_non_empty_custody_bitfield(state):
+    attestation = get_valid_attestation(state)
+    state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
+
+    attestation.custody_bitfield = b'\x01' + attestation.custody_bitfield[1:]
+
+    pre_state, post_state = run_attestation_processing(state, attestation, False)
+
+    return pre_state, attestation, post_state
+
+
+def test_empty_aggregation_bitfield(state):
+    attestation = get_valid_attestation(state)
+    state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
+
+    attestation.aggregation_bitfield = b'\x00' * len(attestation.aggregation_bitfield)
+
+    pre_state, post_state = run_attestation_processing(state, attestation, False)
+
+    return pre_state, attestation, post_state

tests/phase0/block_processing/test_process_deposit.py

@@ -4,12 +4,14 @@ import pytest
 import build.phase0.spec as spec
 
 from build.phase0.spec import (
-    Deposit,
     get_balance,
+    ZERO_HASH,
     process_deposit,
 )
 from tests.phase0.helpers import (
     build_deposit,
+    privkeys,
+    pubkeys,
 )
 
 
@@ -17,8 +19,10 @@ from tests.phase0.helpers import (
 pytestmark = pytest.mark.voluntary_exits
 
 
-def test_success(state, deposit_data_leaves, pubkeys, privkeys):
+def test_success(state):
     pre_state = deepcopy(state)
+    # fill previous deposits with zero-hash
+    deposit_data_leaves = [ZERO_HASH] * len(pre_state.validator_registry)
 
     index = len(deposit_data_leaves)
     pubkey = pubkeys[index]
@@ -47,8 +51,9 @@ def test_success(state, deposit_data_leaves, pubkeys, privkeys):
     return pre_state, deposit, post_state
 
 
-def test_success_top_up(state, deposit_data_leaves, pubkeys, privkeys):
+def test_success_top_up(state):
     pre_state = deepcopy(state)
+    deposit_data_leaves = [ZERO_HASH] * len(pre_state.validator_registry)
 
     validator_index = 0
     amount = spec.MAX_DEPOSIT_AMOUNT // 4
@@ -78,8 +83,9 @@ def test_success_top_up(state, deposit_data_leaves, pubkeys, privkeys):
     return pre_state, deposit, post_state
 
 
-def test_wrong_index(state, deposit_data_leaves, pubkeys, privkeys):
+def test_wrong_index(state):
     pre_state = deepcopy(state)
+    deposit_data_leaves = [ZERO_HASH] * len(pre_state.validator_registry)
 
     index = len(deposit_data_leaves)
     pubkey = pubkeys[index]
@@ -106,8 +112,9 @@ def test_wrong_index(state, deposit_data_leaves, pubkeys, privkeys):
     return pre_state, deposit, None
 
 
-def test_bad_merkle_proof(state, deposit_data_leaves, pubkeys, privkeys):
+def test_bad_merkle_proof(state):
     pre_state = deepcopy(state)
+    deposit_data_leaves = [ZERO_HASH] * len(pre_state.validator_registry)
 
     index = len(deposit_data_leaves)
     pubkey = pubkeys[index]

tests/phase0/block_processing/test_voluntary_exit.py

@@ -10,6 +10,7 @@ from build.phase0.spec import (
 )
 from tests.phase0.helpers import (
     build_voluntary_exit,
+    pubkey_to_privkey,
 )
 
 
@@ -17,7 +18,7 @@ from tests.phase0.helpers import (
 pytestmark = pytest.mark.voluntary_exits
 
 
-def test_success(state, pub_to_priv):
+def test_success(state):
     pre_state = deepcopy(state)
     #
     # setup pre_state
@@ -30,7 +31,7 @@ def test_success(state, pub_to_priv):
     #
     current_epoch = get_current_epoch(pre_state)
     validator_index = get_active_validator_indices(pre_state.validator_registry, current_epoch)[0]
-    privkey = pub_to_priv[pre_state.validator_registry[validator_index].pubkey]
+    privkey = pubkey_to_privkey[pre_state.validator_registry[validator_index].pubkey]
 
     voluntary_exit = build_voluntary_exit(
         pre_state,
@@ -52,11 +53,11 @@ def test_success(state, pub_to_priv):
     return pre_state, voluntary_exit, post_state
 
 
-def test_validator_not_active(state, pub_to_priv):
+def test_validator_not_active(state):
     pre_state = deepcopy(state)
     current_epoch = get_current_epoch(pre_state)
     validator_index = get_active_validator_indices(pre_state.validator_registry, current_epoch)[0]
-    privkey = pub_to_priv[pre_state.validator_registry[validator_index].pubkey]
+    privkey = pubkey_to_privkey[pre_state.validator_registry[validator_index].pubkey]
 
     #
     # setup pre_state
@@ -79,7 +80,7 @@ def test_validator_not_active(state, pub_to_priv):
     return pre_state, voluntary_exit, None
 
 
-def test_validator_already_exited(state, pub_to_priv):
+def test_validator_already_exited(state):
     pre_state = deepcopy(state)
     #
     # setup pre_state
@@ -89,7 +90,7 @@ def test_validator_already_exited(state, pub_to_priv):
 
     current_epoch = get_current_epoch(pre_state)
     validator_index = get_active_validator_indices(pre_state.validator_registry, current_epoch)[0]
-    privkey = pub_to_priv[pre_state.validator_registry[validator_index].pubkey]
+    privkey = pubkey_to_privkey[pre_state.validator_registry[validator_index].pubkey]
 
     # but validator already has exited
     pre_state.validator_registry[validator_index].exit_epoch = current_epoch + 2
@@ -110,7 +111,7 @@ def test_validator_already_exited(state, pub_to_priv):
     return pre_state, voluntary_exit, None
 
 
-def test_validator_already_initiated_exit(state, pub_to_priv):
+def test_validator_already_initiated_exit(state):
     pre_state = deepcopy(state)
     #
     # setup pre_state
@@ -120,7 +121,7 @@ def test_validator_already_initiated_exit(state, pub_to_priv):
 
     current_epoch = get_current_epoch(pre_state)
     validator_index = get_active_validator_indices(pre_state.validator_registry, current_epoch)[0]
-    privkey = pub_to_priv[pre_state.validator_registry[validator_index].pubkey]
+    privkey = pubkey_to_privkey[pre_state.validator_registry[validator_index].pubkey]
 
     # but validator already has initiated exit
     pre_state.validator_registry[validator_index].initiated_exit = True
@@ -141,14 +142,14 @@ def test_validator_already_initiated_exit(state, pub_to_priv):
     return pre_state, voluntary_exit, None
 
 
-def test_validator_not_active_long_enough(state, pub_to_priv):
+def test_validator_not_active_long_enough(state):
     pre_state = deepcopy(state)
     #
     # setup pre_state
     #
     current_epoch = get_current_epoch(pre_state)
     validator_index = get_active_validator_indices(pre_state.validator_registry, current_epoch)[0]
-    privkey = pub_to_priv[pre_state.validator_registry[validator_index].pubkey]
+    privkey = pubkey_to_privkey[pre_state.validator_registry[validator_index].pubkey]
 
     # but validator already has initiated exit
     pre_state.validator_registry[validator_index].initiated_exit = True

tests/phase0/conftest.py

@@ -3,9 +3,6 @@ import pytest
 from build.phase0 import spec
 
 from tests.phase0.helpers import (
-    privkeys_list,
-    pubkeys_list,
-    pubkey_to_privkey,
     create_genesis_state,
 )
 
@@ -25,21 +22,6 @@ MINIMAL_CONFIG = {
 }
 
 
-@pytest.fixture
-def privkeys():
-    return privkeys_list
-
-
-@pytest.fixture
-def pubkeys():
-    return pubkeys_list
-
-
-@pytest.fixture
-def pub_to_priv():
-    return pubkey_to_privkey
-
-
 def overwrite_spec_config(config):
     for field in config:
         setattr(spec, field, config[field])

tests/phase0/helpers.py

@@ -9,17 +9,20 @@ from build.phase0.spec import (
     EMPTY_SIGNATURE,
     ZERO_HASH,
     # SSZ
+    Attestation,
     AttestationData,
+    AttestationDataAndCustodyBit,
     BeaconBlockHeader,
     Deposit,
-    DepositInput,
     DepositData,
     Eth1Data,
     ProposerSlashing,
     VoluntaryExit,
     # functions
     get_active_validator_indices,
+    get_attestation_participants,
     get_block_root,
+    get_crosslink_committees_at_slot,
     get_current_epoch,
     get_domain,
     get_empty_block,
@@ -35,27 +38,25 @@ from build.phase0.utils.merkle_minimal import (
 )
 
 
-privkeys_list = [i + 1 for i in range(1000)]
+privkeys = [i + 1 for i in range(1000)]
-pubkeys_list = [bls.privtopub(privkey) for privkey in privkeys_list]
+pubkeys = [bls.privtopub(privkey) for privkey in privkeys]
-pubkey_to_privkey = {pubkey: privkey for privkey, pubkey in zip(privkeys_list, pubkeys_list)}
+pubkey_to_privkey = {pubkey: privkey for privkey, pubkey in zip(privkeys, pubkeys)}
 
 
-def create_mock_genesis_validator_deposits(num_validators, deposit_data_leaves):
+def create_mock_genesis_validator_deposits(num_validators, deposit_data_leaves=None):
-    deposit_timestamp = 0
+    if not deposit_data_leaves:
+        deposit_data_leaves = []
     proof_of_possession = b'\x33' * 96
 
     deposit_data_list = []
     for i in range(num_validators):
-        pubkey = pubkeys_list[i]
+        pubkey = pubkeys[i]
         deposit_data = DepositData(
-            amount=spec.MAX_DEPOSIT_AMOUNT,
-            timestamp=deposit_timestamp,
-            deposit_input=DepositInput(
             pubkey=pubkey,
             # insecurely use pubkey as withdrawal key as well
             withdrawal_credentials=spec.BLS_WITHDRAWAL_PREFIX_BYTE + hash(pubkey)[1:],
+            amount=spec.MAX_DEPOSIT_AMOUNT,
             proof_of_possession=proof_of_possession,
-            ),
         )
         item = hash(deposit_data.serialize())
         deposit_data_leaves.append(item)
@@ -70,12 +71,12 @@ def create_mock_genesis_validator_deposits(num_validators, deposit_data_leaves):
         genesis_validator_deposits.append(Deposit(
             proof=list(get_merkle_proof(tree, item_index=i)),
             index=i,
-            deposit_data=deposit_data_list[i]
+            data=deposit_data_list[i]
         ))
     return genesis_validator_deposits, root
 
 
-def create_genesis_state(num_validators, deposit_data_leaves):
+def create_genesis_state(num_validators, deposit_data_leaves=None):
     initial_deposits, deposit_root = create_mock_genesis_validator_deposits(
         num_validators,
         deposit_data_leaves,
@@ -105,19 +106,20 @@ def build_empty_block_for_next_slot(state):
     previous_block_header = deepcopy(state.latest_block_header)
     if previous_block_header.state_root == spec.ZERO_HASH:
         previous_block_header.state_root = state.hash_tree_root()
-    empty_block.previous_block_root = previous_block_header.hash_tree_root()
+    empty_block.previous_block_root = signed_root(previous_block_header)
     return empty_block
 
 
 def build_deposit_data(state, pubkey, privkey, amount):
-    deposit_input = DepositInput(
+    deposit_data = DepositData(
         pubkey=pubkey,
         # insecurely use pubkey as withdrawal key as well
         withdrawal_credentials=spec.BLS_WITHDRAWAL_PREFIX_BYTE + hash(pubkey)[1:],
+        amount=amount,
         proof_of_possession=EMPTY_SIGNATURE,
     )
     proof_of_possession = bls.sign(
-        message_hash=signed_root(deposit_input),
+        message_hash=signed_root(deposit_data),
         privkey=privkey,
         domain=get_domain(
             state.fork,
@@ -125,12 +127,7 @@ def build_deposit_data(state, pubkey, privkey, amount):
             spec.DOMAIN_DEPOSIT,
         )
     )
-    deposit_input.proof_of_possession = proof_of_possession
+    deposit_data.proof_of_possession = proof_of_possession
-    deposit_data = DepositData(
-        amount=amount,
-        timestamp=0,
-        deposit_input=deposit_input,
-    )
     return deposit_data
 
 
@@ -199,7 +196,7 @@ def build_deposit(state,
     deposit = Deposit(
         proof=list(proof),
         index=index,
-        deposit_data=deposit_data,
+        data=deposit_data,
     )
 
     return deposit, root, deposit_data_leaves
@@ -243,3 +240,49 @@ def get_valid_proposer_slashing(state):
         header_1=header_1,
         header_2=header_2,
     )
+
+
+def get_valid_attestation(state, slot=None):
+    if slot is None:
+        slot = state.slot
+    shard = state.latest_start_shard
+    attestation_data = build_attestation_data(state, slot, shard)
+
+    crosslink_committees = get_crosslink_committees_at_slot(state, slot)
+    crosslink_committee = [committee for committee, _shard in crosslink_committees if _shard == attestation_data.shard][0]
+
+    committee_size = len(crosslink_committee)
+    bitfield_length = (committee_size + 7) // 8
+    aggregation_bitfield = b'\x01' + b'\x00' * (bitfield_length - 1)
+    custody_bitfield = b'\x00' * bitfield_length
+    attestation = Attestation(
+        aggregation_bitfield=aggregation_bitfield,
+        data=attestation_data,
+        custody_bitfield=custody_bitfield,
+        aggregate_signature=EMPTY_SIGNATURE,
+    )
+    participants = get_attestation_participants(
+        state,
+        attestation.data,
+        attestation.aggregation_bitfield,
+    )
+    assert len(participants) == 1
+
+    validator_index = participants[0]
+    privkey = privkeys[validator_index]
+
+    message_hash = AttestationDataAndCustodyBit(
+        data=attestation.data,
+        custody_bit=0b0,
+    ).hash_tree_root()
+
+    attestation.aggregation_signature = bls.sign(
+        message_hash=message_hash,
+        privkey=privkey,
+        domain=get_domain(
+            fork=state.fork,
+            epoch=get_current_epoch(state),
+            domain_type=spec.DOMAIN_ATTESTATION,
+        )
+    )
+    return attestation

tests/phase0/test_sanity.py

@@ -11,19 +11,13 @@ from build.phase0.spec import (
     EMPTY_SIGNATURE,
     ZERO_HASH,
     # SSZ
-    Attestation,
-    AttestationDataAndCustodyBit,
-    BeaconBlockHeader,
     Deposit,
     Transfer,
-    ProposerSlashing,
     VoluntaryExit,
     # functions
     get_active_validator_indices,
-    get_attestation_participants,
     get_balance,
     get_block_root,
-    get_crosslink_committees_at_slot,
     get_current_epoch,
     get_domain,
     get_state_root,
@@ -42,11 +36,13 @@ from build.phase0.utils.merkle_minimal import (
     get_merkle_root,
 )
 from tests.phase0.helpers import (
-    build_attestation_data,
     build_deposit_data,
     build_empty_block_for_next_slot,
     force_registry_change_at_next_epoch,
+    get_valid_attestation,
     get_valid_proposer_slashing,
+    privkeys,
+    pubkeys,
 )
 
 
@@ -112,11 +108,13 @@ def test_empty_epoch_transition_not_finalizing(state):
 
     assert test_state.slot == block.slot
     assert test_state.finalized_epoch < get_current_epoch(test_state) - 4
+    for index in range(len(test_state.validator_registry)):
+        assert get_balance(test_state, index) < get_balance(state, index)
 
     return state, [block], test_state
 
 
-def test_proposer_slashing(state, pubkeys, privkeys):
+def test_proposer_slashing(state):
     test_state = deepcopy(state)
     proposer_slashing = get_valid_proposer_slashing(state)
     validator_index = proposer_slashing.proposer_index
@@ -142,9 +140,9 @@ def test_proposer_slashing(state, pubkeys, privkeys):
     return state, [block], test_state
 
 
-def test_deposit_in_block(state, deposit_data_leaves, pubkeys, privkeys):
+def test_deposit_in_block(state):
     pre_state = deepcopy(state)
-    test_deposit_data_leaves = deepcopy(deposit_data_leaves)
+    test_deposit_data_leaves = [ZERO_HASH] * len(pre_state.validator_registry)
 
     index = len(test_deposit_data_leaves)
     pubkey = pubkeys[index]
@@ -161,7 +159,7 @@ def test_deposit_in_block(state, deposit_data_leaves, pubkeys, privkeys):
     deposit = Deposit(
         proof=list(proof),
         index=index,
-        deposit_data=deposit_data,
+        data=deposit_data,
     )
 
     pre_state.latest_eth1_data.deposit_root = root
@@ -179,9 +177,9 @@ def test_deposit_in_block(state, deposit_data_leaves, pubkeys, privkeys):
     return pre_state, [block], post_state
 
 
-def test_deposit_top_up(state, pubkeys, privkeys, deposit_data_leaves):
+def test_deposit_top_up(state):
     pre_state = deepcopy(state)
-    test_deposit_data_leaves = deepcopy(deposit_data_leaves)
+    test_deposit_data_leaves = [ZERO_HASH] * len(pre_state.validator_registry)
 
     validator_index = 0
     amount = spec.MAX_DEPOSIT_AMOUNT // 4
@@ -200,7 +198,7 @@ def test_deposit_top_up(state, pubkeys, privkeys, deposit_data_leaves):
     deposit = Deposit(
         proof=list(proof),
         index=merkle_index,
-        deposit_data=deposit_data,
+        data=deposit_data,
     )
 
     pre_state.latest_eth1_data.deposit_root = root
@@ -218,49 +216,9 @@ def test_deposit_top_up(state, pubkeys, privkeys, deposit_data_leaves):
     return pre_state, [block], post_state
 
 
-def test_attestation(state, pubkeys, privkeys):
+def test_attestation(state):
     test_state = deepcopy(state)
-    slot = state.slot
+    attestation = get_valid_attestation(state)
-    shard = state.current_shuffling_start_shard
-    attestation_data = build_attestation_data(state, slot, shard)
-
-    crosslink_committees = get_crosslink_committees_at_slot(state, slot)
-    crosslink_committee = [committee for committee, _shard in crosslink_committees if _shard == attestation_data.shard][0]
-
-    committee_size = len(crosslink_committee)
-    bitfield_length = (committee_size + 7) // 8
-    aggregation_bitfield = b'\x01' + b'\x00' * (bitfield_length - 1)
-    custody_bitfield = b'\x00' * bitfield_length
-    attestation = Attestation(
-        aggregation_bitfield=aggregation_bitfield,
-        data=attestation_data,
-        custody_bitfield=custody_bitfield,
-        aggregate_signature=EMPTY_SIGNATURE,
-    )
-    participants = get_attestation_participants(
-        test_state,
-        attestation.data,
-        attestation.aggregation_bitfield,
-    )
-    assert len(participants) == 1
-
-    validator_index = participants[0]
-    privkey = privkeys[validator_index]
-
-    message_hash = AttestationDataAndCustodyBit(
-        data=attestation.data,
-        custody_bit=0b0,
-    ).hash_tree_root()
-
-    attestation.aggregation_signature = bls.sign(
-        message_hash=message_hash,
-        privkey=privkey,
-        domain=get_domain(
-            fork=test_state.fork,
-            epoch=get_current_epoch(test_state),
-            domain_type=spec.DOMAIN_ATTESTATION,
-        )
-    )
 
     #
     # Add to state via block transition
@@ -287,7 +245,7 @@ def test_attestation(state, pubkeys, privkeys):
     return state, [attestation_block, epoch_block], test_state
 
 
-def test_voluntary_exit(state, pubkeys, privkeys):
+def test_voluntary_exit(state):
     pre_state = deepcopy(state)
     validator_index = get_active_validator_indices(
         pre_state.validator_registry,
@@ -375,7 +333,7 @@ def test_no_exit_churn_too_long_since_change(state):
     return pre_state, [block], post_state
 
 
-def test_transfer(state, pubkeys, privkeys):
+def test_transfer(state):
     pre_state = deepcopy(state)
     current_epoch = get_current_epoch(pre_state)
     sender_index = get_active_validator_indices(pre_state.validator_registry, current_epoch)[-1]

utils/phase0/hash_function.py

@@ -1,7 +1,6 @@
-# from hashlib import sha256
+from hashlib import sha256
-from eth_utils import keccak
+# from eth_utils import keccak
 
 
-# def hash(x): return sha256(x).digest()
+def hash(x): return sha256(x).digest()
-def hash(x):
+# def hash(x):  return keccak(x)
-    return keccak(x)

utils/phase0/jsonize.py

@@ -0,0 +1,52 @@
+from .minimal_ssz import hash_tree_root
+
+
+def jsonize(value, typ, include_hash_tree_roots=False):
+    if isinstance(typ, str) and typ[:4] == 'uint':
+        return value
+    elif typ == 'bool':
+        assert value in (True, False)
+        return value
+    elif isinstance(typ, list):
+        return [jsonize(element, typ[0], include_hash_tree_roots) for element in value]
+    elif isinstance(typ, str) and typ[:4] == 'byte':
+        return '0x' + value.hex()
+    elif hasattr(typ, 'fields'):
+        ret = {}
+        for field, subtype in typ.fields.items():
+            ret[field] = jsonize(getattr(value, field), subtype, include_hash_tree_roots)
+            if include_hash_tree_roots:
+                ret[field + "_hash_tree_root"] = '0x' + hash_tree_root(getattr(value, field), subtype).hex()
+        if include_hash_tree_roots:
+            ret["hash_tree_root"] = '0x' + hash_tree_root(value, typ).hex()
+        return ret
+    else:
+        print(value, typ)
+        raise Exception("Type not recognized")
+
+
+def dejsonize(json, typ):
+    if isinstance(typ, str) and typ[:4] == 'uint':
+        return json
+    elif typ == 'bool':
+        assert json in (True, False)
+        return json
+    elif isinstance(typ, list):
+        return [dejsonize(element, typ[0]) for element in json]
+    elif isinstance(typ, str) and typ[:4] == 'byte':
+        return bytes.fromhex(json[2:])
+    elif hasattr(typ, 'fields'):
+        temp = {}
+        for field, subtype in typ.fields.items():
+            temp[field] = dejsonize(json[field], subtype)
+            if field + "_hash_tree_root" in json:
+                assert(json[field + "_hash_tree_root"][2:] == 
+                       hash_tree_root(temp[field], subtype).hex())
+        ret = typ(**temp)
+        if "hash_tree_root" in json:
+            assert(json["hash_tree_root"][2:] == 
+                   hash_tree_root(ret, typ).hex())
+        return ret
+    else:
+        print(json, typ)
+        raise Exception("Type not recognized")

utils/phase0/state_transition.py

@@ -95,7 +95,7 @@ def process_epoch_transition(state: BeaconState) -> None:
     spec.maybe_reset_eth1_period(state)
     spec.apply_rewards(state)
     spec.process_ejections(state)
-    spec.update_registry_and_shuffling_data(state)
+    spec.update_registry(state)
     spec.process_slashings(state)
     spec.process_exit_queue(state)
     spec.finish_epoch_update(state)