1 files changed, 38 insertions, 3 deletions
diff --git a/app/tests/test_backends_servers.py b/app/tests/test_backends_servers.py
index ab05eed..61897d4 100644
--- a/app/tests/test_backends_servers.py
+++ b/app/tests/test_backends_servers.py
@@ -65,10 +65,45 @@ class StartTests(unittest.TestCase):
             ok = servers.start(self.spec)
         self.assertTrue(ok)
         mk.assert_called_once()
-        # Pid file written.
+        # Pid file written (first field is the pid; the optional second
+        # field is the start-time ownership token, absent on this platform).
         self.assertEqual(
-            (self.dir / "test-server.pid").read_text(encoding="utf-8"),
-            "4242")
+            (self.dir / "test-server.pid").read_text(encoding="utf-8")
+            .split()[0], "4242")
+
+    def test_pid_file_records_a_start_time_token_where_available(self):
+        proc = MagicMock()
+        proc.pid = 5150
+        proc.poll.return_value = None
+        with patch.object(servers, "LOG_DIR", self.dir), \
+                patch("subprocess.Popen", return_value=proc), \
+                patch.object(servers, "_process_start_token",
+                             return_value="12345"), \
+                patch("backends.common.server_running",
+                      side_effect=[False, True]), \
+                patch("time.sleep"):
+            self.assertTrue(servers.start(self.spec))
+        fields = (self.dir / "test-server.pid") \
+            .read_text(encoding="utf-8").split()
+        self.assertEqual(fields, ["5150", "12345"])
+
+    def test_recycled_pid_with_mismatched_token_is_not_ours(self):
+        # The pid is alive but its start time differs from the recorded
+        # token: an unrelated process now owns this pid, so manages/alive
+        # must report not-ours (and never kill it).
+        pid_file = self.dir / "test-server.pid"
+        pid_file.write_text("4242 111\n", encoding="utf-8")
+        with patch.object(servers, "LOG_DIR", self.dir), \
+                patch.object(servers, "_pid_alive", return_value=True), \
+                patch.object(servers, "_process_start_token",
+                             return_value="999"):
+            self.assertFalse(servers.alive("test"))
+            self.assertFalse(servers.manages([self.spec]))
+        with patch.object(servers, "LOG_DIR", self.dir), \
+                patch.object(servers, "_pid_alive", return_value=True), \
+                patch.object(servers, "_process_start_token",
+                             return_value="111"):
+            self.assertTrue(servers.alive("test"))
 
     def test_returns_false_when_process_exits_early(self):
         proc = MagicMock()