Avoid py36 error when printing unicode chars in a stream

The IOStream was not able to encode characters out of range 128:
  "UnicodeEncodeError: 'ascii' codec can't encode characters in
   position 19-21: ordinal not in range(128)"

Change-Id: Ic95396a5cf73c49d332928857dc064819a6d7ea6
Closes-Bug: #1858421

1 files changed, 7 insertions, 6 deletions

diff --git a/neutronclient/tests/unit/test_exceptions.py b/neutronclient/tests/unit/test_exceptions.py
index 9174287..aefc24c 100644
--- a/neutronclient/tests/unit/test_exceptions.py
+++ b/neutronclient/tests/unit/test_exceptions.py
@@ -12,7 +12,9 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import fixtures
+import sys
+
+import mock
 from oslo_utils import encodeutils
 import six
 import testtools
@@ -30,12 +32,11 @@ class TestExceptions(testtools.TestCase):
         multibyte_unicode_string = u'\uff21\uff22\uff23'
         e = TestException(reason=multibyte_unicode_string)
 
-        fixture = fixtures.StringStream('stdout')
-        self.useFixture(fixture)
-        with fixtures.MonkeyPatch('sys.stdout', fixture.stream):
+        with mock.patch.object(sys, 'stdout') as mock_stdout:
             print(e)
-        self.assertEqual('Exception with %s' % multibyte_unicode_string,
-                         fixture.getDetails().get('stdout').as_text())
+
+        exc_str = 'Exception with %s' % multibyte_unicode_string
+        mock_stdout.assert_has_calls([mock.call.write(exc_str)])
 
     def test_exception_message_with_encoded_unicode(self):
         class TestException(exceptions.NeutronException):