Shouldn't use unicode() when exception used in msgs

[James Carey]

There are cases (identified by mriedem) where an exception is used as replacement text and is coerced using unicode():

http://git.openstack.org/cgit/openstack/nova/tree/nova/compute/manager.py?id=2014.2.rc2#n3264

   reason=_("Driver Error: %s") % unicode(e))

http://git.openstack.org/cgit/openstack/nova/tree/nova/api/ec2/__init__.py?id=2014.2.rc2#n89

   LOG.exception(_("FaultWrapper: %s"), unicode(ex))

doing this can interfere with translation by causing things to be prematurely translated.

Need to scan for and correct any occurrences. Also need to look at adding/updating a hacking check.

[Matt Riedemann (mriedem)]

Is there a way to have a hacking check for this?

[Matt Riedemann (mriedem)]

For example, could we find out we're in an except block and handling an exception somehow, and that unicode() is being used? Then figure out it's the thing we're trying to avoid.

[James Carey (jecarey)]

I'm in the process of extending N325 to include this so it would go from:

      N325 str() cannot be used on an exception. Remove or use six.text_type()

to:

      N325 str() and unicode() cannot be used on an exception. Remove or use six.text_type()

I'm working through the things this flags now and will push up a patch.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/129473

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/129473
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=6683905b532b6030989064636aa5506d4cbe5b22
Submitter: Jenkins
Branch: master

commit 6683905b532b6030989064636aa5506d4cbe5b22
Author: James Carey <email address hidden>
Date: Fri Oct 17 13:14:26 2014 -0700

    Remove use of unicode on exceptions

    Casting exceptions to unicode using unicode() can interfere
    with the proper translation of the exception message. This
    is especially true when lazy translation is enabled, since it
    causes the exception message to be translated immediately using
    the default locale.

    This is the same problem caused by using str on exceptions,
    which was fixed by https://review.openstack.org/#/c/116054/

    In addition to fixing these cases, this patch updates
    hacking check N325, which checks for the use of str() on
    exceptions, to also check for the use of unicode().

    In order to make it clear which cases that cannot be caught
    by the hacking check have been inspected, they have been
    converted to using six.text_type() instead of unicode().

    Closes-bug: #1380806
    Change-Id: I87bb94fa76458e028beba28d092320057b53f70a

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/170156

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/170156
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=319bddcc03fd28a709de08f52ebe4f8ae20a6061
Submitter: Jenkins
Branch: master

commit 319bddcc03fd28a709de08f52ebe4f8ae20a6061
Author: Ivan Kolodyazhny <email address hidden>
Date: Thu Apr 2 17:55:48 2015 +0300

    Use six.text_type instead of unicode

    Add hacking checks for unicode() calls

    Change-Id: I27062986e69a90e3f4fc26a76080b146e825149b
    Closes-Bug: #1380806