Merge #17843: wallet: Reset reused transactions cache

6fc554f591d8ea1681b8bb25aa12da8d4f023f66 wallet: Reset reused transactions cache (Fabian Jahr)

Pull request description:

  Fixes #17603 (together with #17824)

  `getbalances` is using the cache within `GetAvailableCredit` under certain conditions [here](https://github.com/bitcoin/bitcoin/blob/35fff5be60e853455abc24713481544e91adfedb/src/wallet/wallet.cpp#L1826). For a wallet with `avoid_reuse` activated this can lead to inconsistent reporting of `used` transactions/balances between `getbalances` and `listunspent` as pointed out in #17603. When an address is reused before the first transaction is spending from this address, the cache is not updated even after the transaction is sent. This means the remaining outputs at the reused address are not showing up as `used` in `getbalances`.

  With this change, any newly incoming transaction belonging to the wallet marks all the other outputs at the same address as dirty.

ACKs for top commit:
  kallewoof:
    Code review re-ACK 6fc554f591d8ea1681b8bb25aa12da8d4f023f66
  promag:
    ACK 6fc554f591d8ea1681b8bb25aa12da8d4f023f66.
  achow101:
    Re-ACK 6fc554f591d8ea1681b8bb25aa12da8d4f023f66
  meshcollider:
    Code review ACK 6fc554f591d8ea1681b8bb25aa12da8d4f023f66

Tree-SHA512: c4cad2c752176d16d77b4a4202291d20baddf9f27250896a40274d74a6945e0f6b34be04c2f9b1b2e756d3ac669b794969df8f82a98e0b16f10e92f276649ea2

1 files changed, 32 insertions, 1 deletions

diff --git a/test/functional/wallet_avoidreuse.py b/test/functional/wallet_avoidreuse.py
index 6c0c06df73..1ca02a695c 100755
--- a/test/functional/wallet_avoidreuse.py
+++ b/test/functional/wallet_avoidreuse.py
@@ -91,7 +91,8 @@ class AvoidReuseTest(BitcoinTestFramework):
         self.test_fund_send_fund_send("p2sh-segwit")
         reset_balance(self.nodes[1], self.nodes[0].getnewaddress())
         self.test_fund_send_fund_send("bech32")
-
+        reset_balance(self.nodes[1], self.nodes[0].getnewaddress())
+        self.test_getbalances_used()
 
     def test_persistence(self):
         '''Test that wallet files persist the avoid_reuse flag.'''
@@ -257,5 +258,35 @@ class AvoidReuseTest(BitcoinTestFramework):
         assert_approx(self.nodes[1].getbalance(), 1, 0.001)
         assert_approx(self.nodes[1].getbalance(avoid_reuse=False), 11, 0.001)
 
+    def test_getbalances_used(self):
+        '''
+        getbalances and listunspent should pick up on reused addresses
+        immediately, even for address reusing outputs created before the first
+        transaction was spending from that address
+        '''
+        self.log.info("Test getbalances used category")
+
+        # node under test should be completely empty
+        assert_equal(self.nodes[1].getbalance(avoid_reuse=False), 0)
+
+        new_addr = self.nodes[1].getnewaddress()
+        ret_addr = self.nodes[0].getnewaddress()
+
+        # send multiple transactions, reusing one address
+        for _ in range(11):
+            self.nodes[0].sendtoaddress(new_addr, 1)
+
+        self.nodes[0].generate(1)
+        self.sync_all()
+
+        # send transaction that should not use all the available outputs
+        # per the current coin selection algorithm
+        self.nodes[1].sendtoaddress(ret_addr, 5)
+
+        # getbalances and listunspent should show the remaining outputs
+        # in the reused address as used/reused
+        assert_unspent(self.nodes[1], total_count=2, total_sum=6, reused_count=1, reused_sum=1)
+        assert_balances(self.nodes[1], mine={"used": 1, "trusted": 5})
+
 if __name__ == '__main__':
     AvoidReuseTest().main()