"""Regression for tests/_port_alloc.free_test_port."""
import os
import socket
import sys
import unittest

sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
from _port_alloc import free_test_port  # noqa: E402


class FreeTestPortTests(unittest.TestCase):
    def test_two_calls_return_distinct_bindable_ports(self):
        first = free_test_port()
        second = free_test_port()
        self.assertNotEqual(first, second)
        for port in (first, second):
            with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as listener:
                listener.bind(("127.0.0.1", port))
                listener.listen(1)
                self.assertEqual(listener.getsockname()[1], port)


if __name__ == "__main__":
    unittest.main()