200 lines
7.4 KiB
Python
200 lines
7.4 KiB
Python
from copy import deepcopy
|
|
|
|
import eth2spec.phase0.spec as spec
|
|
|
|
from eth2spec.phase0.state_transition import (
|
|
state_transition,
|
|
)
|
|
from .helpers import (
|
|
build_empty_block_for_next_slot,
|
|
fill_aggregate_attestation,
|
|
get_current_epoch,
|
|
get_epoch_start_slot,
|
|
get_valid_attestation,
|
|
next_epoch,
|
|
)
|
|
|
|
from .context import spec_state_test
|
|
|
|
|
|
def check_finality(state,
|
|
prev_state,
|
|
current_justified_changed,
|
|
previous_justified_changed,
|
|
finalized_changed):
|
|
if current_justified_changed:
|
|
assert state.current_justified_epoch > prev_state.current_justified_epoch
|
|
assert state.current_justified_root != prev_state.current_justified_root
|
|
else:
|
|
assert state.current_justified_epoch == prev_state.current_justified_epoch
|
|
assert state.current_justified_root == prev_state.current_justified_root
|
|
|
|
if previous_justified_changed:
|
|
assert state.previous_justified_epoch > prev_state.previous_justified_epoch
|
|
assert state.previous_justified_root != prev_state.previous_justified_root
|
|
else:
|
|
assert state.previous_justified_epoch == prev_state.previous_justified_epoch
|
|
assert state.previous_justified_root == prev_state.previous_justified_root
|
|
|
|
if finalized_changed:
|
|
assert state.finalized_epoch > prev_state.finalized_epoch
|
|
assert state.finalized_root != prev_state.finalized_root
|
|
else:
|
|
assert state.finalized_epoch == prev_state.finalized_epoch
|
|
assert state.finalized_root == prev_state.finalized_root
|
|
|
|
|
|
def next_epoch_with_attestations(state,
|
|
fill_cur_epoch,
|
|
fill_prev_epoch):
|
|
post_state = deepcopy(state)
|
|
blocks = []
|
|
for _ in range(spec.SLOTS_PER_EPOCH):
|
|
block = build_empty_block_for_next_slot(post_state)
|
|
if fill_cur_epoch:
|
|
slot_to_attest = post_state.slot - spec.MIN_ATTESTATION_INCLUSION_DELAY + 1
|
|
if slot_to_attest >= get_epoch_start_slot(get_current_epoch(post_state)):
|
|
cur_attestation = get_valid_attestation(post_state, slot_to_attest)
|
|
fill_aggregate_attestation(post_state, cur_attestation)
|
|
block.body.attestations.append(cur_attestation)
|
|
|
|
if fill_prev_epoch:
|
|
slot_to_attest = post_state.slot - spec.SLOTS_PER_EPOCH + 1
|
|
prev_attestation = get_valid_attestation(post_state, slot_to_attest)
|
|
fill_aggregate_attestation(post_state, prev_attestation)
|
|
block.body.attestations.append(prev_attestation)
|
|
|
|
state_transition(post_state, block)
|
|
blocks.append(block)
|
|
|
|
return state, blocks, post_state
|
|
|
|
|
|
@spec_state_test
|
|
def test_finality_rule_4(state):
|
|
yield 'pre', state
|
|
|
|
blocks = []
|
|
for epoch in range(4):
|
|
prev_state, new_blocks, state = next_epoch_with_attestations(state, True, False)
|
|
blocks += new_blocks
|
|
|
|
# justification/finalization skipped at GENESIS_EPOCH
|
|
if epoch == 0:
|
|
check_finality(state, prev_state, False, False, False)
|
|
# justification/finalization skipped at GENESIS_EPOCH + 1
|
|
elif epoch == 1:
|
|
check_finality(state, prev_state, False, False, False)
|
|
elif epoch == 2:
|
|
check_finality(state, prev_state, True, False, False)
|
|
elif epoch >= 3:
|
|
# rule 4 of finality
|
|
check_finality(state, prev_state, True, True, True)
|
|
assert state.finalized_epoch == prev_state.current_justified_epoch
|
|
assert state.finalized_root == prev_state.current_justified_root
|
|
|
|
yield 'blocks', blocks, [spec.BeaconBlock]
|
|
yield 'post', state
|
|
|
|
|
|
@spec_state_test
|
|
def test_finality_rule_1(state):
|
|
# get past first two epochs that finality does not run on
|
|
next_epoch(state)
|
|
next_epoch(state)
|
|
|
|
yield 'pre', state
|
|
|
|
blocks = []
|
|
for epoch in range(3):
|
|
prev_state, new_blocks, state = next_epoch_with_attestations(state, False, True)
|
|
blocks += new_blocks
|
|
|
|
if epoch == 0:
|
|
check_finality(state, prev_state, True, False, False)
|
|
elif epoch == 1:
|
|
check_finality(state, prev_state, True, True, False)
|
|
elif epoch == 2:
|
|
# finalized by rule 1
|
|
check_finality(state, prev_state, True, True, True)
|
|
assert state.finalized_epoch == prev_state.previous_justified_epoch
|
|
assert state.finalized_root == prev_state.previous_justified_root
|
|
|
|
yield 'blocks', blocks, [spec.BeaconBlock]
|
|
yield 'post', state
|
|
|
|
|
|
@spec_state_test
|
|
def test_finality_rule_2(state):
|
|
# get past first two epochs that finality does not run on
|
|
next_epoch(state)
|
|
next_epoch(state)
|
|
|
|
yield 'pre', state
|
|
|
|
blocks = []
|
|
for epoch in range(3):
|
|
if epoch == 0:
|
|
prev_state, new_blocks, state = next_epoch_with_attestations(state, True, False)
|
|
check_finality(state, prev_state, True, False, False)
|
|
elif epoch == 1:
|
|
prev_state, new_blocks, state = next_epoch_with_attestations(state, False, False)
|
|
check_finality(state, prev_state, False, True, False)
|
|
elif epoch == 2:
|
|
prev_state, new_blocks, state = next_epoch_with_attestations(state, False, True)
|
|
# finalized by rule 2
|
|
check_finality(state, prev_state, True, False, True)
|
|
assert state.finalized_epoch == prev_state.previous_justified_epoch
|
|
assert state.finalized_root == prev_state.previous_justified_root
|
|
|
|
blocks += new_blocks
|
|
|
|
yield 'blocks', blocks, [spec.BeaconBlock]
|
|
yield 'post', state
|
|
|
|
|
|
@spec_state_test
|
|
def test_finality_rule_3(state):
|
|
"""
|
|
Test scenario described here
|
|
https://github.com/ethereum/eth2.0-specs/issues/611#issuecomment-463612892
|
|
"""
|
|
# get past first two epochs that finality does not run on
|
|
next_epoch(state)
|
|
next_epoch(state)
|
|
|
|
yield 'pre', state
|
|
|
|
blocks = []
|
|
prev_state, new_blocks, state = next_epoch_with_attestations(state, True, False)
|
|
blocks += new_blocks
|
|
check_finality(state, prev_state, True, False, False)
|
|
|
|
# In epoch N, JE is set to N, prev JE is set to N-1
|
|
prev_state, new_blocks, state = next_epoch_with_attestations(state, True, False)
|
|
blocks += new_blocks
|
|
check_finality(state, prev_state, True, True, True)
|
|
|
|
# In epoch N+1, JE is N, prev JE is N-1, and not enough messages get in to do anything
|
|
prev_state, new_blocks, state = next_epoch_with_attestations(state, False, False)
|
|
blocks += new_blocks
|
|
check_finality(state, prev_state, False, True, False)
|
|
|
|
# In epoch N+2, JE is N, prev JE is N, and enough messages from the previous epoch get in to justify N+1.
|
|
# N+1 now becomes the JE. Not enough messages from epoch N+2 itself get in to justify N+2
|
|
prev_state, new_blocks, state = next_epoch_with_attestations(state, False, True)
|
|
blocks += new_blocks
|
|
# rule 2
|
|
check_finality(state, prev_state, True, False, True)
|
|
|
|
# In epoch N+3, LJE is N+1, prev LJE is N, and enough messages get in to justify epochs N+2 and N+3.
|
|
prev_state, new_blocks, state = next_epoch_with_attestations(state, True, True)
|
|
blocks += new_blocks
|
|
# rule 3
|
|
check_finality(state, prev_state, True, True, True)
|
|
assert state.finalized_epoch == prev_state.current_justified_epoch
|
|
assert state.finalized_root == prev_state.current_justified_root
|
|
|
|
yield 'blocks', blocks, [spec.BeaconBlock]
|
|
yield 'post', state
|