Refactor radar system

python_app/tests/test_locator_client.py

@@ -0,0 +1,36 @@
+"""The locator test client's framing survives fragmented timeout polls."""
+
+import socket
+import threading
+import unittest
+from unittest.mock import Mock
+
+from locator_test_client import encode_packet, read_packet, recv_exactly
+
+
+class LocatorClientTest(unittest.TestCase):
+    def test_partial_header_and_payload_survive_timeouts(self) -> None:
+        payload = {"vlc": 5.5}
+        packet = encode_packet(payload, 7)
+        sock = Mock()
+        sock.recv.side_effect = [packet[:3], socket.timeout(), packet[3:8],
+                                 packet[8:10], socket.timeout(), packet[10:]]
+        self.assertEqual(read_packet(sock), (7, payload))
+
+    def test_timeout_wait_can_be_stopped_without_losing_thread(self) -> None:
+        stop = threading.Event()
+        sock = Mock()
+
+        def receive(_size):
+            stop.set()
+            raise socket.timeout()
+
+        sock.recv.side_effect = receive
+        with self.assertRaisesRegex(ConnectionError, "stopped"):
+            recv_exactly(sock, 8, stop)
+
+    def test_eof_in_the_middle_of_packet_is_reported(self) -> None:
+        sock = Mock()
+        sock.recv.side_effect = [b"123", b""]
+        with self.assertRaisesRegex(ConnectionError, "closed"):
+            read_packet(sock)