Merge bitcoin#24502: wallet: don't create long chains by default

da2bc86 [wallet] don't create long chains by default (glozow)

Pull request description:

  Default mempool policy doesn't let you have chains longer than 25 transactions. This is locally configurable of course, but it's not really safe to assume that a chain longer than 25 transactions will propagate. Thus, the wallet should probably avoid creating such transactions by default; set `DEFAULT_WALLET_REJECT_LONG_CHAINS` to true.

  Closes bitcoin#9752
  Closes bitcoin#10004

ACKs for top commit:
  MarcoFalke:
    re-ACK da2bc86 only change is fixing typos in tests 🎏

Tree-SHA512: 65d8e4ec437fe928adf554aa7e819a52e0599b403d5310895f4e371e99bbc838219b3097c4d2f775bc870ac617ef6b4227b94291f2b376f824f14e8f2b152f31

Author: MarcoFalke

src/wallet/wallet.h

@@ -94,7 +94,7 @@ static const CAmount WALLET_INCREMENTAL_RELAY_FEE = 5000;
 //! Default for -spendzeroconfchange
 static const bool DEFAULT_SPEND_ZEROCONF_CHANGE = true;
 //! Default for -walletrejectlongchains
-static const bool DEFAULT_WALLET_REJECT_LONG_CHAINS = false;
+static const bool DEFAULT_WALLET_REJECT_LONG_CHAINS{true};
 //! -txconfirmtarget default
 static const unsigned int DEFAULT_TX_CONFIRM_TARGET = 6;
 //! -walletrbf default

test/functional/wallet_balance.py

@@ -50,7 +50,9 @@ def set_test_params(self):
         self.num_nodes = 2
         self.setup_clean_chain = True
         self.extra_args = [
-            ['-limitdescendantcount=3'],  # Limit mempool descendants as a hack to have wallet txs rejected from the mempool
+            # Limit mempool descendants as a hack to have wallet txs rejected from the mempool.
+            # Set walletrejectlongchains=0 so the wallet still creates the transactions.
+            ['-limitdescendantcount=3', '-walletrejectlongchains=0'],
             [],
         ]
 

test/functional/wallet_basic.py

@@ -25,7 +25,7 @@ class WalletTest(BitcoinTestFramework):
     def set_test_params(self):
         self.num_nodes = 4
         self.extra_args = [[
-            "-acceptnonstdtxn=1",
+            "-acceptnonstdtxn=1", "-walletrejectlongchains=0"
         ]] * self.num_nodes
         self.setup_clean_chain = True
         self.supports_cli = False
@@ -142,7 +142,7 @@ def run_test(self):
         self.nodes[2].lockunspent(False, [unspent_0], True)
 
         # Restarting the node with the lock written to the wallet should keep the lock
-        self.restart_node(2)
+        self.restart_node(2, ["-walletrejectlongchains=0"])
         assert_raises_rpc_error(-8, "Invalid parameter, output already locked", self.nodes[2].lockunspent, False, [unspent_0])
 
         # Unloading and reloading the wallet with a persistent lock should keep the lock
@@ -568,7 +568,7 @@ def run_test(self):
         self.log.info("Test -reindex")
         self.stop_nodes()
         # set lower ancestor limit for later
-        self.start_node(0, ['-reindex', "-limitancestorcount=" + str(chainlimit)])
+        self.start_node(0, ['-reindex', "-walletrejectlongchains=0", "-limitancestorcount=" + str(chainlimit)])
         self.start_node(1, ['-reindex', "-limitancestorcount=" + str(chainlimit)])
         self.start_node(2, ['-reindex', "-limitancestorcount=" + str(chainlimit)])
         # reindex will leave rpc warm up "early"; Wait for it to finish