Decode argv to Unicode on py2

Decode default argv into Unicode on Python 2 (Python 3 does this
under the covers).

Backport of OSC change https://review.openstack.org/#/c/343035/

Co-Authored-By: John Dennis <jdennis@redhat.com>
Related-Bug: 1603494
Change-Id: I192f17962bb5e21c20c3743b8f3e88c2450432c7

osc_lib/shell.py

@@ -18,6 +18,7 @@
 
 import argparse
 import getpass
+import locale
 import logging
 import sys
 import traceback
@@ -28,6 +29,7 @@ from cliff import complete
 from cliff import help
 from oslo_utils import importutils
 from oslo_utils import strutils
+import six
 
 from osc_lib.cli import client_config as cloud_config
 from osc_lib import clientmanager
@@ -458,8 +460,17 @@ class OpenStackShell(app.App):
             tcmd.run(targs)
 
 
-def main(argv=sys.argv[1:]):
+def main(argv=None):
+    if argv is None:
+        argv = sys.argv[1:]
+        if six.PY2:
+            # Emulate Py3, decode argv into Unicode based on locale so that
+            # commands always see arguments as text instead of binary data
+            encoding = locale.getpreferredencoding()
+            if encoding:
+                argv = map(lambda arg: arg.decode(encoding), argv)
     return OpenStackShell().run(argv)
 
+
 if __name__ == "__main__":
     sys.exit(main(sys.argv[1:]))

osc_lib/tests/test_shell.py

@@ -16,8 +16,10 @@
 import copy
 import mock
 import os
+import sys
 import testtools
 
+from osc_lib import shell
 from osc_lib.tests import utils
 
 
@@ -115,6 +117,38 @@ global_options = {
 }
 
 
+class TestShellArgV(utils.TestShell):
+    """Test the deferred help flag"""
+
+    def setUp(self):
+        super(TestShellArgV, self).setUp()
+
+    def test_shell_argv(self):
+        """Test argv decoding
+
+        Python 2 does nothing with argv while Python 3 decodes it into
+        Unicode before we ever see it.  We manually decode when running
+        under Python 2 so verify that we get the right argv types.
+
+        Use the argv supplied by the test runner so we get actual Python
+        runtime behaviour; we only need to check the type of argv[0]
+        which will alwyas be present.
+        """
+
+        with mock.patch(
+                "osc_lib.shell.OpenStackShell.run",
+                self.app,
+        ):
+            # Ensure type gets through unmolested through shell.main()
+            argv = sys.argv
+            shell.main(sys.argv)
+            self.assertEqual(type(argv[0]), type(self.app.call_args[0][0][0]))
+
+            # When shell.main() gets sys.argv itself it should be decoded
+            shell.main()
+            self.assertEqual(type(u'x'), type(self.app.call_args[0][0][0]))
+
+
 class TestShellHelp(utils.TestShell):
     """Test the deferred help flag"""
 

releasenotes/notes/shell-argv-decode-cdc13dc0c4ec07af.yaml

@@ -0,0 +1,5 @@
+---
+fixes:
+  - |
+    Decode argv into Unicode on Python 2 in ``OpenStackShell.main()``
+    [OSC Bug `1603494 <https://bugs.launchpad.net/bugs/1603494>`_]