test: Use connect_nodes when connecting nodes in the test_framework

test/functional/p2p_disconnect_ban.py

@@ -18,6 +18,10 @@ 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")
@@ -74,7 +78,9 @@ 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")
 

test/functional/p2p_tx_download.py

@@ -121,6 +121,7 @@ class TxDownloadTest(BitcoinTestFramework):
         #   peer, plus
         # * the first time it is re-requested from the outbound peer, plus
         # * 2 seconds to avoid races
+        assert self.nodes[1].getpeerinfo()[0]['inbound'] == False
         timeout = 2 + (MAX_GETDATA_RANDOM_DELAY + INBOUND_PEER_TX_DELAY) + (
             GETDATA_TX_INTERVAL + MAX_GETDATA_RANDOM_DELAY)
         self.log.info("Tx should be received at node 1 after {} seconds".format(timeout))

test/functional/rpc_net.py

@@ -54,6 +54,10 @@ class NetTest(BitcoinTestFramework):
         self.extra_args = [["-minrelaytxfee=0.00001000"],["-minrelaytxfee=0.00000500"]]
 
     def run_test(self):
+        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()
         self._test_getnetworkinfo()
@@ -105,7 +109,10 @@ class NetTest(BitcoinTestFramework):
         wait_until(lambda: self.nodes[0].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/test_framework/test_framework.py

@@ -281,8 +281,18 @@ 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):

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()