Fix race in tests

Author: DomAyre

src/confcom/azext_confcom/tests/latest/test_confcom_arm.py

@@ -3,10 +3,13 @@
 # Licensed under the MIT License. See License.txt in the project root for license information.
 # --------------------------------------------------------------------------------------------
 
+import fcntl
 import os
 import unittest
 import json
 import deepdiff
+import docker
+import requests
 from unittest.mock import patch
 
 from azext_confcom.security_policy import (
@@ -24,6 +27,7 @@
 )
 
 TEST_DIR = os.path.abspath(os.path.join(os.path.abspath(__file__), ".."))
+PRUNE_LOCK_PATH = "/tmp/confcom_docker_prune.lock"
 
 
 class PolicyGeneratingArm(unittest.TestCase):
@@ -5007,7 +5011,18 @@ def setUpClass(cls):
 
     @classmethod
     def tearDownClass(cls):
-        cls.client.containers.prune()
+        # Coordinate cleanup across xdist workers to avoid prune conflicts.
+        with open(PRUNE_LOCK_PATH, "w") as lock_file:
+            fcntl.flock(lock_file, fcntl.LOCK_EX)
+            try:
+                cls.client.containers.prune()
+            except (docker.errors.APIError, requests.exceptions.ReadTimeout) as exc:
+                # Ignore conflicts (another prune in flight) or slow daemon timeouts.
+                status = getattr(getattr(exc, "response", None), "status_code", None)
+                if status not in (409, None) or not isinstance(exc, requests.exceptions.ReadTimeout):
+                    raise
+            finally:
+                fcntl.flock(lock_file, fcntl.LOCK_UN)
         cls.client.close()
 
     def test_arm_template_security_context_no_run_as_group(self):