Add Python 3 support

These are the final changes needed to have the full py33 tox environment
running and passing all tests.

Change-Id: I3ac149345561a5bb99e017022ba2e2be10154584

oslo/config/cfg.py

@@ -370,7 +370,7 @@ class ConfigFilesNotFoundError(Error):
 
     def __str__(self):
         return ('Failed to read some config files: %s' %
-                string.join(self.config_files, ','))
+                ",".join(self.config_files))
 
 
 class ConfigFileParseError(Error):
@@ -715,6 +715,13 @@ class Opt(object):
 
         return self._get_argparse_prefix(prefix, dgroup) + dname
 
+    def __lt__(self, another):
+        return hash(self) < hash(another)
+
+# NOTE(jd) Not available for py2.6
+if six.PY3:
+    Opt = functools.total_ordering(Opt)
+
 
 class DeprecatedOpt(object):
 
@@ -988,6 +995,9 @@ class SubCommandOpt(Opt):
                                            title=self.title,
                                            description=self.description,
                                            help=self.help)
+        # NOTE(jd) Set explicitely to True for Python 3
+        # See http://bugs.python.org/issue9253 for context
+        subparsers.required = True
 
         if self.handler is not None:
             self.handler(subparsers)
@@ -1610,7 +1620,10 @@ class ConfigOpts(collections.Mapping):
         :returns: the option value (after string subsititution) or a GroupAttr
         :raises: NoSuchOptError,ConfigFileValueError,TemplateSubstitutionError
         """
+        try:
             return self._get(name)
+        except Exception:
+            raise AttributeError
 
     def __getitem__(self, key):
         """Look up an option value and perform string substitution."""

test-requirements-py3.txt

@@ -0,0 +1,21 @@
+# Install bounded pep8/pyflakes first, then let flake8 install
+pep8==1.4.5
+pyflakes==0.7.2
+flake8==2.0
+hacking>=0.5.3,<0.6
+
+discover
+fixtures>=0.3.12
+python-subunit
+-e bzr+lp:testrepository#egg=testrepository
+testscenarios<0.5
+testtools>=0.9.29
+
+# when we can require tox>= 1.4, this can go into tox.ini:
+#  [testenv:cover]
+#  deps = {[testenv]deps} coverage
+coverage
+
+# this is required for the docs build jobs
+sphinx
+oslo.sphinx

tests/test_cfg.py

@@ -23,6 +23,7 @@ import fixtures
 import testscenarios
 
 from oslo.config import cfg
+import six
 from six import moves
 from tests import utils
 
@@ -2155,7 +2156,8 @@ class SadPathTestCase(BaseTestCase):
     def test_unknown_attr(self):
         self.conf([])
         self.assertFalse(hasattr(self.conf, 'foo'))
-        self.assertRaises(cfg.NoSuchOptError, getattr, self.conf, 'foo')
+        self.assertRaises(AttributeError, getattr, self.conf, 'foo')
+        self.assertRaises(cfg.NoSuchOptError, self.conf._get, 'foo')
 
     def test_unknown_attr_is_attr_error(self):
         self.conf([])
@@ -2257,7 +2259,8 @@ class SadPathTestCase(BaseTestCase):
 
         self.conf(['--config-file', paths[0]])
 
-        self.assertRaises(cfg.ConfigFileValueError, getattr, self.conf, 'foo')
+        self.assertRaises(AttributeError, getattr, self.conf, 'foo')
+        self.assertRaises(cfg.ConfigFileValueError, self.conf._get, 'foo')
 
     def test_conf_file_bad_bool(self):
         self._do_test_conf_file_bad_value(cfg.BoolOpt)
@@ -2277,7 +2280,9 @@ class SadPathTestCase(BaseTestCase):
 
         self.assertFalse(hasattr(self.conf, 'bar'))
         self.assertRaises(
-            cfg.TemplateSubstitutionError, getattr, self.conf, 'bar')
+            AttributeError, getattr, self.conf, 'bar')
+        self.assertRaises(
+            cfg.TemplateSubstitutionError, self.conf._get, 'bar')
 
     def test_set_default_unknown_attr(self):
         self.conf([])
@@ -2438,7 +2443,7 @@ class ConfigParserTestCase(BaseTestCase):
 
     def test_no_section(self):
         with tempfile.NamedTemporaryFile() as tmpfile:
-            tmpfile.write('foo = bar')
+            tmpfile.write(six.b('foo = bar'))
             tmpfile.flush()
 
             parser = cfg.ConfigParser(tmpfile.name, {})
@@ -2812,7 +2817,8 @@ class ChoicesTestCase(BaseTestCase):
 
         self.conf(['--config-file', paths[0]])
 
-        self.assertRaises(cfg.ConfigFileValueError, getattr, self.conf, 'foo')
+        self.assertRaises(cfg.ConfigFileValueError, self.conf._get, 'foo')
+        self.assertRaises(AttributeError, getattr, self.conf, 'foo')
 
     def test_conf_file_choice_value_override(self):
         self.conf.register_cli_opt(cfg.StrOpt('foo',

tox.ini

@@ -7,6 +7,9 @@ deps = -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
 commands = python setup.py testr --slowest --testr-args='{posargs}'
 
+[testenv:py33]
+deps = -r{toxinidir}/test-requirements-py3.txt
+
 [testenv:pep8]
 commands = flake8