nimbus-eth2/tests/fork_choice/interpreter.nim

111 lines
4.4 KiB
Nim

# beacon_chain
# Copyright (c) 2018 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.
import
# Standard library
std/strformat, std/tables, std/options,
# Status libraries
stew/[results, endians2],
# Internals
../../beacon_chain/spec/[datatypes, digest],
../../beacon_chain/fork_choice/[fork_choice, fork_choice_types]
export results, datatypes, digest, fork_choice, fork_choice_types, tables, options
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()
# The fork choice tests are quite complex.
# For flexibility in block arrival, timers, operations sequencing, ...
# we create a small interpreter that will trigger events in proper order
# before fork choice.
type
OpKind* = enum
FindHead
InvalidFindHead
ProcessBlock
ProcessAttestation
Prune
Operation* = object
# variant specific fields
case kind*: OpKind
of FindHead, InvalidFindHead:
justified_epoch*: Epoch
justified_root*: Eth2Digest
finalized_epoch*: Epoch
justified_state_balances*: seq[Gwei]
expected_head*: Eth2Digest
of ProcessBlock:
root*: Eth2Digest
parent_root*: Eth2Digest
blk_justified_epoch*: Epoch
blk_finalized_epoch*: Epoch
of ProcessAttestation:
validator_index*: ValidatorIndex
block_root*: Eth2Digest
target_epoch*: Epoch
of Prune: # ProtoArray specific
finalized_root*: Eth2Digest
prune_threshold*: int
expected_len*: int
func apply(ctx: var ForkChoiceBackend, id: int, op: Operation) =
## Apply the specified operation to a ForkChoice context
## ``id`` is additional debugging info. It is the
## operation index.
# debugEcho " ========================================================================================="
case op.kind
of FindHead, InvalidFindHead:
let r = ctx.find_head(
op.justified_epoch,
op.justified_root,
op.finalized_epoch,
op.justified_state_balances
)
if op.kind == FindHead:
doAssert r.isOk(), &"find_head (op #{id}) returned an error: {r.error}"
doAssert r.get() == op.expected_head, &"find_head (op #{id}) returned an incorrect result: {r.get()} (expected: {op.expected_head})"
debugEcho " Found expected head: 0x", op.expected_head, " from justified checkpoint(epoch: ", op.justified_epoch, ", root: 0x", op.justified_root, ")"
else:
doAssert r.isErr(), "find_head was unexpectedly successful"
debugEcho " Detected an expected invalid head"
of ProcessBlock:
let r = ctx.process_block(
block_root = op.root,
parent_root = op.parent_root,
justified_epoch = op.blk_justified_epoch,
finalized_epoch = op.blk_finalized_epoch
)
doAssert r.isOk(), &"process_block (op #{id}) returned an error: {r.error}"
debugEcho " Processed block 0x", op.root, " with parent 0x", op.parent_root, " and justified epoch ", op.blk_justified_epoch
of ProcessAttestation:
ctx.process_attestation(
validator_index = op.validator_index,
block_root = op.block_root,
target_epoch = op.target_epoch
)
debugEcho " Processed att target 0x", op.block_root, " from validator ", op.validator_index, " for epoch ", op.target_epoch
of Prune:
ctx.proto_array.prune_threshold = op.prune_threshold
let r = ctx.maybe_prune(op.finalized_root)
doAssert r.isOk(), &"prune (op #{id}) returned an error: {r.error}"
doAssert ctx.proto_array.nodes.len == op.expected_len,
&"prune (op #{id}): the resulting length ({ctx.proto_array.nodes.len}) was not expected ({op.expected_len})"
debugEcho " Maybe_pruned block preceding finalized block 0x", op.finalized_root
func run*(ctx: var ForkChoiceBackend, ops: seq[Operation]) =
## Apply a sequence of fork-choice operations on a store
for i, op in ops:
ctx.apply(i, op)