test_worker: fix asyncio event loop management

artiq/test/test_worker.py

@@ -62,44 +62,42 @@ async def _call_worker(worker, expid):
         await worker.close()
 
 
-def _run_experiment(class_name):
+class WorkerCase(unittest.TestCase):
+    def setUp(self):
+        self.loop = asyncio.new_event_loop()
+        asyncio.set_event_loop(self.loop)
+
+    def _run_experiment(self, class_name):
         expid = {
             "log_level": logging.WARNING,
             "file": sys.modules[__name__].__file__,
             "class_name": class_name,
             "arguments": dict()
         }
-    loop = asyncio.get_event_loop()
         worker = Worker({})
-    loop.run_until_complete(_call_worker(worker, expid))
+        self.loop.run_until_complete(_call_worker(worker, expid))
-
-
-class WorkerCase(unittest.TestCase):
-    def setUp(self):
-        self.loop = asyncio.new_event_loop()
-        asyncio.set_event_loop(self.loop)
 
     def test_simple_run(self):
-        _run_experiment("SimpleExperiment")
+        self._run_experiment("SimpleExperiment")
 
     def test_exception(self):
         with self.assertLogs() as logs:
             with self.assertRaises(WorkerInternalException):
-                _run_experiment("ExceptionTermination")
+                self._run_experiment("ExceptionTermination")
             self.assertGreater(len(logs.records), 0)
             self.assertIn("Terminating with exception (TypeError)",
                           logs.output[-1])
 
     def test_watchdog_no_timeout(self):
-        _run_experiment("WatchdogNoTimeout")
+        self._run_experiment("WatchdogNoTimeout")
 
     def test_watchdog_timeout(self):
         with self.assertRaises(WorkerWatchdogTimeout):
-            _run_experiment("WatchdogTimeout")
+            self._run_experiment("WatchdogTimeout")
 
     def test_watchdog_timeout_in_build(self):
         with self.assertRaises(WorkerWatchdogTimeout):
-            _run_experiment("WatchdogTimeoutInBuild")
+            self._run_experiment("WatchdogTimeoutInBuild")
 
     def tearDown(self):
         self.loop.close()