Config generator fails with lazy messages

Entry points from modules loaded from projects may have help text
that is i18n lazy enabled, which causes a failure because
gettextutils.Message (a subclass of six.text_type) explicitly
does not support concatenation.  Change from using concatenation
to using format (%) to allow six.text_type to do the right thing.

Change-Id: Ie60c569ae6fe227e16eef4a3281cf042732addc3
Closes-Bug: #1280826

openstack/common/config/generator.py

@@ -247,7 +247,8 @@ def _print_opt(opt):
     except (ValueError, AttributeError) as err:
         sys.stderr.write("%s\n" % str(err))
         sys.exit(1)
-    opt_help += ' (' + OPT_TYPES[opt_type] + ')'
+    opt_help = u'%s (%s)' % (opt_help,
+                             OPT_TYPES[opt_type])
     print('#', "\n# ".join(textwrap.wrap(opt_help, WORDWRAP_WIDTH)))
     if opt.deprecated_opts:
         for deprecated_opt in opt.deprecated_opts:

tests/testmods/i18n_opt.py

@@ -0,0 +1,27 @@
+# Copyright 2014 IBM Corp.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from openstack.common import gettextutils
+from oslo.config import cfg
+
+CONF = cfg.CONF
+
+# Note that this is using the Message class directly instead of using
+# gettextutils.enable_lazy() because this isolates the use of
+# the Message class to this one instance instead of turning it on
+# for all subsequent tests
+opt = cfg.StrOpt('i18n', default="i18n",
+                 help=gettextutils.Message('helpful message'))
+
+CONF.register_opt(opt, group='i18n')

tests/testmods/unicode_opt.py

@@ -0,0 +1,23 @@
+# Copyright 2014 IBM Corp.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from oslo.config import cfg
+
+CONF = cfg.CONF
+
+# Use a unicode value that causes an exception if str() is used
+opt = cfg.StrOpt('unicode_opt', default="unicode_default",
+                 help=u'helpful message with unicode char: \xE7\x94\xB5')
+
+CONF.register_opt(opt, group='unicode_group')

tests/unit/config/test_generator.py

@@ -30,6 +30,10 @@ class GeneratorTestcase(test.BaseTestCase):
                  "tests/testmods/bar_foo_opt.py",
                  "tests/testmods/fblaa_opt"]
 
+    conffiles_i18n = ["tests/testmods/i18n_opt"]
+
+    conffiles_unicode = ["tests/testmods/unicode_opt"]
+
     def setUp(self):
         super(GeneratorTestcase, self).setUp()
         self.groups = []
@@ -63,3 +67,32 @@ class GeneratorTestcase(test.BaseTestCase):
         self.assertIn('#baa=<None>\n', lines)
         self.assertIn('#foo=<None>\n', lines)
         self.assertIn('#fblaa=fblaa\n', lines)
+
+    def test_i18n(self):
+        stdout = self.useFixture(fixtures.StringStream('confstdout')).stream
+        self.useFixture(mockpatch.Patch('sys.stdout', new=stdout))
+        generator.generate(self.conffiles_i18n)
+        stdout.flush()
+        stdout.seek(0)
+        lines = stdout.readlines()
+        # Test we have group in the output
+        self.assertIn('[i18n]\n', lines)
+        # Test we have opt in the output
+        self.assertIn('#i18n=i18n\n', lines)
+        # Test we have help in the output
+        self.assertIn('# helpful message (string value)\n', lines)
+
+    def test_unicode(self):
+        stdout = self.useFixture(fixtures.StringStream('confstdout')).stream
+        self.useFixture(mockpatch.Patch('sys.stdout', new=stdout))
+        generator.generate(self.conffiles_unicode)
+        stdout.flush()
+        stdout.seek(0)
+        lines = stdout.readlines()
+        # Test we have group in the output
+        self.assertIn('[unicode_group]\n', lines)
+        # Test we have opt in the output
+        self.assertIn('#unicode_opt=unicode_default\n', lines)
+        # Test we have help in the output
+        self.assertIn(u'# helpful message with unicode char:'
+                      u' \xE7\x94\xB5 (string value)\n', lines)