Functional test for i2p fails due to connection attempt on port !=0

[gitcoindev]

I am reporting this issue while working on #63

Detected by failing functional test: p2p_i2p_ports.py

The test assumes that an I2P SAM proxy is not listening and tries to connect via i2p on port 8333.

Expected result:

Connection is not attempted.

Actual behaviour:

 node0 2021-11-17T08:14:18.170452Z [httpworker.2] [rpc/request.cpp:174] [parse] ThreadRPCServer method=addnode user=__cookie__ 
 node0 2021-11-17T08:14:18.170512Z [httpworker.2] [net.cpp:399] [ConnectNode] trying connection zsxwyo6qcn3chqzwxnseusqgsnuw3maqnztkiypyfxtya4snkoka.b32.i2p:8333 lastseen=0.0hrs 
 node0 2021-11-17T08:14:18.170531Z [httpworker.2] [i2p.cpp:239] [Log] I2P: Creating SAM session with 127.0.0.1:60000 
 node0 2021-11-17T08:14:18.170602Z [httpworker.2] [netbase.cpp:534] [LogConnectFailure] connect() to 127.0.0.1:60000 failed after wait: Connection refused (111) 
 node0 2021-11-17T08:14:18.170647Z [httpworker.2] [i2p.cpp:239] [Log] I2P: Error connecting to zsxwyo6qcn3chqzwxnseusqgsnuw3maqnztkiypyfxtya4snkoka.b32.i2p:8333: Cannot connect to 127.0.0.1:60000 
 node0 2021-11-17T08:14:18.170664Z [httpworker.2] [i2p.cpp:239] [Log] I2P: Control socket error: not connected 
 test  2021-11-17T08:14:18.171000Z TestFramework (ERROR): Assertion failed 
                                   Traceback (most recent call last):
                                     File "bitgesell/test/functional/test_framework/test_framework.py", line 132, in main
                                       self.run_test()
                                     File "test/functional/p2p_i2p_ports.py", line 34, in run_test
                                       raise AssertionError("Assertion should have been raised")

How to reproduce:

Run functional test: python test/functional/p2p_i2p_ports.py

Root cause:

Not known, yet.

The same test passes on btc@master:

$ python test/functional/p2p_i2p_ports.py
2021-11-17T08:20:03.515000Z TestFramework (INFO): Initializing test directory /tmp/bitcoin_func_test_32q6d44w
2021-11-17T08:20:03.800000Z TestFramework (INFO): Ensure we don't try to connect if port!=0
2021-11-17T08:20:05.816000Z TestFramework (INFO): Ensure we try to connect if port=0 and get an error due to missing I2P proxy
2021-11-17T08:20:05.870000Z TestFramework (INFO): Stopping nodes
2021-11-17T08:20:05.972000Z TestFramework (INFO): Cleaning up /tmp/bitcoin_func_test_32q6d44w on exit
2021-11-17T08:20:05.973000Z TestFramework (INFO): Tests successful

[gitcoindev]

Does not fail on master after last updates.