853 lines
29 KiB
Nim
853 lines
29 KiB
Nim
# beacon_chain
|
|
# Copyright (c) 2018-2022 Status Research & Development GmbH
|
|
# Licensed and distributed under either of
|
|
# * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT).
|
|
# * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
|
|
# at your option. This file may not be copied, modified, or distributed except according to those terms.
|
|
|
|
when (NimMajor, NimMinor) < (1, 4):
|
|
{.push raises: [Defect].}
|
|
else:
|
|
{.push raises: [].}
|
|
|
|
import
|
|
# Standard library
|
|
std/[sequtils, tables],
|
|
# Status libraries
|
|
stew/[objects, results], chronicles,
|
|
# Internal
|
|
../spec/[beaconstate, helpers, state_transition_block],
|
|
../spec/datatypes/[phase0, altair, bellatrix],
|
|
# Fork choice
|
|
./fork_choice_types, ./proto_array,
|
|
../consensus_object_pools/[spec_cache, blockchain_dag]
|
|
|
|
export results, fork_choice_types
|
|
export proto_array.len
|
|
|
|
# https://github.com/ethereum/consensus-specs/blob/v0.12.1/specs/phase0/fork-choice.md
|
|
# This is a port of https://github.com/sigp/lighthouse/pull/804
|
|
# which is a port of "Proto-Array": https://github.com/protolambda/lmd-ghost
|
|
# See also:
|
|
# - Protolambda port of Lighthouse: https://github.com/protolambda/eth2-py-hacks/blob/ae286567/proto_array.py
|
|
# - Prysmatic writeup: https://hackmd.io/bABJiht3Q9SyV3Ga4FT9lQ#High-level-concept
|
|
# - Gasper Whitepaper: https://arxiv.org/abs/2003.03052
|
|
|
|
# Forward declarations
|
|
# ----------------------------------------------------------------------
|
|
|
|
type Index = fork_choice_types.Index
|
|
|
|
func compute_deltas(
|
|
deltas: var openArray[Delta],
|
|
indices: Table[Eth2Digest, Index],
|
|
indices_offset: Index,
|
|
votes: var openArray[VoteTracker],
|
|
old_balances: openArray[Gwei],
|
|
new_balances: openArray[Gwei]
|
|
): FcResult[void]
|
|
# Fork choice routines
|
|
# ----------------------------------------------------------------------
|
|
|
|
logScope: topics = "fork_choice"
|
|
|
|
func init*(
|
|
T: type ForkChoiceBackend, checkpoints: FinalityCheckpoints,
|
|
hasLowParticipation = false): T =
|
|
T(proto_array: ProtoArray.init(checkpoints, hasLowParticipation))
|
|
|
|
proc init*(
|
|
T: type ForkChoice, epochRef: EpochRef, blck: BlockRef,
|
|
hasLowParticipation = false): T =
|
|
## Initialize a fork choice context for a finalized state - in the finalized
|
|
## state, the justified and finalized checkpoints are the same, so only one
|
|
## is used here
|
|
debug "Initializing fork choice",
|
|
epoch = epochRef.epoch, blck = shortLog(blck)
|
|
|
|
let checkpoint = Checkpoint(root: blck.root, epoch: epochRef.epoch)
|
|
ForkChoice(
|
|
backend: ForkChoiceBackend.init(
|
|
FinalityCheckpoints(
|
|
justified: checkpoint,
|
|
finalized: checkpoint),
|
|
hasLowParticipation),
|
|
checkpoints: Checkpoints(
|
|
justified: BalanceCheckpoint(
|
|
checkpoint: checkpoint,
|
|
balances: epochRef.effective_balances),
|
|
finalized: checkpoint,
|
|
best_justified: checkpoint))
|
|
|
|
func extend[T](s: var seq[T], minLen: int) =
|
|
## Extend a sequence so that it can contains at least `minLen` elements.
|
|
## If it's already bigger, the sequence is unmodified.
|
|
## The extension is zero-initialized
|
|
if s.len < minLen:
|
|
s.setLen(minLen)
|
|
|
|
# https://github.com/ethereum/consensus-specs/blob/v1.2.0-rc.3/specs/phase0/fork-choice.md#should_update_justified_checkpoint
|
|
func should_update_justified_checkpoint(
|
|
self: var Checkpoints, dag: ChainDAGRef,
|
|
new_justified_checkpoint: Checkpoint): FcResult[bool] =
|
|
## To address the bouncing attack, only update conflicting justified
|
|
## checkpoints in the fork choice if in the early slots of the epoch.
|
|
## Otherwise, delay incorporation of new justified checkpoint until next epoch
|
|
## boundary.
|
|
##
|
|
## See https://ethresear.ch/t/prevention-of-bouncing-attack-on-ffg/6114 for
|
|
## more detailed analysis and discussion.
|
|
if self.time.slotOrZero.since_epoch_start() < SAFE_SLOTS_TO_UPDATE_JUSTIFIED:
|
|
return ok true
|
|
|
|
let
|
|
justified_slot = self.justified.checkpoint.epoch.start_slot()
|
|
justified_blck = dag.getBlockRef(new_justified_checkpoint.root).valueOr:
|
|
return err ForkChoiceError(
|
|
kind: fcJustifiedNodeUnknown,
|
|
blockRoot: new_justified_checkpoint.root)
|
|
|
|
let justified_ancestor = justified_blck.atSlot(justified_slot)
|
|
if justified_ancestor.blck.root != self.justified.checkpoint.root:
|
|
return ok false
|
|
|
|
ok true
|
|
|
|
proc update_justified(
|
|
self: var Checkpoints, dag: ChainDAGRef, blck: BlockRef, epoch: Epoch) =
|
|
let
|
|
epochRef = dag.getEpochRef(blck, epoch, false).valueOr:
|
|
# Shouldn't happen for justified data unless out of sync with ChainDAG
|
|
warn "Skipping justified checkpoint update, no EpochRef - report bug",
|
|
blck, epoch, best = self.best_justified.epoch
|
|
return
|
|
justified = Checkpoint(root: blck.root, epoch: epochRef.epoch)
|
|
|
|
trace "Updating justified",
|
|
store = self.justified.checkpoint, state = justified
|
|
self.justified = BalanceCheckpoint(
|
|
checkpoint: Checkpoint(root: blck.root, epoch: epochRef.epoch),
|
|
balances: epochRef.effective_balances)
|
|
|
|
proc update_justified(
|
|
self: var Checkpoints, dag: ChainDAGRef,
|
|
justified: Checkpoint): FcResult[void] =
|
|
let blck = dag.getBlockRef(justified.root).valueOr:
|
|
return err ForkChoiceError(
|
|
kind: fcJustifiedNodeUnknown,
|
|
blockRoot: justified.root)
|
|
|
|
self.update_justified(dag, blck, justified.epoch)
|
|
ok()
|
|
|
|
# https://github.com/ethereum/consensus-specs/blob/v1.2.0-rc.3/specs/phase0/fork-choice.md#on_block
|
|
proc update_checkpoints(
|
|
self: var Checkpoints, dag: ChainDAGRef,
|
|
checkpoints: FinalityCheckpoints): FcResult[void] =
|
|
## Update checkpoints in store if necessary
|
|
# Update justified checkpoint
|
|
if checkpoints.justified.epoch > self.justified.checkpoint.epoch:
|
|
if checkpoints.justified.epoch > self.best_justified.epoch:
|
|
self.best_justified = checkpoints.justified
|
|
|
|
if ? should_update_justified_checkpoint(self, dag, checkpoints.justified):
|
|
? self.update_justified(dag, checkpoints.justified)
|
|
|
|
# Update finalized checkpoint
|
|
if checkpoints.finalized.epoch > self.finalized.epoch:
|
|
trace "Updating finalized",
|
|
store = self.finalized, state = checkpoints.finalized
|
|
self.finalized = checkpoints.finalized
|
|
if checkpoints.justified != self.justified.checkpoint:
|
|
? self.update_justified(dag, checkpoints.justified)
|
|
|
|
ok()
|
|
|
|
# https://github.com/ethereum/consensus-specs/blob/v1.2.0-rc.3/specs/phase0/fork-choice.md#on_tick
|
|
proc on_tick(
|
|
self: var ForkChoice, dag: ChainDAGRef, time: BeaconTime): FcResult[void] =
|
|
## Must be called at least once per slot.
|
|
let previous_time = self.checkpoints.time
|
|
|
|
# update store time
|
|
if time < previous_time:
|
|
return err ForkChoiceError(kind: fcInconsistentTick)
|
|
self.checkpoints.time = time
|
|
|
|
let
|
|
current_slot = time.slotOrZero
|
|
previous_slot = previous_time.slotOrZero
|
|
|
|
# Reset store.proposer_boost_root if this is a new slot
|
|
if current_slot > previous_slot:
|
|
self.checkpoints.proposer_boost_root = ZERO_HASH
|
|
|
|
# Not a new epoch, return
|
|
if not (current_slot > previous_slot and current_slot.is_epoch):
|
|
return ok()
|
|
|
|
# Update store.justified_checkpoint if a better checkpoint on the
|
|
# store.finalized_checkpoint chain
|
|
let
|
|
best_justified_epoch = self.checkpoints.best_justified.epoch
|
|
store_justified_epoch = self.checkpoints.justified.checkpoint.epoch
|
|
if best_justified_epoch > store_justified_epoch:
|
|
let
|
|
blck = dag.getBlockRef(self.checkpoints.best_justified.root).valueOr:
|
|
return err ForkChoiceError(
|
|
kind: fcJustifiedNodeUnknown,
|
|
blockRoot: self.checkpoints.best_justified.root)
|
|
finalized_ancestor = blck.atEpochStart(self.checkpoints.finalized.epoch)
|
|
if finalized_ancestor.blck.root == self.checkpoints.finalized.root:
|
|
self.checkpoints.update_justified(dag, blck, best_justified_epoch)
|
|
|
|
# Pull-up chain tips from previous epoch
|
|
for realized in self.backend.proto_array.realizePendingCheckpoints():
|
|
? self.checkpoints.update_checkpoints(dag, realized)
|
|
|
|
ok()
|
|
|
|
func process_attestation_queue(self: var ForkChoice) {.gcsafe.}
|
|
|
|
proc update_time*(self: var ForkChoice, dag: ChainDAGRef, time: BeaconTime):
|
|
FcResult[void] =
|
|
const step_size = seconds(SECONDS_PER_SLOT.int)
|
|
if time > self.checkpoints.time:
|
|
# Call on_tick at least once per slot.
|
|
while time >= self.checkpoints.time + step_size:
|
|
? self.on_tick(dag, self.checkpoints.time + step_size)
|
|
|
|
if time > self.checkpoints.time:
|
|
# Might create two ticks for the last slot.
|
|
? self.on_tick(dag, time)
|
|
|
|
self.process_attestation_queue() # Only run if time changed!
|
|
|
|
ok()
|
|
|
|
func process_attestation*(
|
|
self: var ForkChoiceBackend,
|
|
validator_index: ValidatorIndex,
|
|
block_root: Eth2Digest,
|
|
target_epoch: Epoch
|
|
) =
|
|
if block_root.isZero:
|
|
return
|
|
|
|
## Add an attestation to the fork choice context
|
|
self.votes.extend(validator_index.int + 1)
|
|
|
|
template vote: untyped = self.votes[validator_index]
|
|
if target_epoch > vote.next_epoch or vote.isZeroMemory:
|
|
vote.next_root = block_root
|
|
vote.next_epoch = target_epoch
|
|
|
|
trace "Integrating vote in fork choice",
|
|
validator_index = validator_index,
|
|
new_vote = shortLog(vote)
|
|
|
|
func process_attestation_queue(self: var ForkChoice) =
|
|
self.queuedAttestations.keepItIf:
|
|
if it.slot < self.checkpoints.time.slotOrZero:
|
|
for validator_index in it.attesting_indices:
|
|
self.backend.process_attestation(
|
|
validator_index, it.block_root, it.slot.epoch())
|
|
false
|
|
else:
|
|
true
|
|
|
|
func contains*(self: ForkChoiceBackend, block_root: Eth2Digest): bool =
|
|
## Returns `true` if a block is known to the fork choice
|
|
## and `false` otherwise.
|
|
##
|
|
## In particular, before adding a block, its parent must be known to the fork choice
|
|
self.proto_array.indices.contains(block_root)
|
|
|
|
# https://github.com/ethereum/consensus-specs/blob/v1.1.5/specs/phase0/fork-choice.md#on_attestation
|
|
proc on_attestation*(
|
|
self: var ForkChoice,
|
|
dag: ChainDAGRef,
|
|
attestation_slot: Slot,
|
|
beacon_block_root: Eth2Digest,
|
|
attesting_indices: openArray[ValidatorIndex],
|
|
wallTime: BeaconTime
|
|
): FcResult[void] =
|
|
? self.update_time(dag, wallTime)
|
|
|
|
if beacon_block_root.isZero:
|
|
return ok()
|
|
|
|
if attestation_slot < self.checkpoints.time.slotOrZero:
|
|
for validator_index in attesting_indices:
|
|
# attestation_slot and target epoch must match, per attestation rules
|
|
self.backend.process_attestation(
|
|
validator_index, beacon_block_root, attestation_slot.epoch)
|
|
else:
|
|
# Spec:
|
|
# Attestations can only affect the fork choice of subsequent slots.
|
|
# Delay consideration in the fork choice until their slot is in the past.
|
|
self.queuedAttestations.add(QueuedAttestation(
|
|
slot: attestation_slot,
|
|
attesting_indices: @attesting_indices,
|
|
block_root: beacon_block_root))
|
|
ok()
|
|
|
|
# https://github.com/ethereum/consensus-specs/blob/v1.2.0-rc.3/specs/phase0/fork-choice.md#on_attester_slashing
|
|
func process_equivocation*(
|
|
self: var ForkChoice,
|
|
validator_index: ValidatorIndex
|
|
) =
|
|
self.backend.votes.extend(validator_index.int + 1)
|
|
|
|
# Disallow future votes
|
|
template vote: untyped = self.backend.votes[validator_index]
|
|
if vote.next_epoch != FAR_FUTURE_EPOCH or not vote.next_root.isZero:
|
|
vote.next_epoch = FAR_FUTURE_EPOCH
|
|
vote.next_root.reset()
|
|
|
|
trace "Integrating equivocation in fork choice",
|
|
validator_index
|
|
|
|
# https://github.com/ethereum/consensus-specs/blob/v1.2.0-rc.3/specs/phase0/fork-choice.md#on_block
|
|
func process_block*(self: var ForkChoiceBackend,
|
|
block_root: Eth2Digest,
|
|
parent_root: Eth2Digest,
|
|
checkpoints: FinalityCheckpoints,
|
|
unrealized = none(FinalityCheckpoints)): FcResult[void] =
|
|
self.proto_array.onBlock(block_root, parent_root, checkpoints, unrealized)
|
|
|
|
proc process_block*(self: var ForkChoice,
|
|
dag: ChainDAGRef,
|
|
epochRef: EpochRef,
|
|
blckRef: BlockRef,
|
|
unrealized: FinalityCheckpoints,
|
|
blck: ForkyTrustedBeaconBlock,
|
|
wallTime: BeaconTime): FcResult[void] =
|
|
? update_time(self, dag, wallTime)
|
|
|
|
for attester_slashing in blck.body.attester_slashings:
|
|
for idx in getValidatorIndices(attester_slashing):
|
|
let i = ValidatorIndex.init(idx).valueOr:
|
|
continue
|
|
self.process_equivocation(i)
|
|
|
|
for attestation in blck.body.attestations:
|
|
if attestation.data.beacon_block_root in self.backend:
|
|
for validator_index in dag.get_attesting_indices(attestation):
|
|
self.backend.process_attestation(
|
|
validator_index,
|
|
attestation.data.beacon_block_root,
|
|
attestation.data.target.epoch)
|
|
|
|
trace "Integrating block in fork choice",
|
|
block_root = shortLog(blckRef)
|
|
|
|
# Add proposer score boost if the block is timely
|
|
let slot = self.checkpoints.time.slotOrZero
|
|
if slot == blck.slot and self.checkpoints.time < slot.attestation_deadline:
|
|
self.checkpoints.proposer_boost_root = blckRef.root
|
|
|
|
# Update checkpoints in store if necessary
|
|
? update_checkpoints(self.checkpoints, dag, epochRef.checkpoints)
|
|
|
|
# If block is from a prior epoch, pull up the post-state to next epoch to
|
|
# realize new finality info
|
|
let unrealized_is_better =
|
|
unrealized.justified.epoch > epochRef.checkpoints.justified.epoch or
|
|
unrealized.finalized.epoch > epochRef.checkpoints.finalized.epoch
|
|
if unrealized_is_better:
|
|
if epochRef.epoch < slot.epoch:
|
|
trace "Pulling up chain tip",
|
|
blck = shortLog(blckRef), checkpoints = epochRef.checkpoints, unrealized
|
|
? update_checkpoints(self.checkpoints, dag, unrealized)
|
|
? process_block(
|
|
self.backend, blckRef.root, blck.parent_root, unrealized)
|
|
else:
|
|
? process_block(
|
|
self.backend, blckRef.root, blck.parent_root,
|
|
epochRef.checkpoints, some unrealized) # Realized in `on_tick`
|
|
else:
|
|
? process_block(
|
|
self.backend, blckRef.root, blck.parent_root, epochRef.checkpoints)
|
|
|
|
ok()
|
|
|
|
func find_head*(
|
|
self: var ForkChoiceBackend,
|
|
current_epoch: Epoch,
|
|
checkpoints: FinalityCheckpoints,
|
|
justified_state_balances: seq[Gwei],
|
|
proposer_boost_root: Eth2Digest
|
|
): FcResult[Eth2Digest] =
|
|
## Returns the new blockchain head
|
|
|
|
# Compute deltas with previous call
|
|
# we might want to reuse the `deltas` buffer across calls
|
|
var deltas = newSeq[Delta](self.proto_array.indices.len)
|
|
? deltas.compute_deltas(
|
|
indices = self.proto_array.indices,
|
|
indices_offset = self.proto_array.nodes.offset,
|
|
votes = self.votes,
|
|
old_balances = self.balances,
|
|
new_balances = justified_state_balances)
|
|
|
|
# Apply score changes
|
|
? self.proto_array.applyScoreChanges(
|
|
deltas, current_epoch, checkpoints,
|
|
justified_state_balances, proposer_boost_root)
|
|
|
|
self.balances = justified_state_balances
|
|
|
|
# Find the best block
|
|
var new_head{.noinit.}: Eth2Digest
|
|
? self.proto_array.findHead(new_head, checkpoints.justified.root)
|
|
|
|
trace "Fork choice requested",
|
|
checkpoints, fork_choice_head = shortLog(new_head)
|
|
|
|
return ok(new_head)
|
|
|
|
# https://github.com/ethereum/consensus-specs/blob/v0.12.1/specs/phase0/fork-choice.md#get_head
|
|
proc get_head*(self: var ForkChoice,
|
|
dag: ChainDAGRef,
|
|
wallTime: BeaconTime): FcResult[Eth2Digest] =
|
|
? self.update_time(dag, wallTime)
|
|
|
|
self.backend.find_head(
|
|
self.checkpoints.time.slotOrZero.epoch,
|
|
FinalityCheckpoints(
|
|
justified: self.checkpoints.justified.checkpoint,
|
|
finalized: self.checkpoints.finalized),
|
|
self.checkpoints.justified.balances,
|
|
self.checkpoints.proposer_boost_root)
|
|
|
|
# https://github.com/ethereum/consensus-specs/blob/v1.2.0-rc.3/fork_choice/safe-block.md#get_safe_beacon_block_root
|
|
func get_safe_beacon_block_root*(self: ForkChoice): Eth2Digest =
|
|
# Use most recent justified block as a stopgap
|
|
self.checkpoints.justified.checkpoint.root
|
|
|
|
func prune*(
|
|
self: var ForkChoiceBackend, finalized_root: Eth2Digest
|
|
): FcResult[void] =
|
|
## Prune blocks preceding the finalized root as they are now unneeded.
|
|
self.proto_array.prune(finalized_root)
|
|
|
|
func prune*(self: var ForkChoice): FcResult[void] =
|
|
self.backend.prune(self.checkpoints.finalized.root)
|
|
|
|
func mark_root_invalid*(self: var ForkChoice, root: Eth2Digest) =
|
|
try:
|
|
let nodePhysicalIdx =
|
|
self.backend.proto_array.indices[root] -
|
|
self.backend.proto_array.nodes.offset
|
|
if nodePhysicalIdx < self.backend.proto_array.nodes.buf.len:
|
|
self.backend.proto_array.nodes.buf[nodePhysicalIdx].invalid = true
|
|
# Best-effort; attempts to mark unknown roots invalid harmlessly ignored
|
|
except KeyError:
|
|
discard
|
|
|
|
func compute_deltas(
|
|
deltas: var openArray[Delta],
|
|
indices: Table[Eth2Digest, Index],
|
|
indices_offset: Index,
|
|
votes: var openArray[VoteTracker],
|
|
old_balances: openArray[Gwei],
|
|
new_balances: openArray[Gwei]
|
|
): FcResult[void] =
|
|
## Update `deltas`
|
|
## between old and new balances
|
|
## between votes
|
|
##
|
|
## `deltas.len` must match `indices.len` (length match)
|
|
##
|
|
## Error:
|
|
## - If a value in indices is greater than `indices.len`
|
|
## - If a `Eth2Digest` in `votes` does not exist in `indices`
|
|
## except for the `default(Eth2Digest)` (i.e. zero hash)
|
|
|
|
for val_index, vote in votes.mpairs():
|
|
# No need to create a score change if the validator has never voted
|
|
# or if votes are for the zero hash (alias to the genesis block)
|
|
if vote.current_root.isZero and vote.next_root.isZero:
|
|
continue
|
|
|
|
# If the validator was not included in `old_balances` (i.e. did not exist)
|
|
# its balance is zero
|
|
let old_balance = if val_index < old_balances.len: old_balances[val_index]
|
|
else: 0
|
|
|
|
# If the validator is not known in the `new_balances` then use balance of zero
|
|
#
|
|
# It is possible that there is a vote for an unknown validator if we change our
|
|
# justified state to a new state with a higher epoch on a different fork
|
|
# because that fork may have on-boarded less validators than the previous fork.
|
|
#
|
|
# Note that attesters are not different as they are activated only under finality
|
|
let new_balance = if val_index < new_balances.len: new_balances[val_index]
|
|
else: 0
|
|
|
|
if vote.current_root != vote.next_root or old_balance != new_balance:
|
|
# Ignore the current or next vote if it is not known in `indices`.
|
|
# We assume that it is outside of our tree (i.e., pre-finalization) and therefore not interesting.
|
|
if vote.current_root in indices:
|
|
let index = indices.unsafeGet(vote.current_root) - indices_offset
|
|
if index >= deltas.len:
|
|
return err ForkChoiceError(
|
|
kind: fcInvalidNodeDelta,
|
|
index: index)
|
|
deltas[index] -= Delta old_balance
|
|
# Note that delta can be negative
|
|
# TODO: is int64 big enough?
|
|
|
|
if vote.next_epoch != FAR_FUTURE_EPOCH or not vote.next_root.isZero:
|
|
if vote.next_root in indices:
|
|
let index = indices.unsafeGet(vote.next_root) - indices_offset
|
|
if index >= deltas.len:
|
|
return err ForkChoiceError(
|
|
kind: fcInvalidNodeDelta,
|
|
index: index)
|
|
deltas[index] += Delta new_balance
|
|
# Note that delta can be negative
|
|
# TODO: is int64 big enough?
|
|
|
|
vote.current_root = vote.next_root
|
|
return ok()
|
|
|
|
# Sanity checks
|
|
# ----------------------------------------------------------------------
|
|
# Sanity checks on internal private procedures
|
|
|
|
when isMainModule:
|
|
import stew/endians2
|
|
|
|
func fakeHash(index: SomeInteger): Eth2Digest =
|
|
## Create fake hashes
|
|
## Those are just the value serialized in big-endian
|
|
## We add 16x16 to avoid having a zero hash are those are special cased
|
|
## We store them in the first 8 bytes
|
|
## as those are the one used in hash tables Table[Eth2Digest, T]
|
|
result.data[0 ..< 8] = (16*16+index).uint64.toBytesBE()
|
|
|
|
proc tZeroHash() =
|
|
echo " fork_choice compute_deltas - test zero votes"
|
|
|
|
const validator_count = 16
|
|
var deltas = newSeqUninitialized[Delta](validator_count)
|
|
|
|
var indices: Table[Eth2Digest, Index]
|
|
var votes: seq[VoteTracker]
|
|
var old_balances: seq[Gwei]
|
|
var new_balances: seq[Gwei]
|
|
|
|
for i in 0 ..< validator_count:
|
|
indices.add fakeHash(i), i
|
|
votes.add default(VoteTracker)
|
|
old_balances.add 0
|
|
new_balances.add 0
|
|
|
|
let err = deltas.compute_deltas(
|
|
indices, indices_offset = 0, votes, old_balances, new_balances
|
|
)
|
|
|
|
doAssert err.isOk, "compute_deltas finished with error: " & $err
|
|
|
|
doAssert deltas == newSeq[Delta](validator_count), "deltas should be zeros"
|
|
|
|
for vote in votes:
|
|
doAssert vote.current_root == vote.next_root, "The vote should have been updated"
|
|
|
|
|
|
proc tAll_voted_the_same() =
|
|
echo " fork_choice compute_deltas - test all same votes"
|
|
|
|
const
|
|
Balance = Gwei(42)
|
|
validator_count = 16
|
|
var deltas = newSeqUninitialized[Delta](validator_count)
|
|
|
|
var indices: Table[Eth2Digest, Index]
|
|
var votes: seq[VoteTracker]
|
|
var old_balances: seq[Gwei]
|
|
var new_balances: seq[Gwei]
|
|
|
|
for i in 0 ..< validator_count:
|
|
indices.add fakeHash(i), i
|
|
votes.add VoteTracker(
|
|
current_root: default(Eth2Digest),
|
|
next_root: fakeHash(0), # Get a non-zero hash
|
|
next_epoch: Epoch(0)
|
|
)
|
|
old_balances.add Balance
|
|
new_balances.add Balance
|
|
|
|
let err = deltas.compute_deltas(
|
|
indices, indices_offset = 0, votes, old_balances, new_balances
|
|
)
|
|
|
|
doAssert err.isOk, "compute_deltas finished with error: " & $err
|
|
|
|
for i, delta in deltas:
|
|
if i == 0:
|
|
doAssert delta == Delta(Balance * validator_count), "The 0th root should have a delta"
|
|
else:
|
|
doAssert delta == 0, "The non-0 indexes should have a zero delta"
|
|
|
|
for vote in votes:
|
|
doAssert vote.current_root == vote.next_root, "The vote should have been updated"
|
|
|
|
|
|
proc tDifferent_votes() =
|
|
echo " fork_choice compute_deltas - test all different votes"
|
|
|
|
const
|
|
Balance = Gwei(42)
|
|
validator_count = 16
|
|
var deltas = newSeqUninitialized[Delta](validator_count)
|
|
|
|
var indices: Table[Eth2Digest, Index]
|
|
var votes: seq[VoteTracker]
|
|
var old_balances: seq[Gwei]
|
|
var new_balances: seq[Gwei]
|
|
|
|
for i in 0 ..< validator_count:
|
|
indices.add fakeHash(i), i
|
|
votes.add VoteTracker(
|
|
current_root: default(Eth2Digest),
|
|
next_root: fakeHash(i), # Each vote for a different root
|
|
next_epoch: Epoch(0)
|
|
)
|
|
old_balances.add Balance
|
|
new_balances.add Balance
|
|
|
|
let err = deltas.compute_deltas(
|
|
indices, indices_offset = 0, votes, old_balances, new_balances
|
|
)
|
|
|
|
doAssert err.isOk, "compute_deltas finished with error: " & $err
|
|
|
|
for i, delta in deltas:
|
|
doAssert delta == Delta(Balance), "Each root should have a delta"
|
|
|
|
for vote in votes:
|
|
doAssert vote.current_root == vote.next_root, "The vote should have been updated"
|
|
|
|
|
|
proc tMoving_votes() =
|
|
echo " fork_choice compute_deltas - test moving votes"
|
|
|
|
const
|
|
Balance = Gwei(42)
|
|
validator_count = 16
|
|
TotalDeltas = Delta(Balance * validator_count)
|
|
var deltas = newSeqUninitialized[Delta](validator_count)
|
|
|
|
var indices: Table[Eth2Digest, Index]
|
|
var votes: seq[VoteTracker]
|
|
var old_balances: seq[Gwei]
|
|
var new_balances: seq[Gwei]
|
|
|
|
for i in 0 ..< validator_count:
|
|
indices.add fakeHash(i), i
|
|
votes.add VoteTracker(
|
|
# Move vote from root 0 to root 1
|
|
current_root: fakeHash(0),
|
|
next_root: fakeHash(1),
|
|
next_epoch: Epoch(0)
|
|
)
|
|
old_balances.add Balance
|
|
new_balances.add Balance
|
|
|
|
let err = deltas.compute_deltas(
|
|
indices, indices_offset = 0, votes, old_balances, new_balances
|
|
)
|
|
|
|
doAssert err.isOk, "compute_deltas finished with error: " & $err
|
|
|
|
for i, delta in deltas:
|
|
if i == 0:
|
|
doAssert delta == -TotalDeltas, "0th root should have a negative delta"
|
|
elif i == 1:
|
|
doAssert delta == TotalDeltas, "1st root should have a positive delta"
|
|
else:
|
|
doAssert delta == 0, "The non-0 and non-1 indexes should have a zero delta"
|
|
|
|
for vote in votes:
|
|
doAssert vote.current_root == vote.next_root, "The vote should have been updated"
|
|
|
|
|
|
proc tMove_out_of_tree() =
|
|
echo " fork_choice compute_deltas - test votes for unknown subtree"
|
|
|
|
const Balance = Gwei(42)
|
|
|
|
var indices: Table[Eth2Digest, Index]
|
|
var votes: seq[VoteTracker]
|
|
|
|
# Add a block
|
|
indices.add fakeHash(1), 0
|
|
|
|
# 2 validators
|
|
var deltas = newSeqUninitialized[Delta](2)
|
|
let old_balances = @[Balance, Balance]
|
|
let new_balances = @[Balance, Balance]
|
|
|
|
# One validator moves their vote from the block to the zero hash
|
|
votes.add VoteTracker(
|
|
current_root: fakeHash(1),
|
|
next_root: default(Eth2Digest),
|
|
next_epoch: Epoch(0)
|
|
)
|
|
|
|
# One validator moves their vote from the block to something outside of the tree
|
|
votes.add VoteTracker(
|
|
current_root: fakeHash(1),
|
|
next_root: fakeHash(1337),
|
|
next_epoch: Epoch(0)
|
|
)
|
|
|
|
let err = deltas.compute_deltas(
|
|
indices, indices_offset = 0, votes, old_balances, new_balances
|
|
)
|
|
|
|
doAssert err.isOk, "compute_deltas finished with error: " & $err
|
|
|
|
doAssert deltas[0] == -Delta(Balance)*2, "The 0th block should have lost both balances."
|
|
|
|
for vote in votes:
|
|
doAssert vote.current_root == vote.next_root, "The vote should have been updated"
|
|
|
|
|
|
proc tChanging_balances() =
|
|
echo " fork_choice compute_deltas - test changing balances"
|
|
|
|
const
|
|
OldBalance = Gwei(42)
|
|
NewBalance = OldBalance * 2
|
|
validator_count = 16
|
|
TotalOldDeltas = Delta(OldBalance * validator_count)
|
|
TotalNewDeltas = Delta(NewBalance * validator_count)
|
|
var deltas = newSeqUninitialized[Delta](validator_count)
|
|
|
|
var indices: Table[Eth2Digest, Index]
|
|
var votes: seq[VoteTracker]
|
|
var old_balances: seq[Gwei]
|
|
var new_balances: seq[Gwei]
|
|
|
|
for i in 0 ..< validator_count:
|
|
indices.add fakeHash(i), i
|
|
votes.add VoteTracker(
|
|
# Move vote from root 0 to root 1
|
|
current_root: fakeHash(0),
|
|
next_root: fakeHash(1),
|
|
next_epoch: Epoch(0)
|
|
)
|
|
old_balances.add OldBalance
|
|
new_balances.add NewBalance
|
|
|
|
let err = deltas.compute_deltas(
|
|
indices, indices_offset = 0, votes, old_balances, new_balances
|
|
)
|
|
|
|
doAssert err.isOk, "compute_deltas finished with error: " & $err
|
|
|
|
for i, delta in deltas:
|
|
if i == 0:
|
|
doAssert delta == -TotalOldDeltas, "0th root should have a negative delta"
|
|
elif i == 1:
|
|
doAssert delta == TotalNewDeltas, "1st root should have a positive delta"
|
|
else:
|
|
doAssert delta == 0, "The non-0 and non-1 indexes should have a zero delta"
|
|
|
|
for vote in votes:
|
|
doAssert vote.current_root == vote.next_root, "The vote should have been updated"
|
|
|
|
|
|
proc tValidator_appears() =
|
|
echo " fork_choice compute_deltas - test validator appears"
|
|
|
|
const Balance = Gwei(42)
|
|
|
|
var indices: Table[Eth2Digest, Index]
|
|
var votes: seq[VoteTracker]
|
|
|
|
# Add 2 blocks
|
|
indices.add fakeHash(1), 0
|
|
indices.add fakeHash(2), 1
|
|
|
|
# 1 validator at the start, 2 at the end
|
|
var deltas = newSeqUninitialized[Delta](2)
|
|
let old_balances = @[Balance]
|
|
let new_balances = @[Balance, Balance]
|
|
|
|
# Both moves vote from Block 1 to 2
|
|
for _ in 0 ..< 2:
|
|
votes.add VoteTracker(
|
|
current_root: fakeHash(1),
|
|
next_root: fakeHash(2),
|
|
next_epoch: Epoch(0)
|
|
)
|
|
|
|
|
|
let err = deltas.compute_deltas(
|
|
indices, indices_offset = 0, votes, old_balances, new_balances
|
|
)
|
|
|
|
doAssert err.isOk, "compute_deltas finished with error: " & $err
|
|
|
|
doAssert deltas[0] == -Delta(Balance), "Block 1 should have lost only 1 balance"
|
|
doAssert deltas[1] == Delta(Balance)*2, "Block 2 should have gained 2 balances"
|
|
|
|
for vote in votes:
|
|
doAssert vote.current_root == vote.next_root, "The vote should have been updated"
|
|
|
|
|
|
proc tValidator_disappears() =
|
|
echo " fork_choice compute_deltas - test validator disappears"
|
|
|
|
const Balance = Gwei(42)
|
|
|
|
var indices: Table[Eth2Digest, Index]
|
|
var votes: seq[VoteTracker]
|
|
|
|
# Add 2 blocks
|
|
indices.add fakeHash(1), 0
|
|
indices.add fakeHash(2), 1
|
|
|
|
# 1 validator at the start, 2 at the end
|
|
var deltas = newSeqUninitialized[Delta](2)
|
|
let old_balances = @[Balance, Balance]
|
|
let new_balances = @[Balance]
|
|
|
|
# Both moves vote from Block 1 to 2
|
|
for _ in 0 ..< 2:
|
|
votes.add VoteTracker(
|
|
current_root: fakeHash(1),
|
|
next_root: fakeHash(2),
|
|
next_epoch: Epoch(0)
|
|
)
|
|
|
|
|
|
let err = deltas.compute_deltas(
|
|
indices, indices_offset = 0, votes, old_balances, new_balances
|
|
)
|
|
|
|
doAssert err.isOk, "compute_deltas finished with error: " & $err
|
|
|
|
doAssert deltas[0] == -Delta(Balance)*2, "Block 1 should have lost 2 balances"
|
|
doAssert deltas[1] == Delta(Balance), "Block 2 should have gained 1 balance"
|
|
|
|
for vote in votes:
|
|
doAssert vote.current_root == vote.next_root, "The vote should have been updated"
|
|
|
|
|
|
# ----------------------------------------------------------------------
|
|
|
|
echo "fork_choice internal tests for compute_deltas"
|
|
tZeroHash()
|
|
tAll_voted_the_same()
|
|
tDifferent_votes()
|
|
tMoving_votes()
|
|
tChanging_balances()
|
|
tValidator_appears()
|
|
tValidator_disappears()
|