Merge pull request #2771 from ethereum/dev

release v1.1.7
This commit is contained in:
Hsiao-Wei Wang 2021-12-22 23:57:29 +08:00 committed by GitHub
commit 93c933c827
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16 changed files with 691 additions and 186 deletions

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@ -22,3 +22,5 @@ EPOCHS_PER_SYNC_COMMITTEE_PERIOD: 256
# ---------------------------------------------------------------
# 1
MIN_SYNC_COMMITTEE_PARTICIPANTS: 1
# SLOTS_PER_EPOCH * EPOCHS_PER_SYNC_COMMITTEE_PERIOD (= 32 * 256)
UPDATE_TIMEOUT: 8192

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@ -22,3 +22,5 @@ EPOCHS_PER_SYNC_COMMITTEE_PERIOD: 8
# ---------------------------------------------------------------
# 1
MIN_SYNC_COMMITTEE_PARTICIPANTS: 1
# SLOTS_PER_EPOCH * EPOCHS_PER_SYNC_COMMITTEE_PERIOD (= 8 * 8)
UPDATE_TIMEOUT: 64

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@ -683,6 +683,7 @@ ignored_dependencies = [
'uint8', 'uint16', 'uint32', 'uint64', 'uint128', 'uint256',
'bytes', 'byte', 'ByteList', 'ByteVector',
'Dict', 'dict', 'field', 'ceillog2', 'floorlog2', 'Set',
'Optional',
]

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@ -13,12 +13,14 @@
- [Preset](#preset)
- [Misc](#misc)
- [Containers](#containers)
- [`LightClientSnapshot`](#lightclientsnapshot)
- [`LightClientUpdate`](#lightclientupdate)
- [`LightClientStore`](#lightclientstore)
- [Helper functions](#helper-functions)
- [`get_subtree_index`](#get_subtree_index)
- [`get_active_header`](#get_active_header)
- [`get_safety_threshold`](#get_safety_threshold)
- [Light client state updates](#light-client-state-updates)
- [`process_slot_for_light_client_store`](#process_slot_for_light_client_store)
- [`validate_light_client_update`](#validate_light_client_update)
- [`apply_light_client_update`](#apply_light_client_update)
- [`process_light_client_update`](#process_light_client_update)
@ -47,38 +49,27 @@ uses sync committees introduced in [this beacon chain extension](./beacon-chain.
### Misc
| Name | Value |
| - | - |
| `MIN_SYNC_COMMITTEE_PARTICIPANTS` | `1` |
| Name | Value | Notes |
| - | - | - |
| `MIN_SYNC_COMMITTEE_PARTICIPANTS` | `1` | |
| `UPDATE_TIMEOUT` | `SLOTS_PER_EPOCH * EPOCHS_PER_SYNC_COMMITTEE_PERIOD` | ~27.3 hours |
## Containers
### `LightClientSnapshot`
```python
class LightClientSnapshot(Container):
# Beacon block header
header: BeaconBlockHeader
# Sync committees corresponding to the header
current_sync_committee: SyncCommittee
next_sync_committee: SyncCommittee
```
### `LightClientUpdate`
```python
class LightClientUpdate(Container):
# Update beacon block header
header: BeaconBlockHeader
# Next sync committee corresponding to the header
# The beacon block header that is attested to by the sync committee
attested_header: BeaconBlockHeader
# Next sync committee corresponding to the active header
next_sync_committee: SyncCommittee
next_sync_committee_branch: Vector[Bytes32, floorlog2(NEXT_SYNC_COMMITTEE_INDEX)]
# Finality proof for the update header
finality_header: BeaconBlockHeader
# The finalized beacon block header attested to by Merkle branch
finalized_header: BeaconBlockHeader
finality_branch: Vector[Bytes32, floorlog2(FINALIZED_ROOT_INDEX)]
# Sync committee aggregate signature
sync_committee_bits: Bitvector[SYNC_COMMITTEE_SIZE]
sync_committee_signature: BLSSignature
sync_committee_aggregate: SyncAggregate
# Fork version for the aggregate signature
fork_version: Version
```
@ -88,8 +79,18 @@ class LightClientUpdate(Container):
```python
@dataclass
class LightClientStore(object):
snapshot: LightClientSnapshot
valid_updates: Set[LightClientUpdate]
# Beacon block header that is finalized
finalized_header: BeaconBlockHeader
# Sync committees corresponding to the header
current_sync_committee: SyncCommittee
next_sync_committee: SyncCommittee
# Best available header to switch finalized head to if we see nothing else
best_valid_update: Optional[LightClientUpdate]
# Most recent available reasonably-safe header
optimistic_header: BeaconBlockHeader
# Max number of active participants in a sync committee (used to calculate safety threshold)
previous_max_active_participants: uint64
current_max_active_participants: uint64
```
## Helper functions
@ -101,95 +102,157 @@ def get_subtree_index(generalized_index: GeneralizedIndex) -> uint64:
return uint64(generalized_index % 2**(floorlog2(generalized_index)))
```
### `get_active_header`
```python
def get_active_header(update: LightClientUpdate) -> BeaconBlockHeader:
# The "active header" is the header that the update is trying to convince us
# to accept. If a finalized header is present, it's the finalized header,
# otherwise it's the attested header
if update.finalized_header != BeaconBlockHeader():
return update.finalized_header
else:
return update.attested_header
```
### `get_safety_threshold`
```python
def get_safety_threshold(store: LightClientStore) -> uint64:
return max(
store.previous_max_active_participants,
store.current_max_active_participants,
) // 2
```
## Light client state updates
A light client maintains its state in a `store` object of type `LightClientStore` and receives `update` objects of type `LightClientUpdate`. Every `update` triggers `process_light_client_update(store, update, current_slot)` where `current_slot` is the current slot based on some local clock.
A light client maintains its state in a `store` object of type `LightClientStore` and receives `update` objects of type `LightClientUpdate`. Every `update` triggers `process_light_client_update(store, update, current_slot)` where `current_slot` is the current slot based on some local clock. `process_slot_for_light_client_store` is processed every time the current slot increments.
#### `process_slot_for_light_client_store`
```python
def process_slot_for_light_client_store(store: LightClientStore, current_slot: Slot) -> None:
if current_slot % UPDATE_TIMEOUT == 0:
store.previous_max_active_participants = store.current_max_active_participants
store.current_max_active_participants = 0
if (
current_slot > store.finalized_header.slot + UPDATE_TIMEOUT
and store.best_valid_update is not None
):
# Forced best update when the update timeout has elapsed
apply_light_client_update(store, store.best_valid_update)
store.best_valid_update = None
```
#### `validate_light_client_update`
```python
def validate_light_client_update(snapshot: LightClientSnapshot,
def validate_light_client_update(store: LightClientStore,
update: LightClientUpdate,
current_slot: Slot,
genesis_validators_root: Root) -> None:
# Verify update slot is larger than snapshot slot
assert update.header.slot > snapshot.header.slot
# Verify update slot is larger than slot of current best finalized header
active_header = get_active_header(update)
assert current_slot >= active_header.slot > store.finalized_header.slot
# Verify update does not skip a sync committee period
snapshot_period = compute_epoch_at_slot(snapshot.header.slot) // EPOCHS_PER_SYNC_COMMITTEE_PERIOD
update_period = compute_epoch_at_slot(update.header.slot) // EPOCHS_PER_SYNC_COMMITTEE_PERIOD
assert update_period in (snapshot_period, snapshot_period + 1)
finalized_period = compute_epoch_at_slot(store.finalized_header.slot) // EPOCHS_PER_SYNC_COMMITTEE_PERIOD
update_period = compute_epoch_at_slot(active_header.slot) // EPOCHS_PER_SYNC_COMMITTEE_PERIOD
assert update_period in (finalized_period, finalized_period + 1)
# Verify update header root is the finalized root of the finality header, if specified
if update.finality_header == BeaconBlockHeader():
signed_header = update.header
# Verify that the `finalized_header`, if present, actually is the finalized header saved in the
# state of the `attested header`
if update.finalized_header == BeaconBlockHeader():
assert update.finality_branch == [Bytes32() for _ in range(floorlog2(FINALIZED_ROOT_INDEX))]
else:
signed_header = update.finality_header
assert is_valid_merkle_branch(
leaf=hash_tree_root(update.header),
leaf=hash_tree_root(update.finalized_header),
branch=update.finality_branch,
depth=floorlog2(FINALIZED_ROOT_INDEX),
index=get_subtree_index(FINALIZED_ROOT_INDEX),
root=update.finality_header.state_root,
root=update.attested_header.state_root,
)
# Verify update next sync committee if the update period incremented
if update_period == snapshot_period:
sync_committee = snapshot.current_sync_committee
if update_period == finalized_period:
sync_committee = store.current_sync_committee
assert update.next_sync_committee_branch == [Bytes32() for _ in range(floorlog2(NEXT_SYNC_COMMITTEE_INDEX))]
else:
sync_committee = snapshot.next_sync_committee
sync_committee = store.next_sync_committee
assert is_valid_merkle_branch(
leaf=hash_tree_root(update.next_sync_committee),
branch=update.next_sync_committee_branch,
depth=floorlog2(NEXT_SYNC_COMMITTEE_INDEX),
index=get_subtree_index(NEXT_SYNC_COMMITTEE_INDEX),
root=update.header.state_root,
root=active_header.state_root,
)
sync_aggregate = update.sync_committee_aggregate
# Verify sync committee has sufficient participants
assert sum(update.sync_committee_bits) >= MIN_SYNC_COMMITTEE_PARTICIPANTS
assert sum(sync_aggregate.sync_committee_bits) >= MIN_SYNC_COMMITTEE_PARTICIPANTS
# Verify sync committee aggregate signature
participant_pubkeys = [pubkey for (bit, pubkey) in zip(update.sync_committee_bits, sync_committee.pubkeys) if bit]
participant_pubkeys = [
pubkey for (bit, pubkey) in zip(sync_aggregate.sync_committee_bits, sync_committee.pubkeys)
if bit
]
domain = compute_domain(DOMAIN_SYNC_COMMITTEE, update.fork_version, genesis_validators_root)
signing_root = compute_signing_root(signed_header, domain)
assert bls.FastAggregateVerify(participant_pubkeys, signing_root, update.sync_committee_signature)
signing_root = compute_signing_root(update.attested_header, domain)
assert bls.FastAggregateVerify(participant_pubkeys, signing_root, sync_aggregate.sync_committee_signature)
```
#### `apply_light_client_update`
```python
def apply_light_client_update(snapshot: LightClientSnapshot, update: LightClientUpdate) -> None:
snapshot_period = compute_epoch_at_slot(snapshot.header.slot) // EPOCHS_PER_SYNC_COMMITTEE_PERIOD
update_period = compute_epoch_at_slot(update.header.slot) // EPOCHS_PER_SYNC_COMMITTEE_PERIOD
if update_period == snapshot_period + 1:
snapshot.current_sync_committee = snapshot.next_sync_committee
snapshot.next_sync_committee = update.next_sync_committee
snapshot.header = update.header
def apply_light_client_update(store: LightClientStore, update: LightClientUpdate) -> None:
active_header = get_active_header(update)
finalized_period = compute_epoch_at_slot(store.finalized_header.slot) // EPOCHS_PER_SYNC_COMMITTEE_PERIOD
update_period = compute_epoch_at_slot(active_header.slot) // EPOCHS_PER_SYNC_COMMITTEE_PERIOD
if update_period == finalized_period + 1:
store.current_sync_committee = store.next_sync_committee
store.next_sync_committee = update.next_sync_committee
store.finalized_header = active_header
```
#### `process_light_client_update`
```python
def process_light_client_update(store: LightClientStore, update: LightClientUpdate, current_slot: Slot,
def process_light_client_update(store: LightClientStore,
update: LightClientUpdate,
current_slot: Slot,
genesis_validators_root: Root) -> None:
validate_light_client_update(store.snapshot, update, genesis_validators_root)
store.valid_updates.add(update)
validate_light_client_update(store, update, current_slot, genesis_validators_root)
update_timeout = SLOTS_PER_EPOCH * EPOCHS_PER_SYNC_COMMITTEE_PERIOD
sync_committee_bits = update.sync_committee_aggregate.sync_committee_bits
# Update the best update in case we have to force-update to it if the timeout elapses
if (
sum(update.sync_committee_bits) * 3 >= len(update.sync_committee_bits) * 2
and update.finality_header != BeaconBlockHeader()
store.best_valid_update is None
or sum(sync_committee_bits) > sum(store.best_valid_update.sync_committee_aggregate.sync_committee_bits)
):
# Apply update if (1) 2/3 quorum is reached and (2) we have a finality proof.
# Note that (2) means that the current light client design needs finality.
# It may be changed to re-organizable light client design. See the on-going issue consensus-specs#2182.
apply_light_client_update(store.snapshot, update)
store.valid_updates = set()
elif current_slot > store.snapshot.header.slot + update_timeout:
# Forced best update when the update timeout has elapsed
apply_light_client_update(store.snapshot,
max(store.valid_updates, key=lambda update: sum(update.sync_committee_bits)))
store.valid_updates = set()
store.best_valid_update = update
# Track the maximum number of active participants in the committee signatures
store.current_max_active_participants = max(
store.current_max_active_participants,
sum(sync_committee_bits),
)
# Update the optimistic header
if (
sum(sync_committee_bits) > get_safety_threshold(store)
and update.attested_header.slot > store.optimistic_header.slot
):
store.optimistic_header = update.attested_header
# Update finalized header
if (
sum(sync_committee_bits) * 3 >= len(sync_committee_bits) * 2
and update.finalized_header != BeaconBlockHeader()
):
# Normal update through 2/3 threshold
apply_light_client_update(store, update)
store.best_valid_update = None
```

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@ -1,29 +0,0 @@
<!-- START doctoc generated TOC please keep comment here to allow auto update -->
<!-- DON'T EDIT THIS SECTION, INSTEAD RE-RUN doctoc TO UPDATE -->
**Table of Contents** *generated with [DocToc](https://github.com/thlorenz/doctoc)*
- [The Merge -- Client Settings](#the-merge----client-settings)
- [Override terminal total difficulty](#override-terminal-total-difficulty)
- [Override terminal block hash](#override-terminal-block-hash)
<!-- END doctoc generated TOC please keep comment here to allow auto update -->
# The Merge -- Client Settings
**Notice**: This document is a work-in-progress for researchers and implementers.
This document specifies configurable settings that clients must implement for the Merge.
### Override terminal total difficulty
To coordinate manual overrides to [`TERMINAL_TOTAL_DIFFICULTY`](./beacon-chain.md#Transition-settings) parameter, clients must provide `--terminal-total-difficulty-override` as a configurable setting. The value provided by this setting must take precedence over pre-configured `TERMINAL_TOTAL_DIFFICULTY` parameter. Clients should accept the setting as a decimal value (i.e., *not* hexadecimal).
Except under exceptional scenarios, this setting is not expected to be used. Sufficient warning to the user about this exceptional configurable setting should be provided.
### Override terminal block hash
To allow for transition coordination around a specific PoW block, clients must also provide `--terminal-block-hash-override` and `--terminal-block-hash-epoch-override` as configurable settings.
* The value provided by `--terminal-block-hash-override` takes precedence over the pre-configured `TERMINAL_BLOCK_HASH` parameter.
* The value provided by `--terminal-block-hash-epoch-override` takes precedence over the pre-configured `TERMINAL_BLOCK_HASH_ACTIVATION_EPOCH` parameter.
Except under exceptional scenarios, these settings are not expected to be used. Sufficient warning to the user about this exceptional configurable setting should be provided.

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@ -64,7 +64,11 @@ def notify_forkchoice_updated(self: ExecutionEngine,
```
*Note*: The call of the `notify_forkchoice_updated` function maps on the `POS_FORKCHOICE_UPDATED` event defined in the [EIP-3675](https://eips.ethereum.org/EIPS/eip-3675#definitions).
As per EIP-3675, before a post-transition block is finalized, `notify_forkchoice_updated` must be called with `finalized_block_hash = Hash32()`.
As per EIP-3675, before a post-transition block is finalized, `notify_forkchoice_updated` MUST be called with `finalized_block_hash = Hash32()`.
*Note*: Client software MUST NOT call this function until the transition conditions are met on the PoW network, i.e. there exists a block for which `is_valid_terminal_pow_block` function returns `True`.
*Note*: Client software MUST call this function to initiate the payload build process to produce the merge transition block; the `head_block_hash` parameter MUST be set to the hash of a terminal PoW block in this case.
## Helpers

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@ -181,15 +181,19 @@ def get_latest_attesting_balance(store: Store, root: Root) -> Gwei:
if (i in store.latest_messages
and get_ancestor(store, store.latest_messages[i].root, store.blocks[root].slot) == root)
))
if store.proposer_boost_root == Root():
# Return only attestation score if ``proposer_boost_root`` is not set
return attestation_score
# Calculate proposer score if ``proposer_boost_root`` is set
proposer_score = Gwei(0)
if store.proposer_boost_root != Root():
block = store.blocks[root]
if get_ancestor(store, root, block.slot) == store.proposer_boost_root:
num_validators = len(get_active_validator_indices(state, get_current_epoch(state)))
avg_balance = get_total_active_balance(state) // num_validators
committee_size = num_validators // SLOTS_PER_EPOCH
committee_weight = committee_size * avg_balance
proposer_score = (committee_weight * PROPOSER_SCORE_BOOST) // 100
# Boost is applied if ``root`` is an ancestor of ``proposer_boost_root``
if get_ancestor(store, store.proposer_boost_root, store.blocks[root].slot) == root:
num_validators = len(get_active_validator_indices(state, get_current_epoch(state)))
avg_balance = get_total_active_balance(state) // num_validators
committee_size = num_validators // SLOTS_PER_EPOCH
committee_weight = committee_size * avg_balance
proposer_score = (committee_weight * PROPOSER_SCORE_BOOST) // 100
return attestation_score + proposer_score
```
@ -263,6 +267,7 @@ def get_head(store: Store) -> Root:
if len(children) == 0:
return head
# Sort by latest attesting balance with ties broken lexicographically
# Ties broken by favoring block with lexicographically higher root
head = max(children, key=lambda root: (get_latest_attesting_balance(store, root), root))
```

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@ -101,7 +101,7 @@ The following values are (non-configurable) constants used throughout the specif
| Name | Value | Notes |
| - | - | - |
| `PRIMITIVE_ROOT_OF_UNITY` | `5` | Primitive root of unity of the BLS12_381 (inner) modulus |
| `PRIMITIVE_ROOT_OF_UNITY` | `7` | Primitive root of unity of the BLS12_381 (inner) modulus |
| `DATA_AVAILABILITY_INVERSE_CODING_RATE` | `2**1` (= 2) | Factor by which samples are extended for data availability encoding |
| `POINTS_PER_SAMPLE` | `uint64(2**3)` (= 8) | 31 * 8 = 248 bytes |
| `MODULUS` | `0x73eda753299d7d483339d80809a1d80553bda402fffe5bfeffffffff00000001` (curve order of BLS12_381) |

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@ -1 +1 @@
1.1.6
1.1.7

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@ -1,3 +1,5 @@
from copy import deepcopy
from eth2spec.test.context import (
spec_state_test,
with_presets,
@ -19,20 +21,24 @@ from eth2spec.test.helpers.sync_committee import (
from eth2spec.test.helpers.merkle import build_proof
@with_altair_and_later
@spec_state_test
def test_process_light_client_update_not_updated(spec, state):
pre_snapshot = spec.LightClientSnapshot(
header=spec.BeaconBlockHeader(),
def _initialize_light_client_store(spec, state):
return spec.LightClientStore(
finalized_header=spec.BeaconBlockHeader(),
current_sync_committee=state.current_sync_committee,
next_sync_committee=state.next_sync_committee,
)
store = spec.LightClientStore(
snapshot=pre_snapshot,
valid_updates=set(),
best_valid_update=None,
optimistic_header=spec.BeaconBlockHeader(),
previous_max_active_participants=0,
current_max_active_participants=0,
)
# Block at slot 1 doesn't increase sync committee period, so it won't update snapshot
@with_altair_and_later
@spec_state_test
def test_process_light_client_update_not_timeout(spec, state):
store = _initialize_light_client_store(spec, state)
# Block at slot 1 doesn't increase sync committee period, so it won't force update store.finalized_header
block = build_empty_block_for_next_slot(spec, state)
signed_block = state_transition_and_sign_block(spec, state, block)
block_header = spec.BeaconBlockHeader(
@ -52,6 +58,10 @@ def test_process_light_client_update_not_updated(spec, state):
block_header.slot,
committee,
)
sync_committee_aggregate = spec.SyncAggregate(
sync_committee_bits=sync_committee_bits,
sync_committee_signature=sync_committee_signature,
)
next_sync_committee_branch = [spec.Bytes32() for _ in range(spec.floorlog2(spec.NEXT_SYNC_COMMITTEE_INDEX))]
# Ensure that finality checkpoint is genesis
@ -61,40 +71,34 @@ def test_process_light_client_update_not_updated(spec, state):
finality_branch = [spec.Bytes32() for _ in range(spec.floorlog2(spec.FINALIZED_ROOT_INDEX))]
update = spec.LightClientUpdate(
header=block_header,
attested_header=block_header,
next_sync_committee=state.next_sync_committee,
next_sync_committee_branch=next_sync_committee_branch,
finality_header=finality_header,
finalized_header=finality_header,
finality_branch=finality_branch,
sync_committee_bits=sync_committee_bits,
sync_committee_signature=sync_committee_signature,
sync_committee_aggregate=sync_committee_aggregate,
fork_version=state.fork.current_version,
)
pre_store = deepcopy(store)
spec.process_light_client_update(store, update, state.slot, state.genesis_validators_root)
assert len(store.valid_updates) == 1
assert store.valid_updates.pop() == update
assert store.snapshot == pre_snapshot
assert store.current_max_active_participants > 0
assert store.optimistic_header == update.attested_header
assert store.finalized_header == pre_store.finalized_header
assert store.best_valid_update == update
@with_altair_and_later
@spec_state_test
@with_presets([MINIMAL], reason="too slow")
def test_process_light_client_update_timeout(spec, state):
pre_snapshot = spec.LightClientSnapshot(
header=spec.BeaconBlockHeader(),
current_sync_committee=state.current_sync_committee,
next_sync_committee=state.next_sync_committee,
)
store = spec.LightClientStore(
snapshot=pre_snapshot,
valid_updates=set(),
)
store = _initialize_light_client_store(spec, state)
# Forward to next sync committee period
next_slots(spec, state, spec.SLOTS_PER_EPOCH * (spec.EPOCHS_PER_SYNC_COMMITTEE_PERIOD))
snapshot_period = spec.compute_epoch_at_slot(pre_snapshot.header.slot) // spec.EPOCHS_PER_SYNC_COMMITTEE_PERIOD
next_slots(spec, state, spec.UPDATE_TIMEOUT)
snapshot_period = spec.compute_epoch_at_slot(store.optimistic_header.slot) // spec.EPOCHS_PER_SYNC_COMMITTEE_PERIOD
update_period = spec.compute_epoch_at_slot(state.slot) // spec.EPOCHS_PER_SYNC_COMMITTEE_PERIOD
assert snapshot_period + 1 == update_period
@ -119,6 +123,10 @@ def test_process_light_client_update_timeout(spec, state):
committee,
block_root=spec.Root(block_header.hash_tree_root()),
)
sync_committee_aggregate = spec.SyncAggregate(
sync_committee_bits=sync_committee_bits,
sync_committee_signature=sync_committee_signature,
)
# Sync committee is updated
next_sync_committee_branch = build_proof(state.get_backing(), spec.NEXT_SYNC_COMMITTEE_INDEX)
@ -127,36 +135,30 @@ def test_process_light_client_update_timeout(spec, state):
finality_branch = [spec.Bytes32() for _ in range(spec.floorlog2(spec.FINALIZED_ROOT_INDEX))]
update = spec.LightClientUpdate(
header=block_header,
attested_header=block_header,
next_sync_committee=state.next_sync_committee,
next_sync_committee_branch=next_sync_committee_branch,
finality_header=finality_header,
finalized_header=finality_header,
finality_branch=finality_branch,
sync_committee_bits=sync_committee_bits,
sync_committee_signature=sync_committee_signature,
sync_committee_aggregate=sync_committee_aggregate,
fork_version=state.fork.current_version,
)
pre_store = deepcopy(store)
spec.process_light_client_update(store, update, state.slot, state.genesis_validators_root)
# snapshot has been updated
assert len(store.valid_updates) == 0
assert store.snapshot.header == update.header
assert store.current_max_active_participants > 0
assert store.optimistic_header == update.attested_header
assert store.best_valid_update == update
assert store.finalized_header == pre_store.finalized_header
@with_altair_and_later
@spec_state_test
@with_presets([MINIMAL], reason="too slow")
def test_process_light_client_update_finality_updated(spec, state):
pre_snapshot = spec.LightClientSnapshot(
header=spec.BeaconBlockHeader(),
current_sync_committee=state.current_sync_committee,
next_sync_committee=state.next_sync_committee,
)
store = spec.LightClientStore(
snapshot=pre_snapshot,
valid_updates=set(),
)
store = _initialize_light_client_store(spec, state)
# Change finality
blocks = []
@ -167,7 +169,7 @@ def test_process_light_client_update_finality_updated(spec, state):
# Ensure that finality checkpoint has changed
assert state.finalized_checkpoint.epoch == 3
# Ensure that it's same period
snapshot_period = spec.compute_epoch_at_slot(pre_snapshot.header.slot) // spec.EPOCHS_PER_SYNC_COMMITTEE_PERIOD
snapshot_period = spec.compute_epoch_at_slot(store.optimistic_header.slot) // spec.EPOCHS_PER_SYNC_COMMITTEE_PERIOD
update_period = spec.compute_epoch_at_slot(state.slot) // spec.EPOCHS_PER_SYNC_COMMITTEE_PERIOD
assert snapshot_period == update_period
@ -199,20 +201,24 @@ def test_process_light_client_update_finality_updated(spec, state):
committee,
block_root=spec.Root(block_header.hash_tree_root()),
)
update = spec.LightClientUpdate(
header=finalized_block_header,
next_sync_committee=state.next_sync_committee,
next_sync_committee_branch=next_sync_committee_branch,
finality_header=block_header, # block_header is the signed header
finality_branch=finality_branch,
sync_committee_aggregate = spec.SyncAggregate(
sync_committee_bits=sync_committee_bits,
sync_committee_signature=sync_committee_signature,
)
update = spec.LightClientUpdate(
attested_header=block_header,
next_sync_committee=state.next_sync_committee,
next_sync_committee_branch=next_sync_committee_branch,
finalized_header=finalized_block_header,
finality_branch=finality_branch,
sync_committee_aggregate=sync_committee_aggregate,
fork_version=state.fork.current_version,
)
spec.process_light_client_update(store, update, state.slot, state.genesis_validators_root)
# snapshot has been updated
assert len(store.valid_updates) == 0
assert store.snapshot.header == update.header
assert store.current_max_active_participants > 0
assert store.optimistic_header == update.attested_header
assert store.finalized_header == update.finalized_header
assert store.best_valid_update is None

View File

@ -1,6 +1,7 @@
import pytest
from copy import deepcopy
from dataclasses import dataclass
import importlib
from eth_utils import encode_hex
from eth2spec.phase0 import mainnet as spec_phase0_mainnet, minimal as spec_phase0_minimal
from eth2spec.altair import mainnet as spec_altair_mainnet, minimal as spec_altair_minimal
@ -85,10 +86,9 @@ class SpecForks(TypedDict, total=False):
def _prepare_state(balances_fn: Callable[[Any], Sequence[int]], threshold_fn: Callable[[Any], int],
spec: Spec, phases: SpecForks):
phase = phases[spec.fork]
balances = balances_fn(phase)
activation_threshold = threshold_fn(phase)
state = create_genesis_state(spec=phase, validator_balances=balances,
balances = balances_fn(spec)
activation_threshold = threshold_fn(spec)
state = create_genesis_state(spec=spec, validator_balances=balances,
activation_threshold=activation_threshold)
return state
@ -464,6 +464,32 @@ def with_presets(preset_bases, reason=None):
return decorator
def _get_basic_dict(ssz_dict: Dict[str, Any]) -> Dict[str, Any]:
"""
Get dict of Python built-in types from a dict of SSZ objects.
"""
result = {}
for k, v in ssz_dict.items():
if isinstance(v, int):
value = int(v)
elif isinstance(v, bytes):
value = encode_hex(v)
else:
value = str(v)
result[k] = value
return result
def _get_copy_of_spec(spec):
fork = spec.fork
preset = spec.config.PRESET_BASE
module_path = f"eth2spec.{fork}.{preset}"
module_spec = importlib.util.find_spec(module_path)
module = importlib.util.module_from_spec(module_spec)
module_spec.loader.exec_module(module)
return module
def with_config_overrides(config_overrides):
"""
WARNING: the spec_test decorator must wrap this, to ensure the decorated test actually runs.
@ -474,20 +500,20 @@ def with_config_overrides(config_overrides):
"""
def decorator(fn):
def wrapper(*args, spec: Spec, **kw):
# remember the old config
old_config = spec.config
spec = _get_copy_of_spec(spec)
# apply our overrides to a copy of it, and apply it to the spec
tmp_config = deepcopy(old_config._asdict()) # not a private method, there are multiple
tmp_config.update(config_overrides)
config = spec.config._asdict()
config.update(config_overrides)
config_types = spec.Configuration.__annotations__
# Retain types of all config values
test_config = {k: config_types[k](v) for k, v in tmp_config.items()}
modified_config = {k: config_types[k](v) for k, v in config.items()}
# Output the config for test vectors (TODO: check config YAML encoding)
yield 'config', 'data', test_config
# To output the changed config to could be serialized with yaml test vectors,
# the dict SSZ objects have to be converted into Python built-in types.
output_config = _get_basic_dict(modified_config)
yield 'config', 'data', output_config
spec.config = spec.Configuration(**test_config)
spec.config = spec.Configuration(**modified_config)
# Run the function
out = fn(*args, spec=spec, **kw)
@ -495,10 +521,6 @@ def with_config_overrides(config_overrides):
# it's generating things, and we need to complete it before setting back the config.
if out is not None:
yield from out
# Restore the old config and apply it
spec.config = old_config
return wrapper
return decorator

View File

@ -42,6 +42,12 @@ def tick_and_add_block(spec, store, signed_block, test_steps, valid=True,
return post_state
def add_attestation(spec, store, attestation, test_steps, is_from_block=False):
spec.on_attestation(store, attestation, is_from_block=is_from_block)
yield get_attestation_file_name(attestation), attestation
test_steps.append({'attestation': get_attestation_file_name(attestation)})
def tick_and_run_on_attestation(spec, store, attestation, test_steps, is_from_block=False):
parent_block = store.blocks[attestation.data.beacon_block_root]
pre_state = store.block_states[spec.hash_tree_root(parent_block)]
@ -52,9 +58,7 @@ def tick_and_run_on_attestation(spec, store, attestation, test_steps, is_from_bl
spec.on_tick(store, next_epoch_time)
test_steps.append({'tick': int(next_epoch_time)})
spec.on_attestation(store, attestation, is_from_block=is_from_block)
yield get_attestation_file_name(attestation), attestation
test_steps.append({'attestation': get_attestation_file_name(attestation)})
yield from add_attestation(spec, store, attestation, test_steps, is_from_block)
def run_on_attestation(spec, store, attestation, is_from_block=False, valid=True):

View File

@ -0,0 +1,421 @@
from eth2spec.test.context import (
MAINNET,
spec_state_test,
with_all_phases,
with_presets,
)
from eth2spec.test.helpers.attestations import (
get_valid_attestation,
sign_attestation,
)
from eth2spec.test.helpers.block import (
build_empty_block,
)
from eth2spec.test.helpers.fork_choice import (
get_genesis_forkchoice_store_and_block,
on_tick_and_append_step,
add_attestation,
add_block,
tick_and_add_block,
)
from eth2spec.test.helpers.state import (
state_transition_and_sign_block,
)
def _apply_base_block_a(spec, state, store, test_steps):
# On receiving block A at slot `N`
block = build_empty_block(spec, state, slot=state.slot + 1)
signed_block_a = state_transition_and_sign_block(spec, state, block)
yield from tick_and_add_block(spec, store, signed_block_a, test_steps)
assert spec.get_head(store) == signed_block_a.message.hash_tree_root()
@with_all_phases
@spec_state_test
def test_ex_ante_vanilla(spec, state):
"""
With a single adversarial attestation
Objects:
Block A - slot N
Block B (parent A) - slot N+1
Block C (parent A) - slot N+2
Attestation_1 (Block B); size `1` - slot N+1
Steps:
Block A received at N A is head
Block C received at N+2 C is head
Block B received at N+2 C is head
Attestation_1 received at N+2 C is head
"""
test_steps = []
# Initialization
store, anchor_block = get_genesis_forkchoice_store_and_block(spec, state)
yield 'anchor_state', state
yield 'anchor_block', anchor_block
current_time = state.slot * spec.config.SECONDS_PER_SLOT + store.genesis_time
on_tick_and_append_step(spec, store, current_time, test_steps)
assert store.time == current_time
# On receiving block A at slot `N`
yield from _apply_base_block_a(spec, state, store, test_steps)
state_a = state.copy()
# Block B at slot `N + 1`, parent is A
state_b = state_a.copy()
block = build_empty_block(spec, state_a, slot=state_a.slot + 1)
signed_block_b = state_transition_and_sign_block(spec, state_b, block)
# Block C at slot `N + 2`, parent is A
state_c = state_a.copy()
block = build_empty_block(spec, state_c, slot=state_a.slot + 2)
signed_block_c = state_transition_and_sign_block(spec, state_c, block)
# Attestation_1 at slot `N + 1` voting for block B
def _filter_participant_set(participants):
return [next(iter(participants))]
attestation = get_valid_attestation(
spec, state_b, slot=state_b.slot, signed=False, filter_participant_set=_filter_participant_set
)
attestation.data.beacon_block_root = signed_block_b.message.hash_tree_root()
assert len([i for i in attestation.aggregation_bits if i == 1]) == 1
sign_attestation(spec, state_b, attestation)
# Block C received at N+2 — C is head
time = state_c.slot * spec.config.SECONDS_PER_SLOT + store.genesis_time
on_tick_and_append_step(spec, store, time, test_steps)
yield from add_block(spec, store, signed_block_c, test_steps)
assert spec.get_head(store) == signed_block_c.message.hash_tree_root()
# Block B received at N+2 — C is head due to proposer score boost
yield from add_block(spec, store, signed_block_b, test_steps)
assert spec.get_head(store) == signed_block_c.message.hash_tree_root()
# Attestation_1 received at N+2 — C is head
yield from add_attestation(spec, store, attestation, test_steps)
assert spec.get_head(store) == signed_block_c.message.hash_tree_root()
yield 'steps', test_steps
def _get_greater_than_proposer_boost_score(spec, store, state, proposer_boost_root, root):
"""
Return the minimum attestation participant count such that attestation_score > proposer_score
"""
# calculate proposer boost score
block = store.blocks[root]
proposer_score = 0
if spec.get_ancestor(store, root, block.slot) == proposer_boost_root:
num_validators = len(spec.get_active_validator_indices(state, spec.get_current_epoch(state)))
avg_balance = spec.get_total_active_balance(state) // num_validators
committee_size = num_validators // spec.SLOTS_PER_EPOCH
committee_weight = committee_size * avg_balance
proposer_score = (committee_weight * spec.config.PROPOSER_SCORE_BOOST) // 100
# calculate minimum participant count such that attestation_score > proposer_score
base_effective_balance = state.validators[0].effective_balance
return proposer_score // base_effective_balance + 1
@with_all_phases
@with_presets([MAINNET], reason="to create non-duplicate committee")
@spec_state_test
def test_ex_ante_attestations_is_greater_than_proposer_boost_with_boost(spec, state):
"""
Adversarial attestations > proposer boost
Objects:
Block A - slot N
Block B (parent A) - slot N+1
Block C (parent A) - slot N+2
Attestation_set_1 (Block B); size `proposer_boost + 1` - slot N+1
Steps:
Block A received at N A is head
Block C received at N+2 C is head
Block B received at N+2 C is head
Attestation_1 received at N+2 B is head
"""
test_steps = []
# Initialization
store, anchor_block = get_genesis_forkchoice_store_and_block(spec, state)
yield 'anchor_state', state
yield 'anchor_block', anchor_block
current_time = state.slot * spec.config.SECONDS_PER_SLOT + store.genesis_time
on_tick_and_append_step(spec, store, current_time, test_steps)
assert store.time == current_time
# On receiving block A at slot `N`
yield from _apply_base_block_a(spec, state, store, test_steps)
state_a = state.copy()
# Block B at slot `N + 1`, parent is A
state_b = state_a.copy()
block = build_empty_block(spec, state_a, slot=state_a.slot + 1)
signed_block_b = state_transition_and_sign_block(spec, state_b, block)
# Block C at slot `N + 2`, parent is A
state_c = state_a.copy()
block = build_empty_block(spec, state_c, slot=state_a.slot + 2)
signed_block_c = state_transition_and_sign_block(spec, state_c, block)
# Block C received at N+2 — C is head
time = state_c.slot * spec.config.SECONDS_PER_SLOT + store.genesis_time
on_tick_and_append_step(spec, store, time, test_steps)
yield from add_block(spec, store, signed_block_c, test_steps)
assert spec.get_head(store) == signed_block_c.message.hash_tree_root()
# Block B received at N+2 — C is head due to proposer score boost
yield from add_block(spec, store, signed_block_b, test_steps)
assert spec.get_head(store) == signed_block_c.message.hash_tree_root()
# Attestation_set_1 at slot `N + 1` voting for block B
proposer_boost_root = signed_block_b.message.hash_tree_root()
root = signed_block_b.message.hash_tree_root()
participant_num = _get_greater_than_proposer_boost_score(spec, store, state, proposer_boost_root, root)
def _filter_participant_set(participants):
return [index for i, index in enumerate(participants) if i < participant_num]
attestation = get_valid_attestation(
spec, state_b, slot=state_b.slot, signed=False, filter_participant_set=_filter_participant_set
)
attestation.data.beacon_block_root = signed_block_b.message.hash_tree_root()
assert len([i for i in attestation.aggregation_bits if i == 1]) == participant_num
sign_attestation(spec, state_b, attestation)
# Attestation_set_1 received at N+2 — B is head because B's attestation_score > C's proposer_score.
# (B's proposer_score = C's attestation_score = 0)
yield from add_attestation(spec, store, attestation, test_steps)
assert spec.get_head(store) == signed_block_b.message.hash_tree_root()
yield 'steps', test_steps
@with_all_phases
@spec_state_test
def test_ex_ante_sandwich_without_attestations(spec, state):
"""
Simple Sandwich test with boost and no attestations.
Obejcts:
Block A - slot N
Block B (parent A) - slot N+1
Block C (parent A) - slot N+2
Block D (parent B) - slot N+3
Steps:
Block A received at N A is head
Block C received at N+2 C is head
Block B received at N+2 C is head (with boost)
Block D received at N+3 D is head (with boost)
"""
test_steps = []
# Initialization
store, anchor_block = get_genesis_forkchoice_store_and_block(spec, state)
yield 'anchor_state', state
yield 'anchor_block', anchor_block
current_time = state.slot * spec.config.SECONDS_PER_SLOT + store.genesis_time
on_tick_and_append_step(spec, store, current_time, test_steps)
assert store.time == current_time
# On receiving block A at slot `N`
yield from _apply_base_block_a(spec, state, store, test_steps)
state_a = state.copy()
# Block B at slot `N + 1`, parent is A
state_b = state_a.copy()
block = build_empty_block(spec, state_a, slot=state_a.slot + 1)
signed_block_b = state_transition_and_sign_block(spec, state_b, block)
# Block C at slot `N + 2`, parent is A
state_c = state_a.copy()
block = build_empty_block(spec, state_c, slot=state_a.slot + 2)
signed_block_c = state_transition_and_sign_block(spec, state_c, block)
# Block D at slot `N + 3`, parent is B
state_d = state_b.copy()
block = build_empty_block(spec, state_d, slot=state_a.slot + 3)
signed_block_d = state_transition_and_sign_block(spec, state_d, block)
# Block C received at N+2 — C is head
time = state_c.slot * spec.config.SECONDS_PER_SLOT + store.genesis_time
on_tick_and_append_step(spec, store, time, test_steps)
yield from add_block(spec, store, signed_block_c, test_steps)
assert spec.get_head(store) == signed_block_c.message.hash_tree_root()
# Block B received at N+2 — C is head, it has proposer score boost
yield from add_block(spec, store, signed_block_b, test_steps)
assert spec.get_head(store) == signed_block_c.message.hash_tree_root()
# Block D received at N+3 - D is head, it has proposer score boost
time = state_d.slot * spec.config.SECONDS_PER_SLOT + store.genesis_time
on_tick_and_append_step(spec, store, time, test_steps)
yield from add_block(spec, store, signed_block_d, test_steps)
assert spec.get_head(store) == signed_block_d.message.hash_tree_root()
yield 'steps', test_steps
@with_all_phases
@spec_state_test
def test_ex_ante_sandwich_with_honest_attestation(spec, state):
"""
Boosting necessary to sandwich attack.
Objects:
Block A - slot N
Block B (parent A) - slot N+1
Block C (parent A) - slot N+2
Block D (parent B) - slot N+3
Attestation_1 (Block C); size 1 - slot N+2 (honest)
Steps:
Block A received at N A is head
Block C received at N+2 C is head
Block B received at N+2 C is head
Attestation_1 received at N+3 C is head
Block D received at N+3 D is head
"""
test_steps = []
# Initialization
store, anchor_block = get_genesis_forkchoice_store_and_block(spec, state)
yield 'anchor_state', state
yield 'anchor_block', anchor_block
current_time = state.slot * spec.config.SECONDS_PER_SLOT + store.genesis_time
on_tick_and_append_step(spec, store, current_time, test_steps)
assert store.time == current_time
# On receiving block A at slot `N`
yield from _apply_base_block_a(spec, state, store, test_steps)
state_a = state.copy()
# Block B at slot `N + 1`, parent is A
state_b = state_a.copy()
block = build_empty_block(spec, state_a, slot=state_a.slot + 1)
signed_block_b = state_transition_and_sign_block(spec, state_b, block)
# Block C at slot `N + 2`, parent is A
state_c = state_a.copy()
block = build_empty_block(spec, state_c, slot=state_a.slot + 2)
signed_block_c = state_transition_and_sign_block(spec, state_c, block)
# Attestation_1 at N+2 voting for block C
def _filter_participant_set(participants):
return [next(iter(participants))]
attestation = get_valid_attestation(
spec, state_c, slot=state_c.slot, signed=False, filter_participant_set=_filter_participant_set
)
attestation.data.beacon_block_root = signed_block_c.message.hash_tree_root()
assert len([i for i in attestation.aggregation_bits if i == 1]) == 1
sign_attestation(spec, state_c, attestation)
# Block D at slot `N + 3`, parent is B
state_d = state_b.copy()
block = build_empty_block(spec, state_d, slot=state_a.slot + 3)
signed_block_d = state_transition_and_sign_block(spec, state_d, block)
# Block C received at N+2 — C is head
time = state_c.slot * spec.config.SECONDS_PER_SLOT + store.genesis_time
on_tick_and_append_step(spec, store, time, test_steps)
yield from add_block(spec, store, signed_block_c, test_steps)
assert spec.get_head(store) == signed_block_c.message.hash_tree_root()
# Block B received at N+2 — C is head, it has proposer score boost
yield from add_block(spec, store, signed_block_b, test_steps)
assert spec.get_head(store) == signed_block_c.message.hash_tree_root()
# Attestation_1 received at N+3 — C is head
time = state_d.slot * spec.config.SECONDS_PER_SLOT + store.genesis_time
on_tick_and_append_step(spec, store, time, test_steps)
yield from add_attestation(spec, store, attestation, test_steps)
assert spec.get_head(store) == signed_block_c.message.hash_tree_root()
# Block D received at N+3 - D is head, it has proposer score boost
yield from add_block(spec, store, signed_block_d, test_steps)
assert spec.get_head(store) == signed_block_d.message.hash_tree_root()
yield 'steps', test_steps
@with_all_phases
@with_presets([MAINNET], reason="to create non-duplicate committee")
@spec_state_test
def test_ex_ante_sandwich_with_boost_not_sufficient(spec, state):
"""
Boost not sufficient to sandwich attack.
Objects:
Block A - slot N
Block B (parent A) - slot N+1
Block C (parent A) - slot N+2
Block D (parent B) - slot N+3
Attestation_set_1 (Block C); size proposer_boost + 1 - slot N+2
Steps:
Block A received at N A is head
Block C received at N+2 C is head
Block B received at N+2 C is head
Attestation_set_1 received C is head
Block D received at N+3 C is head
"""
test_steps = []
# Initialization
store, anchor_block = get_genesis_forkchoice_store_and_block(spec, state)
yield 'anchor_state', state
yield 'anchor_block', anchor_block
current_time = state.slot * spec.config.SECONDS_PER_SLOT + store.genesis_time
on_tick_and_append_step(spec, store, current_time, test_steps)
assert store.time == current_time
# On receiving block A at slot `N`
yield from _apply_base_block_a(spec, state, store, test_steps)
state_a = state.copy()
# Block B at slot `N + 1`, parent is A
state_b = state_a.copy()
block = build_empty_block(spec, state_a, slot=state_a.slot + 1)
signed_block_b = state_transition_and_sign_block(spec, state_b, block)
# Block C at slot `N + 2`, parent is A
state_c = state_a.copy()
block = build_empty_block(spec, state_c, slot=state_a.slot + 2)
signed_block_c = state_transition_and_sign_block(spec, state_c, block)
# Block D at slot `N + 3`, parent is B
state_d = state_b.copy()
block = build_empty_block(spec, state_d, slot=state_a.slot + 3)
signed_block_d = state_transition_and_sign_block(spec, state_d, block)
# Block C received at N+2 — C is head
time = state_c.slot * spec.config.SECONDS_PER_SLOT + store.genesis_time
on_tick_and_append_step(spec, store, time, test_steps)
yield from add_block(spec, store, signed_block_c, test_steps)
assert spec.get_head(store) == signed_block_c.message.hash_tree_root()
# Block B received at N+2 — C is head, it has proposer score boost
yield from add_block(spec, store, signed_block_b, test_steps)
assert spec.get_head(store) == signed_block_c.message.hash_tree_root()
# Attestation_set_1 at N+2 voting for block C
proposer_boost_root = signed_block_c.message.hash_tree_root()
root = signed_block_c.message.hash_tree_root()
participant_num = _get_greater_than_proposer_boost_score(spec, store, state, proposer_boost_root, root)
def _filter_participant_set(participants):
return [index for i, index in enumerate(participants) if i < participant_num]
attestation = get_valid_attestation(
spec, state_c, slot=state_c.slot, signed=False, filter_participant_set=_filter_participant_set
)
attestation.data.beacon_block_root = signed_block_c.message.hash_tree_root()
assert len([i for i in attestation.aggregation_bits if i == 1]) == participant_num
sign_attestation(spec, state_c, attestation)
# Attestation_1 received at N+3 — B is head because B's attestation_score > C's proposer_score.
# (B's proposer_score = C's attestation_score = 0)
time = state_d.slot * spec.config.SECONDS_PER_SLOT + store.genesis_time
on_tick_and_append_step(spec, store, time, test_steps)
yield from add_attestation(spec, store, attestation, test_steps)
assert spec.get_head(store) == signed_block_c.message.hash_tree_root()
# Block D received at N+3 - C is head, D's boost not sufficient!
yield from add_block(spec, store, signed_block_d, test_steps)
assert spec.get_head(store) == signed_block_c.message.hash_tree_root()
yield 'steps', test_steps

View File

@ -166,6 +166,9 @@ def test_shorter_chain_but_heavier_weight(spec, state):
signed_short_block = state_transition_and_sign_block(spec, short_state, short_block)
yield from tick_and_add_block(spec, store, signed_short_block, test_steps)
# Since the long chain has higher proposer_score at slot 1, the latest long block is the head
assert spec.get_head(store) == spec.hash_tree_root(long_block)
short_attestation = get_valid_attestation(spec, short_state, short_block.slot, signed=True)
yield from tick_and_run_on_attestation(spec, store, short_attestation, test_steps)

View File

@ -6,6 +6,7 @@ if __name__ == "__main__":
phase_0_mods = {key: 'eth2spec.test.phase0.fork_choice.test_' + key for key in [
'get_head',
'on_block',
'ex_ante',
]}
# No additional Altair specific finality tests, yet.
altair_mods = phase_0_mods

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@ -106,13 +106,13 @@ def invalid_cases():
RandomizationMode.mode_max_count]:
if len(offsets) != 0:
for offset_index in offsets:
yield f'{name}_offset_{offset_index}_plus_one', \
yield f'{name}_{mode.to_name()}_offset_{offset_index}_plus_one', \
invalid_test_case(lambda: mod_offset(
b=serialize(container_case_fn(rng, mode, typ)),
offset_index=offset_index,
change=lambda x: x + 1
))
yield f'{name}_offset_{offset_index}_zeroed', \
yield f'{name}_{mode.to_name()}_offset_{offset_index}_zeroed', \
invalid_test_case(lambda: mod_offset(
b=serialize(container_case_fn(rng, mode, typ)),
offset_index=offset_index,