test: ensure I2P ports are handled as expected

test/functional/p2p_i2p_ports.py

@@ -0,0 +1,43 @@
+#!/usr/bin/env python3
+# Copyright (c) 2021-2021 The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+"""
+Test ports handling for I2P hosts
+"""
+
+import re
+
+from test_framework.test_framework import BitcoinTestFramework
+
+
+class I2PPorts(BitcoinTestFramework):
+    def set_test_params(self):
+        self.num_nodes = 1
+        # The test assumes that an I2P SAM proxy is not listening here.
+        self.extra_args = [["-i2psam=127.0.0.1:60000"]]
+
+    def run_test(self):
+        node = self.nodes[0]
+
+        self.log.info("Ensure we don't try to connect if port!=0")
+        addr = "zsxwyo6qcn3chqzwxnseusqgsnuw3maqnztkiypyfxtya4snkoka.b32.i2p:8333"
+        raised = False
+        try:
+            with node.assert_debug_log(expected_msgs=[f"Error connecting to {addr}"]):
+                node.addnode(node=addr, command="onetry")
+        except AssertionError as e:
+            raised = True
+            if not re.search(r"Expected messages .* does not partially match log", str(e)):
+                raise AssertionError(f"Assertion raised as expected, but with an unexpected message: {str(e)}")
+        if not raised:
+            raise AssertionError("Assertion should have been raised")
+
+        self.log.info("Ensure we try to connect if port=0 and get an error due to missing I2P proxy")
+        addr = "h3r6bkn46qxftwja53pxiykntegfyfjqtnzbm6iv6r5mungmqgmq.b32.i2p:0"
+        with node.assert_debug_log(expected_msgs=[f"Error connecting to {addr}"]):
+            node.addnode(node=addr, command="onetry")
+
+
+if __name__ == '__main__':
+    I2PPorts().main()

test/functional/test_runner.py

@@ -291,6 +291,7 @@ BASE_SCRIPTS = [
     'p2p_permissions.py',
     'feature_blocksdir.py',
     'wallet_startup.py',
+    'p2p_i2p_ports.py',
     'feature_config_args.py',
     'feature_settings.py',
     'rpc_getdescriptorinfo.py',