Official state tests - parsing and loading beacon state (#227)

* initial commit of official state tests

* sanity check fixture

* Parsing official state test is mostly working
(Except BLS signature)

* Successfully load state test

* Use json-serialization instead of json and display deserialized and from scratch beacon state hashes

* Add official state test as a smoke parsing test

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "tests/official/eth2.0-tests"]
+	path = tests/official/eth2.0-tests
+	url = https://github.com/ethereum/eth2.0-tests

tests/all_tests.nim

@@ -16,4 +16,5 @@ import
   ./test_ssz,
   ./test_state_transition,
   ./test_sync_protocol,
-  ./test_validator
+  ./test_validator,
+  ./official/test_fixture_state

tests/official/README.md

@@ -0,0 +1,18 @@
+Note on serialization hacks:
+
+### FAR_FUTURE_SLOT (18446744073709551615)
+
+The FAR_FUTURE_SLOT (18446744073709551615) has been rewritten as a string **in the YAML file**
+as it's 2^64-1 and Nim by default try to parse it into a int64 (which can represents up to 2^63-1).
+
+The YAML file is then converted to JSON for easy input to the json serialization/deserialization
+with beacon chain type support.
+
+"18446744073709551615" is then replaced again by uint64 18446744073709551615.
+
+### Compressed signature
+
+In `latest_block_header` field, the signatures and randao_reveals are
+`"0x000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"`
+but that is not a valid compressed BLS signature, the zero signature should be:
+`"0xc00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"`

tests/official/eth2.0-tests

@@ -0,0 +1 @@
+Subproject commit 3ec28295b0c8365f0ec7ad79cfe933755021ee1b

tests/official/fixtures_utils.nim

@@ -0,0 +1,153 @@
+# 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 http://opensource.org/licenses/MIT).
+#   * Apache v2 license (license terms in the root directory or at http://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 lib
+  json, streams, strutils,
+  # Dependencies
+  yaml.tojson,
+  # Status libs
+  blscurve, nimcrypto, byteutils,
+  eth/common, serialization, json_serialization,
+  # Beacon chain internals
+  ../../beacon_chain/spec/[datatypes, crypto, digest]
+
+export nimcrypto.toHex
+
+type
+  # TODO: use ref object to avoid allocating
+  #       so much on the stack - pending https://github.com/status-im/nim-json-serialization/issues/3
+  StateTest* = object
+    title*: string
+    summary*: string
+    test_suite*: string
+    fork*: string
+    test_cases*: seq[TestCase]
+  
+  TestConstants* = object
+    SHARD_COUNT*: int
+    TARGET_COMMITTEE_SIZE*: int
+    MAX_BALANCE_CHURN_QUOTIENT*: int
+    MAX_INDICES_PER_SLASHABLE_VOTE*: int
+    MAX_EXIT_DEQUEUES_PER_EPOCH*: int
+    SHUFFLE_ROUND_COUNT*: int
+    DEPOSIT_CONTRACT_TREE_DEPTH*: int
+    MIN_DEPOSIT_AMOUNT*: uint64
+    MAX_DEPOSIT_AMOUNT*: uint64
+    FORK_CHOICE_BALANCE_INCREMENT*: uint64
+    EJECTION_BALANCE*: uint64
+    GENESIS_FORK_VERSION*: uint32
+    GENESIS_SLOT*: Slot
+    GENESIS_EPOCH*: Epoch
+    GENESIS_START_SHARD*: uint64
+    BLS_WITHDRAWAL_PREFIX_BYTE*: array[1, byte]
+    SECONDS_PER_SLOT*: uint64
+    MIN_ATTESTATION_INCLUSION_DELAY*: uint64
+    SLOTS_PER_EPOCH*: int
+    MIN_SEED_LOOKAHEAD*: int
+    ACTIVATION_EXIT_DELAY*: int
+    EPOCHS_PER_ETH1_VOTING_PERIOD*: uint64
+    SLOTS_PER_HISTORICAL_ROOT*: int
+    MIN_VALIDATOR_WITHDRAWABILITY_DELAY*: uint64
+    PERSISTENT_COMMITTEE_PERIOD*: uint64
+    LATEST_RANDAO_MIXES_LENGTH*: int
+    LATEST_ACTIVE_INDEX_ROOTS_LENGTH*: int
+    LATEST_SLASHED_EXIT_LENGTH*: int
+    BASE_REWARD_QUOTIENT*: uint64
+    WHISTLEBLOWER_REWARD_QUOTIENT*: uint64
+    ATTESTATION_INCLUSION_REWARD_QUOTIENT*: uint64
+    INACTIVITY_PENALTY_QUOTIENT*: uint64
+    MIN_PENALTY_QUOTIENT*: int
+    MAX_PROPOSER_SLASHINGS*: int
+    MAX_ATTESTER_SLASHINGS*: int
+    MAX_ATTESTATIONS*: int
+    MAX_DEPOSITS*: int
+    MAX_VOLUNTARY_EXITS*: int
+    MAX_TRANSFERS*: int
+    DOMAIN_BEACON_BLOCK*: SignatureDomain
+    DOMAIN_RANDAO*: SignatureDomain
+    DOMAIN_ATTESTATION*: SignatureDomain
+    DOMAIN_DEPOSIT*: SignatureDomain
+    DOMAIN_VOLUNTARY_EXIT*: SignatureDomain
+    DOMAIN_TRANSFER*: SignatureDomain
+
+  TestCase* = object
+    name*: string
+    config*: TestConstants
+    verify_signatures*: bool
+    initial_state*: BeaconState
+    blocks*: seq[BeaconBlock]
+    expected_state*: ExpectedState
+  
+  ExpectedState* = object
+    ## TODO what is this?
+    slot*: Slot
+
+# #######################
+# Default init
+proc default*(T: typedesc): T = discard
+
+# #######################
+# JSON deserialization
+
+proc readValue*[N: static int](r: var JsonReader, a: var array[N, byte]) {.inline.} =
+  # Needed for;
+  #   - BLS_WITHDRAWAL_PREFIX_BYTE
+  #   - FOrk datatypes
+  # TODO: are all bytes and bytearray serialized as hex?
+  #       if so export that to nim-eth
+  hexToByteArray(r.readValue(string), a)
+
+proc parseStateTests*(jsonPath: string): StateTest =
+  try:
+    result = Json.loadFile(jsonPath, StateTest)
+  except SerializationError as err:
+    writeStackTrace()
+    stderr.write "Json load issue for file \"", jsonPath, "\"\n"
+    stderr.write err.formatMsg(jsonPath), "\n"
+    quit 1
+
+# #######################
+# Yaml to JSON conversion
+
+proc yamlToJson*(file: string): seq[JsonNode] =
+  try:
+    let fs = openFileStream(file)
+    defer: fs.close()
+    result = fs.loadToJson()
+  except IOError:
+    echo "Exception when reading file: " & file
+    raise
+  except OverflowError:
+    echo "Overflow exception when parsing. Did you stringify 18446744073709551615 (-1)?"
+    raise
+
+when isMainModule:
+  # Do not forget to stringify FAR_EPOCH_SLOT = 18446744073709551615 (-1) in the YAML file
+  # And unstringify it in the produced JSON file
+
+  import os, typetraits
+
+  const
+    DefaultYML = "tests/official/sanity-check_default-config_100-vals-first_test.yaml"
+    DefaultOutputPath = "tests/official/sanity-check_default-config_100-vals-first_test.json"
+
+  var fileName, outputPath: string
+  if paramCount() == 0:
+    fileName = DefaultYML
+    outputPath = DefaultOutputPath
+  elif paramCount() == 1:
+    fileName = paramStr(1)
+    outputPath = DefaultOutputPath
+  elif paramCount() >= 2:
+    fileName = paramStr(1)
+    outputPath = paramStr(2)
+
+  let jsonString = $DefaultYML.yamlToJson[0]
+  DefaultOutputPath.writeFile jsonString
+
+

tests/official/test_fixture_state.nim

@@ -0,0 +1,53 @@
+# 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 http://opensource.org/licenses/MIT).
+#   * Apache v2 license (license terms in the root directory or at http://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 lib
+  ospaths, strutils, json, unittest,
+  # Beacon chain internals
+  ../../beacon_chain/spec/[datatypes, crypto, digest, beaconstate],
+  ../../beacon_chain/ssz,
+  # Test utilities
+  ./fixtures_utils
+
+const TestFolder = currentSourcePath.rsplit(DirSep, 1)[0]
+const TestsPath = "/sanity-check_default-config_100-vals-first_test.json"
+
+suite "Official - State tests": # Initializing a beacon state from the deposits
+  var stateTests: StateTest
+  test "Parsing the official state tests into Nimbus beacon types":
+    stateTests = parseStateTests(TestFolder & TestsPath)
+    doAssert $stateTests.test_cases[0].name == "test_empty_block_transition"
+  var initialState: BeaconState
+  test "Initializing from scratch a new beacon chain with the same constants and deposit configuration as official state":
+    var deposits: seq[Deposit]
+    var index = 0'u64
+    for v in stateTests.test_cases[0].initial_state.validator_registry:
+      deposits.add Deposit(
+        proof: default(array[DEPOSIT_CONTRACT_TREE_DEPTH, Eth2Digest]),
+        index: index,
+        deposit_data: DepositData(
+          amount: 32000000000'u64, # TODO: read that from validator_balances
+          timestamp: 0'u64,        # TODO: not initialized in test
+          deposit_input: DepositInput(
+            pubkey: v.pubkey,
+            withdrawal_credentials: v.withdrawal_credentials,
+            proof_of_possession: default(ValidatorSig) # TODO: not initialized in test
+          )
+        )
+      )
+
+    initialState = get_genesis_beacon_state(
+      genesis_validator_deposits = deposits,
+      genesis_time = 0,
+      genesis_eth1_data = Eth1Data()
+    )
+  test "[For information] Comparing state hashes":
+    # TODO - Add official hashes when available
+    # TODO - Make that a blocking test requirement
+    echo "Deserialized state hash: 0x" & $stateTests.test_cases[0].initial_state.hash_tree_root()
+    echo "From-scratch state hash: 0x" & $initialState.hash_tree_root()