From 3ed0619951dd43b30ed69e96baf0aa9bbb5a1f5f Mon Sep 17 00:00:00 2001
From: Suphanat Chunhapanya <haxx.pop@gmail.com>
Date: Tue, 11 Jul 2023 15:47:17 +0700
Subject: [PATCH 1/2] Update the equivocating indices in the store

Since we sometimes reuse the slashed validator index, we need to remove
it from the list of equivocating indices in the fork-choice store.
---
 specs/_features/eip6914/beacon-chain.md |  2 +-
 specs/_features/eip6914/fork-choice.md  | 36 +++++++++++++++++++++++++
 2 files changed, 37 insertions(+), 1 deletion(-)
 create mode 100644 specs/_features/eip6914/fork-choice.md

diff --git a/specs/_features/eip6914/beacon-chain.md b/specs/_features/eip6914/beacon-chain.md
index 2c60c9bdb..1e0b20747 100644
--- a/specs/_features/eip6914/beacon-chain.md
+++ b/specs/_features/eip6914/beacon-chain.md
@@ -1,4 +1,4 @@
-EIP-6914 -- The Beacon Chain
+# EIP-6914 -- The Beacon Chain
 
 ## Table of contents
 
diff --git a/specs/_features/eip6914/fork-choice.md b/specs/_features/eip6914/fork-choice.md
new file mode 100644
index 000000000..e422a8e37
--- /dev/null
+++ b/specs/_features/eip6914/fork-choice.md
@@ -0,0 +1,36 @@
+# EIP-6914 -- Fork Choice
+
+## 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)
+- [Fork choice](#fork-choice)
+  - [Handlers](#handlers)
+    - [`on_reused_index`](#on_reused_index)
+
+<!-- END doctoc generated TOC please keep comment here to allow auto update -->
+<!-- /TOC -->
+
+## Introduction
+
+This is the modification of the fork choice according to EIP-6914.
+
+## Fork choice
+
+A new handler is added with this upgrade:
+
+- `on_reused_index(store, index)` whenever a validator index `index: ValidatorIndex` is reused
+
+This new handler is used to update the list of equivocating indices to be synchronized with the canonical chain.
+
+### Handlers
+
+#### `on_reused_index`
+
+```python
+def on_reused_index(store: Store, index: ValidatorIndex) -> None:
+    store.equivocating_indices.discard(index)
+```

From d8b023c5d8099db2459aec15985a0ffd9e2a24c2 Mon Sep 17 00:00:00 2001
From: Suphanat Chunhapanya <haxx.pop@gmail.com>
Date: Tue, 18 Jul 2023 19:55:18 +0700
Subject: [PATCH 2/2] Explain more on on_reused_index

---
 specs/_features/eip6914/fork-choice.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/specs/_features/eip6914/fork-choice.md b/specs/_features/eip6914/fork-choice.md
index e422a8e37..25adc82d6 100644
--- a/specs/_features/eip6914/fork-choice.md
+++ b/specs/_features/eip6914/fork-choice.md
@@ -22,7 +22,7 @@ This is the modification of the fork choice according to EIP-6914.
 
 A new handler is added with this upgrade:
 
-- `on_reused_index(store, index)` whenever a validator index `index: ValidatorIndex` is reused
+- `on_reused_index(store, index)` whenever a validator index `index: ValidatorIndex` is reused. That is, [`get_index_for_new_validator()`](./beacon-chain.md#get_index_for_new_validator) provides an index due to a return value of `True` from [`is_reusable_validator()`](./beacon-chain.md#is_reusable_validator).
 
 This new handler is used to update the list of equivocating indices to be synchronized with the canonical chain.