From 7e89994133725125dddbfa8d45484e3b9ed51c6e Mon Sep 17 00:00:00 2001
From: Antoine Riard <ariard@student.42.fr>
Date: Thu, 15 Aug 2019 11:42:16 -0400
Subject: [PATCH] Remove SyncTransaction for conflicted txn in
 CWallet::BlockConnected

We shouldn't rely on this sync call to get an accurate view of txn
state, if a tx conflicts with one in mapTx we are going to update
our wallet dependencies in AddToWalletIfInvolvingMe while conflicting
txn get connected. If it doesn't conflict with one of our dependencies
we are not going to track it anyway.

This is a cleanup, as this SyncTransaction is redundant with the
following one for confirmation which is triggering the MarkConflicted
logic. We keep the loop because set of conflicted txn isn't same as txn
included in block.
---
 src/wallet/wallet.cpp | 14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 098f7990ad..8b636c41a2 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -1410,22 +1410,14 @@ void CWallet::BlockConnected(const CBlock& block, const std::vector<CTransaction
     const uint256& block_hash = block.GetHash();
     auto locked_chain = chain().lock();
     LOCK(cs_wallet);
-    // TODO: Temporarily ensure that mempool removals are notified before
-    // connected transactions.  This shouldn't matter, but the abandoned
-    // state of transactions in our wallet is currently cleared when we
-    // receive another notification and there is a race condition where
-    // notification of a connected conflict might cause an outside process
-    // to abandon a transaction and then have it inadvertently cleared by
-    // the notification that the conflicted transaction was evicted.
 
-    for (const CTransactionRef& ptx : vtxConflicted) {
-        SyncTransaction(ptx, CWalletTx::Status::CONFLICTED, {} /* block hash */, 0 /* position in block */);
-        TransactionRemovedFromMempool(ptx);
-    }
     for (size_t i = 0; i < block.vtx.size(); i++) {
         SyncTransaction(block.vtx[i], CWalletTx::Status::CONFIRMED, block_hash, i);
         TransactionRemovedFromMempool(block.vtx[i]);
     }
+    for (const CTransactionRef& ptx : vtxConflicted) {
+        TransactionRemovedFromMempool(ptx);
+    }
 
     m_last_block_processed = block_hash;
 }