X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/32eb510594a45b395d1a0c8dafda1a94c86c0a9f..609646134bcd8fc3a7fd500848220741ecc4a9d2:/services/nodemanager/tests/testutil.py

diff --git a/services/nodemanager/tests/testutil.py b/services/nodemanager/tests/testutil.py
index a17f0882e6..15337c4120 100644
--- a/services/nodemanager/tests/testutil.py
+++ b/services/nodemanager/tests/testutil.py
@@ -2,13 +2,15 @@
 
 from __future__ import absolute_import, print_function
 
+import contextlib
 import datetime
+import mock
+import pykka
+import sys
 import threading
 import time
 
 import libcloud.common.types as cloud_types
-import mock
-import pykka
 
 from . import pykka_timeout
 
@@ -55,6 +57,17 @@ def cloud_node_fqdn(node):
 def ip_address_mock(last_octet):
     return '10.20.30.{}'.format(last_octet)
 
+@contextlib.contextmanager
+def redirected_streams(stdout=None, stderr=None):
+    orig_stdout, sys.stdout = sys.stdout, stdout or sys.stdout
+    orig_stderr, sys.stderr = sys.stderr, stderr or sys.stderr
+    try:
+        yield
+    finally:
+        sys.stdout = orig_stdout
+        sys.stderr = orig_stderr
+
+
 class MockShutdownTimer(object):
     def _set_state(self, is_open, next_opening):
         self.window_open = lambda: is_open
@@ -119,6 +132,13 @@ class ActorTestMixin(object):
             if result is not unassigned:
                 return result
 
+    def busywait(self, f):
+        n = 0
+        while not f() and n < 10:
+            time.sleep(.1)
+            n += 1
+        self.assertTrue(f())
+
 
 class DriverTestMixin(object):
     def setUp(self):