fix: 允许 Agent 持续自主诊断

tests/test_diagnostic_agent.py

@@ -121,6 +121,53 @@ class DiagnosticAgentTest(unittest.TestCase):
         self.assertEqual(action["action"], "command")
         self.assertEqual(action["command"], "kubectl get pods -A")
 
+    def test_ai_mode_continues_beyond_six_commands_until_model_finishes(self):
+        command_count = 8
+        responses = iter([
+            *[
+                (
+                    '{"action":"command","command":"kubectl get pods -A '
+                    f'--field-selector metadata.name=pod-{index}","reason":"继续收集证据"}}'
+                )
+                for index in range(command_count)
+            ],
+            '{"action":"final","analysis":"已完成根因分析"}',
+        ])
+        executed = []
+
+        async def fake_completion(messages):
+            return next(responses)
+
+        async def fake_execute(command):
+            executed.append(command)
+            return {"command": command, "mode": "read", "returncode": 0, "stdout": "evidence", "stderr": ""}
+
+        async def run():
+            with patch("backend.ai_agent._complete_chat", fake_completion), patch("backend.ai_agent.execute_kubectl", fake_execute):
+                return await collect_events(run_diagnostic_agent("report", execution_mode="ai", max_steps=20))
+
+        events = asyncio.run(run())
+        self.assertEqual(len(executed), command_count + 1)
+        self.assertEqual(events[-1]["type"], "final")
+        self.assertEqual(events[-1]["content"], "已完成根因分析")
+        self.assertNotIn("最大轮次", events[-1]["content"])
+
+    def test_safety_limit_reports_agent_error_instead_of_sending_user_to_manual_diagnosis(self):
+        async def fake_completion(messages):
+            return '{"action":"command","command":"kubectl get pods -A","reason":"继续调查"}'
+
+        async def fake_execute(command):
+            return {"command": command, "mode": "read", "returncode": 0, "stdout": "same result", "stderr": ""}
+
+        async def run():
+            with patch("backend.ai_agent._complete_chat", fake_completion), patch("backend.ai_agent.execute_kubectl", fake_execute):
+                return await collect_events(run_diagnostic_agent("report", execution_mode="ai", max_steps=2))
+
+        events = asyncio.run(run())
+        self.assertEqual(events[-1]["type"], "error")
+        self.assertIn("安全上限", events[-1]["message"])
+        self.assertNotIn("人工排查", events[-1]["message"])
+
     def test_stops_when_model_returns_invalid_action(self):
         async def fake_completion(messages):
             return "not-json"