EIP-7251: format/lint fixes/docs, add validator guide

specs/_features/eip7251/beacon-chain.md

@@ -472,7 +472,6 @@ def queue_excess_active_balance(state: BeaconState, index: ValidatorIndex) -> No
 
 #### New `compute_exit_epoch_and_update_churn`
 
-
 ```python
 def compute_exit_epoch_and_update_churn(state: BeaconState, exit_balance: Gwei) -> Epoch:
     earliest_exit_epoch = compute_activation_exit_epoch(get_current_epoch(state))
@@ -570,12 +569,16 @@ def process_epoch(state: BeaconState) -> None:
 
 #### Updated  `process_registry_updates`
 
+`process_registry_updates` uses the updated definition of `initiate_validator_exit`
+and changes how the activation epochs are computed for eligible validators.
+
 ```python
 def process_registry_updates(state: BeaconState) -> None:
     # Process activation eligibility and ejections
     for index, validator in enumerate(state.validators):
         if is_eligible_for_activation_queue(validator):
             validator.activation_eligibility_epoch = get_current_epoch(state) + 1
+
         if (
             is_active_validator(validator, get_current_epoch(state))
             and validator.effective_balance <= EJECTION_BALANCE
@@ -607,7 +610,7 @@ def process_pending_balance_deposits(state: BeaconState) -> None:
     state.pending_balance_deposits = state.pending_balance_deposits[next_deposit_index:]
 
     if len(state.pending_balance_deposits) == 0:
-        state.deposit_balance_to_consume = 0
+        state.deposit_balance_to_consume = Gwei(0)
     else:
         state.deposit_balance_to_consume = available_for_processing - processed_amount
 ```
@@ -638,6 +641,8 @@ def process_pending_consolidations(state: BeaconState) -> None:
 
 #### Updated `process_effective_balance_updates`
 
+`process_effective_balance_updates` is updated with a new limit for the maximum effective balance.
+
 ```python
 def process_effective_balance_updates(state: BeaconState) -> None:
     # Update effective balances with hysteresis
@@ -779,14 +784,16 @@ def process_operations(state: BeaconState, body: BeaconBlockBody) -> None:
     for_ops(body.deposits, process_deposit)  # [Modified in EIP7251]
     for_ops(body.voluntary_exits, process_voluntary_exit)  # [Modified in EIP7251]
     for_ops(body.bls_to_execution_changes, process_bls_to_execution_change)
-    for_ops(body.execution_payload.withdraw_requests, process_execution_layer_withdraw_request)  # New in EIP7251
+    for_ops(body.execution_payload.withdraw_requests, process_execution_layer_withdraw_request)  # [New in EIP7251]
-    for_ops(body.consolidations, process_consolidation)  # New in EIP7251
+    for_ops(body.consolidations, process_consolidation)  # [New in EIP7251]
 ```
 
 ##### Deposits
 
 ###### Updated  `apply_deposit`
 
+*NOTE*: `process_deposit` is updated with a new definition of `apply_deposit`.
+
 ```python
 def apply_deposit(state: BeaconState,
                   pubkey: BLSPubkey,
@@ -819,7 +826,7 @@ def apply_deposit(state: BeaconState,
 def is_valid_deposit_signature(pubkey: BLSPubkey,
                                withdrawal_credentials: Bytes32,
                                amount: uint64,
-                               signature: BLSSignature) -> None:
+                               signature: BLSSignature) -> bool:
     deposit_message = DepositMessage(
         pubkey=pubkey,
         withdrawal_credentials=withdrawal_credentials,

specs/_features/eip7251/fork.md

@@ -131,8 +131,7 @@ def upgrade_to_eip7251(pre: deneb.BeaconState) -> BeaconState:
     # Ensure early adopters of compounding credentials go through the activation churn
     for index, validator in enumerate(post.validators):
         if has_compounding_withdrawal_credential(validator):
-            queue_excess_active_balance(post, index)
+            queue_excess_active_balance(post, ValidatorIndex(index))
 
     return post
 ```
-

specs/_features/eip7251/validator.md

@@ -0,0 +1,73 @@
+# EIP-7251 -- Honest Validator
+
+## Table of contents
+
+<!-- TOC -->
+<!-- START doctoc generated TOC please keep comment here to allow auto update -->
+<!-- DON'T EDIT THIS SECTION, INSTEAD RE-RUN doctoc TO UPDATE -->
+
+- [Introduction](#introduction)
+- [Prerequisites](#prerequisites)
+- [Beacon chain responsibilities](#beacon-chain-responsibilities)
+  - [Block and sidecar proposal](#block-and-sidecar-proposal)
+    - [Constructing the `BeaconBlockBody`](#constructing-the-beaconblockbody)
+      - [ExecutionPayload](#executionpayload)
+
+<!-- END doctoc generated TOC please keep comment here to allow auto update -->
+<!-- /TOC -->
+
+## Introduction
+
+This document represents the changes to be made in the code of an "honest validator".
+
+## Prerequisites
+
+This document is an extension of the [Deneb -- Honest Validator](../deneb/validator.md) guide.
+All behaviors and definitions defined in this document, and documents it extends, carry over unless explicitly noted or overridden.
+
+All terminology, constants, functions, and protocol mechanics defined in the updated [Beacon Chain doc of EIP-7251](./beacon-chain.md) are requisite for this document and used throughout.
+Please see related Beacon Chain doc before continuing and use them as a reference throughout.
+
+## Beacon chain responsibilities
+
+All validator responsibilities remain unchanged other than those noted below.
+
+### Block and sidecar proposal
+
+#### Constructing the `BeaconBlockBody`
+
+##### ExecutionPayload
+
+`prepare_execution_payload` is updated from the Deneb specs.
+
+*Note*: In this section, `state` is the state of the slot for the block proposal _without_ the block yet applied.
+That is, `state` is the `previous_state` processed through any empty slots up to the assigned slot using `process_slots(previous_state, slot)`.
+
+*Note*: The only change to `prepare_execution_payload` is the new definition of `get_expected_withdrawals`.
+
+```python
+def prepare_execution_payload(state: BeaconState,
+                              safe_block_hash: Hash32,
+                              finalized_block_hash: Hash32,
+                              suggested_fee_recipient: ExecutionAddress,
+                              execution_engine: ExecutionEngine) -> Optional[PayloadId]:
+    # Verify consistency of the parent hash with respect to the previous execution payload header
+    parent_hash = state.latest_execution_payload_header.block_hash
+
+    # Set the forkchoice head and initiate the payload build process
+    withdrawals, _ = get_expected_withdrawals(state)  # [Modified in EIP-7251]
+
+    payload_attributes = PayloadAttributes(
+        timestamp=compute_timestamp_at_slot(state, state.slot),
+        prev_randao=get_randao_mix(state, get_current_epoch(state)),
+        suggested_fee_recipient=suggested_fee_recipient,
+        withdrawals=withdrawals,
+        parent_beacon_block_root=hash_tree_root(state.latest_block_header),
+    )
+    return execution_engine.notify_forkchoice_updated(
+        head_block_hash=parent_hash,
+        safe_block_hash=safe_block_hash,
+        finalized_block_hash=finalized_block_hash,
+        payload_attributes=payload_attributes,
+    )
+```