auto find next available local port

tests/test_mining_cli.py

@@ -3,6 +3,7 @@
 from __future__ import annotations
 
 import json
+import socket
 import sys
 import types
 from pathlib import Path
@@ -387,6 +388,43 @@ def test_legacy_start_treats_repo_model_as_model_id(monkeypatch):
     assert captured["model_id"] == "Qwen/Qwen2.5-0.5B-Instruct"
 
 
+def test_legacy_start_without_port_uses_next_available_port(monkeypatch):
+    """Omitting --port skips an occupied default port before startup loads the model."""
+    from meshnet_node.cli import main
+
+    captured = {}
+
+    def fake_run_startup(*args, **kwargs):
+        captured.update(kwargs)
+        class _FakeNode:
+            chat_completion_count = 0
+            def stop(self): pass
+        return _FakeNode()
+
+    occupied = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    occupied.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+    occupied.bind(("127.0.0.1", 7000))
+    occupied.listen(1)
+    try:
+        monkeypatch.setattr(sys, "argv", [
+            "meshnet-node", "start",
+            "--tracker", "http://192.168.0.179:8081",
+            "--model", "Qwen/Qwen2.5-0.5B-Instruct",
+            "--host", "127.0.0.1",
+        ])
+
+        with patch("meshnet_node.startup.run_startup", side_effect=fake_run_startup):
+            with patch("time.sleep", side_effect=KeyboardInterrupt):
+                try:
+                    main()
+                except SystemExit as exc:
+                    assert exc.code == 0
+    finally:
+        occupied.close()
+
+    assert captured["port"] == 7001
+
+
 def test_default_cli_passes_advertise_host(monkeypatch):
     """The documented no-subcommand LAN flag reaches startup."""
     from meshnet_node.cli import main