add sanity check test for process_attestations

Author: djrtwo

eth/beacon/helpers.py

@@ -84,7 +84,7 @@ def get_block_root(
     """
     Returns the block root at a recent ``slot``.
     """
-    slot_relative_position = current_slot - len(latest_block_roots)
+    slot_relative_position = max(current_slot - len(latest_block_roots), 0)
     return _get_element_from_recent_list(
         latest_block_roots,
         slot,
@@ -109,7 +109,7 @@ def _get_shard_committees_at_slot(
             )
         )
 
-    slot_relative_position = state_slot - epoch_length
+    slot_relative_position = max(state_slot - epoch_length, 0)
 
     yield from _get_element_from_recent_list(
         shard_committees_at_slots,

eth/beacon/state_machines/base.py

@@ -12,7 +12,6 @@
 )
 
 from eth.beacon.db.chain import BaseBeaconChainDB
-from eth.beacon.types.attestations import Attestation
 from eth.beacon.types.blocks import BaseBeaconBlock
 from eth.beacon.types.states import BeaconState
 
@@ -64,15 +63,6 @@ def state_transition(self) -> BaseStateTransition:
     def import_block(self, block: BaseBeaconBlock) -> Tuple[BeaconState, BaseBeaconBlock]:
         pass
 
-    #
-    # State transition
-    #
-    @abstractmethod
-    def validate_attestation(self,
-                             attestation: Attestation,
-                             is_validating_signatures: bool=True) -> None:
-        raise NotImplementedError
-
 
 class BeaconStateMachine(BaseBeaconStateMachine):
     def __init__(self,

eth/beacon/state_machines/forks/serenity/__init__.py

@@ -1,6 +1,5 @@
 from typing import Type  # noqa: F401
 
-from eth.beacon.types.attestations import Attestation
 from eth.beacon.types.blocks import BaseBeaconBlock  # noqa: F401
 from eth.beacon.types.states import BeaconState  # noqa: F401
 
@@ -11,7 +10,6 @@
 from .blocks import SerenityBeaconBlock
 from .states import SerenityBeaconState
 from .state_transitions import SerenityStateTransition
-from .validation import validate_serenity_attestation
 
 
 class SerenityStateMachine(BeaconStateMachine):
@@ -23,14 +21,3 @@ class SerenityStateMachine(BeaconStateMachine):
     state_class = SerenityBeaconState  # type: Type[BeaconState]
     state_transition_class = SerenityStateTransition  # type: Type[BaseStateTransition]
     config = SERENITY_CONFIG
-
-    def validate_attestation(self,
-                             attestation: Attestation,
-                             is_validating_signatures: bool=True) -> None:
-        validate_serenity_attestation(
-            self.state,
-            attestation,
-            self.config.EPOCH_LENGTH,
-            self.config.MIN_ATTESTATION_INCLUSION_DELAY,
-            is_validating_signatures,
-        )

eth/beacon/state_machines/forks/serenity/operations.py

@@ -1,14 +1,46 @@
 from eth.beacon.types.blocks import BaseBeaconBlock
+from eth.beacon.types.pending_attestation_records import PendingAttestationRecord
 from eth.beacon.types.states import BeaconState
 from eth.beacon.state_machines.configs import BeaconConfig
 
+from .validation import (
+    validate_serenity_attestation,
+)
+
 
 def process_attestations(state: BeaconState,
                          block: BaseBeaconBlock,
-                         config: BeaconConfig) -> BeaconState:
-    # TODO
-    # It's just for demo!!!
+                         config: BeaconConfig,
+                         is_validating_signatures: bool=True) -> BeaconState:
+    """
+    Implements 'per-block-processing.operations.attestations' portion of Phase 0 spec:
+    https://github.com/ethereum/eth2.0-specs/blob/master/specs/core/0_beacon-chain.md#attestations-1
+
+    Validate the ``attestations`` contained within the ``block`` in the context of ``state``.
+    If any invalid, throw ``ValidationError``.
+    Otherwise, append an ``PendingAttestationRecords`` for each to ``latest_attestations``.
+    Return resulting ``state``.
+    """
+    for attestation in block.body.attestations:
+        validate_serenity_attestation(
+            state,
+            attestation,
+            config.EPOCH_LENGTH,
+            config.MIN_ATTESTATION_INCLUSION_DELAY,
+            is_validating_signatures,
+        )
+
+    # update_latest_attestations
+    additional_pending_attestations = tuple(
+        PendingAttestationRecord(
+            data=attestation.data,
+            participation_bitfield=attestation.participation_bitfield,
+            custody_bitfield=attestation.custody_bitfield,
+            slot_included=state.slot,
+        )
+        for attestation in block.body.attestations
+    )
     state = state.copy(
-        slot=config.ZERO_BALANCE_VALIDATOR_TTL,
+        latest_attestations=state.latest_attestations + additional_pending_attestations
     )
     return state

eth/beacon/state_machines/state_transitions.py

@@ -7,6 +7,7 @@
     Configurable,
 )
 
+from eth.beacon.types.attestations import Attestation
 from eth.beacon.types.blocks import BaseBeaconBlock
 from eth.beacon.types.states import BeaconState
 
@@ -34,3 +35,12 @@ def per_block_transition(self, state: BeaconState, block: BaseBeaconBlock) -> Be
     @abstractmethod
     def per_epoch_transition(self, state: BeaconState, block: BaseBeaconBlock) -> BeaconState:
         pass
+
+    #
+    # Operation validations
+    #
+    @abstractmethod
+    def validate_attestation(self,
+                             attestation: Attestation,
+                             is_validating_signatures: bool=True) -> None:
+        raise NotImplementedError

tests/beacon/conftest.py

@@ -1,12 +1,26 @@
 import pytest
+import rlp
 
 from eth_utils import denoms
 
 from eth.constants import (
     ZERO_HASH32,
 )
+
 import eth._utils.bls as bls
 from eth.beacon._utils.hash import hash_eth2
+from eth._utils.bitfield import (
+    get_empty_bitfield,
+)
+from eth.beacon.aggregation import (
+    aggregate_votes,
+)
+from eth.beacon.enums import (
+    SignatureDomain,
+)
+from eth.beacon.helpers import (
+    get_domain,
+)
 
 from eth.beacon.helpers import (
     get_new_shuffling,
@@ -20,11 +34,10 @@
     SlashableVoteData,
 )
 
-from eth.beacon.types.attestation_data import (
-    AttestationData,
-)
-
+from eth.beacon.types.attestation_data import AttestationData
+from eth.beacon.types.attestations import Attestation
 from eth.beacon.types.states import BeaconState
+from eth.beacon.types.crosslink_records import CrosslinkRecord
 from eth.beacon.types.deposits import DepositData
 from eth.beacon.types.deposit_input import DepositInput
 
@@ -498,7 +511,9 @@ def genesis_state(sample_beacon_state_params,
                   genesis_validators,
                   epoch_length,
                   target_committee_size,
-                  shard_count):
+                  initial_slot_number,
+                  shard_count,
+                  latest_block_roots_length):
     initial_shuffling = get_new_shuffling(
         seed=ZERO_HASH32,
         validators=genesis_validators,
@@ -511,6 +526,14 @@ def genesis_state(sample_beacon_state_params,
     return BeaconState(**sample_beacon_state_params).copy(
         validator_registry=genesis_validators,
         shard_committees_at_slots=initial_shuffling + initial_shuffling,
+        latest_block_roots=tuple(ZERO_HASH32 for _ in range(latest_block_roots_length)),
+        latest_crosslinks=tuple(
+            CrosslinkRecord(
+                slot=initial_slot_number,
+                shard_block_root=ZERO_HASH32,
+            )
+            for _ in range(shard_count)
+        )
     )
 
 
@@ -530,3 +553,50 @@ def genesis_validators(init_validator_keys,
             exit_count=0,
         ) for pub in init_validator_keys
     )
+
+
+#
+# Create mock consensus objects
+#
+@pytest.fixture
+def create_mock_signed_attestation(privkeys):
+    def create_mock_signed_attestation(state,
+                                       shard_committee,
+                                       voting_committee_indices,
+                                       attestation_data):
+        message = hash_eth2(
+            rlp.encode(attestation_data) +
+            (0).to_bytes(1, "big")
+        )
+        # participants sign message
+        signatures = [
+            bls.sign(
+                message,
+                privkeys[shard_committee.committee[committee_index]],
+                domain=get_domain(
+                    fork_data=state.fork_data,
+                    slot=attestation_data.slot,
+                    domain_type=SignatureDomain.DOMAIN_ATTESTATION,
+                )
+            )
+            for committee_index in voting_committee_indices
+        ]
+
+        # aggregate signatures and construct participant bitfield
+        participation_bitfield, aggregate_signature = aggregate_votes(
+            bitfield=get_empty_bitfield(len(shard_committee.committee)),
+            sigs=(),
+            voting_sigs=signatures,
+            voting_committee_indices=voting_committee_indices,
+        )
+
+        # create attestation from attestation_data, particpipant_bitfield, and signature
+        return Attestation(
+            data=attestation_data,
+            participation_bitfield=participation_bitfield,
+            custody_bitfield=b'',
+            aggregate_signature=aggregate_signature,
+        )
+
+    return create_mock_signed_attestation
+

tests/beacon/state_machines/test_attestation_validation.py

@@ -9,28 +9,10 @@
     ValidationError,
 )
 
-import rlp
-
 from eth.constants import (
     ZERO_HASH32,
 )
 
-from eth._utils import bls
-from eth._utils.bitfield import (
-    get_empty_bitfield,
-)
-from eth.beacon._utils.hash import (
-    hash_eth2,
-)
-from eth.beacon.aggregation import (
-    aggregate_votes,
-)
-from eth.beacon.enums import (
-    SignatureDomain,
-)
-from eth.beacon.helpers import (
-    get_domain,
-)
 from eth.beacon.state_machines.forks.serenity.validation import (
     validate_serenity_attestation_aggregate_signature,
     validate_serenity_attestation_latest_crosslink_root,
@@ -39,50 +21,9 @@
     validate_serenity_attestation_shard_block_root,
     validate_serenity_attestation_slot,
 )
-from eth.beacon.types.attestations import Attestation
 from eth.beacon.types.attestation_data import AttestationData
 
 
-def create_mock_signed_attestation(state,
-                                   shard_committee,
-                                   voting_committee_indices,
-                                   attestation_data,
-                                   privkeys):
-    message = hash_eth2(
-        rlp.encode(attestation_data) +
-        (0).to_bytes(1, "big")
-    )
-    # participants sign message
-    signatures = [
-        bls.sign(
-            message,
-            privkeys[shard_committee.committee[committee_index]],
-            domain=get_domain(
-                fork_data=state.fork_data,
-                slot=attestation_data.slot,
-                domain_type=SignatureDomain.DOMAIN_ATTESTATION,
-            )
-        )
-        for committee_index in voting_committee_indices
-    ]
-
-    # aggregate signatures and construct participant bitfield
-    participation_bitfield, aggregate_signature = aggregate_votes(
-        bitfield=get_empty_bitfield(len(shard_committee.committee)),
-        sigs=(),
-        voting_sigs=signatures,
-        voting_committee_indices=voting_committee_indices,
-    )
-
-    # create attestation from attestation_data, particpipant_bitfield, and signature
-    return Attestation(
-        data=attestation_data,
-        participation_bitfield=participation_bitfield,
-        custody_bitfield=b'',
-        aggregate_signature=aggregate_signature,
-    )
-
-
 @pytest.mark.parametrize(
     (
         'attestation_slot,'
@@ -301,8 +242,9 @@ def test_validate_serenity_attestation_shard_block_root(sample_attestation_data_
 def test_validate_serenity_attestation_aggregate_signature(genesis_state,
                                                            epoch_length,
                                                            random,
-                                                           privkeys,
                                                            sample_attestation_data_params,
+                                                           create_mock_signed_attestation,
+                                                           config,
                                                            is_valid):
     state = genesis_state
 
@@ -326,7 +268,6 @@ def test_validate_serenity_attestation_aggregate_signature(genesis_state,
         shard_committee,
         voting_committee_indices,
         attestation_data,
-        privkeys,
     )
 
     if is_valid: