msg argument to assert* method is concatenated before calling repr, unicode or str.

What steps will reproduce the problem?
1. Call a failing assert* method
2. Pass as msg some value that is not concatenable with basestring

What is the expected output? What do you see instead?

I expect to see the standard message with my message inserted (through 
string interpolation for example.

I see
<pre>
ERROR: The view should set the appropriate context variables.
---------------------------------------------------------
-------------
Traceback (most recent call last):
  File "/Users/ryszard/SetJam/setjam/site-python/unittest2/case.py", line 
324, in run
    testMethod()
  File 
"/Users/ryszard/SetJam/setjam/setjam/subscriptions/tests/test_views.py", 
line 217, in test_context
    self.assertSameElements(r.context['seasons'], [1, 2], r.context['seasons'])
  File "/Users/ryszard/SetJam/setjam/site-python/unittest2/case.py", line 
848, in assertSameElements
    self.fail(self._formatMessage(msg, standardMsg))
  File "/Users/ryszard/SetJam/setjam/site-python/unittest2/case.py", line 
424, in _formatMessage
    return standardMsg + ' : ' + msg
TypeError: cannot concatenate 'str' and 'ValuesListQuerySet' objects
</pre>

Original issue reported on code.google.com by ryszard....@gmail.com on 6 Mar 2010 at 3:23

testing-cabal / unittest-ext

msg argument to assert* method is concatenated before calling repr, unicode or str. #7