From 56954ec5089eaaa08423a453c6a44db3d8ce1457 Mon Sep 17 00:00:00 2001
From: Danny Ryan <dannyjryan@gmail.com>
Date: Fri, 23 Aug 2019 12:16:57 -0600
Subject: [PATCH] fix adding fields to phase 1 ssz objects

---
 specs/core/0_beacon-chain.md      |  2 --
 specs/core/1_beacon-chain-misc.md | 37 ++++++++++++++++++-------------
 2 files changed, 22 insertions(+), 17 deletions(-)

diff --git a/specs/core/0_beacon-chain.md b/specs/core/0_beacon-chain.md
index 5ddceebc1..90c179107 100644
--- a/specs/core/0_beacon-chain.md
+++ b/specs/core/0_beacon-chain.md
@@ -480,7 +480,6 @@ class BeaconBlockBody(Container):
     deposits: List[Deposit, MAX_DEPOSITS]
     voluntary_exits: List[VoluntaryExit, MAX_VOLUNTARY_EXITS]
     transfers: List[Transfer, MAX_TRANSFERS]
-    # @shard_receipts
 ```
 
 #### `BeaconBlock`
@@ -534,7 +533,6 @@ class BeaconState(Container):
     previous_justified_checkpoint: Checkpoint  # Previous epoch snapshot
     current_justified_checkpoint: Checkpoint
     finalized_checkpoint: Checkpoint
-    # @persistent_committee_fields
 ```
 
 ## Helper functions
diff --git a/specs/core/1_beacon-chain-misc.md b/specs/core/1_beacon-chain-misc.md
index b6f23a00e..65c4cdbbc 100644
--- a/specs/core/1_beacon-chain-misc.md
+++ b/specs/core/1_beacon-chain-misc.md
@@ -182,17 +182,32 @@ def process_shard_receipt_proof(state: BeaconState, receipt_proof: ShardReceiptP
 
 ## Changes
 
-### Persistent committees
+### Phase 0 container updates
 
-Add to the beacon state the following fields:
+Add the following fields to the end of the specified container objects.
+
+#### `BeaconState`
 
 ```python
-# begin insert @persistent_committee_fields
+class BeaconState(Container):
+    # Persistent committees
     persistent_committee_roots: Vector[Hash, PERSISTENT_COMMITTEE_ROOT_LENGTH]
     next_shard_receipt_period: Vector[uint64, SHARD_COUNT]
-# end insert @persistent_committee_fields
 ```
-`next_shard_receipt_period` values initialized to `PHASE_1_FORK_SLOT // SLOTS_PER_EPOCH // EPOCHS_PER_SHARD_PERIOD`
+
+`persistent_committee_roots` values are initialized to `Bytes32()` (empty bytes value).
+`next_shard_receipt_period` values are initialized to `PHASE_1_FORK_SLOT // SLOTS_PER_EPOCH // EPOCHS_PER_SHARD_PERIOD`.
+
+#### `BeaconBlockBody`
+
+```python
+class BeaconBlockBody(Container):
+    shard_receipt_proofs: List[ShardReceiptProof, MAX_SHARD_RECEIPT_PROOFS]
+```
+
+`shard_receipt_proofs` is initialized to `[]`.
+
+### Persistent committees
 
 Run `update_persistent_committee` immediately before `process_final_updates`:
 
@@ -215,18 +230,10 @@ def update_persistent_committee(state: BeaconState) -> None:
 
 ### Shard receipt processing
 
-Add the `shard_receipt_proofs` operation to `BeaconBlockBody`:
-
-```python
-# begin insert @shard_receipts
-    shard_receipt_proofs: List[ShardReceiptProof, MAX_SHARD_RECEIPT_PROOFS]
-# end insert @shard_receipts
-```
-
-Use `process_shard_receipt_proof` to process each receipt.
+Run `process_shard_receipt_proof` on each `ShardReceiptProof` during block processing.
 
 ```python
 # begin insert @process_shard_receipts
-        (body.shard_receipt_proofs, process_shard_receipt_proofs),
+        (body.shard_receipt_proofs, process_shard_receipt_proof),
 # end insert @process_shard_receipts
 ```