Merge #16898: test: Remove connect_nodes_bi

fadfd844de8c53034a97dfa6f771ffe9f523fba2 test: Remove unused connect_nodes_bi (MarcoFalke)
fa3b9ee8b2280af4bcbcfffff275aaf8dd125929 scripted-diff: test: Replace connect_nodes_bi with connect_nodes (MarcoFalke)
faaee1e39a91b3f603881655d3980c29af09852b test: Use connect_nodes when connecting nodes in the test_framework (MarcoFalke)
1111bb91f517838e5b9f778bf6b5a9c8d561e857 test: Reformat python imports to aid scripted diff (MarcoFalke)

Pull request description:

  By default all test nodes are connected in a chain. However, instead of just a single connection between each pair of nodes, we end up with up to four connections for a "middle" node (two outbound, two inbound, from each side).

  This is generally redundant (tx and block relay should succeed with just a single connection) and confusing. For example, test timeouts after a call to `sync_` may be racy and hard to reproduce. On top of that, the test `debug.log`s are hard to read because txs and block invs may be relayed on the same connection multiple times.

  Fix this by inlining `connect_nodes_bi` in the two tests that need it, and then replace it with a single `connect_nodes` in all other tests.

  Historic background:

  `connect_nodes_bi` has been introduced as a (temporary?) workaround for bug #5113 and #5138, which has long been fixed in #5157 and #5662.

ACKs for top commit:
  laanwj:
    ACK fadfd844de8c53034a97dfa6f771ffe9f523fba2
  jonasschnelli:
    utACK fadfd844de8c53034a97dfa6f771ffe9f523fba2 - more of less a cleanup PR.
  promag:
    Tested ACK fadfd844de8c53034a97dfa6f771ffe9f523fba2, ran extended tests.

Tree-SHA512: 2d027a8fd150749c071b64438a0a78ec922178628a7dbb89fd1212b0fa34febd451798c940101155d3617c0426c2c4865174147709894f1f1bb6cfa336aa7e24

test/functional/feature_notifications.py

@@ -7,7 +7,11 @@ import os
 
 from test_framework.address import ADDRESS_BCRT1_UNSPENDABLE
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import assert_equal, wait_until, connect_nodes_bi
+from test_framework.util import (
+    assert_equal,
+    wait_until,
+    connect_nodes,
+)
 
 
 class NotificationsTest(BitcoinTestFramework):
@@ -59,7 +63,7 @@ class NotificationsTest(BitcoinTestFramework):
             self.log.info("test -walletnotify after rescan")
             # restart node to rescan to force wallet notifications
             self.start_node(1)
-            connect_nodes_bi(self.nodes, 0, 1)
+            connect_nodes(self.nodes[0], 1)
 
             wait_until(lambda: len(os.listdir(self.walletnotify_dir)) == block_count, timeout=10)
 

test/functional/p2p_connect_to_devnet.py

@@ -6,7 +6,7 @@
 
 from test_framework.mininode import P2PInterface
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import assert_equal, connect_nodes_bi
+from test_framework.util import assert_equal, connect_nodes
 
 class ConnectDevnetNodes(BitcoinTestFramework):
     def set_test_params(self):
@@ -18,13 +18,13 @@ class ConnectDevnetNodes(BitcoinTestFramework):
         self.add_nodes(self.num_nodes)
         self.start_node(0)
         self.start_node(1)
-        connect_nodes_bi(self.nodes, 0, 1)
+        connect_nodes(self.nodes[0], 1)
         self.sync_all()
 
 
     def run_test(self):
         self.nodes[0].add_p2p_connection(P2PInterface())
-        assert_equal(self.nodes[0].getconnectioncount(), 3)  # 2 in/out dashd + 1 p2p
+        assert_equal(self.nodes[0].getconnectioncount(), 2)  # 1 out dashd + 1 p2p
 
 
 if __name__ == '__main__':

test/functional/p2p_disconnect_ban.py

@@ -8,7 +8,7 @@ from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import (
     assert_equal,
     assert_raises_rpc_error,
-    connect_nodes_bi,
+    connect_nodes,
     wait_until,
 )
 
@@ -17,6 +17,10 @@ class DisconnectBanTest(BitcoinTestFramework):
         self.num_nodes = 2
 
     def run_test(self):
+        self.log.info("Connect nodes both way")
+        connect_nodes(self.nodes[0], 1)
+        connect_nodes(self.nodes[1], 0)
+
         self.log.info("Test setban and listbanned RPCs")
 
         self.log.info("setban: successfully ban single IP address")
@@ -69,7 +73,9 @@ class DisconnectBanTest(BitcoinTestFramework):
 
         # Clear ban lists
         self.nodes[1].clearbanned()
-        connect_nodes_bi(self.nodes, 0, 1)
+        self.log.info("Connect nodes both way")
+        connect_nodes(self.nodes[0], 1)
+        connect_nodes(self.nodes[1], 0)
 
         self.log.info("Test disconnectnode RPCs")
 
@@ -88,7 +94,7 @@ class DisconnectBanTest(BitcoinTestFramework):
         assert not [node for node in self.nodes[0].getpeerinfo() if node['addr'] == address1]
 
         self.log.info("disconnectnode: successfully reconnect node")
-        connect_nodes_bi(self.nodes, 0, 1)  # reconnect the node
+        connect_nodes(self.nodes[0], 1)  # reconnect the node
         assert_equal(len(self.nodes[0].getpeerinfo()), 2)
         assert [node for node in self.nodes[0].getpeerinfo() if node['addr'] == address1]
 

test/functional/p2p_node_network_limited.py

@@ -11,7 +11,7 @@ and that it responds to getdata requests for blocks correctly:
 from test_framework.messages import CInv, msg_getdata, NODE_BLOOM, NODE_NETWORK_LIMITED, msg_verack
 from test_framework.mininode import P2PInterface, mininode_lock
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import assert_equal, disconnect_nodes, connect_nodes_bi, sync_blocks, wait_until
+from test_framework.util import assert_equal, disconnect_nodes, connect_nodes, sync_blocks, wait_until
 
 class P2PIgnoreInv(P2PInterface):
     firstAddrnServices = 0
@@ -58,7 +58,7 @@ class NodeNetworkLimitedTest(BitcoinTestFramework):
         assert_equal(int(self.nodes[0].getnetworkinfo()['localservices'], 16), expected_services)
 
         self.log.info("Mine enough blocks to reach the NODE_NETWORK_LIMITED range.")
-        connect_nodes_bi(self.nodes, 0, 1)
+        connect_nodes(self.nodes[0], 1)
         blocks = self.nodes[1].generatetoaddress(292, self.nodes[1].get_deterministic_priv_key().address)
         sync_blocks([self.nodes[0], self.nodes[1]])
 
@@ -84,7 +84,7 @@ class NodeNetworkLimitedTest(BitcoinTestFramework):
 
         # connect unsynced node 2 with pruned NODE_NETWORK_LIMITED peer
         # because node 2 is in IBD and node 0 is a NODE_NETWORK_LIMITED peer, sync must not be possible
-        connect_nodes_bi(self.nodes, 0, 2)
+        connect_nodes(self.nodes[0], 2)
         try:
             sync_blocks([self.nodes[0], self.nodes[2]], timeout=5)
         except:
@@ -93,7 +93,7 @@ class NodeNetworkLimitedTest(BitcoinTestFramework):
         assert_equal(self.nodes[2].getblockheader(self.nodes[2].getbestblockhash())['height'], 0)
 
         # now connect also to node 1 (non pruned)
-        connect_nodes_bi(self.nodes, 1, 2)
+        connect_nodes(self.nodes[1], 2)
 
         # sync must be possible
         sync_blocks(self.nodes)
@@ -105,7 +105,7 @@ class NodeNetworkLimitedTest(BitcoinTestFramework):
         self.nodes[0].generatetoaddress(10, self.nodes[0].get_deterministic_priv_key().address)
 
         # connect node1 (non pruned) with node0 (pruned) and check if the can sync
-        connect_nodes_bi(self.nodes, 0, 1)
+        connect_nodes(self.nodes[0], 1)
 
         # sync must be possible, node 1 is no longer in IBD and should therefore connect to node 0 (NODE_NETWORK_LIMITED)
         sync_blocks([self.nodes[0], self.nodes[1]])

test/functional/rpc_fundrawtransaction.py

@@ -12,7 +12,7 @@ from test_framework.util import (
     assert_greater_than,
     assert_greater_than_or_equal,
     assert_raises_rpc_error,
-    connect_nodes_bi,
+    connect_nodes,
     count_bytes,
     find_vout_for_address,
 )
@@ -36,10 +36,10 @@ class RawTransactionsTest(BitcoinTestFramework):
     def setup_network(self):
         self.setup_nodes()
 
-        connect_nodes_bi(self.nodes, 0, 1)
+        connect_nodes(self.nodes[0], 1)
-        connect_nodes_bi(self.nodes, 1, 2)
+        connect_nodes(self.nodes[1], 2)
-        connect_nodes_bi(self.nodes, 0, 2)
+        connect_nodes(self.nodes[0], 2)
-        connect_nodes_bi(self.nodes, 0, 3)
+        connect_nodes(self.nodes[0], 3)
 
     def run_test(self):
         min_relay_tx_fee = self.nodes[0].getnetworkinfo()['relayfee']
@@ -475,10 +475,10 @@ class RawTransactionsTest(BitcoinTestFramework):
         for node in self.nodes:
             node.settxfee(min_relay_tx_fee)
 
-        connect_nodes_bi(self.nodes,0,1)
+        connect_nodes(self.nodes[0], 1)
-        connect_nodes_bi(self.nodes,1,2)
+        connect_nodes(self.nodes[1], 2)
-        connect_nodes_bi(self.nodes,0,2)
+        connect_nodes(self.nodes[0], 2)
-        connect_nodes_bi(self.nodes,0,3)
+        connect_nodes(self.nodes[0], 3)
         # Again lock the watchonly UTXO or nodes[0] may spend it, because
         # lockunspent is memory-only and thus lost on restart
         self.nodes[0].lockunspent(False, [{"txid": watchonly_txid, "vout": watchonly_vout}])

test/functional/rpc_fundrawtransaction_hd.py

@@ -7,7 +7,7 @@ from decimal import Decimal
 
 from test_framework.authproxy import JSONRPCException
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import assert_equal, assert_greater_than, connect_nodes_bi
+from test_framework.util import assert_equal, assert_greater_than, connect_nodes
 
 # Create one-input, one-output, no-fee transaction:
 class RawTransactionsTest(BitcoinTestFramework):
@@ -22,10 +22,10 @@ class RawTransactionsTest(BitcoinTestFramework):
 
     def setup_network(self):
         super().setup_network()
-        connect_nodes_bi(self.nodes,0,1)
+        connect_nodes(self.nodes[0],1)
-        connect_nodes_bi(self.nodes,1,2)
+        connect_nodes(self.nodes[1],2)
-        connect_nodes_bi(self.nodes,0,2)
+        connect_nodes(self.nodes[0],2)
-        connect_nodes_bi(self.nodes,0,3)
+        connect_nodes(self.nodes[0],3)
 
     def run_test(self):
         self.log.info("Mining blocks...")
@@ -451,10 +451,10 @@ class RawTransactionsTest(BitcoinTestFramework):
         for node in self.nodes:
             node.settxfee(min_relay_tx_fee)
 
-        connect_nodes_bi(self.nodes,0,1)
+        connect_nodes(self.nodes[0],1)
-        connect_nodes_bi(self.nodes,1,2)
+        connect_nodes(self.nodes[1],2)
-        connect_nodes_bi(self.nodes,0,2)
+        connect_nodes(self.nodes[0],2)
-        connect_nodes_bi(self.nodes,0,3)
+        connect_nodes(self.nodes[0],3)
         self.sync_all()
 
         # drain the keypool

test/functional/rpc_net.py

@@ -13,7 +13,7 @@ from test_framework.util import (
     assert_greater_than_or_equal,
     assert_greater_than,
     assert_raises_rpc_error,
-    connect_nodes_bi,
+    connect_nodes,
     p2p_port,
     wait_until,
 )
@@ -50,13 +50,16 @@ class NetTest(BitcoinTestFramework):
     def setup_network(self):
         self.disable_mocktime()
         self.setup_nodes()
-        connect_nodes_bi(self.nodes, 0, 1)
+        connect_nodes(self.nodes[0], 1)
 
     def run_test(self):
         # Wait for one ping/pong to finish so that we can be sure that there is no chatter between nodes for some time
         # Especially the exchange of messages like getheaders and friends causes test failures here
         self.nodes[0].ping()
         wait_until(lambda: all(['pingtime' in n for n in self.nodes[0].getpeerinfo()]))
+        self.log.info('Connect nodes both way')
+        connect_nodes(self.nodes[0], 1)
+        connect_nodes(self.nodes[1], 0)
 
         self._test_connection_count()
         self._test_getnettotals()
@@ -66,7 +69,7 @@ class NetTest(BitcoinTestFramework):
         self._test_getnodeaddresses()
 
     def _test_connection_count(self):
-        # connect_nodes_bi connects each node to the other
+        # connect_nodes connects each node to the other
         assert_equal(self.nodes[0].getconnectioncount(), 2)
 
     def _test_getnettotals(self):
@@ -110,7 +113,10 @@ class NetTest(BitcoinTestFramework):
         wait_until(lambda: self.nodes[1].getnetworkinfo()['connections'] == 0, timeout=3)
 
         self.nodes[0].setnetworkactive(state=True)
-        connect_nodes_bi(self.nodes, 0, 1)
+        self.log.info('Connect nodes both way')
+        connect_nodes(self.nodes[0], 1)
+        connect_nodes(self.nodes[1], 0)
+
         assert_equal(self.nodes[0].getnetworkinfo()['networkactive'], True)
         assert_equal(self.nodes[0].getnetworkinfo()['connections'], 2)
 

test/functional/rpc_preciousblock.py

@@ -7,7 +7,7 @@
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import (
     assert_equal,
-    connect_nodes_bi,
+    connect_nodes,
     sync_blocks,
 )
 
@@ -61,7 +61,7 @@ class PreciousTest(BitcoinTestFramework):
         self.log.info("Connect nodes and check no reorg occurs")
         # Submit competing blocks via RPC so any reorg should occur before we proceed (no way to wait on inaction for p2p sync)
         node_sync_via_rpc(self.nodes[0:2])
-        connect_nodes_bi(self.nodes,0,1)
+        connect_nodes(self.nodes[0], 1)
         assert_equal(self.nodes[0].getbestblockhash(), hashC)
         assert_equal(self.nodes[1].getbestblockhash(), hashG)
         self.log.info("Make Node0 prefer block G")
@@ -98,8 +98,8 @@ class PreciousTest(BitcoinTestFramework):
         hashL = self.nodes[2].getbestblockhash()
         self.log.info("Connect nodes and check no reorg occurs")
         node_sync_via_rpc(self.nodes[1:3])
-        connect_nodes_bi(self.nodes,1,2)
+        connect_nodes(self.nodes[1], 2)
-        connect_nodes_bi(self.nodes,0,2)
+        connect_nodes(self.nodes[0], 2)
         assert_equal(self.nodes[0].getbestblockhash(), hashH)
         assert_equal(self.nodes[1].getbestblockhash(), hashH)
         assert_equal(self.nodes[2].getbestblockhash(), hashL)

test/functional/rpc_rawtransaction.py

@@ -17,7 +17,13 @@ from decimal import Decimal
 from io import BytesIO
 from test_framework.messages import CTransaction, ToHex
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import assert_equal, assert_raises_rpc_error, connect_nodes_bi, hex_str_to_bytes
+from test_framework.util import (
+    assert_equal,
+    assert_raises_rpc_error,
+    connect_nodes,
+    hex_str_to_bytes,
+)
+
 
 class multidict(dict):
     """Dictionary that allows duplicate keys.
@@ -53,7 +59,7 @@ class RawTransactionsTest(BitcoinTestFramework):
 
     def setup_network(self):
         super().setup_network()
-        connect_nodes_bi(self.nodes, 0, 2)
+        connect_nodes(self.nodes[0], 2)
 
     def run_test(self):
         self.log.info('prepare some coins for multiple *rawtransaction commands')

test/functional/test_framework/test_framework.py

@@ -37,7 +37,6 @@ from .util import (
     MAX_NODES,
     assert_equal,
     check_json_precision,
-    connect_nodes_bi,
     connect_nodes,
     copy_datadir,
     disconnect_nodes,
@@ -326,8 +325,18 @@ class BitcoinTestFramework(metaclass=BitcoinTestMetaClass):
         # Connect the nodes as a "chain".  This allows us
         # to split the network between nodes 1 and 2 to get
         # two halves that can work on competing chains.
+        #
+        # Topology looks like this:
+        # node0 <-- node1 <-- node2 <-- node3
+        #
+        # If all nodes are in IBD (clean chain from genesis), node0 is assumed to be the source of blocks (miner). To
+        # ensure block propagation, all nodes will establish outgoing connections toward node0.
+        # See fPreferredDownload in net_processing.
+        #
+        # If further outbound connections are needed, they can be added at the beginning of the test with e.g.
+        # connect_nodes(self.nodes[1], 2)
         for i in range(self.num_nodes - 1):
-            connect_nodes_bi(self.nodes, i, i + 1)
+            connect_nodes(self.nodes[i + 1], i)
         self.sync_all()
 
     def setup_nodes(self):
@@ -459,7 +468,7 @@ class BitcoinTestFramework(metaclass=BitcoinTestMetaClass):
         """
         Join the (previously split) network halves together.
         """
-        connect_nodes_bi(self.nodes, 1, 2)
+        connect_nodes(self.nodes[1], 2)
         self.sync_all()
 
     def sync_blocks(self, nodes=None, **kwargs):

test/functional/test_framework/util.py

@@ -445,10 +445,6 @@ def connect_nodes(from_connection, node_num):
     wait_until(lambda: all(peer['version'] != 0 for peer in from_connection.getpeerinfo()))
     wait_until(lambda: all(peer['bytesrecv_per_msg'].pop('verack', 0) == 24 for peer in from_connection.getpeerinfo()))
 
-def connect_nodes_bi(nodes, a, b):
-    connect_nodes(nodes[a], b)
-    connect_nodes(nodes[b], a)
-
 def isolate_node(node, timeout=5):
     node.setnetworkactive(False)
     st = time.time()

test/functional/wallet_basic.py

@@ -12,7 +12,7 @@ from test_framework.util import (
     assert_equal,
     assert_fee_amount,
     assert_raises_rpc_error,
-    connect_nodes_bi,
+    connect_nodes,
     count_bytes,
     wait_until,
 )
@@ -32,9 +32,9 @@ class WalletTest(BitcoinTestFramework):
         self.start_node(0)
         self.start_node(1)
         self.start_node(2)
-        connect_nodes_bi(self.nodes, 0, 1)
+        connect_nodes(self.nodes[0], 1)
-        connect_nodes_bi(self.nodes, 1, 2)
+        connect_nodes(self.nodes[1], 2)
-        connect_nodes_bi(self.nodes, 0, 2)
+        connect_nodes(self.nodes[0], 2)
         self.sync_all(self.nodes[0:3])
 
     def check_fee_amount(self, curr_balance, balance_with_fee, fee_per_byte, tx_size):
@@ -214,7 +214,7 @@ class WalletTest(BitcoinTestFramework):
         node_0_bal = self.check_fee_amount(self.nodes[0].getbalance(), node_0_bal + Decimal('100'), fee_per_byte, count_bytes(self.nodes[2].gettransaction(txid)['hex']))
 
         self.start_node(3)
-        connect_nodes_bi(self.nodes, 0, 3)
+        connect_nodes(self.nodes[0], 3)
         self.sync_all()
 
         # check if we can list zero value tx as available coins
@@ -249,9 +249,9 @@ class WalletTest(BitcoinTestFramework):
         self.start_node(0, ["-walletbroadcast=0"])
         self.start_node(1, ["-walletbroadcast=0"])
         self.start_node(2, ["-walletbroadcast=0"])
-        connect_nodes_bi(self.nodes, 0, 1)
+        connect_nodes(self.nodes[0], 1)
-        connect_nodes_bi(self.nodes, 1, 2)
+        connect_nodes(self.nodes[1], 2)
-        connect_nodes_bi(self.nodes, 0, 2)
+        connect_nodes(self.nodes[0], 2)
         self.sync_all(self.nodes[0:3])
 
         txid_not_broadcast = self.nodes[0].sendtoaddress(self.nodes[2].getnewaddress(), 2)
@@ -276,9 +276,9 @@ class WalletTest(BitcoinTestFramework):
         self.start_node(0)
         self.start_node(1)
         self.start_node(2)
-        connect_nodes_bi(self.nodes, 0, 1)
+        connect_nodes(self.nodes[0], 1)
-        connect_nodes_bi(self.nodes, 1, 2)
+        connect_nodes(self.nodes[1], 2)
-        connect_nodes_bi(self.nodes, 0, 2)
+        connect_nodes(self.nodes[0], 2)
         self.sync_blocks(self.nodes[0:3])
 
         self.nodes[0].generate(1)

test/functional/wallet_hd.py

@@ -10,7 +10,7 @@ import os
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import (
     assert_equal,
-    connect_nodes_bi,
+    connect_nodes,
 )
 
 class WalletHDTest(BitcoinTestFramework):
@@ -31,7 +31,7 @@ class WalletHDTest(BitcoinTestFramework):
         self.stop_node(1)
         self.nodes[1].assert_start_raises_init_error(['-usehd=0'], "Error: Error loading : You can't disable HD on an already existing HD wallet")
         self.start_node(1)
-        connect_nodes_bi(self.nodes, 0, 1)
+        connect_nodes(self.nodes[0], 1)
 
         # Make sure we use hd, keep chainid
         chainid = self.nodes[1].getwalletinfo()['hdchainid']
@@ -92,7 +92,7 @@ class WalletHDTest(BitcoinTestFramework):
             assert_equal(hd_info_2["hdkeypath"], "m/44'/1'/0'/0/"+str(i))
             assert_equal(hd_info_2["hdchainid"], chainid)
         assert_equal(hd_add, hd_add_2)
-        connect_nodes_bi(self.nodes, 0, 1)
+        connect_nodes(self.nodes[0], 1)
         self.sync_all()
 
         # Needs rescan
@@ -108,7 +108,7 @@ class WalletHDTest(BitcoinTestFramework):
         shutil.rmtree(os.path.join(self.nodes[1].datadir, self.chain, "llmq"))
         shutil.copyfile(os.path.join(self.nodes[1].datadir, "hd.bak"), os.path.join(self.nodes[1].datadir, self.chain, "wallets", "wallet.dat"))
         self.start_node(1, extra_args=self.extra_args[1])
-        connect_nodes_bi(self.nodes, 0, 1)
+        connect_nodes(self.nodes[0], 1)
         self.sync_all()
         # Wallet automatically scans blocks older than key on startup
         assert_equal(self.nodes[1].getbalance(), NUM_HD_ADDS + 1)

test/functional/wallet_keypool_topup.py

@@ -16,7 +16,7 @@ import shutil
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import (
     assert_equal,
-    connect_nodes_bi,
+    connect_nodes,
 )
 
 
@@ -38,7 +38,7 @@ class KeypoolRestoreTest(BitcoinTestFramework):
         self.stop_node(1)
         shutil.copyfile(wallet_path, wallet_backup_path)
         self.start_node(1, self.extra_args[1])
-        connect_nodes_bi(self.nodes, 0, 1)
+        connect_nodes(self.nodes[0], 1)
 
         self.log.info("Generate keys for wallet")
         for _ in range(90):
@@ -57,7 +57,7 @@ class KeypoolRestoreTest(BitcoinTestFramework):
         self.stop_node(1)
         shutil.copyfile(wallet_backup_path, wallet_path)
         self.start_node(1, self.extra_args[1])
-        connect_nodes_bi(self.nodes, 0, 1)
+        connect_nodes(self.nodes[0], 1)
         self.sync_all()
 
         self.log.info("Verify keypool is restored and balance is correct")

test/functional/wallet_listsinceblock.py

@@ -5,7 +5,13 @@
 """Test the listsincelast RPC."""
 
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import assert_equal, assert_array_result, assert_raises_rpc_error
+from test_framework.util import (
+    assert_array_result,
+    assert_equal,
+    assert_raises_rpc_error,
+    connect_nodes,
+)
+
 
 class ListSinceBlockTest(BitcoinTestFramework):
     def set_test_params(self):
@@ -16,6 +22,9 @@ class ListSinceBlockTest (BitcoinTestFramework):
         self.skip_if_no_wallet()
 
     def run_test(self):
+        # All nodes are in IBD from genesis, so they'll need the miner (node2) to be an outbound connection, or have
+        # only one connection. (See fPreferredDownload in net_processing)
+        connect_nodes(self.nodes[1], 2)
         self.nodes[2].generate(101)
         self.sync_all()