make Gwei distinct (#6090)

#6087 introduced a subtle change to `nim-web3` resulting in `Gwei` to be
serialized differently than before. Using a `distinct` type for `Gwei`
improves type safety and avoids such problems in the future.

beacon_chain/beacon_chain_db_immutable.nim

@@ -44,13 +44,13 @@ type
 
     # Registry
     validators*: HashList[ValidatorStatus, Limit VALIDATOR_REGISTRY_LIMIT]
-    balances*: HashList[uint64, Limit VALIDATOR_REGISTRY_LIMIT]
+    balances*: HashList[Gwei, Limit VALIDATOR_REGISTRY_LIMIT]
 
     # Randomness
     randao_mixes*: HashArray[Limit EPOCHS_PER_HISTORICAL_VECTOR, Eth2Digest]
 
     # Slashings
-    slashings*: HashArray[Limit EPOCHS_PER_SLASHINGS_VECTOR, uint64]
+    slashings*: HashArray[Limit EPOCHS_PER_SLASHINGS_VECTOR, Gwei]
       ## Per-epoch sums of slashed effective balances
 
     # Attestations
@@ -97,13 +97,13 @@ type
 
     # Registry
     validators*: HashList[ValidatorStatus, Limit VALIDATOR_REGISTRY_LIMIT]
-    balances*: HashList[uint64, Limit VALIDATOR_REGISTRY_LIMIT]
+    balances*: HashList[Gwei, Limit VALIDATOR_REGISTRY_LIMIT]
 
     # Randomness
     randao_mixes*: HashArray[Limit EPOCHS_PER_HISTORICAL_VECTOR, Eth2Digest]
 
     # Slashings
-    slashings*: HashArray[Limit EPOCHS_PER_SLASHINGS_VECTOR, uint64]
+    slashings*: HashArray[Limit EPOCHS_PER_SLASHINGS_VECTOR, Gwei]
       ## Per-epoch sums of slashed effective balances
 
     # Participation
@@ -155,13 +155,13 @@ type
 
     # Registry
     validators*: HashList[ValidatorStatus, Limit VALIDATOR_REGISTRY_LIMIT]
-    balances*: HashList[uint64, Limit VALIDATOR_REGISTRY_LIMIT]
+    balances*: HashList[Gwei, Limit VALIDATOR_REGISTRY_LIMIT]
 
     # Randomness
     randao_mixes*: HashArray[Limit EPOCHS_PER_HISTORICAL_VECTOR, Eth2Digest]
 
     # Slashings
-    slashings*: HashArray[Limit EPOCHS_PER_SLASHINGS_VECTOR, uint64]
+    slashings*: HashArray[Limit EPOCHS_PER_SLASHINGS_VECTOR, Gwei]
       ## Per-epoch sums of slashed effective balances
 
     # Participation

beacon_chain/beacon_node.nim

@@ -89,7 +89,7 @@ type
     processor*: ref Eth2Processor
     blockProcessor*: ref BlockProcessor
     consensusManager*: ref ConsensusManager
-    attachedValidatorBalanceTotal*: uint64
+    attachedValidatorBalanceTotal*: Gwei
     gossipState*: GossipState
     blocksGossipState*: GossipState
     beaconClock*: BeaconClock

beacon_chain/el/el_manager.nim

@@ -1368,7 +1368,7 @@ func depositEventsToBlocks(depositsList: openArray[JsonString]): seq[Eth1Block]
     lastEth1Block.deposits.add DepositData(
       pubkey: ValidatorPubKey.init(pubkey.toArray),
       withdrawal_credentials: Eth2Digest(data: withdrawalCredentials.toArray),
-      amount: bytes_to_uint64(amount.toArray),
+      amount: bytes_to_uint64(amount.toArray).Gwei,
       signature: ValidatorSig.init(signature.toArray))
 
 type

beacon_chain/fork_choice/fork_choice.nim

@@ -434,7 +434,7 @@ func compute_deltas(
     # 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
+                      else: 0.Gwei
 
     # If the validator is not known in the `new_balances` then use balance of zero
     #
@@ -444,7 +444,7 @@ func compute_deltas(
     #
     # 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
+                      else: 0.Gwei
 
     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`.

beacon_chain/fork_choice/fork_choice_types.nim

@@ -103,7 +103,7 @@ type
     indices*: Table[Eth2Digest, Index]
     currentEpochTips*: Table[Index, FinalityCheckpoints]
     previousProposerBoostRoot*: Eth2Digest
-    previousProposerBoostScore*: uint64
+    previousProposerBoostScore*: Gwei
 
   ProtoNode* = object
     bid*: BlockId

beacon_chain/nimbus_beacon_node.nim

@@ -1204,16 +1204,17 @@ proc maybeUpdateActionTrackerNextEpoch(
       # functions get_flag_index_deltas() and get_inactivity_penalty_deltas().
       #
       # There are no penalties associated with TIMELY_HEAD_FLAG_INDEX, but a
-      # reward exists. effective_balance == MAX_EFFECTIVE_BALANCE ensures if
-      # even so, then the effective balance cannot change as a result.
+      # reward exists. effective_balance == MAX_EFFECTIVE_BALANCE.Gwei ensures
+      # if even so, then the effective balance cannot change as a result.
       #
       # It's not truly necessary to avoid all rewards and penalties, but only
       # to bound them to ensure they won't unexpected alter effective balance
       # during the upcoming epoch transition.
       #
-      # During genesis epoch, the check for epoch participation is against current,
-      # not previous, epoch, and therefore there's a possibility of checking for if
-      # a validator has participated in an epoch before it will happen.
+      # During genesis epoch, the check for epoch participation is against
+      # current, not previous, epoch, and therefore there's a possibility of
+      # checking for if a validator has participated in an epoch before it will
+      # happen.
       #
       # Because process_rewards_and_penalties() in epoch processing happens
       # before the current/previous participation swap, previous is correct
@@ -1234,7 +1235,7 @@ proc maybeUpdateActionTrackerNextEpoch(
 
       if  participation_flags.has_flag(TIMELY_SOURCE_FLAG_INDEX) and
           participation_flags.has_flag(TIMELY_TARGET_FLAG_INDEX) and
-          effective_balance == MAX_EFFECTIVE_BALANCE and
+          effective_balance == MAX_EFFECTIVE_BALANCE.Gwei and
           forkyState.data.slot.epoch != GENESIS_EPOCH and
           forkyState.data.inactivity_scores.item(
             nextEpochFirstProposer) == 0 and
@@ -1956,13 +1957,13 @@ proc start*(node: BeaconNode) {.raises: [CatchableError].} =
   node.elManager.start()
   node.run()
 
-func formatGwei(amount: uint64): string =
+func formatGwei(amount: Gwei): string =
   # TODO This is implemented in a quite a silly way.
   # Better routines for formatting decimal numbers
   # should exists somewhere else.
   let
-    eth = amount div 1000000000
-    remainder = amount mod 1000000000
+    eth = distinctBase(amount) div 1000000000
+    remainder = distinctBase(amount) mod 1000000000
 
   result = $eth
   if remainder != 0:

beacon_chain/rpc/rest_beacon_api.nim

@@ -100,10 +100,10 @@ proc getStatus(validator: Validator,
       ok(ValidatorFilterKind.ExitedSlashed)
   elif validator.withdrawable_epoch <= current_epoch:
     # withdrawal
-    if validator.effective_balance != 0:
+    if validator.effective_balance != 0.Gwei:
       ok(ValidatorFilterKind.WithdrawalPossible)
     else:
-      # validator.effective_balance == 0
+      # validator.effective_balance == 0.Gwei
       ok(ValidatorFilterKind.WithdrawalDone)
   else:
     err("Invalid validator status")

beacon_chain/spec/beaconstate.nim

@@ -29,22 +29,22 @@ func increase_balance*(balance: var Gwei, delta: Gwei) =
 func increase_balance*(
     state: var ForkyBeaconState, index: ValidatorIndex, delta: Gwei) =
   ## Increase the validator balance at index ``index`` by ``delta``.
-  if delta != 0: # avoid dirtying the balance cache if not needed
+  if delta != 0.Gwei: # avoid dirtying the balance cache if not needed
     increase_balance(state.balances.mitem(index), delta)
 
 # https://github.com/ethereum/consensus-specs/blob/v1.4.0-beta.6/specs/phase0/beacon-chain.md#decrease_balance
 func decrease_balance*(balance: var Gwei, delta: Gwei) =
   balance =
     if delta > balance:
-      0'u64
+      0.Gwei
     else:
       balance - delta
 
 func decrease_balance*(
     state: var ForkyBeaconState, index: ValidatorIndex, delta: Gwei) =
   ## Decrease the validator balance at index ``index`` by ``delta``, with
   ## underflow protection.
-  if delta != 0: # avoid dirtying the balance cache if not needed
+  if delta != 0.Gwei: # avoid dirtying the balance cache if not needed
     decrease_balance(state.balances.mitem(index), delta)
 
 # https://github.com/ethereum/consensus-specs/blob/v1.4.0-alpha.3/specs/phase0/beacon-chain.md#deposits
@@ -54,7 +54,8 @@ func get_validator_from_deposit*(deposit: DepositData):
   let
     amount = deposit.amount
     effective_balance = min(
-      amount - amount mod EFFECTIVE_BALANCE_INCREMENT, MAX_EFFECTIVE_BALANCE)
+      amount - amount mod EFFECTIVE_BALANCE_INCREMENT.Gwei,
+      MAX_EFFECTIVE_BALANCE.Gwei)
 
   Validator(
     pubkeyData: HashedValidatorPubKey.init(deposit.pubkey),
@@ -349,13 +350,13 @@ template get_total_balance(
   var res = 0.Gwei
   for validator_index in validator_indices:
     res += state.validators[validator_index].effective_balance
-  max(EFFECTIVE_BALANCE_INCREMENT, res)
+  max(EFFECTIVE_BALANCE_INCREMENT.Gwei, res)
 
 # https://github.com/ethereum/consensus-specs/blob/v1.4.0-beta.6/specs/phase0/beacon-chain.md#is_eligible_for_activation_queue
 func is_eligible_for_activation_queue*(validator: Validator): bool =
   ## Check if ``validator`` is eligible to be placed into the activation queue.
   validator.activation_eligibility_epoch == FAR_FUTURE_EPOCH and
-    validator.effective_balance == MAX_EFFECTIVE_BALANCE
+    validator.effective_balance == MAX_EFFECTIVE_BALANCE.Gwei
 
 # https://github.com/ethereum/consensus-specs/blob/v1.4.0-beta.6/specs/phase0/beacon-chain.md#is_eligible_for_activation
 func is_eligible_for_activation*(
@@ -619,11 +620,13 @@ func get_total_active_balance*(state: ForkyBeaconState, cache: var StateCache):
 # https://github.com/ethereum/consensus-specs/blob/v1.4.0/specs/altair/beacon-chain.md#get_base_reward_per_increment
 func get_base_reward_per_increment_sqrt(
     total_active_balance_sqrt: uint64): Gwei =
-  EFFECTIVE_BALANCE_INCREMENT * BASE_REWARD_FACTOR div total_active_balance_sqrt
+  EFFECTIVE_BALANCE_INCREMENT.Gwei * BASE_REWARD_FACTOR div
+    total_active_balance_sqrt
 
 func get_base_reward_per_increment*(
     total_active_balance: Gwei): Gwei =
-  get_base_reward_per_increment_sqrt(integer_squareroot(total_active_balance))
+  get_base_reward_per_increment_sqrt(
+    integer_squareroot(distinctBase(total_active_balance)))
 
 # https://github.com/ethereum/consensus-specs/blob/v1.4.0/specs/altair/beacon-chain.md#get_base_reward
 func get_base_reward(
@@ -633,7 +636,8 @@ func get_base_reward(
   ## Return the base reward for the validator defined by ``index`` with respect
   ## to the current ``state``.
   let increments =
-    state.validators[index].effective_balance div EFFECTIVE_BALANCE_INCREMENT
+    state.validators[index].effective_balance div
+    EFFECTIVE_BALANCE_INCREMENT.Gwei
   increments * base_reward_per_increment
 
 # https://github.com/ethereum/consensus-specs/blob/v1.4.0-beta.6/specs/phase0/beacon-chain.md#attestations
@@ -701,11 +705,12 @@ proc check_bls_to_execution_change*(
 
   ok()
 
-func get_proposer_reward*(state: ForkyBeaconState,
-                          attestation: SomeAttestation,
-                          base_reward_per_increment: Gwei,
-                          cache: var StateCache,
-                          epoch_participation: var EpochParticipationFlags): uint64 =
+func get_proposer_reward*(
+    state: ForkyBeaconState,
+    attestation: SomeAttestation,
+    base_reward_per_increment: Gwei,
+    cache: var StateCache,
+    epoch_participation: var EpochParticipationFlags): Gwei =
   let participation_flag_indices = get_attestation_participation_flag_indices(
     state, attestation.data, state.slot - attestation.data.slot)
   for index in get_attesting_indices_iter(
@@ -724,7 +729,7 @@ func get_proposer_reward*(state: ForkyBeaconState,
     (WEIGHT_DENOMINATOR.uint64 - PROPOSER_WEIGHT.uint64) *
     WEIGHT_DENOMINATOR.uint64 div PROPOSER_WEIGHT.uint64
 
-  return result div proposer_reward_denominator
+  result div proposer_reward_denominator
 
 proc process_attestation*(
     state: var ForkyBeaconState, attestation: SomeAttestation, flags: UpdateFlags,
@@ -811,7 +816,8 @@ func get_next_sync_committee_keys(
       candidate_index = active_validator_indices[shuffled_index]
       random_byte = eth2digest(hash_buffer).data[i mod 32]
       effective_balance = state.validators[candidate_index].effective_balance
-    if effective_balance * MAX_RANDOM_BYTE >= MAX_EFFECTIVE_BALANCE * random_byte:
+    if effective_balance * MAX_RANDOM_BYTE >=
+        MAX_EFFECTIVE_BALANCE.Gwei * random_byte:
       res[index] = state.validators[candidate_index].pubkey
       inc index
     i += 1'u64
@@ -827,16 +833,16 @@ func is_fully_withdrawable_validator(
     validator: Validator, balance: Gwei, epoch: Epoch): bool =
   ## Check if ``validator`` is fully withdrawable.
   has_eth1_withdrawal_credential(validator) and
-    validator.withdrawable_epoch <= epoch and balance > 0
+    validator.withdrawable_epoch <= epoch and balance > 0.Gwei
 
 # https://github.com/ethereum/consensus-specs/blob/v1.4.0-beta.5/specs/capella/beacon-chain.md#is_partially_withdrawable_validator
 func is_partially_withdrawable_validator(
     validator: Validator, balance: Gwei): bool =
   ## Check if ``validator`` is partially withdrawable.
   let
     has_max_effective_balance =
-      validator.effective_balance == MAX_EFFECTIVE_BALANCE
-    has_excess_balance = balance > MAX_EFFECTIVE_BALANCE
+      validator.effective_balance == MAX_EFFECTIVE_BALANCE.Gwei
+    has_excess_balance = balance > MAX_EFFECTIVE_BALANCE.Gwei
   has_eth1_withdrawal_credential(validator) and
     has_max_effective_balance and has_excess_balance
 
@@ -868,7 +874,7 @@ func get_expected_withdrawals*(
       var w = Withdrawal(
         index: withdrawal_index,
         validator_index: validator_index,
-        amount: balance - MAX_EFFECTIVE_BALANCE)
+        amount: balance - MAX_EFFECTIVE_BALANCE.Gwei)
       w.address.data[0..19] = validator.withdrawal_credentials.data[12..^1]
       withdrawals.add w
       withdrawal_index = WithdrawalIndex(withdrawal_index + 1)
@@ -974,9 +980,10 @@ proc initialize_beacon_state_from_eth1(
       validator = addr state.validators.mitem(vidx)
 
     validator.effective_balance = min(
-      balance - balance mod EFFECTIVE_BALANCE_INCREMENT, MAX_EFFECTIVE_BALANCE)
+      balance - balance mod EFFECTIVE_BALANCE_INCREMENT.Gwei,
+      MAX_EFFECTIVE_BALANCE.Gwei)
 
-    if validator.effective_balance == MAX_EFFECTIVE_BALANCE:
+    if validator.effective_balance == MAX_EFFECTIVE_BALANCE.Gwei:
       validator.activation_eligibility_epoch = GENESIS_EPOCH
       validator.activation_epoch = GENESIS_EPOCH
 
@@ -1091,9 +1098,10 @@ proc initialize_beacon_state_from_eth1*(
       validator = addr state.validators.mitem(vidx)
 
     validator.effective_balance = min(
-      balance - balance mod EFFECTIVE_BALANCE_INCREMENT, MAX_EFFECTIVE_BALANCE)
+      balance - balance mod EFFECTIVE_BALANCE_INCREMENT.Gwei,
+      MAX_EFFECTIVE_BALANCE.Gwei)
 
-    if validator.effective_balance == MAX_EFFECTIVE_BALANCE:
+    if validator.effective_balance == MAX_EFFECTIVE_BALANCE.Gwei:
       validator.activation_eligibility_epoch = GENESIS_EPOCH
       validator.activation_epoch = GENESIS_EPOCH
 

beacon_chain/spec/datatypes/base.nim

@@ -63,7 +63,7 @@
 import
   std/[macros, hashes, sets, strutils, tables, typetraits],
   results,
-  stew/[assign2, byteutils, endians2],
+  stew/[assign2, base10, byteutils, endians2],
   chronicles,
   json_serialization,
   ssz_serialization/types as sszTypes,
@@ -122,22 +122,39 @@ template maxSize*(n: int) {.pragma.}
 
 type
   Wei* = UInt256
-  Gwei* = uint64
+  Gwei* = distinct uint64
   Ether* = distinct uint64
 
 template ethAmountUnit*(typ: type) {.dirty.} =
-  # Arithmetic
   func `+`*(x, y: typ): typ {.borrow.}
   func `-`*(x, y: typ): typ {.borrow.}
   func `*`*(x: typ, y: distinctBase(typ)): typ {.borrow.}
   func `*`*(x: distinctBase(typ), y: typ): typ {.borrow.}
-
-  # Arithmetic, changing type
   func `div`*(x, y: typ): distinctBase(typ) {.borrow.}
+  func `div`*(x: typ, y: distinctBase(typ)): typ {.borrow.}
+  func `mod`*(x, y: typ): typ {.borrow.}
+
+  func `+=`*(x: var typ, y: typ) {.borrow.}
 
-  # Comparison
   func `<`*(x, y: typ): bool {.borrow.}
+  func `<=`*(x, y: typ): bool {.borrow.}
+  func `==`*(x, y: typ): bool {.borrow.}
+
+  func `$`*(x: typ): string {.borrow.}
+
+  func u256*(n: typ): UInt256 {.borrow.}
+
+  proc toString*(B: typedesc[Base10], value: typ): string {.borrow.}
+
+  proc writeValue*(writer: var JsonWriter, value: typ) {.raises: [IOError].} =
+    writer.writeValue(distinctBase(value))
+
+  proc readValue*(
+      reader: var JsonReader,
+      value: var typ) {.raises: [IOError, SerializationError].} =
+    reader.readValue(distinctBase(value))
 
+ethAmountUnit Gwei
 ethAmountUnit Ether
 
 type
@@ -758,8 +775,8 @@ template lenu64*(x: untyped): untyped =
 func `$`*(v: ForkDigest | Version | DomainType): string =
   toHex(distinctBase(v))
 
-func toGaugeValue*(x: uint64 | Epoch | Slot): int64 =
-  if x > uint64(int64.high):
+func toGaugeValue*[T: uint64 | Gwei | Slot | Epoch](x: T): int64 =
+  if x > uint64(int64.high).T:
     int64.high
   else:
     int64(x)

beacon_chain/spec/datatypes/capella.nim

@@ -557,7 +557,7 @@ type
 
     # Mod-increment
     randao_mix*: Eth2Digest
-    slashing*: uint64
+    slashing*: Gwei
 
     # Represent in full; for the next epoch, current_epoch_participation in
     # epoch n is previous_epoch_participation in epoch n+1 but this doesn't