py3: use six.moves.range instead of xrange

six is the canonical compatibility library for supporting
Python 2 and 3 in a single codebase.

The xrange module  was removed in Python 3 and we should
use 'six.moves.range' instead of 'xrange' to make
code compatible with py 2 and 3 as well.

Partially-implements blueprint py3-compatibility

Change-Id: Id054857f320d9eda02bc0b82e5512c0595342290

doc/ext/manila_todo.py

@@ -2,6 +2,7 @@
 # This is a hack of the builtin todo extension, to make the todo_list
 # more user friendly
 
+from six import moves
 from sphinx.ext.todo import *
 import re
 
@@ -25,7 +26,7 @@ def process_todo_nodes(app, doctree, fromdocname):
     # remove the item that was added in the constructor, since I'm tired of
     # reading through docutils for the proper way to construct an empty list
     lists = []
-    for i in xrange(5):
+    for i in moves.range(5):
         lists.append(nodes.bullet_list("", nodes.Text('', '')))
         lists[i].remove(lists[i][0])
         lists[i]['classes'].append('todo_list')

manila/tests/api/v1/test_limits.py

@@ -23,6 +23,7 @@ from xml.dom import minidom
 from lxml import etree
 from oslo.serialization import jsonutils
 import six
+from six import moves
 import webob
 
 from manila.api.v1 import limits
@@ -407,7 +408,7 @@ class LimiterTest(BaseLimitTestSuite):
 
     def _check(self, num, verb, url, username=None):
         """Check and yield results from checks."""
-        for x in xrange(num):
+        for x in moves.range(num):
             yield self.limiter.check_for_delay(verb, url, username)[0]
 
     def _check_sum(self, num, verb, url, username=None):

manila/tests/scheduler/test_host_manager.py

@@ -20,6 +20,7 @@ import datetime
 import mock
 from oslo.config import cfg
 from oslo.utils import timeutils
+from six import moves
 
 from manila import db
 from manila import exception
@@ -48,7 +49,7 @@ class HostManagerTestCase(test.TestCase):
         super(HostManagerTestCase, self).setUp()
         self.host_manager = host_manager.HostManager()
         self.fake_hosts = [host_manager.HostState('fake_host%s' % x)
-                           for x in xrange(1, 5)]
+                           for x in moves.range(1, 5)]
 
     def test_choose_host_filters_not_found(self):
         self.flags(scheduler_default_filters='FakeFilterClass3')
@@ -148,7 +149,7 @@ class HostManagerTestCase(test.TestCase):
 
             self.assertEqual(4, len(host_state_map))
             # Check that service is up
-            for i in xrange(4):
+            for i in moves.range(4):
                 share_node = fakes.SHARE_SERVICES[i]
                 host = share_node['host']
                 self.assertEqual(share_node, host_state_map[host].service)