From f0a8e392434fa06e96b84249c4dd9533d8012cfb Mon Sep 17 00:00:00 2001
From: Justin Drake <drakefjustin@gmail.com>
Date: Sat, 29 Jun 2019 17:29:21 +0100
Subject: [PATCH] WIP

---
 specs/core/0_beacon-chain.md                  |  4 +-
 .../pyspec/eth2spec/test/helpers/deposits.py  | 40 ++++++++-----------
 2 files changed, 19 insertions(+), 25 deletions(-)

diff --git a/specs/core/0_beacon-chain.md b/specs/core/0_beacon-chain.md
index 6f28c0e3d..138d3fd2a 100644
--- a/specs/core/0_beacon-chain.md
+++ b/specs/core/0_beacon-chain.md
@@ -437,7 +437,7 @@ class Attestation(Container):
 
 ```python
 class Deposit(Container):
-    proof: Vector[Hash, DEPOSIT_CONTRACT_TREE_DEPTH]  # Merkle path to deposit root
+    proof: Vector[Hash, DEPOSIT_CONTRACT_TREE_DEPTH + 1]  # Merkle path to deposit root
     data: DepositData
 ```
 
@@ -1682,7 +1682,7 @@ def process_deposit(state: BeaconState, deposit: Deposit) -> None:
     assert verify_merkle_branch(
         leaf=hash_tree_root(deposit.data),
         proof=deposit.proof,
-        depth=DEPOSIT_CONTRACT_TREE_DEPTH,
+        depth=DEPOSIT_CONTRACT_TREE_DEPTH + 1,
         index=state.eth1_deposit_index,
         root=state.eth1_data.deposit_root,
     )
diff --git a/test_libs/pyspec/eth2spec/test/helpers/deposits.py b/test_libs/pyspec/eth2spec/test/helpers/deposits.py
index 20ff7440f..5a0909185 100644
--- a/test_libs/pyspec/eth2spec/test/helpers/deposits.py
+++ b/test_libs/pyspec/eth2spec/test/helpers/deposits.py
@@ -1,11 +1,13 @@
 from eth2spec.test.helpers.keys import pubkeys, privkeys
 from eth2spec.utils.bls import bls_sign
 from eth2spec.utils.merkle_minimal import calc_merkle_tree_from_leaves, get_merkle_root, get_merkle_proof
-from eth2spec.utils.ssz.ssz_impl import signing_root
+from eth2spec.utils.ssz.ssz_impl import signing_root, hash_tree_root
+from eth2spec.utils.ssz.ssz_typing import List
+from eth2spec.phase0.spec import DepositData
 
 
 def build_deposit_data(spec, state, pubkey, privkey, amount, withdrawal_credentials, signed=False):
-    deposit_data = spec.DepositData(
+    deposit_data = DepositData(
         pubkey=pubkey,
         withdrawal_credentials=withdrawal_credentials,
         amount=amount,
@@ -29,27 +31,21 @@ def sign_deposit_data(spec, state, deposit_data, privkey):
 
 def build_deposit(spec,
                   state,
-                  deposit_data_leaves,
+                  deposit_data_list,
                   pubkey,
                   privkey,
                   amount,
                   withdrawal_credentials,
                   signed):
     deposit_data = build_deposit_data(spec, state, pubkey, privkey, amount, withdrawal_credentials, signed)
-
-    item = deposit_data.hash_tree_root()
-    index = len(deposit_data_leaves)
-    deposit_data_leaves.append(item)
-    tree = calc_merkle_tree_from_leaves(tuple(deposit_data_leaves))
-    root = get_merkle_root((tuple(deposit_data_leaves)))
-    proof = list(get_merkle_proof(tree, item_index=index))
-    assert spec.verify_merkle_branch(item, proof, spec.DEPOSIT_CONTRACT_TREE_DEPTH, index, root)
-
-    deposit = spec.Deposit(
-        proof=list(proof),
-        index=index,
-        data=deposit_data,
-    )
+    deposit_data_list.append(deposit_data)
+    index = len(deposit_data_list)
+    root = hash_tree_root(List[DepositData, 2**32](*deposit_data_list))
+    tree = calc_merkle_tree_from_leaves(tuple([d.hash_tree_root() for d in deposit_data_list]))
+    proof = list(get_merkle_proof(tree, item_index=index)) + [index.to_bytes(32, 'little')]
+    leaf = deposit_data.hash_tree_root()
+    assert spec.verify_merkle_branch(leaf, proof, spec.DEPOSIT_CONTRACT_TREE_DEPTH + 1, index, root)
+    deposit = spec.Deposit(proof, index, deposit_data)
 
     return deposit, root, deposit_data_leaves
 
@@ -58,9 +54,7 @@ def prepare_state_and_deposit(spec, state, validator_index, amount, withdrawal_c
     """
     Prepare the state for the deposit, and create a deposit for the given validator, depositing the given amount.
     """
-    pre_validator_count = len(state.validators)
-    # fill previous deposits with zero-hash
-    deposit_data_leaves = [spec.ZERO_HASH] * pre_validator_count
+    deposit_data_list = []
 
     pubkey = pubkeys[validator_index]
     privkey = privkeys[validator_index]
@@ -69,10 +63,10 @@ def prepare_state_and_deposit(spec, state, validator_index, amount, withdrawal_c
     if withdrawal_credentials is None:
         withdrawal_credentials = spec.int_to_bytes(spec.BLS_WITHDRAWAL_PREFIX, length=1) + spec.hash(pubkey)[1:]
 
-    deposit, root, deposit_data_leaves = build_deposit(
+    deposit, root, deposit_data_list = build_deposit(
         spec,
         state,
-        deposit_data_leaves,
+        deposit_data_list,
         pubkey,
         privkey,
         amount,
@@ -81,5 +75,5 @@ def prepare_state_and_deposit(spec, state, validator_index, amount, withdrawal_c
     )
 
     state.eth1_data.deposit_root = root
-    state.eth1_data.deposit_count = len(deposit_data_leaves)
+    state.eth1_data.deposit_count = len(deposit_data_list)
     return deposit