Merge "Remove six"

13 files changed, 67 insertions, 90 deletions

diff --git a/oslo_config/cfg.py b/oslo_config/cfg.py
index 06d50bb..638e4ff 100644
--- a/oslo_config/cfg.py
+++ b/oslo_config/cfg.py
@@ -17,15 +17,9 @@
 
 import argparse
 import collections
-
-# TODO(smcginnis) update this once six has support for collections.abc
-# (https://github.com/benjaminp/six/pull/241) or clean up once we drop py2.7.
-try:
-    from collections.abc import Mapping
-except ImportError:
-    from collections import Mapping
-
+from collections import abc
 import copy
+import enum
 import errno
 import functools
 import glob
@@ -36,8 +30,6 @@ import os
 import string
 import sys
 
-import enum
-import six
 # NOTE(bnemec): oslo.log depends on oslo.config, so we can't
 # have a hard dependency on oslo.log.  However, in most cases
 # oslo.log will be installed so we can use it.
@@ -607,7 +599,7 @@ class Opt(object):
 
     def _default_is_ref(self):
         """Check if default is a reference to another var."""
-        if isinstance(self.default, six.string_types):
+        if isinstance(self.default, str):
             tmpl = self.default.replace(r'\$', '').replace('$$', '')
             return '$' in tmpl
         return False
@@ -939,7 +931,7 @@ class StrOpt(Opt):
             return '<None>'
         elif choice == '':
             return "''"
-        return six.text_type(choice)
+        return str(choice)
 
     def _get_argparse_kwargs(self, group, **kwargs):
         """Extends the base argparse keyword dict for the config dir option."""
@@ -1564,7 +1556,7 @@ class ConfigParser(iniparser.BaseParser):
 
     def parse(self):
         with open(self.filename) as f:
-            return super(ConfigParser, self).parse(f)
+            return super(ConfigParser, self).parse(f.readlines())
 
     def new_section(self, section):
         self.section = section
@@ -1930,7 +1922,7 @@ class _CachedArgumentParser(argparse.ArgumentParser):
         super(_CachedArgumentParser, self).print_usage(file)
 
 
-class ConfigOpts(Mapping):
+class ConfigOpts(abc.Mapping):
 
     """Config options which may be set on the command line or in config files.
 
@@ -3121,7 +3113,7 @@ class ConfigOpts(Mapping):
         value, loc = self._do_get(name, opt_group, None)
         return loc
 
-    class GroupAttr(Mapping):
+    class GroupAttr(abc.Mapping):
 
         """Helper class.
 
diff --git a/oslo_config/generator.py b/oslo_config/generator.py
index ba75c4c..1f509ef 100644
--- a/oslo_config/generator.py
+++ b/oslo_config/generator.py
@@ -32,7 +32,6 @@ import textwrap
 
 import json
 import pkg_resources
-import six
 import yaml
 
 
@@ -119,7 +118,7 @@ def _format_defaults(opt):
             default_str = str(opt.default)
         elif isinstance(opt, (cfg.ListOpt, cfg._ConfigFileOpt,
                               cfg._ConfigDirOpt)):
-            default_str = ','.join(six.text_type(d) for d in opt.default)
+            default_str = ','.join(str(d) for d in opt.default)
         elif isinstance(opt, cfg.DictOpt):
             sorted_items = sorted(opt.default.items(),
                                   key=operator.itemgetter(0))
@@ -131,8 +130,8 @@ def _format_defaults(opt):
 
     results = []
     for default_str in defaults:
-        if not isinstance(default_str, six.text_type):
-            default_str = six.text_type(default_str)
+        if not isinstance(default_str, str):
+            default_str = str(default_str)
         if default_str.strip() != default_str:
             default_str = '"%s"' % default_str
         results.append(default_str)
@@ -201,7 +200,7 @@ class _OptFormatter(object):
             return '<None>'
         elif choice == '':
             return "''"
-        return six.text_type(choice)
+        return str(choice)
 
     def format_group(self, group_or_groupname):
         """Format the description of a group header to the output file
diff --git a/oslo_config/sources/__init__.py b/oslo_config/sources/__init__.py
index a37c6c4..e3e99af 100644
--- a/oslo_config/sources/__init__.py
+++ b/oslo_config/sources/__init__.py
@@ -42,7 +42,6 @@ The Configuration Source Class
 """
 
 import abc
-import six
 
 
 # We cannot use None as a sentinel indicating a missing value because it
@@ -50,8 +49,7 @@ import six
 _NoValue = object()
 
 
-@six.add_metaclass(abc.ABCMeta)
-class ConfigurationSourceDriver(object):
+class ConfigurationSourceDriver(object, metaclass=abc.ABCMeta):
     """A backend driver option for oslo.config.
 
     For each group name listed in **config_source** on the **DEFAULT** group,
@@ -114,8 +112,7 @@ class ConfigurationSourceDriver(object):
         """
 
 
-@six.add_metaclass(abc.ABCMeta)
-class ConfigurationSource(object):
+class ConfigurationSource(object, metaclass=abc.ABCMeta):
     """A configuration source option for oslo.config.
 
     A configuration source is able to fetch configuration values based on
diff --git a/oslo_config/sphinxext.py b/oslo_config/sphinxext.py
index 0f32c20..905490c 100644
--- a/oslo_config/sphinxext.py
+++ b/oslo_config/sphinxext.py
@@ -15,7 +15,6 @@ from docutils.parsers import rst
 from docutils.parsers.rst import directives
 from docutils.statemachine import ViewList
 import oslo_i18n
-import six
 from sphinx import addnodes
 from sphinx.directives import ObjectDescription
 from sphinx.domains import Domain
@@ -89,7 +88,7 @@ def _get_choice_text(choice):
         return '<None>'
     elif choice == '':
         return "''"
-    return six.text_type(choice)
+    return str(choice)
 
 
 def _format_opt(opt, group_name):
diff --git a/oslo_config/tests/test_cfg.py b/oslo_config/tests/test_cfg.py
index e304807..302f39f 100644
--- a/oslo_config/tests/test_cfg.py
+++ b/oslo_config/tests/test_cfg.py
@@ -15,6 +15,7 @@
 import argparse
 import errno
 import functools
+import io
 import logging
 import os
 import shutil
@@ -24,8 +25,6 @@ import tempfile
 import fixtures
 import mock
 from oslotest import base
-import six
-from six import moves
 import testscenarios
 
 from oslo_config import cfg
@@ -139,7 +138,7 @@ class BaseTestCase(base.BaseTestCase):
 class UsageTestCase(BaseTestCase):
 
     def test_print_usage(self):
-        f = moves.StringIO()
+        f = io.StringIO()
         self.conf([])
         self.conf.print_usage(file=f)
         self.assertIn(
@@ -154,7 +153,7 @@ class UsageTestCase(BaseTestCase):
         conf = self.TestConfigOpts()
 
         self.tempdirs = []
-        f = moves.StringIO()
+        f = io.StringIO()
         conf([], usage='%(prog)s FOO BAR')
         conf.print_usage(file=f)
         self.assertIn('usage: test FOO BAR', f.getvalue())
@@ -163,7 +162,7 @@ class UsageTestCase(BaseTestCase):
         self.assertNotIn('optional:', f.getvalue())
 
     def test_print_help(self):
-        f = moves.StringIO()
+        f = io.StringIO()
         self.conf([])
         self.conf.print_help(file=f)
         self.assertIn(
@@ -178,7 +177,7 @@ class UsageTestCase(BaseTestCase):
 class HelpTestCase(BaseTestCase):
 
     def test_print_help(self):
-        f = moves.StringIO()
+        f = io.StringIO()
         self.conf([])
         self.conf.print_help(file=f)
         self.assertIn(
@@ -189,7 +188,7 @@ class HelpTestCase(BaseTestCase):
         self.assertIn('-h, --help', f.getvalue())
 
     def test_print_strOpt_with_choices_help(self):
-        f = moves.StringIO()
+        f = io.StringIO()
         cli_opts = [
             cfg.StrOpt('aa', short='a', default='xx',
                        choices=['xx', 'yy', 'zz'],
@@ -218,7 +217,7 @@ class HelpTestCase(BaseTestCase):
                       f.getvalue())
 
     def test_print_sorted_help(self):
-        f = moves.StringIO()
+        f = io.StringIO()
         self.conf.register_cli_opt(cfg.StrOpt('abc'))
         self.conf.register_cli_opt(cfg.StrOpt('zba'))
         self.conf.register_cli_opt(cfg.StrOpt('ghi'))
@@ -233,7 +232,7 @@ class HelpTestCase(BaseTestCase):
         self.assertEqual(sorted(list), list)
 
     def test_print_sorted_help_with_positionals(self):
-        f = moves.StringIO()
+        f = io.StringIO()
         self.conf.register_cli_opt(
             cfg.StrOpt('pst', positional=True, required=False))
         self.conf.register_cli_opt(cfg.StrOpt('abc'))
@@ -248,7 +247,7 @@ class HelpTestCase(BaseTestCase):
         self.assertEqual(sorted(list), list)
 
     def test_print_help_with_deprecated(self):
-        f = moves.StringIO()
+        f = io.StringIO()
         abc = cfg.StrOpt('a-bc',
                          deprecated_opts=[cfg.DeprecatedOpt('d-ef')])
         uvw = cfg.StrOpt('u-vw',
@@ -779,7 +778,7 @@ class CliOptsTestCase(BaseTestCase):
 class CliSpecialOptsTestCase(BaseTestCase):
 
     def test_help(self):
-        self.useFixture(fixtures.MonkeyPatch('sys.stdout', moves.StringIO()))
+        self.useFixture(fixtures.MonkeyPatch('sys.stdout', io.StringIO()))
         self.assertRaises(SystemExit, self.conf, ['--help'])
         self.assertIn('usage: test', sys.stdout.getvalue())
         self.assertIn('[--version]', sys.stdout.getvalue())
@@ -796,7 +795,7 @@ class CliSpecialOptsTestCase(BaseTestCase):
         else:
             stream_name = 'stderr'
         self.useFixture(fixtures.MonkeyPatch("sys.%s" % stream_name,
-                                             moves.StringIO()))
+                                             io.StringIO()))
         self.assertRaises(SystemExit, self.conf, ['--version'])
         self.assertIn('1.0', getattr(sys, stream_name).getvalue())
 
@@ -925,7 +924,7 @@ class PositionalTestCase(BaseTestCase):
         self.conf.register_cli_opt(
             cfg.StrOpt('foo', required=True, positional=True))
 
-        self.useFixture(fixtures.MonkeyPatch('sys.stdout', moves.StringIO()))
+        self.useFixture(fixtures.MonkeyPatch('sys.stdout', io.StringIO()))
         self.assertRaises(SystemExit, self.conf, ['--help'])
         self.assertIn(' foo\n', sys.stdout.getvalue())
 
@@ -938,7 +937,7 @@ class PositionalTestCase(BaseTestCase):
         self.conf.register_cli_opt(
             cfg.StrOpt('foo', required=True, positional=True))
 
-        self.useFixture(fixtures.MonkeyPatch('sys.stdout', moves.StringIO()))
+        self.useFixture(fixtures.MonkeyPatch('sys.stdout', io.StringIO()))
         self.assertRaises(SystemExit, self.conf, ['--help'])
         self.assertIn(' foo\n', sys.stdout.getvalue())
 
@@ -948,7 +947,7 @@ class PositionalTestCase(BaseTestCase):
         self.conf.register_cli_opt(
             cfg.StrOpt('foo', required=False, positional=True))
 
-        self.useFixture(fixtures.MonkeyPatch('sys.stdout', moves.StringIO()))
+        self.useFixture(fixtures.MonkeyPatch('sys.stdout', io.StringIO()))
         self.assertRaises(SystemExit, self.conf, ['--help'])
         self.assertIn(' [foo]\n', sys.stdout.getvalue())
 
@@ -961,7 +960,7 @@ class PositionalTestCase(BaseTestCase):
         self.conf.register_cli_opt(
             cfg.StrOpt('foo', required=False, positional=True))
 
-        self.useFixture(fixtures.MonkeyPatch('sys.stdout', moves.StringIO()))
+        self.useFixture(fixtures.MonkeyPatch('sys.stdout', io.StringIO()))
         self.assertRaises(SystemExit, self.conf, ['--help'])
         self.assertIn(' [foo]\n', sys.stdout.getvalue())
 
@@ -974,7 +973,7 @@ class PositionalTestCase(BaseTestCase):
         self.conf.register_cli_opt(
             cfg.StrOpt('foo-bar', required=False, positional=True))
 
-        self.useFixture(fixtures.MonkeyPatch('sys.stdout', moves.StringIO()))
+        self.useFixture(fixtures.MonkeyPatch('sys.stdout', io.StringIO()))
         self.assertRaises(SystemExit, self.conf, ['--help'])
         self.assertIn(' [foo_bar]\n', sys.stdout.getvalue())
 
@@ -986,7 +985,7 @@ class PositionalTestCase(BaseTestCase):
         self.conf.register_cli_opt(
             cfg.StrOpt('foo-bar', required=False, positional=True))
 
-        self.useFixture(fixtures.MonkeyPatch('sys.stdout', moves.StringIO()))
+        self.useFixture(fixtures.MonkeyPatch('sys.stdout', io.StringIO()))
         self.assertRaises(SystemExit, self.conf, ['--help'])
         self.assertIn(' [foo_bar]\n', sys.stdout.getvalue())
 
@@ -998,7 +997,7 @@ class PositionalTestCase(BaseTestCase):
         self.conf.register_cli_opt(
             cfg.StrOpt('foo-bar', required=True, positional=True))
 
-        self.useFixture(fixtures.MonkeyPatch('sys.stdout', moves.StringIO()))
+        self.useFixture(fixtures.MonkeyPatch('sys.stdout', io.StringIO()))
         self.assertRaises(SystemExit, self.conf, ['--help'])
         self.assertIn(' foo_bar\n', sys.stdout.getvalue())
 
@@ -1010,7 +1009,7 @@ class PositionalTestCase(BaseTestCase):
         self.conf.register_cli_opt(
             cfg.StrOpt('foo-bar', required=True, positional=True))
 
-        self.useFixture(fixtures.MonkeyPatch('sys.stdout', moves.StringIO()))
+        self.useFixture(fixtures.MonkeyPatch('sys.stdout', io.StringIO()))
         self.assertRaises(SystemExit, self.conf, ['--help'])
         self.assertIn(' foo_bar\n', sys.stdout.getvalue())
 
@@ -3775,7 +3774,7 @@ class SadPathTestCase(BaseTestCase):
     def test_bad_cli_arg(self):
         self.conf.register_opt(cfg.BoolOpt('foo'))
 
-        self.useFixture(fixtures.MonkeyPatch('sys.stderr', moves.StringIO()))
+        self.useFixture(fixtures.MonkeyPatch('sys.stderr', io.StringIO()))
 
         self.assertRaises(SystemExit, self.conf, ['--foo'])
 
@@ -3785,7 +3784,7 @@ class SadPathTestCase(BaseTestCase):
     def _do_test_bad_cli_value(self, opt_class):
         self.conf.register_cli_opt(opt_class('foo'))
 
-        self.useFixture(fixtures.MonkeyPatch('sys.stderr', moves.StringIO()))
+        self.useFixture(fixtures.MonkeyPatch('sys.stderr', io.StringIO()))
 
         self.assertRaises(SystemExit, self.conf, ['--foo', 'bar'])
 
@@ -4071,7 +4070,7 @@ class ConfigParserTestCase(BaseTestCase):
 
     def test_no_section(self):
         with tempfile.NamedTemporaryFile() as tmpfile:
-            tmpfile.write(six.b('foo = bar'))
+            tmpfile.write(b'foo = bar')
             tmpfile.flush()
 
             parser = cfg.ConfigParser(tmpfile.name, {})
@@ -4306,7 +4305,7 @@ class SubCommandTestCase(BaseTestCase):
 
     def test_sub_command_no_handler(self):
         self.conf.register_cli_opt(cfg.SubCommandOpt('cmd'))
-        self.useFixture(fixtures.MonkeyPatch('sys.stderr', moves.StringIO()))
+        self.useFixture(fixtures.MonkeyPatch('sys.stderr', io.StringIO()))
         self.assertRaises(SystemExit, self.conf, [])
         self.assertIn('error', sys.stderr.getvalue())
 
@@ -4319,7 +4318,7 @@ class SubCommandTestCase(BaseTestCase):
                                                      description='bar bar',
                                                      help='blaa blaa',
                                                      handler=add_parsers))
-        self.useFixture(fixtures.MonkeyPatch('sys.stdout', moves.StringIO()))
+        self.useFixture(fixtures.MonkeyPatch('sys.stdout', io.StringIO()))
         self.assertRaises(SystemExit, self.conf, ['--help'])
         self.assertIn('foo foo', sys.stdout.getvalue())
         self.assertIn('bar bar', sys.stdout.getvalue())
@@ -4340,7 +4339,7 @@ class SubCommandTestCase(BaseTestCase):
     def test_sub_command_multiple(self):
         self.conf.register_cli_opt(cfg.SubCommandOpt('cmd1'))
         self.conf.register_cli_opt(cfg.SubCommandOpt('cmd2'))
-        self.useFixture(fixtures.MonkeyPatch('sys.stderr', moves.StringIO()))
+        self.useFixture(fixtures.MonkeyPatch('sys.stderr', io.StringIO()))
         self.assertRaises(SystemExit, self.conf, [])
         self.assertIn('multiple', sys.stderr.getvalue())
 
diff --git a/oslo_config/tests/test_generator.py b/oslo_config/tests/test_generator.py
index f28e5ea..becd49a 100644
--- a/oslo_config/tests/test_generator.py
+++ b/oslo_config/tests/test_generator.py
@@ -12,13 +12,13 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import io
 import sys
 import textwrap
 
 import fixtures
 import mock
 from oslotest import base
-from six import moves
 import tempfile
 import testscenarios
 
@@ -963,7 +963,7 @@ class GeneratorTestCase(base.BaseTestCase):
 
     def _capture_stream(self, stream_name):
         self.useFixture(fixtures.MonkeyPatch("sys.%s" % stream_name,
-                                             moves.StringIO()))
+                                             io.StringIO()))
         return getattr(sys, stream_name)
 
     def _capture_stdout(self):
@@ -1103,7 +1103,7 @@ class DriverOptionTestCase(base.BaseTestCase):
         # Initialize the generator to produce YAML output to a buffer.
         generator.register_cli_opts(self.conf)
         self.config(namespace=['test_generator'], format_='yaml')
-        stdout = moves.StringIO()
+        stdout = io.StringIO()
 
         # Generate the output and parse it back to a data structure.
         generator.generate(self.conf, output_file=stdout)
@@ -1609,7 +1609,7 @@ class GeneratorAdditionalTestCase(base.BaseTestCase):
 class GeneratorMutableOptionTestCase(base.BaseTestCase):
 
     def test_include_message(self):
-        out = moves.StringIO()
+        out = io.StringIO()
         opt = cfg.StrOpt('foo', help='foo option', mutable=True)
         gen = build_formatter(out)
         gen.format(opt, 'group1')
@@ -1620,7 +1620,7 @@ class GeneratorMutableOptionTestCase(base.BaseTestCase):
         )
 
     def test_do_not_include_message(self):
-        out = moves.StringIO()
+        out = io.StringIO()
         opt = cfg.StrOpt('foo', help='foo option', mutable=False)
         gen = build_formatter(out)
         gen.format(opt, 'group1')
@@ -1854,7 +1854,7 @@ class HostAddressTestCase(base.BaseTestCase):
         config = [("namespace", [("alpha", self.opts)])]
         groups = generator._get_groups(config)
 
-        out = moves.StringIO()
+        out = io.StringIO()
         formatter = build_formatter(out)
         generator._output_opts(formatter, 'alpha', groups.pop('alpha'))
         result = out.getvalue()
@@ -1871,5 +1871,6 @@ class HostAddressTestCase(base.BaseTestCase):
         ''').lstrip()
         self.assertEqual(expected, result)
 
+
 GeneratorTestCase.generate_scenarios()
 MachineReadableGeneratorTestCase.generate_scenarios()
diff --git a/oslo_config/tests/test_sources.py b/oslo_config/tests/test_sources.py
index dca83b8..656f61e 100644
--- a/oslo_config/tests/test_sources.py
+++ b/oslo_config/tests/test_sources.py
@@ -12,7 +12,9 @@
 
 import os
 
+from oslotest import base
 from requests import HTTPError
+import requests_mock
 
 from oslo_config import _list_opts
 from oslo_config import cfg
@@ -20,9 +22,6 @@ from oslo_config import fixture
 from oslo_config import sources
 from oslo_config.sources import _uri
 
-from oslotest import base
-import requests_mock
-
 
 class TestProcessingSources(base.BaseTestCase):
 
diff --git a/oslo_config/tests/test_sphinxconfiggen.py b/oslo_config/tests/test_sphinxconfiggen.py
index f28c731..982641e 100644
--- a/oslo_config/tests/test_sphinxconfiggen.py
+++ b/oslo_config/tests/test_sphinxconfiggen.py
@@ -10,7 +10,6 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-
 import mock
 from oslotest import base
 
diff --git a/oslo_config/tests/test_types.py b/oslo_config/tests/test_types.py
index e4f4779..644a239 100644
--- a/oslo_config/tests/test_types.py
+++ b/oslo_config/tests/test_types.py
@@ -16,7 +16,6 @@ import re
 import unittest
 
 from oslo_config import types
-from six.moves import range as compat_range
 
 
 class ConfigTypeTests(unittest.TestCase):
@@ -601,7 +600,7 @@ class RangeTypeTests(TypeTestHelper, unittest.TestCase):
     type = types.Range()
 
     def assertRange(self, s, r1, r2, step=1):
-        self.assertEqual(list(compat_range(r1, r2, step)),
+        self.assertEqual(list(range(r1, r2, step)),
                          list(self.type_instance(s)))
 
     def test_range(self):
diff --git a/oslo_config/tests/test_validator.py b/oslo_config/tests/test_validator.py
index 9d4aef8..a2ffde7 100644
--- a/oslo_config/tests/test_validator.py
+++ b/oslo_config/tests/test_validator.py
@@ -14,7 +14,6 @@
 
 import mock
 from oslotest import base
-import six
 
 from oslo_config import cfg
 from oslo_config import fixture
@@ -49,10 +48,6 @@ class TestValidator(base.BaseTestCase):
         self.conf = cfg.ConfigOpts()
         self.conf_fixture = self.useFixture(fixture.Config(self.conf))
         validator._register_cli_opts(self.conf)
-        if six.PY2:
-            self.open_name = '__builtin__.open'
-        else:
-            self.open_name = 'builtins.open'
 
     @mock.patch('oslo_config.validator.load_opt_data')
     def test_passing(self, mock_lod):
@@ -60,7 +55,7 @@ class TestValidator(base.BaseTestCase):
         self.conf_fixture.config(opt_data='mocked.yaml',
                                  input_file='mocked.conf')
         m = mock.mock_open(read_data=VALID_CONF)
-        with mock.patch(self.open_name, m):
+        with mock.patch('builtins.open', m):
             self.assertEqual(0, validator._validate(self.conf))
 
     @mock.patch('oslo_config.validator.load_opt_data')
@@ -69,7 +64,7 @@ class TestValidator(base.BaseTestCase):
         self.conf_fixture.config(opt_data='mocked.yaml',
                                  input_file='mocked.conf')
         m = mock.mock_open(read_data=DEPRECATED_CONF)
-        with mock.patch(self.open_name, m):
+        with mock.patch('builtins.open', m):
             self.assertEqual(0, validator._validate(self.conf))
 
     @mock.patch('oslo_config.validator.load_opt_data')
@@ -79,7 +74,7 @@ class TestValidator(base.BaseTestCase):
                                  input_file='mocked.conf',
                                  fatal_warnings=True)
         m = mock.mock_open(read_data=DEPRECATED_CONF)
-        with mock.patch(self.open_name, m):
+        with mock.patch('builtins.open', m):
             self.assertEqual(1, validator._validate(self.conf))
 
     @mock.patch('oslo_config.validator.load_opt_data')
@@ -88,7 +83,7 @@ class TestValidator(base.BaseTestCase):
         self.conf_fixture.config(opt_data='mocked.yaml',
                                  input_file='mocked.conf')
         m = mock.mock_open(read_data=INVALID_CONF)
-        with mock.patch(self.open_name, m):
+        with mock.patch('builtins.open', m):
             self.assertEqual(1, validator._validate(self.conf))
 
     @mock.patch('oslo_config.validator.load_opt_data')
@@ -97,7 +92,7 @@ class TestValidator(base.BaseTestCase):
         self.conf_fixture.config(opt_data='mocked.yaml',
                                  input_file='mocked.conf')
         m = mock.mock_open(read_data=MISSING_GROUP_CONF)
-        with mock.patch(self.open_name, m):
+        with mock.patch('builtins.open', m):
             self.assertEqual(1, validator._validate(self.conf))
 
     @mock.patch('oslo_config.validator.load_opt_data')
@@ -107,7 +102,7 @@ class TestValidator(base.BaseTestCase):
                                  input_file='mocked.conf',
                                  exclude_group=['oo'])
         m = mock.mock_open(read_data=MISSING_GROUP_CONF)
-        with mock.patch(self.open_name, m):
+        with mock.patch('builtins.open', m):
             self.assertEqual(0, validator._validate(self.conf))
 
     def test_invalid_options(self):
diff --git a/oslo_config/types.py b/oslo_config/types.py
index 223fffb..dfd89bc 100644
--- a/oslo_config/types.py
+++ b/oslo_config/types.py
@@ -28,12 +28,10 @@ import abc
 from debtcollector import removals
 import netaddr
 import rfc3986
-import six
-from six.moves import range as compat_range
 
 
-@six.add_metaclass(abc.ABCMeta)
-class ConfigType(object):
+class ConfigType(object, metaclass=abc.ABCMeta):
+
     def __init__(self, type_name='unknown type'):
         self.type_name = type_name
 
@@ -44,7 +42,7 @@ class ConfigType(object):
 
         """
         if sample_default is not None:
-            if isinstance(sample_default, six.string_types):
+            if isinstance(sample_default, str):
                 default_str = sample_default
             else:
                 default_str = self._formatter(sample_default)
@@ -55,9 +53,9 @@ class ConfigType(object):
         return [default_str]
 
     def quote_trailing_and_leading_space(self, str_val):
-        if not isinstance(str_val, six.string_types):
+        if not isinstance(str_val, str):
             warnings.warn('converting \'%s\' to a string' % str_val)
-            str_val = six.text_type(str_val)
+            str_val = str(str_val)
         if str_val.strip() != str_val:
             return '"%s"' % str_val
         return str_val
@@ -135,7 +133,7 @@ class String(ConfigType):
             re_flags = re.IGNORECASE if self.ignore_case else 0
 
             # Check if regex is a string or an already compiled regex
-            if isinstance(regex, six.string_types):
+            if isinstance(regex, str):
                 self.regex = re.compile(regex, re_flags)
             else:
                 self.regex = re.compile(regex.pattern, re_flags | regex.flags)
@@ -351,7 +349,7 @@ class Number(ConfigType):
         )
 
     def _formatter(self, value):
-        return six.text_type(value)
+        return str(value)
 
 
 class Integer(Number):
@@ -484,7 +482,7 @@ class List(ConfigType):
 
     def __call__(self, value):
         if isinstance(value, (list, tuple)):
-            return list(six.moves.map(self.item_type, value))
+            return list(map(self.item_type, value))
 
         s = value.strip().rstrip(',')
         if self.bounds:
@@ -531,7 +529,7 @@ class List(ConfigType):
 
     def _formatter(self, value):
         fmtstr = '[{}]' if self.bounds else '{}'
-        if isinstance(value, six.string_types):
+        if isinstance(value, str):
             return fmtstr.format(value)
         if isinstance(value, list):
             value = [
@@ -585,7 +583,7 @@ class Range(ConfigType):
             step = -1
         if self.inclusive:
             right += step
-        return compat_range(left, right, step)
+        return range(left, right, step)
 
     def __eq__(self, other):
         return (
diff --git a/requirements.txt b/requirements.txt
index 5a20c04..70a27d7 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,7 +4,6 @@
 
 debtcollector>=1.2.0 # Apache-2.0
 netaddr>=0.7.18 # BSD
-six>=1.10.0 # MIT
 stevedore>=1.20.0 # Apache-2.0
 oslo.i18n>=3.15.3 # Apache-2.0
 rfc3986>=1.2.0 # Apache-2.0
diff --git a/test-requirements.txt b/test-requirements.txt
index b6e4dda..0d3ddef 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -20,7 +20,8 @@ oslo.log>=3.36.0  # Apache-2.0
 #  deps = {[testenv]deps} coverage
 coverage!=4.4,>=4.0 # Apache-2.0
 
-# mocking framework
+# we can switch to unittest.mock once we drop support for Python 3.6 as that
+# includes https://bugs.python.org/issue32933
 mock>=3.0.0 # BSD
 requests_mock>=1.5.0 # Apache-2.0