Make lightclient an executable patch fork

.gitignore

@@ -17,6 +17,7 @@ eth2.0-spec-tests/
 # Dynamically built from Markdown spec
 tests/core/pyspec/eth2spec/phase0/
 tests/core/pyspec/eth2spec/phase1/
+tests/core/pyspec/eth2spec/lightclient/
 
 # coverage reports
 .htmlcov

Makefile

@@ -112,7 +112,7 @@ codespell:
 lint: pyspec
 	. venv/bin/activate; cd $(PY_SPEC_DIR); \
 	flake8  --config $(LINTER_CONFIG_FILE) ./eth2spec \
-	&& mypy --config-file $(LINTER_CONFIG_FILE) -p eth2spec.phase0 -p eth2spec.phase1
+	&& mypy --config-file $(LINTER_CONFIG_FILE) -p eth2spec.phase0 -p eth2spec.phase1 -p eth2spec.lightclient
 
 lint_generators: pyspec
 	. venv/bin/activate; cd $(TEST_GENERATORS_DIR); \

setup.py

@@ -156,6 +156,40 @@ def get_spec(file_name: str) -> SpecObject:
 
 CONFIG_NAME = 'mainnet'
 '''
+LIGHTCLIENT_IMPORT = '''from eth2spec.phase0 import spec as phase0
+from eth2spec.config.config_util import apply_constants_config
+from typing import (
+    Any, Dict, Set, Sequence, NewType, Tuple, TypeVar, Callable, Optional
+)
+
+from dataclasses import (
+    dataclass,
+    field,
+)
+
+from lru import LRU
+
+from eth2spec.utils.ssz.ssz_impl import hash_tree_root, copy, uint_to_bytes
+from eth2spec.utils.ssz.ssz_typing import (
+    View, boolean, Container, List, Vector, uint8, uint32, uint64,
+    Bytes1, Bytes4, Bytes32, Bytes48, Bytes96, Bitlist,
+)
+from eth2spec.utils import bls
+
+from eth2spec.utils.hash_function import hash
+
+# Whenever lightclient is loaded, make sure we have the latest phase0
+from importlib import reload
+reload(phase0)
+
+
+SSZVariableName = str
+GeneralizedIndex = NewType('GeneralizedIndex', int)
+SSZObject = TypeVar('SSZObject', bound=View)
+
+CONFIG_NAME = 'mainnet'
+'''
+
 SUNDRY_CONSTANTS_FUNCTIONS = '''
 def ceillog2(x: int) -> uint64:
     if x < 1:
@@ -351,6 +385,7 @@ def combine_spec_objects(spec0: SpecObject, spec1: SpecObject) -> SpecObject:
 fork_imports = {
     'phase0': PHASE0_IMPORTS,
     'phase1': PHASE1_IMPORTS,
+    'lightclient': LIGHTCLIENT_IMPORT,
 }
 
 
@@ -417,6 +452,14 @@ def finalize_options(self):
                     specs/phase1/shard-fork-choice.md
                     specs/phase1/validator.md
                 """
+            elif self.spec_fork == "lightclient":
+                self.md_doc_paths = """
+                    specs/phase0/beacon-chain.md
+                    specs/phase0/fork-choice.md
+                    specs/phase0/validator.md
+                    specs/phase0/weak-subjectivity.md
+                    specs/lightclient/beacon-chain.md
+                """
             else:
                 raise Exception('no markdown files specified, and spec fork "%s" is unknown', self.spec_fork)
 

specs/lightclient/beacon-chain.md

@@ -70,15 +70,25 @@ This is a standalone beacon chain patch adding light client support via sync com
 #### `BeaconBlockBody`
 
 ```python
-class BeaconBlockBody(phase0.BeaconBlockBody):
+class BeaconBlockBody(Container):
+    randao_reveal: BLSSignature
+    eth1_data: Eth1Data  # Eth1 data vote
+    graffiti: Bytes32  # Arbitrary data
+    # Operations
+    proposer_slashings: List[ProposerSlashing, MAX_PROPOSER_SLASHINGS]
+    attester_slashings: List[AttesterSlashing, MAX_ATTESTER_SLASHINGS]
+    attestations: List[Attestation, MAX_ATTESTATIONS]
+    deposits: List[Deposit, MAX_DEPOSITS]
+    voluntary_exits: List[SignedVoluntaryExit, MAX_VOLUNTARY_EXITS]
+    # Lightclient
     sync_committee_bits: Bitlist[MAX_SYNC_COMMITTEE_SIZE]
     sync_committee_signature: BLSSignature
 ```
 
 #### `BeaconState`
 
 ```python
-class BeaconState(phase0.BeaconState):
+class BeaconState(Container):
     current_sync_committee: SyncCommittee
     next_sync_committee: SyncCommittee
 ```
@@ -133,7 +143,7 @@ def get_sync_committee_indices(state: BeaconState, epoch: Epoch) -> Sequence[Val
     start_epoch = Epoch((max(epoch // EPOCHS_PER_SYNC_COMMITTEE_PERIOD, 1) - 1) * EPOCHS_PER_SYNC_COMMITTEE_PERIOD)
     active_validator_count = uint64(len(get_active_validator_indices(state, start_epoch)))
     sync_committee_size = min(active_validator_count, MAX_SYNC_COMMITTEE_SIZE)
-    seed = get_seed(state, base_epoch, DOMAIN_SYNC_COMMITTEE)
+    seed = get_seed(state, start_epoch, DOMAIN_SYNC_COMMITTEE)
     return [compute_shuffled_index(uint64(i), active_validator_count, seed) for i in range(sync_committee_size)]
 ```
 
@@ -148,7 +158,7 @@ def get_sync_committee(state: BeaconState, epoch: Epoch) -> SyncCommittee:
     validators = [state.validators[index] for index in indices]
     pubkeys = [validator.pubkey for validator in validators]
     compact_validators = [compactify_validator(i, v.slashed, v.effective_balance) for i, v in zip(indices, validators)]
-    return SyncCommittee(pubkeys, bls.AggregatePubkeys(pubkeys), compact_validators)
+    return SyncCommittee(pubkeys, bls.AggregatePKs(pubkeys), compact_validators)
 ```
 
 ### Block processing