diff --git a/rhodecode/tests/lib/middleware/test_simplesvn.py b/rhodecode/tests/lib/middleware/test_simplesvn.py
--- a/rhodecode/tests/lib/middleware/test_simplesvn.py
+++ b/rhodecode/tests/lib/middleware/test_simplesvn.py
@@ -100,9 +100,9 @@ class TestSimpleSvn(object):
 
 
 class TestSimpleSvnApp(object):
-    data = '<xml></xml>'
+    data = b'<xml></xml>'
     path = '/group/my-repo'
-    wsgi_input = io.StringIO(data)
+    wsgi_input = io.BytesIO(data)
     environment = {
         'HTTP_DAV': (
             'http://subversion.tigris.org/xmlns/dav/svn/depth,'
@@ -187,7 +187,7 @@ class TestSimpleSvnApp(object):
             request_mock.return_value = response_mock
             self.app(self.environment, start_response)
 
-        expected_url = '{}{}'.format(self.host.strip('/'), self.path)
+        expected_url = f'{self.host.strip("/")}{self.path}'
         expected_request_headers = {
             'Dav': self.environment['HTTP_DAV'],
             'User-Agent': self.environment['HTTP_USER_AGENT'],