From d3a56be77a9d112cde4baef4314882170b9f228f Mon Sep 17 00:00:00 2001
From: Russell Yanofsky <russ@yanofsky.org>
Date: Thu, 2 Apr 2020 07:55:14 -0400
Subject: [PATCH] Revert "gui: Avoid Wallet::GetBalance in
 WalletModel::pollBalanceChanged"

This reverts commit 0933a37078e1ce3a3d70983c3e7f4b3ac6c3fa37 from
https://github.com/bitcoin/bitcoin/pull/18160 which no longer an optimization
since commit "gui: Avoid wallet tryGetBalances calls before TransactionChanged
or BlockTip notifications".
---
 src/interfaces/wallet.cpp |  3 +--
 src/interfaces/wallet.h   |  7 ++-----
 src/qt/walletmodel.cpp    | 17 ++++++++++-------
 3 files changed, 13 insertions(+), 14 deletions(-)

diff --git a/src/interfaces/wallet.cpp b/src/interfaces/wallet.cpp
index 752448aac7..3521ca8e38 100644
--- a/src/interfaces/wallet.cpp
+++ b/src/interfaces/wallet.cpp
@@ -351,14 +351,13 @@ public:
         }
         return result;
     }
-    bool tryGetBalances(WalletBalances& balances, int& num_blocks, bool force, int cached_num_blocks) override
+    bool tryGetBalances(WalletBalances& balances, int& num_blocks) override
     {
         TRY_LOCK(m_wallet->cs_wallet, locked_wallet);
         if (!locked_wallet) {
             return false;
         }
         num_blocks = m_wallet->GetLastBlockHeight();
-        if (!force && num_blocks == cached_num_blocks) return false;
         balances = getBalances();
         return true;
     }
diff --git a/src/interfaces/wallet.h b/src/interfaces/wallet.h
index e5e3b80663..0a437e53b9 100644
--- a/src/interfaces/wallet.h
+++ b/src/interfaces/wallet.h
@@ -201,11 +201,8 @@ public:
     //! Get balances.
     virtual WalletBalances getBalances() = 0;
 
-    //! Get balances if possible without waiting for chain and wallet locks.
-    virtual bool tryGetBalances(WalletBalances& balances,
-        int& num_blocks,
-        bool force,
-        int cached_num_blocks) = 0;
+    //! Get balances if possible without blocking.
+    virtual bool tryGetBalances(WalletBalances& balances, int& num_blocks) = 0;
 
     //! Get balance.
     virtual CAmount getBalance() = 0;
diff --git a/src/qt/walletmodel.cpp b/src/qt/walletmodel.cpp
index 1789fefead..28489cd210 100644
--- a/src/qt/walletmodel.cpp
+++ b/src/qt/walletmodel.cpp
@@ -95,18 +95,21 @@ void WalletModel::pollBalanceChanged()
     // rescan.
     interfaces::WalletBalances new_balances;
     int numBlocks = -1;
-    if (!m_wallet->tryGetBalances(new_balances, numBlocks, fForceCheckBalanceChanged, cachedNumBlocks)) {
+    if (!m_wallet->tryGetBalances(new_balances, numBlocks)) {
         return;
     }
 
-    fForceCheckBalanceChanged = false;
+    if(fForceCheckBalanceChanged || numBlocks != cachedNumBlocks)
+    {
+        fForceCheckBalanceChanged = false;
 
-    // Balance and number of transactions might have changed
-    cachedNumBlocks = numBlocks;
+        // Balance and number of transactions might have changed
+        cachedNumBlocks = numBlocks;
 
-    checkBalanceChanged(new_balances);
-    if(transactionTableModel)
-        transactionTableModel->updateConfirmations();
+        checkBalanceChanged(new_balances);
+        if(transactionTableModel)
+            transactionTableModel->updateConfirmations();
+    }
 }
 
 void WalletModel::checkBalanceChanged(const interfaces::WalletBalances& new_balances)